"uuid","repository link","title","author","contributor","publication year","abstract","subject topic","language","publication type","publisher","isbn","issn","patent","patent status","bibliographic note","access restriction","embargo date","faculty","department","research group","programme","project","coordinates" "uuid:2f0f4ac3-66de-45cb-83c0-2a258fdd634a","http://resolver.tudelft.nl/uuid:2f0f4ac3-66de-45cb-83c0-2a258fdd634a","Assessment criteria for inter-organizational collaboration in interconnected infrastructure projects","Rikhtegarnezami, M. (TU Delft Integral Design & Management); de Bruijne, M.L.C. (TU Delft Organisation & Governance); Hertogh, M.J.C.M. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2024","Purpose: Societies depend on interconnected infrastructures that are becoming more complex over the years. Multi-disciplinary knowledge and skills are essential to develop modern infrastructures, requiring close collaboration of various infrastructure owners. To effectively manage and improve inter-organizational collaboration (IOC) in infrastructure construction projects, collaboration status should be assessed continually. This study identifies the assessment criteria, forming the foundation of a tool for assessing the status of IOC in interconnected infrastructure projects.
Design/methodology/approach: A systematic literature study and in-depth semi-structured interviews with practitioners in interconnected infrastructure construction projects in the Netherlands are performed to identify the criteria for assessing the status of IOC in infrastructure construction projects, based on which an assessment tool is developed.
Findings: The identified assessment criteria through the literature and the practitioner’s perspectives results in the designing and development of a collaboration assessment tool. The assessment tool consists of 12 criteria and 36 sub-criteria from three different categories of collaborative capacity: individual, relational, and organizational.
Originality/value: The assessment tool enables practitioners to monitor the status of IOC between infrastructure owners and assists them in making informed decisions to enhance collaboration. The assessment tool provides the opportunity to assess and analyze the status of collaboration based on three categories (i.e., individual, relational, and organizational).","Assessment tool; Construction industry; Horizontal collaboration; Inter-organizational collaboration; Interconnected infrastructure","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:ae6347bb-86e3-4b0a-ab89-ecf6b8a71e30","http://resolver.tudelft.nl/uuid:ae6347bb-86e3-4b0a-ab89-ecf6b8a71e30","Towards Circular ICUs: Circular Intubations as a Catalyser for Systemic Change","Ville, Alicia (Student TU Delft); Hunfeld, Nicole (Erasmus MC); Bakker, C.A. (TU Delft Circular Product Design); Sené, Baptiste (Van Berlo); Diehl, J.C. (TU Delft Design for Sustainability)","Melles, M. (editor); Goossens, R.H. (editor)","2024","This project aims to reduce the environmental impact of the Intensive Care Unit (ICU) of the Erasmus Medical Center (EMC). Systemic design research was executed to map the current waste flow created by the ICU. Literature review, interviews and observations were performed to gather information about the healthcare protocols, hospital procurement process, intubation practices and used devices and consumables. This resulted in a set of challenges which were used to ideate from different perspectives to improve the sustainability of the ICU. A set of opportunities to introduce circularity within the ICU were defined. These opportunities ranged from waste separation to the reduction of the disposal of unused products. The selected circular opportunity was intubation, needed when patients cannot breathe by themselves. For this, a video laryngoscope, which is composed of various plastics, a video camera, and a led light, is used for only a few minutes and disposed of (and incinerated) directly afterwards. The aim of the second part of this research project was: Can we design a circular intubation procedure as a catalyzer for systemic change towards circular ICUs? One of the proposed circular strategies for the video laryngoscope is the reprocessing of intubation devices used at the ICU itself. A transition model toward reprocessing using UV-C radiation technique was further developed. Compared to current reprocessing procedures, UV-C disinfection consumes no water and less electricity and offers the possibility of decentralized reprocessing within the ICU department itself. This project aims to provoke conversations between the hospital, manufacturers and other stakeholders about how the healthcare sector could start reprocessing valuable medical devices towards a circular ICU.","Circular healthcare; Systemic design; Intensive Care Unit; Intubation","en","conference paper","Springer","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2024-05-05","","","Circular Product Design","","",""
"uuid:52cd2325-280b-4c22-9398-24588bccbbb3","http://resolver.tudelft.nl/uuid:52cd2325-280b-4c22-9398-24588bccbbb3","Employee Perspectives on Risk Management in a Construction Company","Ökmen, Ö. (TU Delft Integral Design & Management); Leijten, M. (TU Delft Organisation & Governance); Strattona, Theodora (Student TU Delft); Bosch-Rekveldt, M.G.C. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2024","In addition to the tools and techniques available, project risk management also depends on the attitudes of people in an organisation, how the available tools are used, and how the procedures are followed. Therefore, efforts to improve the project risk management capacity of organisations may fail if the diversity of people (characters, traits etc.) involved is neglected. Based on this argument, the aim of this study is to demonstrate that companies can improve project risk management using the perspectives of their key experts. In this context, an approach was proposed based on Q-Methodology and a case study has been conducted in a construction company in the Netherlands. The quantitative output obtained through Q-Methodology application was evaluated in conjunction with the qualitative data gathered from interviews conducted with the managers of different units within the company. As a result of this evaluation, three common perspectives were identified among the respondents under the names of ‘Experience and Belief’, ‘Procedures and Management’ and ‘Culture and Communication’, respectively. Then, a number of recommendations were made to the company. First, customized management approaches that integrate and balance the identified perspectives should be adopted. Second, a mature organisational risk management culture should be promoted. Project charters that specifically target risk management culture in projects can be used for this purpose. Third, risk management should be integrated into other activities, making it a normal part of employees’ daily work. Finally, but not exclusively, the employees should be instructed on the use of risk registers and guidance should be put in place on how often they are expected to update the risk registers. This study demonstrates the benefit of considering employee diversity and leveraging perspectives in unlocking the potential of construction companies in terms of project risk management.","construction companies; critical success factors; Netherlands; Project risk management; Q-Methodology","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:f9966be1-6a47-48e5-9f4e-14f3160496a0","http://resolver.tudelft.nl/uuid:f9966be1-6a47-48e5-9f4e-14f3160496a0","Multi-Robot Local Motion Planning Using Dynamic Optimization Fabrics","Bakker, S. (TU Delft Learning & Autonomous Control); Knödler, L. (TU Delft Learning & Autonomous Control); Spahn, M. (TU Delft Learning & Autonomous Control); Böhmer, J.W. (TU Delft Algorithmics); Alonso-Mora, J. (TU Delft Learning & Autonomous Control)","","2024","In this paper, we address the problem of real-time motion planning for multiple robotic manipulators that operate in close proximity. We build upon the concept of dynamic fabrics and extend them to multi-robot systems, referred to as Multi-Robot Dynamic Fabrics (MRDF). This geometric method enables a very high planning frequency for high-dimensional systems at the expense of being reactive and prone to deadlocks. To detect and resolve deadlocks, we propose Rollout Fabrics where MRDF are forward simulated in a decentralized manner. We validate the methods in simulated close-proximity pick-and-place scenarios with multiple manipulators, showing high-success rates and real-time performance. Code, video: https://github.com/tud-amr/multi-robot-fabrics","","en","conference paper","IEEE","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2024-08-05","","","Learning & Autonomous Control","","",""
"uuid:d2d035ff-40ff-4867-9f4a-3d11fe9c8c62","http://resolver.tudelft.nl/uuid:d2d035ff-40ff-4867-9f4a-3d11fe9c8c62","Reverse bias degradation of CIGS solar cells","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices)","Weeber, A.W. (promotor); Zeman, M. (promotor); Theelen, M.J. (copromotor); Delft University of Technology (degree granting institution)","2023","","","en","doctoral thesis","","978-94-6483-307-2","","","","","","","","","Photovoltaic Materials and Devices","","",""
"uuid:d8bb9275-6f3f-400c-a4e2-52f4bfce74f6","http://resolver.tudelft.nl/uuid:d8bb9275-6f3f-400c-a4e2-52f4bfce74f6","A framework for assessing the remaining life of storm surge barriers","Vader, Hidde (Deltares; Royal HaskoningDHV; Student TU Delft); Bakker, A.M.R. (TU Delft Hydraulic Structures and Flood Risk; Rijkswaterstaat); Jonkman, Sebastiaan N. (TU Delft Hydraulic Structures and Flood Risk); van den Boomen, M. (TU Delft Integral Design & Management); van Baaren, Esther (Deltares); Diermanse, Ferdinand L.M. (Deltares)","","2023","Over the course of the last century, storm surge barriers have been built in several countries and proven to be successful in preventing flooding. However, the operation, reliability, and remaining life of these structures have come under increased pressure due to changing demands, intensified utilisation, and climate change. Yet, there is relatively little known about how these factors affect the remaining life of storm surge barriers. To address this issue, a framework is presented to assess the impacts of external drivers on the remaining life in a systematic manner. The framework considers both the technical state and functional performance and uses scenarios to evaluate the impact of external drivers. The application of the framework is demonstrated for the Hollandsche IJssel barrier (the Netherlands). The results indicate that sea level rise (SLR) is the dominant physical driver. Even in moderate SLR scenarios, the lifespan of the barrier may end in the 2040s if the functional performance with respect to flood protection and navigation cannot be improved. Ultimately, the study demonstrates how the remaining life of storm surge barriers could be assessed systematically and the impact of external drivers on the remaining life could be evaluated.","Flood defences; functional life; hydraulic structures; lifespan; remaining life; sea level rise; storm surge barriers","en","journal article","","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:88317cb3-aa42-4bce-9bd3-c9e1b3d3f8d7","http://resolver.tudelft.nl/uuid:88317cb3-aa42-4bce-9bd3-c9e1b3d3f8d7","Embedded rocking measurement of single layer armour units: Development and first results","Houtzager, Daan (Student TU Delft; Reefy); Hofland, Bas (TU Delft Hydraulic Structures and Flood Risk; Deltares); Caldera, Ganga (Student TU Delft; Delta Marine Consultants); van der Lem, Cock (Royal HaskoningDHV); van Gent, M.R.A. (TU Delft Coastal Engineering; Deltares); Bakker, Pieter (Delta Marine Consultants); Antonini, A. (TU Delft Coastal Engineering)","","2023","Randomly placed breakwater armour units under wave loading can sometimes start rocking, which can lead to breakage of armour units. This failure mechanism can especially become important for single layer randomly placed armour units for which full displacement of units will only happen at higher stability numbers compared to older types of units, and where unit breakage can more easily lead to progressive damage to the armour layer. However, unlike older types of units, hardly any quantitative information is available on the impact velocities, and the number of impacts is mostly assessed using somewhat subjective visual observations. In design the observed number of rocking units is limited to the amount of visually observed rocking units. Hence a good quantification of impact velocities could lead to a more optimal design. This paper describes the further development of embedded rocking sensors to measure the motions of individual smart armour units. Multiple smart rocking sensors have been applied in a physical model of a breakwater and measurements were collected to determine the number of impacts and impact velocity of the armour units. The results have been compared to visual observations and the first results will be presented. It is concluded that the new technique can be used to obtain much more information on rocking, including impact velocities, and that more rocking occurs than is observed visually.","","en","conference paper","Institution of Civil Engineers","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-10-27","","","Hydraulic Structures and Flood Risk","","",""
"uuid:7159328e-f115-4497-b7db-a3d4058ec37f","http://resolver.tudelft.nl/uuid:7159328e-f115-4497-b7db-a3d4058ec37f","The extent to which circular economy principles have been applied in the design of medical devices for low-resource settings in Sub-Saharan Africa.: A systematic review","Samenjo, K.T. (TU Delft Design for Sustainability); Oosting, R.M. (TU Delft Medical Instruments & Bio-Inspired Technology); Bakker, C.A. (TU Delft Circular Product Design); Diehl, J.C. (TU Delft Design for Sustainability)","","2023","Healthcare facilities in low-resource settings in Sub-Saharan Africa are plagued
with issues of non-functional and obsolete medical devices, which ultimately
end up prematurely disposed of as waste. With increasing healthcare demands,
stopping medical device disposal is imperative. One way to achieve this is
to leverage circular economy principles in designing medical devices. Circular
economy principles aim to retain products and their constituent materials to
be reused over time in the economic system. However, to what extent this has
been applied in designing medical devices specifically for low-resource settings
in Sub-Saharan Africa is missing in literature. Based on a systematic review of
29 out of 1,799 screened scientific papers, we identified the use of circular
economy principles of durability, maintenance, repair, and upgrade in designing
medical devices for this setting. Whether these principles were intentionally
applied from a circular economy approach could not be inferred in this study.
The motivational basis for using these principles was to ensure medical device
longevity to providing healthcare. No attention was given to the circular economy
principles of refurbishment, remanufacturing, and recycling, ensuring that device
components and constituent materials are recovered. These study findings serve
as a launchpad for exploring how circular principles can be used to support
the design of medical devices for low-resource settings in Sub-Saharan Africa.
Academicians and designers of medical devices can leverage this research to
contribute towards developing medical devices that support access to healthcare
for people in low-resource settings and preserve earth’s finite resources","circular economy principles; medical device design; low-resource settings; Sub-Saharan Africa; product design","en","journal article","","","","","","","","","","","Design for Sustainability","","",""
"uuid:adddd872-0e0c-41a0-9981-70d07ee35f27","http://resolver.tudelft.nl/uuid:adddd872-0e0c-41a0-9981-70d07ee35f27","Applying vertical greening systems to reduce traffic noise in outdoor environments: Overview of key design parameters and research methods","Bakker, J.J. (TU Delft Building Physics); Lugten, M.C. (TU Delft Environmental & Climate Design); Tenpierik, M.J. (TU Delft Environmental & Climate Design)","","2023","Vertical greening can be used to absorb and scatter sound, which may reduce noise levels in street canyons. In this paper, a literature review is presented, which combines results and methods from over 40 individual studies. The article describes the guiding principles behind the acoustic effects of vertical greening and provides an overview of the prevalent research methods. The article shows that vertical greenery is effective for the reduction of mid and high frequency noise, unless air cavities or resonators are introduced inside, or behind, the systems. The review also reflects on studies with an emphasis on the application of vertical greenery in streets and urban blocks. The aim of the article is to set out the key design parameters for noise reduction that can be achieved by vertical greening, focusing on designers and engineers.","literature review; sound absorption; Vertical greening","en","review","","","","","","","","","","","Building Physics","","",""
"uuid:4986cb3a-6962-4256-9ced-a89359563026","http://resolver.tudelft.nl/uuid:4986cb3a-6962-4256-9ced-a89359563026","Rapareren als aandrijver van de circulaire economie","Bakker, C.A. (TU Delft Design for Sustainability)","Balkenende, Ruud (editor); Bakker, Conny (editor); Blondel, Elise (editor); Henneberry, Yumiko (editor)","2023","","product repair; Product Design; Circular economy; business model; European Legislation","nl","book chapter","Het Leiden-Delft-Erasmus Centre for Sustainability","","","","","","","","","","Design for Sustainability","","",""
"uuid:0f696bce-7542-47e5-ad81-394ec84e3638","http://resolver.tudelft.nl/uuid:0f696bce-7542-47e5-ad81-394ec84e3638","A model predictive control approach towards the energy efficiency of submerged dredging","Bakker, Mathijs (C-Job Naval Architects); Coraddu, A. (TU Delft Ship Design, Production and Operations); Hijdra, Rolph (C-Job Naval Architects)","","2023","Autonomous submerged dredging offers numerous benefits, such as reduced ship resistance and lower vacuum requirements for the dredge pumps. However, this method also presents new challenges, such as stability and buoyancy control, which must be addressed to minimize the energy requirements and ensure cost-effectiveness and sustainability. To achieve these goals, this paper proposes a Model Predictive Control (MPC) strategy to minimize control effort and energy requirements. Compared to traditional motion control methods such as proportional–integral–derivative (PID) control, MPC shows great promise in terms of energy efficiency and trajectory-tracking. The Autonomous Low Energy Replenishment Dredger (ALERD) is used as a case study to showcase the potential of the proposed control strategy. A time-domain simulation model is developed, and the ALERD is modeled as an underwater vehicle using a state-space representation. The classic PID control and the proposed MPC framework are compared in terms of trajectory-tracking, energy requirements, and robustness to modeling uncertainties, using sensitivity analysis. The results show that the proposed MPC control framework outperforms PID control in all aspects considered. Furthermore, a comparison between the energy requirements of the ALERD and a conventional dredger, for the same operational profile and hopper volume, indicates that autonomous submerged dredging can potentially decrease total energy requirements by 66%.","Autonomous shipping; Dredging; Model predictive control; Monte Carlo simulation; Underwater vehicles","en","journal article","","","","","","","","","","","Ship Design, Production and Operations","","",""
"uuid:d6af4260-5ebf-4c29-95c4-3f0256b31aac","http://resolver.tudelft.nl/uuid:d6af4260-5ebf-4c29-95c4-3f0256b31aac","The potential of the empathic ability for the performance of civil engineering projects","Keusters, A.C.A.M. (TU Delft Integral Design & Management); Batelaan, F.G.M. (TU Delft Integral Design & Management); Sleeswijk Visser, F. (TU Delft Design Conceptualization and Communication); Houwing, E.J. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2023","Purpose:
The increasing complexity of civil engineering projects necessitates focusing on new competencies of project participants. Based on the research on team performance and design processes that are more closely linked to the relevance of the project context, it is hypothesised that empathic abilities could play an important role in the performance of civil engineering projects. Therefore, this study aims to investigate whether performance can be improved by focusing on empathic abilities during the integrated design phase.
Design/methodology/approach:
Semi-structured in-depth interviews with experts were conducted to explore the relevance of empathic abilities and their interaction with performance in a real-life infrastructure project. The project team’s empathy level was measured by means of a survey using Davis’ Interpersonal Reactivity Index method. Finally, differences between expected and measured levels of empathy were analysed.
Findings:
The results provide insights into how empathic abilities interact with performance. The measurement indicates that, on average, professionals in the civil engineering industry score relatively low on empathy. In addition, differences were identified between the expected distribution and the measured empathy levels of the team, implying a potential for improvement, in particular by increasing the empathic abilities of the project management and increasing gender diversity.
Originality/value:
To the best of the authors’ knowledge, this study is the first to investigate a relationship between empathy and the performance of civil engineering projects. The results provide initial insights into the empathic ability of civil engineering project teams and the potential of empathy to improve performance. Furthermore, from an empathy perspective, this study advocates increasing the gender diversity of project teams to improve performance.","Design; Diversity; Empathy; Project management; Project performance","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:5e7e05e7-1c58-4308-9c06-a7a25fe11e90","http://resolver.tudelft.nl/uuid:5e7e05e7-1c58-4308-9c06-a7a25fe11e90","Circular design in practice: Eight levers for change","Hanes-Gadd, Merryn (University of Exeter); Bakker, C.A. (TU Delft Circular Product Design); Charnley, Fiona (University of Exeter)","","2023","Circular Design, as a practice and approach, has grown in popularity in the last decade, with academics and industry alike proposing many strategies and methods that facilitate this in products. Yet, very few day-to-day products are actually circular. Therefore, in this chapter, we sought to analyse and reflect upon what progress Circular Design has made within industry, uncovering the key barriers and opportunities for how it is implemented. Through interviews with industry experts applying Circular Design in practice, this chapter identified the 'classic drivers and barriers' influencing the sustainability of products but also identified several new insights or 'levers for change' that are impacting the advancement as well. It is proposed that if these levers are ignored, they could potentially continue to hinder advancement, but if addressed, could help to unlock activity within this area and help speed up the transition to a fully circular product system.","Circular Design; Implementation; Industry perspectives; Products","en","book chapter","Walter de Gruyter","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-09-20","","","Circular Product Design","","",""
"uuid:da4b486b-147f-4a49-9f5c-aff762f0ad7c","http://resolver.tudelft.nl/uuid:da4b486b-147f-4a49-9f5c-aff762f0ad7c","A circular economy for medical devices; barriers and opportunities for laparoscopic instruments","Hoveling, T. (TU Delft Design for Sustainability); Faludi, Jeremy (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design)","","2023","","Circular Economy; Sustainable design; Medical Devices; Sustainable Healthcare; Laparoscopic devices","en","conference paper","International Care Electronics","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-11-11","","","Design for Sustainability","","",""
"uuid:c9cc6b52-73b5-4de5-bce1-0b50c659ea5b","http://resolver.tudelft.nl/uuid:c9cc6b52-73b5-4de5-bce1-0b50c659ea5b","Bio-based plastics in a circular economy: A review of recovery pathways and implications for product design","Ritzen, L. (TU Delft Circular Product Design); Sprecher, B. (TU Delft Design for Sustainability); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, A.R. (TU Delft Circular Product Design)","","2023","Bio-based plastics are attracting increasing attention due to their perceived sustainability and circularity. While enabling circularity by using renewable feedstocks, they still contribute to plastic pollution. Furthermore, their rapidly growing market will cause bio-based plastics to constitute significant fractions of plastic waste, necessitating efficient recovery at end-of-life. Technical overviews of potential recovery pathways for bio-based plastics exist, although these have not yet been translated into product design recommendations. In this article, we assess the impact of material composition and product design on the feasibility of eight recovery pathways for bio-based plastics. The ability to recover a plastic not only depends on the plastic composition, but also on the way a product is designed. The alterations made to tailor plastics to be applied in products, and the product architecture, can enable or prohibit some recovery pathways. The outcomes highlight the importance of establishing a wider range of recovery pathways for plastics, and the crucial role of product design in enabling a circular economy for bio-based plastics. We also present a first guidance for product design to enhance the recovery of bio-based plastics.","bio-based plastics; bio-based polymers; circular economy; end-of-life; recycling; product design","en","review","","","","","","","","","","","Circular Product Design","","",""
"uuid:89089bc8-c956-4c95-8fd5-ebe90762560f","http://resolver.tudelft.nl/uuid:89089bc8-c956-4c95-8fd5-ebe90762560f","Leveraging Transfer Learning in LSTM Neural Networks for Data-Efficient Burst Detection in Water Distribution Systems","Glynis, K.G. (TU Delft Sanitary Engineering; Royal HaskoningDHV); Kapelan, Z. (TU Delft Sanitary Engineering); Bakker, Martijn (Royal HaskoningDHV); Taormina, R. (TU Delft Sanitary Engineering)","","2023","Researchers and engineers employ machine learning (ML) tools to detect pipe bursts and prevent significant non-revenue water losses in water distribution systems (WDS). Nonetheless, many approaches developed so far consider a fixed number of sensors, which requires the ML model redevelopment and collection of sufficient data with the new sensor configuration for training. To overcome these issues, this study presents a novel approach based on Long Short-Term Memory neural networks (NNs) that leverages transfer learning to manage a varying number of sensors and retain good detection performance with limited training data. The proposed detection model first learns to reproduce the normal behavior of the system on a dataset obtained in burst-free conditions. The training process involves predicting flow and pressure one-time step ahead using historical data and time-related features as inputs. During testing, a post-prediction step flags potential bursts based on the comparison between the observations and model predictions using a time-varied error threshold. When adding new sensors, we implement transfer learning by replicating the weights of existing channels and then fine-tune the augmented NN. We evaluate the robustness of the methodology on simulated fire hydrant bursts and real-bursts in 10 district metered areas (DMAs) of the UK. For real bursts, we perform a sensitivity analysis to understand the impact of data resolution and error threshold on burst detection performance. The results obtained demonstrate that this ML-based methodology can achieve Precision of up to 98.1% in real-life settings and can identify bursts, even in data scarce conditions.","Burst detection; Deep learning; District metered areas; LSTM; Transfer learning","en","journal article","","","","","","","","","","","Sanitary Engineering","","",""
"uuid:874e2d2b-7508-4bcf-a9a6-1e5469a07af2","http://resolver.tudelft.nl/uuid:874e2d2b-7508-4bcf-a9a6-1e5469a07af2","Design of a syringe extension device (Chloe SED®) for low-resource settings in sub-Saharan Africa: a circular economy approach","Samenjo, K.T. (TU Delft Design for Sustainability; Nyanza Reproductive Health Society); Ramanathan, Aparna (Nyanza Reproductive Health Society; Georgetown University); Gwer, Stephen Otieno (Nyanza Reproductive Health Society; Maseno University); Bailey, Robert C. (Nyanza Reproductive Health Society; University of Illinois at Chicago); Otieno, Fredrick Odhiambo (Nyanza Reproductive Health Society); Koksal, Erin (Rethink Robotics); Sprecher, B. (TU Delft Design for Sustainability); Price, R.A. (TU Delft Marketing and Consumer Research); Bakker, C.A. (TU Delft Circular Product Design); Diehl, J.C. (TU Delft Design for Sustainability)","","2023","Underfunded healthcare infrastructures in low-resource settings in sub-Saharan Africa have resulted in a lack of medical devices crucial to provide healthcare for all. A representative example of this scenario is medical devices to administer paracervical blocks during gynaecological procedures. Devices needed for this procedure are usually unavailable or expensive. Without these devices, providing paracervical blocks for women in need is impossible resulting in compromising the quality of care for women requiring gynaecological procedures such as loop electrosurgical excision, treatment of miscarriage, or incomplete abortion. In that perspective, interventions that can be integrated into the healthcare system in low-resource settings to provide women needing paracervical blocks remain urgent. Based on a context-specific approach while leveraging circular economy design principles, this research catalogues the development of a new medical device called Chloe SED® that can be used to support the provision of paracervical blocks. Chloe SED®, priced at US$ 1.5 per device when produced in polypropylene, US$ 10 in polyetheretherketone, and US$ 15 in aluminium, is attached to any 10-cc syringe in low-resource settings to provide paracervical blocks. The device is designed for durability, repairability, maintainability, upgradeability, and recyclability to address environmental sustainability issues in the healthcare domain. Achieving the design of Chloe SED® from a context-specific and circular economy approach revealed correlations between the material choice to manufacture the device, the device's initial cost, product durability and reuse cycle, reprocessing method and cost, and environmental impact. These correlations can be seen as interconnected conflicting or divergent trade-offs that need to be continually assessed to deliver a medical device that provides healthcare for all with limited environmental impact. The study findings are intended to be seen as efforts to make available medical devices to support women's access to reproductive health services.","medical device design; context-driven design; circular economy; health and environment; low-resource settings; sub-Saharan Africa","en","journal article","","","","","","","","","","","Design for Sustainability","","",""
"uuid:792a85b8-1f32-4294-b667-3ea710e42d7a","http://resolver.tudelft.nl/uuid:792a85b8-1f32-4294-b667-3ea710e42d7a","Assessing the functional end of life of critical hydraulic structures in The Netherlands","Bakker, A.M.R. (TU Delft Hydraulic Structures and Flood Risk; Ministry of Infrastructure and Water Management); van Baaren, E.S. (Deltares); Hamerslag, E.J.F. (Ministry of Infrastructure and Water Management); Bodelier, C.J.J. (Student TU Delft)","Biondini, Fabio (editor); Frangopol, Dan M. (editor)","2023","Next decades, many hydraulic structures in the Netherlands will reach their end of life. Timely mitigation requires accurate estimates of the end of life. This appears however hard since many external drivers and multiple functions may lead in many plausible combinations to insufficient technical or functional performance. As a consequence, a complete integrated assessment is rather labour intensive and time consuming. This study shows a quick-scan of the end of life of five storm surge barriers and three other critical hydraulic structures in the Netherlands. The quick-scan reveals that sea-level rise is the major driver for the end of life of most coastal hydraulic structures since it impacts both the free discharge capacity and the flood protection function. Yet, the strategy to adapt the river delta to climate change may be even more important. Future developments are however such uncertain that the life time assessments may prove especially useful for the exploration of adaptive asset management strategies and to a lesser extent as an accurate planning tool.","","en","conference paper","Taylor and Francis","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:0f5a7fd0-173c-4d03-8390-d6f3d55a663f","http://resolver.tudelft.nl/uuid:0f5a7fd0-173c-4d03-8390-d6f3d55a663f","Embedding functional performance in asset management of hydraulic structures","Hamerslag, E.J.F. (Ministry of Infrastructure and Water Management); Bakker, A.M.R. (TU Delft Hydraulic Structures and Flood Risk; Ministry of Infrastructure and Water Management)","Biondini, Fabio (editor); Frangopol, Dan M. (editor)","2023","In the coming decades, the storm surge barriers in the Netherlands will reach their end of the designed life time of 100 years. Therefore, the Dutch storm surge barriers are preparing for major renovations. Next to this, as a result of the expected sea level rise, the hydraulic loads and the number of necessary closures will exceed the original design requirements. This gives urgency to look further than an one-to-one replacement or conservation and it a good moment to include changes in functional requirements. The functional end of life is, however, typically surrounded by large uncertainties. Since storm surge barriers bear multiple functions (e.g. hydraulic safety, the environment, shipping and road traffic infrastructure connection), changes in conditions can lead in several ways to the functional end of life. In this paper we explore what aspects should be added to current asset management strategy to include the functional performance of our hydraulic structures.","","en","conference paper","Taylor and Francis","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:8ccd9ebe-fd1a-45ed-a7fe-dda6dd59dd15","http://resolver.tudelft.nl/uuid:8ccd9ebe-fd1a-45ed-a7fe-dda6dd59dd15","Determining the future functional requirements of a pumping-weir station with the help of data-analysis","Van Gijzen, L. (TU Delft Hydraulic Structures and Flood Risk; Rijkswaterstaat); Bakker, A.M.R. (TU Delft Hydraulic Structures and Flood Risk; Rijkswaterstaat)","Biondini, Fabio (editor); Frangopol, Dan M. (editor)","2023","The pumping-weir complex at IJmuiden plays an important role in the drainage of excess water in the Western Netherlands. Multiple pumps need replacing as 4 out of 6 pumps near their end-of-life term. The optimal replacement strategy critically hinges on the future required pumping capacity. Yet, currently available models are not suited to assess the effect of sea level rise or extremer precipitation events as they ignore certain complexities of the water system. Preliminary data analysis in this paper showed the sensitivities of the system. The required pumping capacity is sensitive to the ability of free discharging during extreme water events. Yet, it is less susceptible to extremer precipitation events. Further research will aim at including more of the water system’s complexity in the model. Due to the node-like structure and high availability of data, a neural network modelling approach will probably be suitable.","","en","conference paper","Taylor and Francis","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:6b8c4ca5-8148-4cb3-95ec-8086c93c2f99","http://resolver.tudelft.nl/uuid:6b8c4ca5-8148-4cb3-95ec-8086c93c2f99","Gaia Data Release 3: The Galaxy in your preferred colours: Synthetic photometry from Gaia low-resolution spectra","Schultheis, M. (Université Côte d'Azur); Zhao, H. (Université Côte d'Azur); Zwitter, T. (University of Ljubljana); Hladczuk, N.A. (TU Delft Astrodynamics & Space Missions; European Space Astronomy Centre (ESAC)); Guerra, R. (European Space Astronomy Centre (ESAC)); Lammers, U. L. (European Space Astronomy Centre (ESAC)); Bakker, J. (European Space Astronomy Centre (ESAC)); Teodoro, P. de (European Space Astronomy Centre (ESAC)); García-Lario, P. (European Space Astronomy Centre (ESAC))","","2023","Gaia Data Release 3 provides novel flux-calibrated low-resolution spectrophotometry for '220 million sources in the wavelength range 330 nm ≤ λ ≤ 1050 nm (XP spectra). Synthetic photometry directly tied to a flux in physical units can be obtained from these spectra for any passband fully enclosed in this wavelength range. We describe how synthetic photometry can be obtained from XP spectra, illustrating the performance that can be achieved under a range of different conditions - for example passband width and wavelength range - as well as the limits and the problems affecting it. Existing top-quality photometry can be reproduced within a few per cent over a wide range of magnitudes and colour, for wide and medium bands, and with up to millimag accuracy when synthetic photometry is standardised with respect to these external sources. Some examples of potential scientific application are presented, including the detection of multiple populations in globular clusters, the estimation of metallicity extended to the very metal-poor regime, and the classification of white dwarfs. A catalogue providing standardised photometry for 2.2×108sources in several wide bands of widely used photometric systems is provided (Gaia Synthetic Photometry Catalogue; GSPC) as well as a catalogue of '105 white dwarfs with DA/non-DA classification obtained with a Random Forest algorithm (Gaia Synthetic Photometry Catalogue for White Dwarfs; GSPC-WD).","","en","journal article","","","","","","","","","","","Astrodynamics & Space Missions","","",""
"uuid:31c120f5-a467-4cd9-9722-b4a7649c17e1","http://resolver.tudelft.nl/uuid:31c120f5-a467-4cd9-9722-b4a7649c17e1","Gaia Data Release 3: Chemical cartography of the Milky Way","Schultheis, M. (Université Côte d'Azur); Zhao, H. (Université Côte d'Azur); Zwitter, T. (University of Ljubljana); Hladczuk, N.A. (TU Delft Astrodynamics & Space Missions; European Space Astronomy Centre (ESAC)); Guerra, R. (European Space Astronomy Centre (ESAC)); Lammers, U. L. (European Space Astronomy Centre (ESAC)); Bakker, J. (European Space Astronomy Centre (ESAC)); Teodoro, P. de (European Space Astronomy Centre (ESAC)); García-Lario, P. (European Space Astronomy Centre (ESAC))","","2023","Context. The motion of stars has been used to reveal details of the complex history of the Milky Way, in constant interaction with its environment. Nevertheless, to reconstruct the Galactic history puzzle in its entirety, the chemo-physical characterisation of stars is essential. Previous Gaia data releases were supported by a smaller, heterogeneous, and spatially biased mixture of chemical data from ground-based observations. Aims. Gaia Data Release 3 opens a new era of all-sky spectral analysis of stellar populations thanks to the nearly 5.6 million stars observed by the Radial Velocity Spectrometer (RVS) and parametrised by the GSP-Spec module. In this work, we aim to demonstrate the scientific quality of Gaia s Milky Way chemical cartography through a chemo-dynamical analysis of disc and halo populations. Methods. Stellar atmospheric parameters and chemical abundances provided by Gaia DR3 spectroscopy are combined with DR3 radial velocities and EDR3 astrometry to analyse the relationships between chemistry and Milky Way structure, stellar kinematics, and orbital parameters. Results. The all-sky Gaia chemical cartography allows a powerful and precise chemo-dynamical view of the Milky Way with unprecedented spatial coverage and statistical robustness. First, it reveals the strong vertical symmetry of the Galaxy and the flared structure of the disc. Second, the observed kinematic disturbances of the disc seen as phase space correlations and kinematic or orbital substructures are associated with chemical patterns that favour stars with enhanced metallicities and lower [α/Fe] abundance ratios compared to the median values in the radial distributions. This is detected both for young objects that trace the spiral arms and older populations. Several α, iron-peak elements and at least one heavy element trace the thin and thick disc properties in the solar cylinder. Third, young disc stars show a recent chemical impoverishment in several elements. Fourth, the largest chemo-dynamical sample of open clusters analysed so far shows a steepening of the radial metallicity gradient with age, which is also observed in the young field population. Finally, the Gaia chemical data have the required coverage and precision to unveil galaxy accretion debris and heated disc stars on halo orbits through their [α/Fe] ratio, and to allow the study of the chemo-dynamical properties of globular clusters. Conclusions. Gaia DR3 chemo-dynamical diagnostics open new horizons before the era of ground-based wide-field spectroscopic surveys. They unveil a complex Milky Way that is the outcome of an eventful evolution, shaping it to the present day.","","en","journal article","","","","","","","","","","","Astrodynamics & Space Missions","","",""
"uuid:5ca3cbe2-60a1-45f2-8f3d-230e2b45a236","http://resolver.tudelft.nl/uuid:5ca3cbe2-60a1-45f2-8f3d-230e2b45a236","Gaia Data Release 3: The extragalactic content","Schultheis, M. (Université Côte d'Azur); Zhao, H. (Université Côte d'Azur); Zwitter, T. (University of Ljubljana); Hladczuk, N.A. (TU Delft Astrodynamics & Space Missions; European Space Astronomy Centre (ESAC)); Guerra, R. (European Space Astronomy Centre (ESAC)); Lammers, U. L. (European Space Astronomy Centre (ESAC)); Bakker, J. (European Space Astronomy Centre (ESAC)); Teodoro, P. de (European Space Astronomy Centre (ESAC)); García-Lario, P. (European Space Astronomy Centre (ESAC))","","2023","The Gaia Galactic survey mission is designed and optimized to obtain astrometry, photometry, and spectroscopy of nearly two billion stars in our Galaxy. Yet as an all-sky multi-epoch survey, Gaia also observes several million extragalactic objects down to a magnitude of G 21 mag. Due to the nature of the Gaia onboard-selection algorithms, these are mostly point-source-like objects. Using data provided by the satellite, we have identified quasar and galaxy candidates via supervised machine learning methods, and estimate their redshifts using the low resolution BP/RP spectra. We further characterise the surface brightness profiles of host galaxies of quasars and of galaxies from pre-defined input lists. Here we give an overview of the processing of extragalactic objects, describe the data products in Gaia DR3, and analyse their properties. Two integrated tables contain the main results for a high completeness, but low purity (50-70%), set of 6.6 million candidate quasars and 4.8 million candidate galaxies. We provide queries that select purer sub-samples of these containing 1.9 million probable quasars and 2.9 million probable galaxies (both 95% purity). We also use high quality BP/RP spectra of 43 thousand high probability quasars over the redshift range 0.05-4.36 to construct a composite quasar spectrum spanning restframe wavelengths from 72 1000 nm.","","en","journal article","","","","","","","","","","","Astrodynamics & Space Missions","","",""
"uuid:f9844fe9-8e87-4865-954a-30ef1e3dedbe","http://resolver.tudelft.nl/uuid:f9844fe9-8e87-4865-954a-30ef1e3dedbe","Rocking of single-layer armour units measured by embedded sensors","Hofland, Bas (TU Delft Hydraulic Structures and Flood Risk); Houtzager, Daan (Reefy); Caldera, Ganga (Institut National de la Recherche Scientifique. Laval); Antonini, A. (TU Delft Coastal Engineering); van Gent, M.R.A. (TU Delft Coastal Engineering; Deltares); Bakker, Pieter (Delta Marine Consultants); van der Lem, Cock (Royal HaskoningDHV)","","2023","Single layer randomly placed armour units are used in many rubble mound breakwaters around the world. For these armour layers first extraction of units starts at high loads and can then progress quickly. Before the first extraction of a unit, typically no quantitative description of damage can be given. But additional to extraction, breakage of armour units due to rocking could be a major damage mechanism. This paper treat novel embedded Rocking Sensors. The technique is used to obtain the first measurements of rocking-impact velocities of single-layer units. They are also the first tests where the instrumented units can naturally move with the compacting layer during storm build-up. Physical model tests were performed on an armour layer with XBloc units. With 8 to 10 instrumented units per test run, in total 640 single measurements of the rocking motion of a unit during a 1200 wave test run were obtained, for three water levels and five wave heights. From the Rocking Sensors the number of impacts and rotational impact velocities were obtained. From an image analysis the along-slope settlement of the units during the tests was quantified. The rotational motion expressed by was found to be most convenient to express the motion. It can be seen that the units in the armour layer rock much more often than visually observed. Settlement seems to be a continuous progress, with most units rocking intermittently. Highest impact velocities are seen to occur around the water line, and in the uprush phase of the waves. A maximum impact velocity for all tests of 0.34 m/s (model scale) was measured. A preliminary design expression for rocking impact velocities of single layer units (Xblocs) is given. The paper shows that novel measurement techniques like the Rocking Sensors and vision techniques can and should be used to quantify damage mechanisms to rubble mound single-layer armour, additional to counting the extracted number of intact units.","rocking; armour units; breakwater; IMU sensor","en","journal article","","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:b67dc17d-aad4-47f1-910b-f36e44cda206","http://resolver.tudelft.nl/uuid:b67dc17d-aad4-47f1-910b-f36e44cda206","Wave field measurements of regular wave–monopile interaction using Free-Surface Synthetic Schlieren","Oldenziel, G. (TU Delft Fluid Mechanics; Deltares); Moreno-Rodenas, A. (Deltares); Bruinsma, N. (Deltares); Bakker, W. (Deltares)","","2023","Spatio-temporal wave patterns due to wave field–structure interaction can be very complex to measure and analyze when using (intrusive) point probes. Free-surface field measurements can offer much needed insight in this domain. Nevertheless, to the best of the authors’ knowledge, these methods are rarely used in experimental offshore engineering and research. In these fields, typical domain sizes are at least in the order of several m2, whereas (optical) free-surface field measurements are often not performed in domains with dimensions larger than roughly 0.5 × 0.5 m2. In the current work, the optical free-surface measurement technique named Free-Surface Synthetic Schlieren (FS-SS) is applied to measure the interaction between an incident wave field and a surface piercing cylinder, or monopile, in a domain of several m2 for the first time. The FS-SS method is validated for wave fields with wavelengths λ ≪ L to λ ≫ L, where L is the domain size in the direction of wave propagation. It is found that the incorporation of an additional water level measurement improves the agreement between intrusive wave height meters and the FS-SS measurement for large wavelengths (λ / L> 0.5) as compared to assuming a zero-mean free-surface. Wave field–monopile interaction is measured for two values of D/ λ: D/ λ= 0.1 and D/ λ= 0.2 , where D is the monopile diameter. For the case D/ λ= 0.2 the interaction wave field is analyzed by subtracting the measured wave field in the absence of a structure, from the measured interaction wave fields. The measured difference wave field reveals many interaction phenomena such as locations of amplification, both near the monopile and further away, a wake that has certain similarities with a Kelvin wake, and a circular small wavelength diffraction pattern. Additionally, the embedding of the measurements in a wave breaking regime map is presented. In this map, the applicability for certain wave conditions can be clearly visualized. It is concluded that the FS-SS method, including the proposed improvement using additional sensor data, is a useful addition to the toolbox of hydraulic engineers and researchers, and that especially the measured locations of wave amplification in the far field will not be easily detected using (arrays of) point probes.","","en","journal article","","","","","","","","","","","Fluid Mechanics","","",""
"uuid:8faa9aad-c3cf-4f81-b766-0e7362b54e51","http://resolver.tudelft.nl/uuid:8faa9aad-c3cf-4f81-b766-0e7362b54e51","Inter-Organizational Collaboration in Interconnected Infrastructure Projects","de Bruijne, M.L.C. (TU Delft Organisation & Governance); Hertogh, M.J.C.M. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management); Rikhtegarnezami, M. (TU Delft Integral Design & Management)","","2023","This study aims to identify which factors affect inter-organizational collaboration (IOC) in interconnected infrastructure projects to enable practitioners to establish a collaborative environment at the project level. This specific form of inter-organizational collaboration (IOC) is characterized as “horizontal” and has received limited attention in the literature. To this end, a systematic literature review and Q-methodology were conducted. The Q-methodology involves practitioners from various infrastructure organizations in the Netherlands gaining insights into their perspectives on IOC in interconnected infrastructure projects. The study identifies two perspectives: a “holistic, goal-oriented” perspective that recognizes various dimensions of IOC and a more “people-oriented” perspective that emphasizes the value of individual factors for IOC. The findings suggest that multiple perspectives on collaboration exist among practitioners, potentially affecting collaboration in interconnected infrastructure projects. Awareness of the need to manage practitioners’ perspectives, and addressing and discussing these differences, can stimulate inter-organizational collaboration and contribute to improved project performance.","inter-organizational collaboration; collaboration factors; interconnected infrastructure projects","en","journal article","","","","","","","","","","","Organisation & Governance","","",""
"uuid:03720c24-b1d2-4d2e-8130-8e9208fe3ad1","http://resolver.tudelft.nl/uuid:03720c24-b1d2-4d2e-8130-8e9208fe3ad1","Economic optimization of coastal flood defence systems including storm surge barrier closure reliability","Mooyaart, L.F. (TU Delft Hydraulic Structures and Flood Risk; Rijkswaterstaat); Bakker, A.M.R. (TU Delft Hydraulic Structures and Flood Risk; Rijkswaterstaat); van den Bogaard, Johan A. (Rijkswaterstaat); Rijcken, T. (TU Delft Hydraulic Structures and Flood Risk); Jonkman, Sebastiaan N. (TU Delft Hydraulic Structures and Flood Risk; Texas A&M University at Galveston)","","2023","Storm surge barriers are large movable hydraulic structures which close during a storm surge to prevent coastal floods. In the regions they protect, a failure to close the barrier is often the most likely cause for a catastrophic flood. Nevertheless, flood risk assessments usually only focus on raising flood defences behind the barrier. Despite its importance, there is no general method to assess the costs and benefits of improving the closure reliability. This paper presents a model that optimises investments considering both closure reliability improvements and raising flood defences behind the barrier, using the region protected by the Maeslant barrier as a case. We substantiate that constructing the Maeslant barrier was an optimal economic decision. Moreover, we demonstrate large investments such as a redundant barrier already being economically sound with a few decimetres of sea level rise. Based on our experience with this case study, we expect the model is useful in finding strategies to adapt to rising sea levels and other developments that cause coastal flood risk to rise worldwide.","economic optimization; flood defence; flood risk; reliability; storm surge barrier","en","journal article","","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:5581e477-3193-4fca-b16a-b109ae88f1f5","http://resolver.tudelft.nl/uuid:5581e477-3193-4fca-b16a-b109ae88f1f5","Flow and Flourishing During the Pandemic: The Roles of Strengths Use and Playful Design","Liu, Wei (TU Delft Design Aesthetics); Zhang, Wen (Beijing Normal University); van der Linden, Dimitri (Erasmus Universiteit Rotterdam); Bakker, Arnold B. (Erasmus Universiteit Rotterdam; University of Johannesburg)","","2023","Ruminative thoughts induced by the COVID-19 pandemic have an adverse impact on individual well-being. However, little is known about how to alleviate such a negative effect – let alone how a person can flourish during crises. The current study uses the self-determination model of flow to propose that two proactive behaviors, strength use and playful design, are positively related to the flow experience, which, in turn, is positively related to daily flourishing. Moreover, we propose that the effects of proactive behaviors on flow are stronger when individuals ruminate more about COVID-19 pandemic. Using a day reconstruction method, we collected data from university students across five consecutive days (N-person = 135, N-day = 665, N-activity = 2985). Multilevel results showed that strengths use and playful design were positively related to flow experience. In turn, flow experience was positively related to daily flourishing. Moreover, we found that COVID-19 rumination moderated the associations between proactive behaviors and flow, such that strengths use and playful design were more effective to foster flow when individuals had a higher (vs. lower) level of rumination. The results imply that in order to function well and flourish during a crisis, individuals could make use of their strengths or playfully design the activities in their daily lives. In a broader sense, we provide concrete behavioral strategies to cope with the downsides of negative events.","COVID-19 rumination; Flourishing; Flow; Playful design; Strengths use","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2024-01-19","","","Design Aesthetics","","",""
"uuid:ec523c08-c21a-44ca-a79b-abf34f10f7dd","http://resolver.tudelft.nl/uuid:ec523c08-c21a-44ca-a79b-abf34f10f7dd","Impact of the Current on Reverse Bias Degradation of Perovskite Solar Cells","Henzel, J. (TU Delft Photovoltaic Materials and Devices; TNO); Bakker, N.J. (TNO); Najafi, Mehrdad (TNO); Zardetto, Valerio (TNO); Veenstra, Sjoerd (TNO); Isabella, O. (TU Delft Photovoltaic Materials and Devices); Mazzarella, L. (TU Delft Photovoltaic Materials and Devices); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; TNO); Theelen, Mirjam (TNO)","","2023","Nonequal current generation in the cells of a photovoltaic module, e.g., due to partial shading, leads to operation in reverse bias. This quickly causes a significant efficiency loss in perovskite solar cells. We report a more quantitative investigation of the reverse bias degradation. Various small reverse biases (negative voltages) were applied for different durations. After normalizing the applied voltages with the breakdown voltages, we found similar dependences of the reverse bias current and the degradation rate. We draw conclusions regarding possible degradation mechanisms and propose a way to increase the comparability of degradation rates for comparing different perovskite solar cells.","degradation; negative voltages; partial shading; perovskite solar cells; reverse bias; stability","en","journal article","","","","","","","","","","","Photovoltaic Materials and Devices","","",""
"uuid:2dc3a831-8f73-42ed-9b46-0a4e3e6cfea8","http://resolver.tudelft.nl/uuid:2dc3a831-8f73-42ed-9b46-0a4e3e6cfea8","Conceptualising a Circular Economy—an Enquiry into Circular Economy Conceptual Metaphors","Fromberg, E.H.E. (TU Delft Design for Sustainability; The University of Cambridge Institute for Sustainability Leadership, Cambridge); Bakker, C.A. (TU Delft Circular Product Design); Peck, David (TU Delft Environmental & Climate Design)","","2023","Numerous academic scholars argue for a radical transformation of the economy towards a circular model, in response to pressures from planetary and social issues such as energy, climate change, inequality, and resource depletion. This study examines how the academic community perceives the concept of a circular economy in comparison to traditional economic discourse, through the lens of conceptual metaphors. Conceptual metaphors are systematic properties that reflect one’s understanding of abstract phenomena like a circular economy. Through a structured review of the literature, seven dominant conceptual metaphors were identified that shape the understanding of traditional economics. The study also conducted a textual analysis of the ten most frequently cited academic papers on the circular economy. The analysis revealed that certain dominant metaphors from traditional economics have been influential in shaping discourse on the circular economy. The most common metaphors were the machine metaphor, competitive metaphors, the journey metaphor, and ecological metaphors. Each conceptual metaphor has its own strengths and weaknesses, which may include poorly explained areas or missing dimensions. These two aspects are referred to as misconceptions and blind spots, respectively, and the paper reflects on the implications of these for the current academic discourse on the circular economy.","Circular economy; Conceptual metaphor theory; Rhetoric","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2024-06-06","","","Design for Sustainability","","",""
"uuid:2891e2d5-523b-4795-96ae-c3b3199c96c8","http://resolver.tudelft.nl/uuid:2891e2d5-523b-4795-96ae-c3b3199c96c8","Gaia Data Release 3: Summary of the content and survey properties","Hladczuk, N.A. (TU Delft Astrodynamics & Space Missions); Brown, Anthony (Universiteit Leiden); Bakker, J. (European Space Astronomy Centre); Benson, K. (MSSL/UCL); Janßen, Katja; Jordan, Stefan (Astronomisches Rechen-Institut Heidelberg); Löffler, W. (Astronomisches Rechen-Institut Heidelberg); Marchal, Olivier (Observatoire Astronomique de Strasbourg); Sarro, Luis Manuel (Dpto. de Inteligencia Artificial); Aerts, Conny (Max-Planck-Institut für Astronomie; Katholieke Universiteit Leuven; Radboud Universiteit Nijmegen); David, Marc (Universiteit Antwerpen); Gomez, A. (Universidade da Coruña); Helmer, A. (CNES Centre National d'Etudes Spatiales); Holland, G. (University of Cambridge); Liao, S. (Radio Observatory Medicina; University of Chinese Academy of Sciences); Marcos, J. (European Space Agency (ESA)); Mor, Roger (Universitat Politecnica de Catalunya); Morris, D.; Murphy, C. P. (European Space Astronomy Centre); Nagy, Z. (Hungarian Academy of Sciences); Weiler, M. (Universitat Politecnica de Catalunya); Wevers, T. (University of Cambridge; European Southern Observatory (ESO)); Zhao, He (Laboratoire Lagrange)","","2023","Context. We present the third data release of the European Space Agency's Gaia mission, Gaia DR3. This release includes a large variety of new data products, notably a much expanded radial velocity survey and a very extensive astrophysical characterisation of Gaia sources. Aims. We outline the content and the properties of Gaia DR3, providing an overview of the main improvements in the data processing in comparison with previous data releases (where applicable) and a brief discussion of the limitations of the data in this release. Methods. The Gaia DR3 catalogue is the outcome of the processing of raw data collected with the Gaia instruments during the first 34 months of the mission by the Gaia Data Processing and Analysis Consortium. Results. The Gaia DR3 catalogue contains the same source list, celestial positions, proper motions, parallaxes, and broad band photometry in the G, GBP, and GRP pass-bands already present in the Early Third Data Release, Gaia EDR3. Gaia DR3 introduces an impressive wealth of new data products. More than 33 million objects in the ranges GRVS'<'14 and 3100'<'Teff'<'14'500, have new determinations of their mean radial velocities based on data collected by Gaia. We provide GRVS magnitudes for most sources with radial velocities, and a line broadening parameter is listed for a subset of these. Mean Gaia spectra are made available to the community. The Gaia DR3 catalogue includes about 1 million mean spectra from the radial velocity spectrometer, and about 220 million low-resolution blue and red prism photometer BP/RP mean spectra. The results of the analysis of epoch photometry are provided for some 10 million sources across 24 variability types. Gaia DR3 includes astrophysical parameters and source class probabilities for about 470 million and 1500 million sources, respectively, including stars, galaxies, and quasars. Orbital elements and trend parameters are provided for some 800'000 astrometric, spectroscopic and eclipsing binaries. More than 150'000 Solar System objects, including new discoveries, with preliminary orbital solutions and individual epoch observations are part of this release. Reflectance spectra derived from the epoch BP/RP spectral data are published for about 60 000 asteroids. Finally, an additional data set is provided, namely the Gaia Andromeda Photometric Survey, consisting of the photometric time series for all sources located in a 5.5 degree radius field centred on the Andromeda galaxy. Conclusions. This data release represents a major advance with respect to Gaia DR2 and Gaia EDR3 because of the unprecedented quantity, quality, and variety of source astrophysical data. To date this is the largest collection of all-sky spectrophotometry, radial velocities, variables, and astrophysical parameters derived from both low- and high-resolution spectra and includes a spectrophotometric and dynamical survey of SSOs of the highest accuracy. The non-single star content surpasses the existing data by orders of magnitude. The quasar host and galaxy light profile collection is the first such survey that is all sky and space based. The astrophysical information provided in Gaia DR3 will unleash the full potential of Gaia's exquisite astrometric, photometric, and radial velocity surveys.","Astrometry; Catalogs; Parallaxes; Techniques: photometric; Techniques: radial velocities; Techniques: spectroscopic","en","journal article","","","","","","","","","","","Astrodynamics & Space Missions","","",""
"uuid:2a70a853-e797-485e-a3af-d972fff41336","http://resolver.tudelft.nl/uuid:2a70a853-e797-485e-a3af-d972fff41336","Antecedents and outcomes of work-related flow: A meta-analysis","Liu, Wei (TU Delft Design Aesthetics); Lu, Hairong (Erasmus Universiteit Rotterdam); Li, Peikai (Universiteit Gent); van der Linden, Dimitri (Erasmus Universiteit Rotterdam); Bakker, A.B. (Erasmus Universiteit Rotterdam; University of Johannesburg)","","2023","Flow is an optimal state that contributes positively to individual well-being and performance. Despite growing evidence of its antecedents and outcomes at work, few efforts have been made to systematically examine and synthesize the extant findings to advance the theoretical and empirical development of flow. Combining different perspectives (e.g., job demands and resources theory, proactivity and leadership literatures), we aim to identify the key antecedents and outcomes relevant to work-related flow, and (a) provide a nomological network and (b) spot areas for future research on flow. We conducted a meta-analysis to synthesize findings (N = 60,110, k = 113). Results showed that several factors, including job characteristics, individual characteristics, individual behaviors, and leadership characteristics were significantly related to flow. Individual behavior displayed the strongest association with flow (ρ = 0.55). In addition, flow was not only related to job outcomes but also to personal outcomes. We also investigated the relative contribution of sub-dimensions of flow to well-being and performance. The relationships between flow and its associates hold across different measures of flow and culture. Our findings suggest that employees can use more proactive strategies to foster flow rather than only respond to their environment. Despite the short-run side effects of flow (e.g., risk-taking behavior), flow is worth pursuing in the long run as it benefits both work and personal well-being. We encourage future flow studies to investigate additional social and situational factors and various types of proactive behaviors in a multilevel process.","Job demands; Job resources; Meta-analysis; Proactive behaviors; Well-being; Work-related flow","en","journal article","","","","","","","","","","","Design Aesthetics","","",""
"uuid:6490fe54-db21-47c2-b79a-4c960e6b7f1a","http://resolver.tudelft.nl/uuid:6490fe54-db21-47c2-b79a-4c960e6b7f1a","Gaia Data Release 3: Exploring and mapping the diffuse interstellar band at 862 nm","Schultheis, M. (Université Côte d'Azur); Zhao, H. (Université Côte d'Azur); Zwitter, T. (University of Ljubljana); Hladczuk, N.A. (TU Delft Astrodynamics & Space Missions; European Space Astronomy Centre (ESAC)); Guerra, R. (European Space Astronomy Centre (ESAC)); Lammers, U. L. (European Space Astronomy Centre (ESAC)); Bakker, J. (European Space Astronomy Centre (ESAC)); Teodoro, P. de (European Space Astronomy Centre (ESAC)); García-Lario, P. (European Space Astronomy Centre (ESAC))","","2023","Context. Diffuse interstellar bands (DIBs) are common interstellar absorption features in spectroscopic observations but their origins remain unclear. DIBs play an important role in the life cycle of the interstellar medium (ISM) and can also be used to trace Galactic structure. Aims. Here, we demonstrate the capacity of the Gaia-Radial Velocity Spectrometer (RVS) in Gaia DR3 to reveal the spatial distribution of the unknown molecular species responsible for the most prominent DIB at 862 nm in the RVS passband, exploring the Galactic ISM within a few kiloparsecs from the Sun. Methods. The DIBs are measured within the GSP-Spec module using a Gaussian profile fit for cool stars and a Gaussian process for hot stars. In addition to the equivalent widths and their uncertainties, Gaia DR3 provides their characteristic central wavelength, width, and quality flags. Results. We present an extensive sample of 476 117 individual DIB measurements obtained in a homogeneous way covering the entire sky. We compare spatial distributions of the DIB carrier with interstellar reddening and find evidence that DIB carriers are present in a local bubble around the Sun which contains nearly no dust. We characterised the DIB equivalent width with a local density of 0.19 ± 0.04 kpc1 and a scale height of 98.60 8.46+11.10 pc. The latter is smaller than the dust scale height, indicating that DIBs are more concentrated towards the Galactic plane. We determine the rest-frame wavelength with unprecedented precision (?0 = 8620.86 ± 0.019 in air) and reveal a remarkable correspondence between the DIB velocities and the CO gas velocities, suggesting that the 862 nm DIB carrier is related to macro-molecules. Conclusions. We demonstrate the unique capacity of Gaia to trace the spatial structure of the Galactic ISM using the 862 nm DIB.","","en","journal article","","","","","","","","","","","Astrodynamics & Space Missions","","",""
"uuid:59c894b1-9b25-41f3-ba7d-21356ffa49a1","http://resolver.tudelft.nl/uuid:59c894b1-9b25-41f3-ba7d-21356ffa49a1","A policy framework for the circular economy: Lessons from the EU","Hartley, Kris (City University of Hong Kong); Schülzchen, S. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Kirchherr, J.W. (Universiteit Utrecht; Roskilde University; University of Cambridge)","","2023","Transitioning from the ‘take-make-dispose’ linear production system to a circular economy can strengthen sustainability, and governments play a vital role. Recent scholarship has investigated policies for circular economy transition, but few studies take a perspective on circularity reform that spans geographies, industries, and product life-cycle stages. This article fills that gap by introducing a policy framework for the circular economy that includes over 100 policy instruments. The framework is developed from a review of 572 studies published in the academic and grey literature, along with policy databases and other documents. The findings are validated and supplemented by data from 33 semi-structured interviews with circular economy experts including scholars, policymakers, and representatives from NGOs and businesses. Derived primarily from the EU context but broadly applicable, the framework categorizes circular economy policies into nine groups. Six groups correspond to stages of the product life-cycle and three are overarching, capturing a holistic perspective mostly lacking in the literature. This study aims to promote a more structured discussion about circular economy policies and provides directions for future research by identifying topics where scholarship is thin. In addition to advancing theory, the framework can also serve as an assessment lens for designing circular economy policies.","Circular economy; Industrial ecology; Public policy; Regulation; Resource efficiency; Sustainability transition","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-11-11","","","Circular Product Design","","",""
"uuid:9d5c8743-b6ad-44f6-b06f-cd122f6ec15e","http://resolver.tudelft.nl/uuid:9d5c8743-b6ad-44f6-b06f-cd122f6ec15e","Evaluating building circularity in the early design phase","van der Zwaag, Marco (Student TU Delft); Wang, T. (TU Delft Design & Construction Management); Bakker, H.L.M. (TU Delft Integral Design & Management); van Nederveen, G.A. (TU Delft Integral Design & Management); Schuurman, A.C.B. (TU Delft Applied Mechanics); Bosma, Douwe (Bam infra)","","2023","Facing circular transition challenges, building circularity should be evaluated in the early design phase to reduce the risks of circular and environmental performance problems found in later project phases. However, due to the current design workflow, such practice is hindered because there is not enough information to evaluate building circularity in detail in the early design phases. An improved workflow to emphasize circularity more in the early design phase is thus needed. This research explores the current workflow and designs an improved workflow by developing an automated decision support system to assess early design phase building circularity with limited available information, aiming to improve the working efficiency and efficacy. This automated system helps in data-driven decision-making by integrating different data sources and presenting the calculated results interactively with business intelligence interfaces. The interfaces involve different types of evaluations based on the data availability in both schematic design and detail design sub-phases. It also visualizes the data quality and future scenarios. This system has been designed based on interviews and literature studies, and verified and validated with practitioners. This study serves as a starting point to rethink the workflow to improve circularity with currently available technology.","Building circularity index; Building information modelling; Circular design workflow; Decision support system; Evaluation tool; Material circularity indicator","en","journal article","","","","","","","","","","","Design & Construction Management","","",""
"uuid:5ea608fd-5428-4093-b2e4-c8ff0ab6c574","http://resolver.tudelft.nl/uuid:5ea608fd-5428-4093-b2e4-c8ff0ab6c574","New Guidelines for the Quality Control of Risk Analyses of Critical Hydraulic Structures","Bakker, A.M.R. (TU Delft Hydraulic Structures and Flood Risk; Ministry of Infrastructure and Water Management); Busnach, Tycho (Ministry of Infrastructure and Water Management); Mooyaart, L.F. (TU Delft Hydraulic Structures and Flood Risk); Van Gijzen, L. (TU Delft Hydraulic Structures and Flood Risk; Ministry of Infrastructure and Water Management)","Brito, Mario P. (editor); Aven, Terje (editor); Baraldi, Piero (editor); Cepin, Marko (editor); Zio, Enrico (editor)","2023","The efficacy of risk models and risk analyses critically hinges on sufficient model evaluation. Nevertheless, the usefulness for the intended purpose is rarely systematically assessed. Poor or even lacking model evaluation of the applied risk models and analyses also troubles the asset management of storm surge barriers in the Netherlands. In practice, obvious flaws, missing failure modes and use that deviates from the original purpose regularly lead to unpleasant surprises, unnecessary costs and avoidable risks.
Here, we introduce new guidelines for the quality control during the development, testing, maintenance and usage of risk analyses of critical hydraulic structures.
First responses among stakeholders are rather positive since the guidelines help modelers and analysts to better understand critics and independent reviewers to structure their comments. However, the efficacy of the guidelines itself also need rigorous evaluation in the coming years. This may prove challenging as the application of the guidelines may also reveal that the organizations that operation the storm surge barriers are currently insufficiently equipped for the rigorous quality control of risk models and risk analyses.","risk analysis; model quality assessment; model validation; model evaluation; storm surge barriers; hydraulic structures","en","conference paper","Research Publishing","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2024-03-08","","","Hydraulic Structures and Flood Risk","","",""
"uuid:04bd80f4-1f95-483a-8e78-d84fad722201","http://resolver.tudelft.nl/uuid:04bd80f4-1f95-483a-8e78-d84fad722201","A Systematic Approach to Improve Reliability of Storm Surge Barrier Closures","Mooyaart, L.F. (TU Delft Hydraulic Structures and Flood Risk); Bakker, A.M.R. (Rijkswaterstaat); van den Bogaard, J.A. (Rijkswaterstaat); Jonkman, Sebastiaan N. (TU Delft Hydraulic Structures and Flood Risk)","Brito, Mario P. (editor); Aven, Terje (editor); Baraldi, Piero (editor); Cepin, Marko (editor); Zio, Enrico (editor)","2023","Coastal defenses must be upgraded to combat increasing flood risk due to climate change and other factors. Storm surge barriers, large movable hydraulic structures that close temporarily during storm surges to prevent coastal floods, play a vital role in protecting estuaries. Due to the complexity of their risk analyses, important improvements are sometimes overseen. Our objective is to develop a systematic approach which is more likely to find these important improvements. We tested the method to three historic cases where important improvements were initially overlooked. We anticipate that our method can be applied to other safety systems with a large number of failure modes as well.","Climate change adaptation; risk reduction measures; coastal flood; safety system","en","conference paper","Research Publishing","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2024-03-08","","","Hydraulic Structures and Flood Risk","","",""
"uuid:fb754a02-6f1b-4371-88cc-66725bbe9a52","http://resolver.tudelft.nl/uuid:fb754a02-6f1b-4371-88cc-66725bbe9a52","Effect of a singular planar heterogeneity on tensile failure","Pluymakers, Anne (TU Delft Applied Geophysics and Petrophysics); Bakker, R.R. (TU Delft Reservoir Engineering); Ter Steege, F.B. (Student TU Delft); Versluis, B. (Student TU Delft); Barnhoorn, A. (TU Delft Applied Geophysics and Petrophysics)","","2023","Many rocks contain planar heterogeneities, in the form of open fractures, veins and/or stylolites, but scarce data exist on how strength and fracture pattern formation is affected by the presence of a singular planar heterogeneity in an otherwise uniform matrix. The mechanics of stylolite-bearing and/or fractured limestone is of interest to several engineering applications, from quarries to subsurface gas or geothermal reservoirs. We have performed Brazilian Disc tests on pre-fractured Indiana limestone samples and Treuchtlinger Marmor discs which contain cohesive stylolites, investigating Brazilian test Strength and the resulting fracture pattern. All experiments were filmed, and where possible analyzed with particle image velocimetry. When viewed in 2D, the planar discontinuity was set at different rotation angles compared to the principal loading direction, where perpendicular to the loading direction is defined as 0⁰. The results show that all samples are weaker than their intact counterparts. For the pre-fractured Indiana limestone, there is 10–75% angle-dependent weakening. However, in the samples with a stylolite, strength is weakened by 35–75%, independent of direction. Several new cracks appeared when fracturing a stylolite-sample, where the orientation is heavily influenced by the stylolite orientation. The fracture pattern and associated stress drops are more complex for high angles. In these samples always more than one fracture formed, whereas in pre-fractured samples usually only one new fracture formed. This suggests a potential for more permeability increase when hydrofracturing a stylolite-rich interval. Comparison with Finite Element Models indicates that this difference in fracture pattern is caused by the strength contrast between the anastomosing stylolite zone and the matrix material, leading to stress concentrations effects. This causes (micro-) fracture nucleation to occur locally, promotes fracture coalescence and fracture growth at lower overall sample-load conditions compared to intact samples.","Anisotropy; Fracture; Heterogeneity; Limestone; Stylolite; Tensile strength","en","journal article","","","","","","","","","","","Applied Geophysics and Petrophysics","","",""
"uuid:8c8e4084-94fd-4766-b93f-22bc5c7f7348","http://resolver.tudelft.nl/uuid:8c8e4084-94fd-4766-b93f-22bc5c7f7348","Productontwerp in een Circulaire Economie","Bakker, C.A. (TU Delft Circular Product Design)","","2022","Dit rapport is tot stand gekomen in het kader van het Werkprogramma Monitoring enSturing Circulaire Economie 2019-2023","","nl","report","Technische Universiteit Delft","","","","","External Report","","","","","Circular Product Design","","",""
"uuid:c8015b17-9a3d-4da2-a3b2-c9e71325e2d5","http://resolver.tudelft.nl/uuid:c8015b17-9a3d-4da2-a3b2-c9e71325e2d5","Review: Horizontal, directionally drilled and radial collector wells: Pozos horizontales y colectores radiales de perforación direccional","Houben, Georg J. (Federal Institute for Geosciences and Natural Resources); Collins, Sarah (British Geological Survey); Bakker, M. (TU Delft Water Resources); Daffner, Thomas (Umweltbüro GmbH Vogtland, Weischlitz); Triller, Falk (Bohrlochmessung Storkow GmbH, Storkow); Kacimov, Anvar (Sultan Qaboos University, Muscat)","","2022","Horizontal wells play an often overlooked role in hydrogeology and aquifer remediation but can be an interesting option for many applications. This study reviews the constructional and hydraulic aspects that distinguish them from vertical wells. Flow patterns towards them are much more complicated than those for vertical wells, which makes their mathematical treatment more demanding. However, at some distance, the drawdown fields of both well types become practically identical, allowing simplified models to be used. Due to lower drawdowns, the yield of a horizontal well is usually higher than that of a vertical well, especially in thin aquifers of lower permeability, where they can replace several of the latter. The lower drawdown, which results in lower energy demand and slower ageing, and the centralized construction of horizontal wells can lead to lower operational costs, which can make them an economically feasible option.","Drilling; Horizontal well; Radial collector well; Slant well; Water supply","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:23e1c0e1-6f6c-4d86-a508-c415b0049aa7","http://resolver.tudelft.nl/uuid:23e1c0e1-6f6c-4d86-a508-c415b0049aa7","A Storytelling Methodology to Facilitate User-Centered Co-Ideation between Scientists and Designers","Talgorn, E.C.V. (TU Delft Design for Sustainability; Philips Research); Hendriks, Monique (Philips Research; Eindhoven University of Technology); Geurts, Luc (Philips Research); Bakker, C.A. (TU Delft Circular Product Design)","","2022","Successful implementation of sustainable innovation requires strong collaborative ecosys-tems. In particular, collaboration between scientific and people-centered expertise (e.g., designers) is essential to bring technical innovation through contextualized, meaningful and attractive experiences. However, in practice, these types of expertise are siloed and struggle to communicate and think together. We present a creative design method based on participatory story building to support collaborative user-centered ideation between technology scientists and designers. The core of the method is a new story creation model, the three-tension framework, that facilitates the exploration of users’ experiences and needs during ideation. To evaluate the method’s effectiveness, we conducted open-ended interviews with participants. We found that the method facilitates the expression of different perspectives and outside-the-box creative thinking. An originality and strength of our method is that it favors the discovery of new issues and pain points—rather than only solutions. This, combined with idea enrichment by multidisciplinary expertise, contributes to generating ideas in a broader range of application areas than usual. Our results indicate that participatory storytelling has the potential to facilitate multidisciplinary collaboration and to bring user-centered thinking to non-design stakeholders in order to envision user needs in future scenarios and new ecosystems.","co-creation; multidisciplinary; storytelling; sustainable user-centered innovation","en","journal article","","","","","","","","","","","Design for Sustainability","","",""
"uuid:68adca48-691a-49d7-b8c1-42d89f17bba9","http://resolver.tudelft.nl/uuid:68adca48-691a-49d7-b8c1-42d89f17bba9","Application of Time Series Analysis to Estimate Drawdown From Multiple Well Fields","Brakenhoff, Davíd A. (Artesia B.V.); Vonk, M.A. (TU Delft Water Resources; Artesia B.V.); Collenteur, Raoul A. (Graz University of Technology); Van Baar, Marco (Artesia B.V.); Bakker, M. (TU Delft Water Resources)","","2022","In 2018–2020, meteorological droughts over Northwestern Europe caused severe declines in groundwater heads with significant damage to groundwater-dependent ecosystems and agriculture. The response of the groundwater system to different hydrological stresses is valuable information for decision-makers. In this paper, a reproducible, data-driven approach using open-source software is proposed to quantify the effects of different hydrological stresses on heads. A scripted workflow was developed using the open-source Pastas software for time series modeling of heads. For each head time series, the best model structure and relevant hydrological stresses (rainfall, evaporation, river stages, and pumping at one or more well fields) were selected iteratively. A new method was applied to model multiple well fields with a single response function, where the response was scaled by the distances between the pumping and observation wells. Selection of the best model structure was performed through reliability checking based on four criteria. The time series model of each observation well represents an independent estimate of the contribution of different hydrological stresses to the head and is based exclusively on observed data. The approach was applied to estimate the drawdown caused by nearby well fields to 250 observed head time series measured at 122 locations in the eastern part of the Netherlands, a country where summer droughts can cause problems, even though the country is better known for problems with too much water. Reliable models were obtained for 126 head time series of which 78 contain one or more well fields as a contributing stress. The spatial variation of the modeled responses to pumping at the well fields show the expected decline with distance from the well field, even though all responses were modeled independently. An example application at one well field showed how the head response to pumping varies per aquifer. Time series analysis was used to determine the feasibility of reducing pumping rates to mitigate large drawdowns during droughts, which depends on the magnitude and response time of the groundwater system to changes in pumping. This is salient information for decision-makers. This article is part of the special issue “Rapid, Reproducible, and Robust Environmental Modeling for Decision Support: Worked Examples and Open-Source Software Tools”.","time series analysis; well drawdown; groundwater; decision support; reproducible; model selection; Hantush response function","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:fce4b6af-ac6b-4601-bb5c-843a0062491a","http://resolver.tudelft.nl/uuid:fce4b6af-ac6b-4601-bb5c-843a0062491a","On the fundamental solutions-based inversion of Laplace matrices","Vermolen, F.J. (TU Delft Numerical Analysis; University of Hasselt); Bakker, D.R. (Student TU Delft); Vuik, Cornelis (TU Delft Delft Institute of Applied Mathematics)","","2022","The discretisation of the Laplacian results into the well-known Laplace matrix. In the case of a one dimensional problem, an explicit formula for its inverse is derived on the basis of fundamental solutions (Green’s functions) for general boundary conditions. For a linear reaction–diffusion equation, approximations of the inverse are given.","Inverse matrix; Laplace matrix; Finite element discretisation; Fundamental solutions","en","journal article","","","","","","","","","","","Numerical Analysis","","",""
"uuid:ad067a26-9c4e-4fee-9612-1b2b41db7bab","http://resolver.tudelft.nl/uuid:ad067a26-9c4e-4fee-9612-1b2b41db7bab","Fundamental Mechanisms Behind the Reverse Characteristic of Cu(In,Ga)Se2 Solar Cells","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices; TNO); Assen, Suzanne (TNO); Rasia, Alix (TNO); Barreau, Nicolas (Université de Nantes); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; TNO); Theelen, Mirjam (TNO)","","2022","Partial shading of PV modules can lead to degradation of the shaded cells. The degradation originates from a reverse bias voltage over the shaded cells. In order to mitigate reverse bias damage in Cu(In, Ga)Se2 (CIGS) modules, a good understanding of the fundamental mechanisms governing the reverse characteristic is required. In this study, a model is introduced that describes this behavior for CIGS cells. In this model, the low and non-Ohmic leakage current is accounted for by the space charge limited current component. A sharp increase in current that is typically observed in the CIGS reverse characteristics can be described by Fowler-Nordheim tunneling. This model has been validated against measurements performed at different temperatures and illumination intensities, and is able to describe the dependencies of the reverse bias behavior on both temperature and illumination.","Cu(In,Ga)Se2 (CIGS); partial shading; reverse bias; thin-film PV","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-07-01","","","Photovoltaic Materials and Devices","","",""
"uuid:2af25ba4-a693-4c36-8477-af6d218433c8","http://resolver.tudelft.nl/uuid:2af25ba4-a693-4c36-8477-af6d218433c8","Incorporating Project Complexities in Risk Assessment: Case of an Airport Expansion Construction Project","Ökmen, Ö. (TU Delft Integral Design & Management); Bosch-Rekveldt, M.G.C. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management); Leijten, M. (TU Delft Organisation & Governance); Andringa, Lise","","2022","In today’s construction projects, which are getting more complex as a consequence of especially technical, organizational, and external aspects, complexities are considered a major source of risks. Moreover, risks may turn to complexity-creating elements and propagate additional risks through a bidirectional interaction. Complex construction projects, typically large-scale dynamic endeavors, require the realization of a high number of interdependent tasks through the consumption of various resources such as time, money, labor, and materials. In such projects, while complexities are usually assumed to be given or embedded, due to the subjective and dynamic characteristics of complexities, a tailored approach is required in order to manage them holistically without ignoring their interactions with risks. In this context, the aim of this study is to propose a practical approach that could be utilized to incorporate project complexities in the risk assessment of complex construction projects. The proposed approach entails the integrated usage of risk registers, risk breakdown structures, and complexity-incorporated risk-influence diagrams along with the utilization of a previously developed complexity assessment framework. The underlying basic assumption was that the complexities could directly or indirectly trigger risks, while the risks in turn affect the project objectives. The implementation of the approach in the case of an airport expansion construction project showed that linking the risks to project objectives starting from complexities based on this assumption is possible. In this way, it was shown that multidimensional cause-effect relationships between the complexities and risks, among the risks themselves, and the impact of this interaction on project objectives could be detected and diagrammatically evaluated. Furthermore, it was observed that incorporating complexities in the earlier stages of a project would lead to improvement in the assessment of risks. Considering the results of the case study, the proposed approach has the potential to contribute to improved risk management.","","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-03-10","","","Integral Design & Management","","",""
"uuid:f9fd32e8-38e6-4e92-9f26-5079069d289e","http://resolver.tudelft.nl/uuid:f9fd32e8-38e6-4e92-9f26-5079069d289e","Action-Based Embodied Design for Proportions: From the Laboratory to the Classroom","Alberto, Rosa (Universiteit Utrecht); van Helden, G. (TU Delft Space Systems Egineering); Bakker, Arthur (Universiteit Utrecht)","","2022","Embodied learning technologies have shown efficacy in laboratories with ideal supportive conditions, but their effectiveness in classroom with “real-world” constraints is yet understudied. Inspired by the innovation implementation framework, we compare the classroom-situated engagements of two student pairs and their teachers with the action-based embodied design for proportions with earlier laboratory and classroom study findings and conjecture on influential factors. Much of these classroom students’ sensorimotor learning resembled laboratory findings, but they had more opportunities to be overtly engaged with their hands and self-directed in including artifacts, likely influenced by (unintended) technological changes and setting-specific environmental affordances. Their teachers’ engagements resembled laboratory findings to some extent, but showed less perceptiveness to students’ qualitative multimodal expressions and more directedness in introducing new quantitative forms of
engagements, likely influenced by setting-specific fragmented access and novelty of the embodied pedagogy. We discuss the importance of focusing on teachers and conducting semi-natural efficacy research.","Embodied cognition; Mathematics education; Classroom implementation; Proportions; Educational Technology","en","journal article","","","","","","","","","","","Space Systems Egineering","","",""
"uuid:27c401cd-f595-4900-8f34-e370232f7b49","http://resolver.tudelft.nl/uuid:27c401cd-f595-4900-8f34-e370232f7b49","Arnold Verruijt (1940-2022)","Bakker, M. (TU Delft Water Resources); Haitjema, Henk M. (Haitjema Consulting Inc.); Strack, Otto D.L. (University of Minnesota Twin Cities)","","2022","","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:27f83ef5-44f2-49fe-9f21-db4cd9ef9bc1","http://resolver.tudelft.nl/uuid:27f83ef5-44f2-49fe-9f21-db4cd9ef9bc1","Collaboration and Data Sharing in Inter-Organizational Infrastructure Construction Projects","Rikhtegarnezami, M. (TU Delft Integral Design & Management); de Bruijne, M.L.C. (TU Delft Organisation & Governance); Hertogh, M.J.C.M. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2022","A close collaboration between infrastructure owners is crucial to address challenges in the design and execution of next-generation infrastructure projects for sustainable development. Managing and sharing data among parties involved in infrastructure projects, particularly the data required at the early stages of a project to design and develop an interconnected infrastructure project, appear to play a critical role in inter-organizational collaboration (IOC), but are often overlooked. In the present work, the status of collaboration and data sharing between infrastructure owners in inter-organizational infrastructure projects is studied to enhance our understanding of the relationship between collaboration and data sharing in horizontal IOCs. Explorative semi-structured interviews with practitioners were conducted at organizational and project levels in the infrastructure sectors in The Netherlands. The outcomes revealed that the theoretical benefits of IOC are not realized in practice and that managing and sharing data between infrastructure owners in inter-organizational projects (IOP) face many challenges. The findings suggest that collaboration and data sharing are interrelated in horizontal IOCs and are deemed crucial for the execution of IOPs. The findings of the present study demonstrate the importance of the bilateral relationship between effective collaboration and data sharing and provide an enhanced insight into horizontal forms of IOC and practices of next-generation infrastructure development.","interconnected infrastructure; inter-organizational projects; horizontal collaboration; data sharing; inter-organizational project management; inter-organizational collaboration","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:afc2d39f-fd74-4f66-bd3c-0b514d7791e0","http://resolver.tudelft.nl/uuid:afc2d39f-fd74-4f66-bd3c-0b514d7791e0","An ex-ante analysis of transport impacts of a distance-based heavy goods vehicle charge in the Netherlands","de Bok, M.A. (TU Delft Transport and Planning; Significance); de Jong, Gerard (Student TU Delft; ITS Leeds); Wesseling, Bart (Significance); Meurs, Henk (MuConsult); Van Bekkum, Peter (MuConsult); Mijjer, Peter (4cast); Bakker, Dick (4cast); Veger, Teun (Rijkswaterstaat)","","2022","In 2017, the newly installed Dutch government announced in its coalition agreement to introduce a distancebased heavy goods vehicle charge, similar to the charges levied in other European countries. To study the possible transport impacts, we applied available models and methods in preparation for the introduction of this truck charge in the Netherlands in 2023, in order to present decision information to the government on different aspects of the charge. In this paper we present the analysis of different implementation scenarios for a distancebased truck charge. Different behavioural responses can be expected in terms of freight transport demand, mode choice, logistic efficiency, and route choice. Many studies however lack sufficient detail to properly describe the
impact of road charges for HGV on OD flows and freight traffic. In our contribution we explore the bandwidth of impacts of different pricing schemes, using strategic transport models for freight demand and traffic assignment,
with detailed modal split and route choice models, ensuring a proper representation of generalsed transport costs. We explain how we use available transport models in an overarching analytical framework to make a
comprehensive impact assessment of the different responses, and to decompose the impacts on the different responses. Final impacts are quantified in terms of freight demand (spatial pattern of transport flows), modal split and traffic flows (route choice, and congestion).
Depending on the pricing scenario the tonne kilometres decrease by 0.4%–4.8% on average. The modal shift impacts are stronger on longer transport distances: this is explained both by the larger impact of a distance-based charge on these routes, and by higher substitution possibilities to barge or rail. The results indicate that the overall impacts of the introduction of the different charging alternatives are moderate. However, the network impacts at local level can be substantial due to the impact of re-routing of truck trips to avoid charge.","And congestion (R41); Road pricing (R48); Supply; Transportation planning (R42); Transportation: demand","en","journal article","","","","","","","","","","","Transport and Planning","","",""
"uuid:7efb3e60-112f-43d8-9b41-86b2c43891a2","http://resolver.tudelft.nl/uuid:7efb3e60-112f-43d8-9b41-86b2c43891a2","Determining the decomposition voltage of Cu(In1-xGax)Se2","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices; DIANA FEA; Institut des Matériaux Jean Rouxel); Matas, Joaquin Coll (DIANA FEA); Bosman, J.G. (TU Delft Analysis; DIANA FEA); Barreau, Nicolas (Institut des Matériaux Jean Rouxel); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; TNO Energy Transition); Theelen, M.J. (TU Delft Photovoltaic Materials and Devices; DIANA FEA)","","2022","Partial shading of CIGS modules can lead to permanent damage of the module in the shaded area. This is caused by harmful reverse bias voltages in the shaded area which lead to reverse bias induced defects, also known as wormlike defects. A lot is already known about the origin and propagation of wormlike defects. However, the fundamental question; why is CIGS so sensitive to reverse bias damage? has not yet been answered. In this study we show that CIGS semiconductor material in the presence of an electric field will spontaneously decompose.","CIGS; decomposition; partial shading; reliability; reverse bias","en","conference paper","Institute of Electrical and Electronics Engineers (IEEE)","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-07-01","","","Photovoltaic Materials and Devices","","",""
"uuid:85982685-17cb-4852-bc7c-4bb882f46c6c","http://resolver.tudelft.nl/uuid:85982685-17cb-4852-bc7c-4bb882f46c6c","The strategic value of design for remanufacturing: a case study of professional imaging equipment","Boorsma, Nina (TU Delft Circular Product Design); Peck, David (TU Delft Climate Design and Sustainability); Bakker, Tanya (3penguins); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2022","Remanufacturing offers an approach to extend product lifetime beyond its first use. After restoring products to original quality, they are reintroduced to the market. To make products more suited for this approach, and to increase resource-efficiency, design for remanufacturing can be incorporated for new product development. Academic literature points out opportunities for improved implementation particularly through early-stage design activities. This paper presents an in-depth, single case study into the opportunities and barriers to incorporate design for remanufacturing ine early-stage design. The selected case company is a producer of professional imaging equipment with an internal remanufacturing division. The company has decades of experience in remanufacturing and has introduced a company standard on design for End-of-Life. For data collection, employees from different departments were interviewed and observed. Design management theory was used to combine findings from all perspectives into a company-specific strategy map. This map shows departmental interrelations and dependencies, and exposes the opportunities for creating new value through design. At the case company, remanufacturing was found to be separate from, and secondary to, the development of newly manufactured products. If the strategy of a company is not attuned to developing products that serve multiple use-cycles, its execution will remain sub-optimal and remanufacturing will be a value-retention strategy in isolation. These findings may be valid for other companies that have remanufacturing operations, which are separate, as well.","Circular economy; Circular product design; Design strategy; Printers; Soft barriers; Sustainable design","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:7c82e67f-b363-4e46-8d1f-e8d5c1f468f7","http://resolver.tudelft.nl/uuid:7c82e67f-b363-4e46-8d1f-e8d5c1f468f7","An overview of induced seismicity in the Netherlands","Muntendam-Bos, A.G. (TU Delft Applied Geology); Hoedeman, Gerco (Staatstoezicht op de Mijnen); Polychronopoulou, Katerina (Seismotech S.A.); Draganov, D.S. (TU Delft Applied Geophysics and Petrophysics); Weemstra, C. (TU Delft Applied Geophysics and Petrophysics; Royal Netherlands Meteorological Institute (KNMI)); van der Zee, Wouter (Staatstoezicht op de Mijnen); Bakker, R.R. (TU Delft Reservoir Engineering; Staatstoezicht op de Mijnen); Roest, J.C. (Staatstoezicht op de Mijnen)","","2022","We present an overview of induced seismicity due to subsurface engineering in the Netherlands. Our overview includes events induced by gas extraction, underground gas storage, geothermal heat extraction, salt solution mining and post-mining water ingress. Compared to natural seismicity, induced events are usually small (magnitudes ≤ 4.0). However, due to the soft topsoils in combination with shallow hypocentres, in the Netherlands events exceeding magnitude 1.5–2.0 may be felt by the public. These events can potentially damage houses and infrastructure, and undermine public acceptance. Felt events were induced by gas production in the north of the Netherlands and by post-mining water ingress in the south-east. Notorious examples are the earthquakes induced by gas production from the large Groningen gas field with magnitudes up to 3.6. Here, extensive non-structural damage incurred and public support was revoked. As a consequence, production will be terminated in 2022 leaving approximately 800 billion cubic metres of gas unexploited. The magnitudes of the events observed at underground gas storage, geothermal heat production and salt solution mining projects have so far been very limited (magnitudes ≤ 1.7). However, in the future larger events cannot be excluded. Project- or industry-specific risk governance protocols, extensive gathering of subsurface data and adequate seismic monitoring are therefore essential to allow sustainable use of the Dutch subsurface now and over the decades to come.","fault reactivation; Induced seismicity; Netherlands; seismic hazard; subsurface engineering","en","journal article","","","","","","","","","","","Applied Geology","","",""
"uuid:b508f12b-2c18-47ff-a813-fc135c6694b6","http://resolver.tudelft.nl/uuid:b508f12b-2c18-47ff-a813-fc135c6694b6","The FATE System Iterated: Fair, Transparent and Explainable Decision Making in a Juridical Case","de Boer, Maaike H.T. (TNO); Vethman, Steven (TNO); Bakker, R.M.B. (TNO); Adhikari, Ajaya (TNO); Marcus, Michiel (TNO); de Greeff, Joachim (TNO); van der Waa, J.S. (TU Delft Interactive Intelligence; TNO); van Zoelen, E.M. (TU Delft Interactive Intelligence; TNO); Kamphorst, Bart (TNO)","","2022","The goal of the FATE system is decision support with use of state-of-the-art human-AI co-learning, explainable AI and fair, secure and privacy-preserving usage of data. This AI-based support system is a general system, in which the modules can be tuned to specific use cases. The FATE system is designed to address different user roles, such as a researcher, domain expert/consultant and subject/patient, each with their own requirements. Having examined a Diabetes Type 2 use case before, in this paper we slightly iterate the FATE system and focus on a juridical use case. For a given new juridical case the relevant older court cases are suggested by the system. The relevant older cases can be explained using the eXplainable AI (XAI) module, and the system can be improved based on feedback about the relevant cases using the Co-learning module through interaction with a user. In the Bias module, the use of the system is investigated for potential bias by inspecting the properties of suggested cases. Secure Learning offers privacy-by-design alternatives for functionality found in the aforementioned modules. These results show how the generic FATE system can be implemented in a number of real-world use cases. In future work we plan to explore more use cases within this system.","Bias; Co-Learning; Explainable AI; FAIR AI; Hybrid AI; Knowledge Engineering; Secure Learning","en","journal article","","","","","","","","","","","Interactive Intelligence","","",""
"uuid:635bc541-1597-4db4-a503-823a67b9a1e9","http://resolver.tudelft.nl/uuid:635bc541-1597-4db4-a503-823a67b9a1e9","Estimating tropical cyclone-induced wind, waves, and surge: A general methodology based on representative tracks","Bakker, Tije M. (Student TU Delft; Deltares); Antolínez, José A. Á. (TU Delft Coastal Engineering); Leijnse, T.W.B. (Deltares); Pearson, S.G. (TU Delft Environmental Fluid Mechanics; Deltares); Giardino, Alessio (Asian Development Bank)","","2022","Tropical Cyclones (TCs) are singular storms causing intense wind, large waves, extreme water levels, and heavy rainfall. TCs prove every year to be one of the most destructive natural phenomena worldwide. The quantitative assessment of the hazards resulting from TCs (i.e., flooding and extreme winds) is challenging since satellite data are only available for recent decades, whereas older historical observations are incomplete and less accurate. In addition, long-term prediction through numerical weather forecasting is still limited. This often results in large uncertainties in the definition of TC hazards associated with events with longer return periods or in areas infrequently impacted by TCs. Even when this information is available, for example through statistical sampling of synthetic TC tracks, the numerical modelling of the associated hazards for all the different TC conditions can lead to computational costs which are often infeasible. Several methodologies that overcome the issues of accuracy and computational efficiency currently exist, but these are not generically applicable, and they tend to focus on specific areas only, for example where TCs typically make landfall. The main contribution of this paper is a novel methodology for the estimation and analysis of TC hydro-meteorological conditions and induced hazards. The method is generically applicable and maximizes accuracy while accounting for computational efficiency. Our approach identifies a smaller but representative set of TC tracks (RTCs) that preserves the information about extremes and the frequency of events of the larger population. The method is successfully applied and validated in a case study in the Bay of Bengal, using a set of synthetic TC tracks representing 1000 years of TC climate. For the best-performing configuration, the required number of scenarios and associated computational costs were reduced by 90% while maintaining accuracy in the simulated offshore storm surges, significant wave height, and windspeeds typically within 10% of the prediction based on the original full set of scenarios. This method is globally applicable and greatly improves the efficiency of TC-related hazard estimation, making it particularly valuable for areas with limited historical data.","Dissimilarity selection; Flood hazard; Hybrid downscaling; Synthetic tropical cyclones; TCWiSE; Tropical cyclones","en","journal article","","","","","","","","","","","Coastal Engineering","","",""
"uuid:1eac7635-a38a-44b9-a1ea-9b1d7c23565a","http://resolver.tudelft.nl/uuid:1eac7635-a38a-44b9-a1ea-9b1d7c23565a","A new method to detect changes in displacement rates of slow-moving landslides using InSAR time series","Urgilez Vinueza, A.R. (TU Delft Water Resources); Handwerger, Alexander L. (University of California; California Institute of Technology); Bakker, M. (TU Delft Water Resources); Bogaard, T.A. (TU Delft Water Resources)","","2022","Slow-moving landslides move downslope at velocities that range from mm year−1 to m year−1. Such deformations can be measured using satellite-based synthetic aperture radar interferometry (InSAR). We developed a new method to systematically detect and quantify accelerations and decelerations of slowly deforming areas using InSAR displacement time series. The displacement time series are filtered using an outlier detector and subsequently piecewise linear functions are fitted to identify changes in the displacement rate (i.e., accelerations or decelerations). Grouped accelerations and decelerations are inventoried as indicators of potential unstable areas. We tested and refined our new method using a high-quality dataset from the Mud Creek landslide, CA, USA. Our method detects accelerations and decelerations that coincide with those previously detected by manual examination. Second, we tested our method in the region around the Mazar dam and reservoir in Southeast Ecuador, where the time series data were of considerably lower quality. We detected accelerations and decelerations occurring during the entire study period near and upslope of the reservoir. Application of our method results in a wealth of information on the dynamics of the surface displacement of hillslopes and provides an objective way to identify changes in displacement rates. The displacement rates, their spatial variation, and the timing of accelerations and decelerations can be used to study the physical behavior of a slow-moving slope or for regional hazard assessment by linking the timing of changes in displacement rates to landslide causal and triggering factors.","Change detection method; InSAR time series analysis; Landslide acceleration; Landslide deceleration","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:aed0fab3-a0d7-41d1-886e-4cc497b2f15f","http://resolver.tudelft.nl/uuid:aed0fab3-a0d7-41d1-886e-4cc497b2f15f","Evidence of regional sea-level rise acceleration for the North Sea","Steffelbauer, D.B. (TU Delft Water Resources; Kompetenzzentrum Wasser Berlin); Riva, R.E.M. (TU Delft Physical and Space Geodesy); Timmermans, Jos (TU Delft Policy Analysis); Kwakkel, J.H. (TU Delft Policy Analysis); Bakker, M. (TU Delft Water Resources)","","2022","Global mean sea-level rise (SLR) has accelerated since 1900 from less than 2 mm yr-1 during most of the century to more than 3 mm yr-1 since 1993. Decision-makers in coastal countries, however, require information on SLR at the regional scale, where detection of an acceleration in SLR is difficult, because the long-term sea-level signal is obscured by large inter-annual variations with multi-year trends that are easily one order of magnitude larger than global mean values. Here, we developed a time series approach to determine whether regional SLR is accelerating based on tide gauge data. We applied the approach to eight 100-year records in the southern North Sea and detected, for the first time, a common breakpoint in the early 1990s. The mean SLR rate at the eight stations increases from 1.7 ± 0.3 mm yr-1 before the breakpoint to 2.7 ± 0.4 mm yr-1 after the breakpoint (95% confidence interval), which is unprecedented in the regional instrumental record. These findings are robust provided that the record starts before 1970 and ends after 2015. Our method may be applied to any coastal region with tidal records spanning at least 40 years, which means that vulnerable coastal communities still have time to accumulate the required time series as a basis for adaptation decisions in the second half of this century.","breakpoint detection; regional acceleration; sea-level rise; timely adaptation; OA-Fund TU Delft","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:46dc9fe4-6192-49fb-b094-c835067bc7e4","http://resolver.tudelft.nl/uuid:46dc9fe4-6192-49fb-b094-c835067bc7e4","Trust in Clinical AI: Expanding the Unit of Analysis","Browne, J.T. (TU Delft Methodologie en Organisatie van Design; Philips Research); Bakker, Saskia (Philips Research); Yu, Bin (Philips Research); Lloyd, P.A. (TU Delft Methodologie en Organisatie van Design); Ben Allouch, Somaya (Hogeschool van Amsterdam; Universiteit van Amsterdam)","Schlobach, Stefan (editor); Perez-Ortiz, Maria (editor); Tielman, Myrthe (editor)","2022","From diagnosis to patient scheduling, AI is increasingly being considered across different clinical applications. Despite increasingly powerful clinical AI, uptake into actual clinical workflows remains limited. One of the major challenges is developing appropriate trust with clinicians. In this paper, we investigate trust in clinical AI in a wider perspective beyond user interactions with the AI. We offer several points in the clinical AI development, usage, and monitoring process that can have a significant impact on trust. We argue that the calibration of trust in AI should go beyond explainable AI and focus on the entire process of clinical AI deployment. We illustrate our argument with case studies from practitioners implementing clinical AI in practice to show how trust can be affected by different stages in the deployment cycle.","Artificial Intelligence; Clinical AI; Trust; Trust Calibration","en","conference paper","IOS Press","","","","","","","","","","Methodologie en Organisatie van Design","","",""
"uuid:b791a84c-53af-4d61-8137-5fc5afcc83df","http://resolver.tudelft.nl/uuid:b791a84c-53af-4d61-8137-5fc5afcc83df","How User Manuals Support the Diagnosis of Common Faults in Household Appliances: An Analysis of 150 manuals","Pozo Arcos, B. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2022","Product repairs are at the core of sustainable consumption and user manuals can play a relevant role in facilitating them. They are the accredited source of product information for end users and are therefore sought as an important means for the diagnosis and subsequent repair of household appliances. However, despite increasing societal demand for repairable products, few studies have been conducted on the extent to which manuals contribute to
the fault diagnosis and subsequent repair process. In this study, we analysed current guidance provided by manuals for the diagnosis process, answering the research question: ‘To what extent do user manuals provide sufficient information to diagnose the most frequent faults in household appliances?’ We examined the diagnosis instructions provided in the user manuals of four different household appliances using data on the appliances’ most frequently failing components, and a framework that considers three steps towards a suc-
cessful diagnosis: fault detection, fault location, and fault isolation. In total, we analysed 150 user manuals of 48 brands available on the European market. We show that manuals do not instruct the diagnosis of frequently failing components. They mainly refer to causes of failure and directly recommend corrective actions after fault detection. Thus, they rarely include a three-step fault diagnosis process to identify and isolate a faulty component.
Based on these results, we have extended the framework for the process of fault diagnosis to include a step from cause identification to corrective action. Both routes, the component- oriented and the cause-oriented route in fault diagnosis, should be considered during the design of products for easy fault diagnosis, and should be included in future regulations that address product reparability","","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:1223bb4f-8a10-4be1-97a2-2652ec5b372a","http://resolver.tudelft.nl/uuid:1223bb4f-8a10-4be1-97a2-2652ec5b372a","Development of the Circular Product Readiness Method in Circular Design","Boorsma, N.E. (TU Delft Circular Product Design); Polat, E. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Peck, David (TU Delft Climate Design and Sustainability); Balkenende, R. (TU Delft Circular Product Design)","","2022","Design indicators can be used by companies to track circular design implementation, which can yield insights into their performance and opportunities for improvement. Yet, existing indicator methods either lack depth with regard to circular design, are incomplete, or do not use design semantics. This study explores product-level circularity indicators, with the aim of developing a comprehensive circularity indicator method specifically aimed at designers. The method development process follows a three step Design Science Research approach. It comprises a literature review and knowledge coproduction sessions with circular design experts on topics such as durability, repair, remanufacturing, and recycling. Furthermore, it includes company evaluations with two multinational corporations operating in the white goods and automotive industries. The study delivers the first indicator method for assessing circular product design on a broad range of aspects, including levels of readiness, company strengths, and opportunities for improvement. The method uses product design semantics to evaluate design aspects, takes a comprehensive view of the full life cycle, and has been specifically developed for industry use.","sustainable manufacturing; sustainable design; design roadmap","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:e4cdedfc-e692-47af-a539-642e125f6889","http://resolver.tudelft.nl/uuid:e4cdedfc-e692-47af-a539-642e125f6889","Circular Composites by Design: Testing a Design Method in Industry","Joustra, J.J. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Bessai, R. (TU Delft Design for Sustainability); Balkenende, R. (TU Delft Circular Product Design)","","2022","The design of composite products for a circular economy is challenging. Materials such as glass-fibre-reinforced plastics have long product lifetimes but are hard to recycle. For the effective reuse and recycling of products, parts, and materials, recovery strategies must be selected and implemented in the product design stage. This extends the scope and complexity of the design process and requires additional skills from the designers. We developed a novel circular composites design method for products containing composite materials to support designers and improve product circularity. This method, which is the first of its kind to address the circular design of composite products, helps designers explore recovery pathways and generate design solutions. In this study, we evaluated the method’s effectiveness, accessibility, and usability in design practice. We tested the method with five design case studies in the construction, furniture, and automotive industries. The method was used to generate, evaluate, communicate, and detail product designs. We found that two of the five cases used the method to develop circular product concepts. In the other three cases, recycling rather than product-level recovery strategies was the result, with a focus on improving the material formulations instead of the overall product design. Although the designers considered the method accessible and usable, its effectiveness was restricted by the existing business, logistics, reprocessing technology, and policy contexts. These factors are intertwined and partly dictate the boundary conditions of the design, which means that to successfully implement the proposed method, the transition to a circular economy requires a holistic approach to adjust the design process, organisations, and value chains.","circular economy; product design; composite materials; design methodology","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:fa95e209-915e-4dce-914a-adfaeb7d121a","http://resolver.tudelft.nl/uuid:fa95e209-915e-4dce-914a-adfaeb7d121a","Bio-based plastics in durable applications: The future of sustainable product design? A design review","Bos, P. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design); Sprecher, B. (TU Delft Design for Sustainability)","Lockton, Dan (editor); Lenzi, Sara (editor); Hekkert, Paul (editor); Oak, Arlene (editor); Sádaba, Juan (editor); Lloyd, Peter (editor)","2022","This design review evaluates the use of bio-based plastics in durable consumer products. The main question is: how does the use of bio-based plastics influence the product’s design, functionality, marketing & communication, and sustainability? Although higher material prices would lead one to expect that higher value applications would be targeted, research shows bio-based plastics are mainly used in short-lived applications like packaging. This study investigates their use in durable consumer products through a design review. The results indicate that bio-based plastic usage is still in its early days in durable products. Bio-based plastics appear to be utilized as straightforward replacement of fossil-based plastic. Designers are not yet using the unique properties of bio-based plastics in the design of their products. Companies mainly exploit the green image of bio-based plastics in their marketing & communication. Their focus is on the renewable feedstock and not on sourcing, or on recovery at end-of-life.","Bio-based plastic; Product design; Design review; Circular Economy (CE)","en","conference paper","","","","","","","","","","","Circular Product Design","","",""
"uuid:f6b97d2f-0c48-4748-b5d5-2ac49578729d","http://resolver.tudelft.nl/uuid:f6b97d2f-0c48-4748-b5d5-2ac49578729d","Improving the performance of civil engineering projects through the integrated design process","Keusters, A.C.A.M. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management); Houwing, E.J. (TU Delft Integral Design & Management)","","2022","Purpose: Civil engineering projects around the world have been underperforming for a long time. While the complexity of these projects will continue to increase, there is an urgent need to perform better. Although the integrated design process is critical for project success, the literature lacks studies describing the link to project performance. Therefore, this study aims to investigate the dominant variables that affect the integrated design process and consequently project performance. Design/methodology/approach: A multiple case study was conducted to determine the dominant variables that affect the integrated design process and project performance. The research included four projects. Semi-structured interviews were the main source of data. Findings: The cases indicated that the extent to which an integrated approach is achieved in the design process is essential for project performance. This applies to the integration of stakeholders’ interests as well as the integration of disciplines. Above all, it was concluded that the project team participants’ competencies for integration are a dominant factor for project performance, as the integrated design process has changed from a technical challenge to an integrative one. Originality/value: This study provides insights into the dominant variable of the integrated design process that affects project performance, which is underexposed in the literature. The study results reveal the importance of competencies related to integration and adoption of the design problem context, which are not yet included in civil engineering design methods. In this respect, empathy is introduced as a new and critical competence for the civil engineering industry, which needs further research.","Complexity; Design; Human factors engineering; Integrated design; Project performance","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2022-07-27","","","Integral Design & Management","","",""
"uuid:c8c6174d-259a-4913-941c-24b17c75f305","http://resolver.tudelft.nl/uuid:c8c6174d-259a-4913-941c-24b17c75f305","Interactive animation on Directional derivatives & Level curves","Ranjha, Sayra (Student TU Delft); Hoveling, V.T. (TU Delft Support Delft Institute of Applied Mathematics); van Gelderen, B.E. (TU Delft Support Delft Institute of Applied Mathematics); van de Bult, F.J. (TU Delft Analysis); den Ouden-van der Horst, D. (TU Delft Numerical Analysis); Smet, C.O. (TU Delft Statistics); Roelvink, M.A.T. (TU Delft Support Delft Institute of Applied Mathematics); Bakker, I.P. (TU Delft Support Delft Institute of Applied Mathematics)","Spencer, Stephen N. (editor)","2021","We present our short series of interactive animations on directional derivatives and level curves. This visualisation was developed for students of first-year mathematics courses at the Delft University of Technology. The interactive animation is an animated video that can be interacted with while it is paused or playing. The user can change, for example, the function that is plotted, drag points of interest or change the angle of the camera to explore the scene.","","en","conference paper","Association for Computing Machinery (ACM)","","","","","","","","","","Support Delft Institute of Applied Mathematics","","",""
"uuid:24b463d7-5f25-4c87-b7fc-1082f53cefff","http://resolver.tudelft.nl/uuid:24b463d7-5f25-4c87-b7fc-1082f53cefff","Interaction Effects Between Aquifer Thermal Energy Storage Systems","Duijff, R. (TU Delft Water Resources; DWA, Gouda); Bloemendal, Martin (TU Delft Water Resources; KWR Water Research Institute); Bakker, M. (TU Delft Water Resources)","","2021","Aquifer thermal energy storage (ATES) is an energy efficient technique to provide heating and cooling to buildings by storage of warm and cold water in aquifers. In regions with large demand for ATES, ATES adoption has lead to congestion problems in aquifers. The recovery of thermal energy stored in aquifers can be increased by reducing the distance between wells of the same temperature while safeguarding individual system performance. Although this approach is implemented in practice, the understanding of how this affects both the recovery efficiency and the needed pumping energy is lacking. In this research, the effect of well placement on the performance of individual systems is quantified, and guidelines for planning and design are developed. Results show an increase in thermal recovery efficiency of individual systems when the thermal zones of wells of the same temperature are combined, which is explained by reduced surface area of the thermal zone over which losses occur. The highest increase of the thermal recovery efficiency is found for systems with a small storage volume and long well screens. The relative increase of the thermal recovery efficiency is 12% for average-sized systems with a storage volume of 250,000 m3/year, and 25% for small systems (50,000 m3/year). The optimal distance between wells of the same temperature is 0.5 times the thermal radius, following the trade-off between an increase of the thermal recovery efficiency and the increase in pumping energy. The distance between wells of opposite temperature must be larger than three times the thermal radius to avoid negative interaction.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:b6920913-20da-46e4-99a6-276481deca3b","http://resolver.tudelft.nl/uuid:b6920913-20da-46e4-99a6-276481deca3b","A conceptual model to determine the impact of off-site construction on labour productivity","van Dijkhuizen, M.J. (TU Delft Integral Design & Management); Vrijhoef, R. (TU Delft Design & Construction Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","Alarcon, Luis Fernando (editor); Gonzalez, Vicente A. (editor); Murguia, Danny (editor); Brioso, Xavier (editor)","2021","Despite the efforts of governments and firms, the construction industry is trailing other industries in labour productivity. Construction companies are interested in increasing their labour productivity, particularly when demand grows and construction firms cope with labour shortages. Off-site construction has proved to be a favourable policy to increase labour productivity. However, a complete understanding of the factors affecting construction labour productivity is lacking, and it is unclear which factors are influenced by off-site construction. This study developed a conceptual model describing how 15 factors influence the construction process and make a difference in labour productivity between off-site and on-site construction. The conceptual model shows that all 15 factors affect labour productivity in three ways: through direct effects, indirect effects and causal loops. The model is a starting point for further research to determine the impact of off-site construction on labour productivity.","Labour productivity; construction process; off-site construction; modelling","en","conference paper","","","","","","","","","","","Integral Design & Management","","",""
"uuid:880ffebb-f1bc-4118-be7b-33931bf63264","http://resolver.tudelft.nl/uuid:880ffebb-f1bc-4118-be7b-33931bf63264","Part III - Ch 3 Waterway elements","Verheij, H.J. (TU Delft Rivers, Ports, Waterways and Dredging Engineering); van der Hout, A.J. (TU Delft Rivers, Ports, Waterways and Dredging Engineering; Deltares); Koedijk, O.C. (TU Delft Rivers, Ports, Waterways and Dredging Engineering; Rijkswaterstaat); Bakker, F.P. (TU Delft Rivers, Ports, Waterways and Dredging Engineering); van Koningsveld, M. (TU Delft Rivers, Ports, Waterways and Dredging Engineering; Van Oord); de Vriend, H.J. (TU Delft Rivers, Ports, Waterways and Dredging Engineering)","Koningsveld, Mark van (editor); Verheij, H.J. (editor); Taneja, P. (editor); de Vriend, H.J. (editor)","2021","","","en","book chapter","TU Delft OPEN Publishing","","","","","","","","","","Rivers, Ports, Waterways and Dredging Engineering","","",""
"uuid:bc6cfb60-179a-40ac-aeb7-d6e35865c37b","http://resolver.tudelft.nl/uuid:bc6cfb60-179a-40ac-aeb7-d6e35865c37b","Molecular Structure and Surface Accumulation Dynamics of Hyaluronan at the Water-Air Interface","Moll, Carolyn J. (AMOLF); Giubertoni, Giulia (AMOLF); van Buren, L. (TU Delft BN/Gijsje Koenderink Lab; Kavli institute of nanoscience Delft; AMOLF); Versluis, Jan (AMOLF); Koenderink, G.H. (TU Delft BN/Gijsje Koenderink Lab; Kavli institute of nanoscience Delft; AMOLF); Bakker, Huib J. (AMOLF)","","2021","Hyaluronan is a biopolymer that is essential for many biological processes in the human body, like the regulation of tissue lubrication and inflammatory responses. Here, we study the behavior of hyaluronan at aqueous surfaces using heterodyne-detected vibrational sum-frequency generation spectroscopy (HD-VSFG). Low-molecular-weight hyaluronan (∼150 kDa) gradually covers the water-air interface within hours, leading to a negatively charged surface and a reorientation of interfacial water molecules. The rate of surface accumulation strongly increases when the bulk concentration of low-molecular-weight hyaluronan is increased. In contrast, high-molecular-weight hyaluronan (>1 MDa) cannot be detected at the surface, even hours after the addition of the polymer to the aqueous solution. The strong dependence on the polymer molecular weight can be explained by entanglements of the hyaluronan polymers. We also find that for low-molecular-weight hyaluronan the migration kinetics of hyaluronan in aqueous media shows an anomalous dependence on the pH of the solution, which can be explained from the interplay of hydrogen bonding and electrostatic interactions of hyaluronan polymers.","","en","journal article","","","","","","","","","","","BN/Gijsje Koenderink Lab","","",""
"uuid:fe290855-8b2b-4860-a8d2-47386f60b11f","http://resolver.tudelft.nl/uuid:fe290855-8b2b-4860-a8d2-47386f60b11f","Evaluation of Expansion of Managerial Flexibilities of Critical Path Method Scheduling Under Uncertainty Through A Risk Simulation Model","Ökmen, Ö. (TU Delft Integral Design & Management); Bosch-Rekveldt, M.G.C. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2021","Scheduling of a construction project using an activity network can be done using the Critical Path Method (CPM). CPM scheduling, since it was first developed in the USA in 1950’s, has been widely applied in various sectors including the construction sector. CPM, however, is incapable of reflecting the influence of uncertainty on schedules and modelling the stochastic character of projects’ real-life conditions. In order to achieve success in complex, uncertain, and dynamic conditions, today’s construction projects do show a need for methods that are more flexible from a managerial point of view. Therefore, this study investigates the expansion of managerial flexibilities of CPM scheduling in case it would be integrated with Monte Carlo Simulation (MCS) through a schedule risk analysis method called the Correlated Schedule Risk Analysis Model (CSRAM). For this purpose, firstly, the subject is discussed conceptually, and next an example application on a project is introduced to illustrate the potential of CSRAM in terms of flexibility. The flexibilities have been investigated at three levels, i.e. activity, path and project level. The results have revealed that it seems possible to expand the managerial flexibilities inherently present in CPM, in case risk analysis capability is incorporated. However, the level of expansion of managerial flexibilities could change in adverse or favourable direction depending on various factors such as the project phase, project size, project conditions, contract terms, and stakeholder requirements. These factors could be subject of further research. Other scheduling methods used in construction projects such as the Critical Chain Method, Line of Balance and Linear Scheduling Method could be investigated in the same manner to go one step further on the way towards more flexible project management in construction from the scheduling viewpoint.","Critical Path Method; Monte Carlo Simulation; flexible project management; managerial flexibility; schedule risk analysis","en","conference paper","","","","","","","","","","","Integral Design & Management","","",""
"uuid:b53f6f91-bec8-4e5d-806b-440aa73aa8a0","http://resolver.tudelft.nl/uuid:b53f6f91-bec8-4e5d-806b-440aa73aa8a0","Simultaneous optimization of topology and layout of modular stiffeners on shells and plates","Bakker, Coen (Student TU Delft); Zhang, L. (TU Delft Computational Design and Mechanics); Higginson, Kristie (University of Queensland); van Keulen, A. (TU Delft Computational Design and Mechanics)","","2021","Stiffened shells and plates are widely used in engineering. Their performance is highly influenced by the arrangement, or layout, of stiffeners on the base shell or plate and the geometric features, or topology, of these stiffeners. Moreover, modular design is beneficial, since it allows for increased quality control and mass production. In this work, a method is developed that simultaneously optimizes the topology of stiffeners and their layout on a base shell or plate. This is accomplished by introducing a fixed number of modular stiffeners, which are subject to density-based topology optimization and a mapping of these modules to a ground structure. To illustrate potential applications, several stiffened plates and shell examples are presented. All examples demonstrated that the proposed method is able to generate clear topologies for any number of modules and a distinct layout of the stiffeners on the base shell or plate.","Ground structure; Modular design; Stiffener layout; Stiffener topology; Topology optimization","en","journal article","","","","","","","","","","","Computational Design and Mechanics","","",""
"uuid:10b02e8f-eeae-4962-b797-3a8d04600663","http://resolver.tudelft.nl/uuid:10b02e8f-eeae-4962-b797-3a8d04600663","Shifting from blended to online learning: Students’ and teachers’ perspectives","Polat, E. (TU Delft Circular Product Design); van Dam, S.S. (TU Delft Design for Sustainability; TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design)","","2021","The Covid-19 outbreak forced many universities across the world to transition from a traditional or blended format to fully online education. This paper presents a case study on the transition to an online education format for a circular design course. Both quantitative and qualitative data were collected through a survey with 26 students and interviews with six course teachers. The findings revealed that students preferred the on-campus versions over the online course components. They indicated the perceived lack of motivation, lack of sense of community, and a high workload as influencing factors. Teachers indicated the lack of connection with students as a drawback to online education but identified advantages to their teaching and the student’s learning experience. Suggestions for addressing an optimal blended course format are provided.","Case study; Circular economy; Covid-19; Design education; Online learning","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:9d3ffe8d-8522-446c-a3ec-d98d04b70f6b","http://resolver.tudelft.nl/uuid:9d3ffe8d-8522-446c-a3ec-d98d04b70f6b","Rekenen aan levensduurkosten bij lage discontovoeten","van den Boomen, M. (TU Delft Integral Design & Management; Rotterdam University of Applied Sciences; Kenniscentrum Duurzame HavenStad); Bakker, H.L.M. (TU Delft Integral Design & Management); Hertogh, M.J.C.M. (TU Delft Integral Design & Management); Treiture, R. (Rijkswaterstaat)","","2021","Veel publieke organisaties in Nederland rekenen bij contante waarde berekeningen met een maatschappelijke discontovoet. Door de lage discontovoet ontstaat een methodisch probleem bij contante waarde berekening over de gebruikelijke periode van 100 jaar. In dit artikel stellen we drie rekenmethoden voor om tot een evenredige vergelijking te komen bij lage discontovoeten. De aanpak is ook geldig voor het vergelijken van alternatieven met een verschillende levensduur.","","nl","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2022-05-02","","","Integral Design & Management","","",""
"uuid:12399798-3f5b-4908-9ccf-ab366cf41abc","http://resolver.tudelft.nl/uuid:12399798-3f5b-4908-9ccf-ab366cf41abc","Multimodal Dialogue in Small-Group Mathematics Learning","Abdu, Rotem (University of Haifa); van Helden, G. (TU Delft Space Systems Egineering); Alberto, Rosa (Universiteit Utrecht); Bakker, Arthur (Universiteit Utrecht)","","2021","In this paper, we combine dialogic and embodied theories of learning to create a unified analytic lens. Embodied cognition is a theoretical approach operating under the premise that thinking and communication are multimodal activities. Under this premise, dialogue between learners needs to be conceptualized using a multimodal lens. We identify multimodal voices as speech and movement bundles situated within a learning context and describe a phenomenon that we call Multimodal Dialogue – multimodal interaction between different multimodal voices. To demonstrate this phenomenon, we analyze a learning sequence by two third-grade students who participated in a mathematics lesson aimed to foster embodied learning of proportion. Our analysis zooms in on the phenomenon of a multimodal voice as a speech-and-movement bundle situated within a learning context. We further show how multimodal dialogic gaps – differences between multimodal voices within and between modalities – drive communication and eventual changes in voices.","Dialogue; Multimodality; Learning; Small group; Mathematics lesson","en","journal article","","","","","","","","","","","Space Systems Egineering","","",""
"uuid:c1b58929-a39e-4854-a8ab-a6831d89cb16","http://resolver.tudelft.nl/uuid:c1b58929-a39e-4854-a8ab-a6831d89cb16","Pulsed LED line light for large-scale PIV -development and use in wave load measurements","Bakker, W. (TU Delft Hydraulic Structures and Flood Risk; Deltares); Hofland, Bas (TU Delft Hydraulic Structures and Flood Risk); de Almeida Sousa, E. (TU Delft Hydraulic Structures and Flood Risk); Oldenziel, G. (TU Delft Fluid Mechanics; Deltares); Overmars, E.F.J. (TU Delft Fluid Mechanics)","","2021","In this paper the development of a high-power pulsed LED line light and its use to apply particle image velocimetry (PIV) during wave impact measurements are described. An electrical circuit that generates high-current pulses is designed and built, which is used to overdrive a number of commercially available LEDs. The limit for this overdrive-capacity is determined as function of pulse duration for various commercial available LEDs. Two systems of cylindrical convex lenses are designed to act as a collimator and reduce divergence of the LED bundle and the resulting light sheet properties (maximum light intensity and sheet thickness) are investigated. An array of LEDs of 60 cm length (referred to as the LED line light) is designed and manufactured. For the two lens systems, the LED line light provides proper light sheet conditions to illuminate measurement regions in the order of either 0.3 × 0.3 m 2, or 1 × 1 m 2, at a sufficiently constant light sheet thickness of 5 mm. The application of the LED line light is demonstrated by quantifying the instantaneous flow field of a wave impacting on a blunt object in a wave flume. PIV measurements are conducted at an acquisition rate of 25 frame pairs per second, quantifying maximum flow velocities in the order of 1.0 m s -1 at a LED pulse width of 200 µs. The system, consisting of the LED line light, a CMOS camera and open source PIV processing software provides the possibility to perform 2D planar PIV measurements for a fraction of the costs of a commercially available laser based PIV system.","LED line light; LEDPIV; Large-scale PIV; Particle image velocimetry; Wave impact; Wave load","en","journal article","","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:34792ae9-8039-4cf2-959e-b6e0e45bec8a","http://resolver.tudelft.nl/uuid:34792ae9-8039-4cf2-959e-b6e0e45bec8a","The Disassembly Map: A new method to enhance design for product repairability","De Fazio, F.; Bakker, C.A. (TU Delft Circular Product Design); Flipsen, Bas (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2021","Designers and engineers need better tools and methods to create highly repairable products. Design for disassembly and reassembly is an important product related design feature that can enhance repair. In a highly repairable product, the components that fail most often should be easily accessible for repair or replacement. This paper describes the development of a method to visually map the disassembly of a product, showing different routes towards target components. These components can be those with a high potential failure rate (important for repair), embodied environmental impact (important for recycling) and economic value (relevant for component harvesting), depending on the circular strategy under consideration. The ‘Disassembly Map’ method is set up to guide product design and is aligned with the most recent research and standards on product repairability. The ease of disassembly is assessed on Four main design parameters are considered in this method to assess the ease of disassembly of: disassembly sequence/depth, type of tools, fastener reusability/reversibility, and disassembly time. In contrast to most of the related literature found, the Disassembly Map method is not based on the use of an algorithm for the automatic calculation of optimised disassembly sequences. It asks designers and engineers to analyse each disassembly step using standardized visual elements based on the ease of Disassembly Metric (eDiM) and the Maynard Operation Sequence Technique (MOST). Insights gathered from this analysis and the resulting visualisation can be used in an iterative product development process. The method was developed by analysing seven vacuum cleaners. Its effectiveness was then tested by redesigning one of them, enhancing its repairability.","Design method; Disassembly map; Product design; Repair; Repairability; Vacuum cleaner","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:d1675f51-75a2-4a8c-bd0c-0bed58018c94","http://resolver.tudelft.nl/uuid:d1675f51-75a2-4a8c-bd0c-0bed58018c94","Collaborate to learn and learn to collaborate: a case of exploitative learning in the inter-organizational project","Liu, Y. (TU Delft Integral Design & Management); Amini-Abyaneh, Arash (Vrije Universiteit Amsterdam); Hertogh, M.J.C.M. (TU Delft Integral Design & Management); Houwing, E.J. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2021","Purpose: Management of inter-organizational projects focuses on the collective benefits of a group of organizations on a shared activity for a limited period and the coordination among them. However, how learning is facilitated in the inter-organizational project remains under-developed in the literature. Design/methodology/approach: This research analyses the exploitative learning process in the longest tunnel project on land in the Netherlands realized in a densely populated area. Data were collected through archived documents, in-depth interviews, site visits in the ethnographic research to analyze the actors, the daily practices and social situations in projects. Findings: The empirical findings indicate that exploitative learning is promoted positively between the owner and the contractor and internally within the contractor. The most significant change that the exploitative learning process has led to is the change in mindset toward the collaboration. Project culture is considered to be shaped by exploitative learning in the inter-organizational project. However, there is a gap between the transfer of knowledge from the inter-organizational project to the parent organization. Originality/value: The findings have implications for understanding learning in the inter-organizational project setting.","Construction; Innovation; Knowledge management","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:b7f7a987-1909-413d-aaa8-3f86b5f88de2","http://resolver.tudelft.nl/uuid:b7f7a987-1909-413d-aaa8-3f86b5f88de2","The Impact of Co-Creation on the Design of Circular Product-Service Systems: Learnings from a Case Study with Washing Machines","van Dam, S.S. (TU Delft Circular Product Design); Sleeswijk Visser, F. (TU Delft Design Conceptualization and Communication); Bakker, C.A. (TU Delft Circular Product Design)","","2021","Designers play an important role in service transformation and the development of product-service systems by applying co-creation methods. This paper presents a case of how we applied co-creation in practice and the impact this has had on developing a circular product-service system. It details the method used in the co-creation process and highlights five benefits, such as the ability to develop value-adding services for repairs and supporting each of them with user citations. Furthermore, we interviewed the project team a year into product development to assess the uptake by the company and the impact co-creation had on their design process. Based on these findings, we present a conceptual model that identifies the tangible impacts of co-creation and visualizes at what stages and levels co-creation can impact both the development of product-service systems and a company’s shift along the servitization continuum.","access models; circular product design; co-creation; impact; product-service systems; washing machines","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:572f3c23-3663-43c6-b520-0a1ceb5cb7c9","http://resolver.tudelft.nl/uuid:572f3c23-3663-43c6-b520-0a1ceb5cb7c9","Crossroad decisions in deep endometriosis treatment options: a qualitative study among patients","Metzemaekers, Jeroen (Leiden University Medical Center); Slotboom, Suzanne (University of Applied Sciences Leiden); Sampat, Jonathan (Maxima Medical Center, Veldhoven); Vermolen, Polo (Leiden University Medical Center); Smeets, Mathilde J.G.H. (Haaglanden Medical Center); Elske van den Akker-van Marle, M. (Leiden University Medical Center); Maas, Jacques (Maxima Medical Center, Veldhoven); Bakker, Esther C. (Open University of the Netherlands); Nijkamp, Marjan (Open University of the Netherlands); Both, S. (Leiden University Medical Center); Jansen, F.W. (TU Delft Medical Instruments & Bio-Inspired Technology; Leiden University Medical Center)","","2021","Objective: To study the experiences, considerations, and motivations of patients with endometriosis in the decision-making process for deep endometriosis (DE) treatment options. Design: Qualitative study using semi-structured in-depth focus group methodology. Setting: University medical center. Patient(s): A total of 19 Dutch women diagnosed with DE between 27 and 47 years of age. Intervention(s): Not applicable. Main Outcome Measure(s): Focus group topics were disease impact and motives for treatment, expectations of the treatment process, and important factors in the decision process. Result(s): Women reported that pain, fertility, and strong fear of complications are important decisive factors in the treatment process. The goal of conceiving a child is considered important, however, sometimes doctors emphasize this topic too much. It emerged that complication counseling is frequently about surgical complications, whereas side effects of hormonal treatments are neglected. Shared decision making and information about treatment options, complications, and side effects are not always optimal, making it difficult to make a well-considered choice. Despite negative experiences encountered after surgery, the positive effect of surgery ensures that most women do not regret their choice. Conclusion(s): In the treatment decision process for patients with DE, pain is almost always the most important decisive factor. The wish to conceive and strong fear of complications can change this choice. Doctors should understand the importance of fertility for the majority of women, but, also, if this is not considered paramount, respect that view. To improve shared decision making, exploration of treatment goals, training of healthcare providers, and better patient information provision are desirable.","Decision making; endometriosis; focus groups; qualitative research","en","journal article","","","","","","","","","","","Medical Instruments & Bio-Inspired Technology","","",""
"uuid:92d7a5e0-6bf0-40b4-8d07-f1c15b3c37e9","http://resolver.tudelft.nl/uuid:92d7a5e0-6bf0-40b4-8d07-f1c15b3c37e9","GIS as a heuristic tool to interpret ancient historiography: A case study to reconstruct what could plausibly have happened according to the accounts in New Testament texts","van Altena, V.P. (TU Delft Urban Data Science; Vrije Universiteit Amsterdam); Krans, Jan (Protestantse Theologische Universiteit); Bakker, Henk (Vrije Universiteit Amsterdam); Stoter, J.E. (TU Delft Urban Data Science)","","2021","This article examines how GIS can be used as a heuristic tool to reconstruct spatial–temporal events from narratives in order to examine whether a scenario is conceivable within the narrative world. The narrative about Paul's escape from Berea (Acts 17:14–15) is used as a case study. Several interpretive issues related to spatial and temporal questions surround these texts. In the case study, three methods are applied: (a) least-cost path analysis on elevation data to construct journeys and travel times for Roman roads; (b) network analysis to find seafaring routes valid for ancient times; and (c) the integration of spatial and temporal data in a space-time cube. Our main finding is that the method yields insights into the spatial–temporal dynamics of the narrative. This helps a modern reader to better understand the narrative conceivability of a story in the mind of a first-century reader.","","en","journal article","","","","","","","","","","","Urban Data Science","","",""
"uuid:e3dd7f79-044a-4c39-ab91-d36254b9afab","http://resolver.tudelft.nl/uuid:e3dd7f79-044a-4c39-ab91-d36254b9afab","A most painful knee does not induce interlimb differences in knee and hip moments during gait in patients with knee osteoarthritis","Bakker, Nienke F. (Vrije Universiteit Amsterdam); Schrijvers, Jim C. (Vrije Universiteit Amsterdam); van den Noort, Josien C. (Vrije Universiteit Amsterdam; Universiteit van Amsterdam); Hall, Michelle (University of Melbourne); van der Krogt, Marjolein M. (Vrije Universiteit Amsterdam); Harlaar, J. (TU Delft Biomechatronics & Human-Machine Control; Vrije Universiteit Amsterdam; Erasmus MC); van der Esch, Martin (Hogeschool van Amsterdam; Amsterdam Rehabilitation Research Center Reade)","","2021","Background: Patients with knee osteoarthritis can adapt their gait to unload the most painful knee joint in order to try to reduce pain and improve physical function. However, these gait adaptations can cause higher loads on the contralateral joints. The aim of the study was to investigate the interlimb differences in knee and hip frontal plane moments during gait in patients with knee osteoarthritis and in healthy controls. Methods: Forty patients with knee osteoarthritis and 19 healthy matched controls were measured during comfortable treadmill walking. Frontal plane joint moments were obtained of both hip and knee joints. Differences in interlimb moments within each group were assessed using statistical parametric mapping and discrete gait parameters. Findings: No interlimb differences were observed in patients with knee osteoarthritis and control subjects at group level. Furthermore, the patients presented similar interlimb variability as the controls. In a small subgroup (n = 12) of patients, the moments in the most painful knee were lower than in the contralateral knee, while the other patients (n = 28) showed higher moments in the most painful knee compared to the contralateral knee. However, no interlimb differences in the hip moments were observed within the subgroups. Interpretation: Patients with knee osteoarthritis do not have interlimb differences in knee and hip joint moments. Patients and healthy subjects demonstrate a similar interlimb variability in the moments of the lower extremities. In this context, differences in knee pain in patients with knee osteoarthritis did not induce any interlimb differences in the frontal plane knee and hip moments.","Biomechanics; Gait analysis; Hip joint load; Interlimb differences; Knee joint load; Knee osteoarthritis","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2022-02-20","","","Biomechatronics & Human-Machine Control","","",""
"uuid:a8a3f6cc-794d-4907-b44b-5c09e1b5f9d9","http://resolver.tudelft.nl/uuid:a8a3f6cc-794d-4907-b44b-5c09e1b5f9d9","Simultaneous Quantification of the Concentration and Carbon Isotopologue Distribution of Polar Metabolites in a Single Analysis by Gas Chromatography and Mass Spectrometry","Evers, Bernard (University Medical Center Groningen); Gerding, Albert (University Medical Center Groningen); Boer, Theo (University Medical Center Groningen); Heiner-Fokkema, M. Rebecca (University Medical Center Groningen); Jalving, Mathilde (University Medical Center Groningen); Wahl, S.A. (TU Delft BT/Industriele Microbiologie); Reijngoud, Dirk Jan (University Medical Center Groningen); Bakker, Barbara M. (University Medical Center Groningen)","","2021","13C-isotope tracing is a frequently employed approach to study metabolic pathway activity. When combined with the subsequent quantification of absolute metabolite concentrations, this enables detailed characterization of the metabolome in biological specimens and facilitates computational time-resolved flux quantification. Classically, a 13C-isotopically labeled sample is required to quantify 13C-isotope enrichments and a second unlabeled sample for the quantification of metabolite concentrations. The rationale for a second unlabeled sample is that the current methods for metabolite quantification rely mostly on isotope dilution mass spectrometry (IDMS) and thus isotopically labeled internal standards are added to the unlabeled sample. This excludes the absolute quantification of metabolite concentrations in 13C-isotopically labeled samples. To address this issue, we have developed and validated a new strategy using an unlabeled internal standard to simultaneously quantify metabolite concentrations and 13C-isotope enrichments in a single 13C-labeled sample based on gas chromatography-mass spectrometry (GC/MS). The method was optimized for amino acids and citric acid cycle intermediates and was shown to have high analytical precision and accuracy. Metabolite concentrations could be quantified in small tissue samples (≥20 mg). Also, we applied the method on 13C-isotopically labeled mammalian cells treated with and without a metabolic inhibitor. We proved that we can quantify absolute metabolite concentrations and 13C-isotope enrichments in a single 13C-isotopically labeled sample.","","en","journal article","","","","","","","","","","","BT/Industriele Microbiologie","","",""
"uuid:54704650-300b-4f1e-bb39-d32cc9f56960","http://resolver.tudelft.nl/uuid:54704650-300b-4f1e-bb39-d32cc9f56960","Estimation of groundwater recharge from groundwater levels using nonlinear transfer function noise models and comparison to lysimeter data","Collenteur, Raoul A. (Karl-Franzens-Universitat Graz); Bakker, M. (TU Delft Water Resources); Klammler, Gernot (JR-AquaConSol GMHB); Birk, Steffen (Karl-Franzens-Universitat Graz)","","2021","The estimation of groundwater recharge is of paramount importance to assess the sustainability of groundwater use in aquifers around the world. Estimation of the recharge flux, however, remains notoriously difficult. In this study the application of nonlinear transfer function noise (TFN) models using impulse response functions is explored to simulate groundwater levels and estimate groundwater recharge. A nonlinear root zone model that simulates recharge is developed and implemented in a TFN model and is compared to a more commonly used linear recharge model. An additional novel aspect of this study is the use of an autoregressive-moving-average noise model so that the remaining noise fulfills the statistical conditions to reliably estimate parameter uncertainties and compute the confidence intervals of the recharge estimates. The models are calibrated on groundwater-level data observed at the Wagna hydrological research station in the southeastern part of Austria. The nonlinear model improves the simulation of groundwater levels compared to the linear model. The annual recharge rates estimated with the nonlinear model are comparable to the average seepage rates observed with two lysimeters. The recharges estimates from the nonlinear model are also in reasonably good agreement with the lysimeter data at the smaller timescale of recharge per 10 d. This is an improvement over previous studies that used comparable methods but only reported annual recharge rates. The presented framework requires limited input data (precipitation, potential evaporation, and groundwater levels) and can easily be extended to support applications in different hydrogeological settings than those presented here.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:c443e956-f18d-4444-a770-b7e5b208fee3","http://resolver.tudelft.nl/uuid:c443e956-f18d-4444-a770-b7e5b208fee3","Faults in consumer products are difficult to diagnose, and design is to blame: A user observation study","Pozo Arcos, B. (TU Delft Circular Product Design); Dangal, S. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Faludi, Jeremy (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2021","The process of fault diagnosis is an essential first step when repairing a product: it determines the condition of the parts and identifies the origin of failure. We report on how product users go through the process of fault diagnosis in consumer products and the influence of design features on this process. Two groups of 12 participants were asked to determine the fault in a defective product we supplied; the groups differed in their self-reported repair expertise. Four types of products were used for the study: a vacuum cleaner, kitchen blender, radio CD player, and coffee maker. During the experiment, the participants were asked to think aloud to explain their actions and understandings. Afterwards, they were interviewed regarding their experience. The results from the verbal and video analysis provided input for an updated framework of the diagnosis process, describing user actions at each
diagnosis stage. Furthermore, we show that the way a product is designed and constructed (the positioning, accessibility, and visibility of relevant product components) has a significant influence on the success of the fault
diagnosis. An important factor is user experience: product use facilitates signal recognition, while repair expertise facilitates disassembly. However, user experience is still less influential than the product’s design. Based on these findings, we propose a set of design guidelines to facilitate the process of fault diagnosis in consumer products","Circular economy; Consumer products; Fault diagnosis; Product design; Repair; Troubleshooting","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:0ff618e4-ac35-49d1-be46-b94514d0858f","http://resolver.tudelft.nl/uuid:0ff618e4-ac35-49d1-be46-b94514d0858f","Strong Reduction of the Chain Rigidity of Hyaluronan by Selective Binding of Ca2+ Ions","Giubertoni, Giulia (AMOLF); Pérez De Alba Ortíz, Alberto (Universiteit van Amsterdam); Bano, Fouzia (University of Leeds); Zhang, Xing (Rensselaer Polytechnic Institute); Linhardt, Robert J. (Rensselaer Polytechnic Institute); Green, Dixy E. (University of Oklahoma); Deangelis, Paul L. (University of Oklahoma); Koenderink, G.H. (TU Delft BN/Gijsje Koenderink Lab; Kavli institute of nanoscience Delft); Richter, Ralf P. (University of Leeds); Ensing, Bernd (Universiteit van Amsterdam); Bakker, Huib J. (AMOLF)","","2021","The biological functions of natural polyelectrolytes are strongly influenced by the presence of ions, which bind to the polymer chains and thereby modify their properties. Although the biological impact of such modifications is well recognized, a detailed molecular picture of the binding process and of the mechanisms that drive the subsequent structural changes in the polymer is lacking. Here, we study the molecular mechanism of the condensation of calcium, a divalent cation, on hyaluronan, a ubiquitous polymer in human tissues. By combining two-dimensional infrared spectroscopy experiments with molecular dynamics simulations, we find that calcium specifically binds to hyaluronan at millimolar concentrations. Because of its large size and charge, the calcium cation can bind simultaneously to the negatively charged carboxylate group and the amide group of adjacent saccharide units. Molecular dynamics simulations and single-chain force spectroscopy measurements provide evidence that the binding of the calcium ions weakens the intramolecular hydrogen-bond network of hyaluronan, increasing the flexibility of the polymer chain. We also observe that the binding of calcium to hyaluronan saturates at a maximum binding fraction of ∼10-15 mol %. This saturation indicates that the binding of Ca2+ strongly reduces the probability of subsequent binding of Ca2+ at neighboring binding sites, possibly as a result of enhanced conformational fluctuations and/or electrostatic repulsion effects. Our findings provide a detailed molecular picture of ion condensation and reveal the severe effect of a few, selective and localized electrostatic interactions on the rigidity of a polyelectrolyte chain.","","en","journal article","","","","","","","","","","","BN/Gijsje Koenderink Lab","","",""
"uuid:a5c78daa-48a0-4d46-ada5-93fdc7c003fc","http://resolver.tudelft.nl/uuid:a5c78daa-48a0-4d46-ada5-93fdc7c003fc","Key competencies for design in a circular economy: Exploring gaps in design knowledge and skills for a circular economy","Sumter, Deborah (TU Delft Circular Product Design); de Koning, J.I.J.C. (TU Delft Design for Sustainability); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2021","In a recent study, we identified seven key circular competencies for design: (1) Design for Multiple Use Cycles, (2) Design for Recovery, (3) Circular Impact Assessment, (4) Circular Business Models, (5) Circular User Engagement, (6) Circular Economy Collaboration, and (7) Circular Economy Communication. These were derived from small‐scale studies with designers working in the Netherlands. We set out to assess to what extent this set of seven competencies is recognized by an international group of designers and to evaluate whether any competencies are missing. We used an online survey to collect data from 128 respondents from 25 countries working on circular economy projects. The survey results showed that respondents use and have expertise in all seven competencies and they stressed the practical importance of two new competencies: Circular Systems Thinking and Circular Materials and Manufacturing. The resulting set of nine key competencies is the first internationally verified, coherent set of key circular economy competencies for design. This set will strengthen the pedagogical base of design for a circular economy and will guide the development of circular design methodology.","Circular design; Circular economy; Competencies; Design education; Product design; Sustainability","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:d62cca36-a229-4b95-8275-9a90f7cc166c","http://resolver.tudelft.nl/uuid:d62cca36-a229-4b95-8275-9a90f7cc166c","Inter-Organizational Co-Creation: An Approach to Support Energy Transition Projects","Jalali Sohi, A. (TU Delft Integral Design & Management); Rikhtegarnezami, M. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management); Hertogh, M.J.C.M. (TU Delft Integral Design & Management)","Cuevas, Roxana (editor); Bodea, Constanta-Nicoleta (editor); Torres-Lima, Pablo (editor)","2021","Societal challenges such as climate change and inefficiency of energysystems more and more crave for a sustainable environment. Research proved thatrestructuring energy systems into more sustainable forms, called “Energy Transition”, has faced challenges. How to deal with these challenges requires the cocreation between various actors with multiple disciplines, expertise, and perspectivesfrom different organizations. The research question to be answered here is whetherco-creation helps the interaction between different actors in an inter-organizationalproject for the sake of better project results. By doing case study research in theNetherlands, an example of co-creation project in its front-end phase was investigatedregarding the interaction among different actors involved in the project. The researchrevealed that in the case of a co-creation project the multiple actors collaborate acrossorganizational boundaries in order to unite. This leads to a better solution-findingapproach. Openness, trust and respect are valued more in co-creation. Moreover,the project team is better integrated to work towards a shared interest which aresocial benefits. The co-creation facilitated the data-sharing among the key actorsin the project which traditionally is influenced highly by the mother-organizations’culture. Further research will investigate the transition in organizations to supportthe co-creation approach.","Energy transition; Co-creation; Inter-organizational projects; Collaboration","en","conference paper","Springer","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2021-06-18","","","Integral Design & Management","","",""
"uuid:65ee256d-f697-4de1-8ac6-6065a61b1f70","http://resolver.tudelft.nl/uuid:65ee256d-f697-4de1-8ac6-6065a61b1f70","Propagation mechanism of reverse bias induced defects in Cu(In,Ga)Se2 solar cells","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices; TNO); Åhman, Hanna Nilsson (TNO); Burgers, Teun (ECN Solar Energy); Barreau, Nicolas (Université de Nantes); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; ECN Solar Energy); Theelen, Mirjam (TNO)","","2020","Partial shading of monolithically interconnected Cu(In,Ga)Se2 (CIGSe) modules can lead to the formation of reverse bias induced defects. These localized defects permanently reduce the output of the PV module. The formation and propagation mechanisms of these defects is studied. Understanding these mechanisms can help to prevent or mitigate damage due to partial shading of CIGSe PV modules. A propagation mechanism is proposed based on both compositional changes found at the edges of the reverse bias induced defects and differences in observed propagation patterns caused by the lateral voltage drop over the TCO layer.","CIGS; Partial shading; Propagation mechanism; Reverse bias; TCO; Wormlike defects","en","journal article","","","","","","Accepted author manuscript","","2021-10-29","","","Photovoltaic Materials and Devices","","",""
"uuid:c666d776-fc11-44b8-bc97-0e1f9243c115","http://resolver.tudelft.nl/uuid:c666d776-fc11-44b8-bc97-0e1f9243c115","Design for divestment in a circular economy: Stimulating voluntary return of smartphones through design","Poppelaars, F.A.; Bakker, C.A. (TU Delft Circular Product Design); van Engelen, J.M.L. (TU Delft Design for Sustainability; Rijksuniversiteit Groningen)","","2020","For the transition toward a circular economy, it is essential that products are returned for reuse, refurbishing or recycling. In order to address the lack of literature on the topic from a user perspective, this paper explores how users can be stimulated to return used smartphones. Taking a Research through Design approach, we developed a novel set of ""design for divestment"" principles. Divestment is the process users experience when separating from a product. After introducing a conceptual model of divestment based on an extension of the Consumer Decision Process model by Blackwell, Engel, and Miniard, we describe seven empirical studies (i.e., design projects) into smartphone divestment. The studies explore factors that influence a successful divestment process. We report on a highly complex process with interrelated factors changing over time. While it is impossible to define a blueprint for an ideal divestment process, several patterns emerged such as the need to emotionally support users, to give them confidence regarding data security, and to provide information at the right moment. These unique insights contribute to consumer research (i.e., circular consumption); and by translating the insights to ten design principles for divestment, a novel contribution is made to the field of design research.","Circular economy; Collection; Consumer behaviour; Design for a circular economy; Detachment; Disposition; Divestment; End of use; End-of-life; User","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:618f4557-c50f-4091-9160-54c9903793ae","http://resolver.tudelft.nl/uuid:618f4557-c50f-4091-9160-54c9903793ae","Seagrass coastal protection services reduced by invasive species expansion and megaherbivore grazing","James, Rebecca K. (Universiteit Utrecht; Rijksuniversiteit Groningen; NIOZ Royal Netherlands Institute for Sea Research); Christianen, Marjolijn J.A. (Wageningen University & Research); van Katwijk, Marieke M. (Radboud Universiteit Nijmegen); de Smit, Jaco C. (Universiteit Utrecht; NIOZ Royal Netherlands Institute for Sea Research); Bakker, Elisabeth S. (Netherlands Institute of Ecology; Wageningen University & Research); Herman, P.M.J. (TU Delft Environmental Fluid Mechanics); Bouma, T.J. (TU Delft Environmental Fluid Mechanics; NIOZ Royal Netherlands Institute for Sea Research; Universiteit Utrecht; Rijksuniversiteit Groningen)","","2020","Seagrasses provide an important ecosystem service by creating a stable erosion-resistant seabed that contributes to effective coastal protection. Variable morphologies and life-history strategies, however, are likely to impact the sediment stabilization capacity of different seagrass species. We question how opportunistic invasive species and increasing grazing by megaherbivores may alter sediment stabilization services provided by established seagrass meadows, using the Caribbean as a case study. Utilizing two portable field-flumes that simulate unidirectional and oscillatory flow regimes, we compared the sediment stabilization capacity of natural seagrass meadows in situ under current- and wave-dominated regimes. Monospecific patches of a native (Thalassia testudinum) and an invasive (Halophila stipulacea) seagrass species were compared, along with the effect of three levels of megaherbivore grazing on T. testudinum: ungrazed, lightly grazed and intensively grazed. For both hydrodynamic regimes, the long-leaved, dense meadows of the climax species, T. testudinum provided the highest stabilization. However, the loss of above-ground biomass by intensive grazing reduced the capacity of the native seagrass to stabilize the surface sediment. Caribbean seagrass meadows are presently threatened by the rapid spread of the invasive opportunistic seagrass, H. stipulacea. The dense meadows of H. stipulacea were found to accumulate fine sediment, and thereby, appear to be effective in reducing bottom shear stress during calm periods. This fine sediment within the invasive meadows, however, is easily resuspended by hydrodynamic forces, and the low below-ground biomass of H. stipulacea make it susceptible to uprooting during storm events, potentially leaving large regions vulnerable to erosion. Overall, this present study highlights that intensive megaherbivore grazing and opportunistic invasive species threaten the coastal protection services provided by mildly grazed native species. Synthesis. Seagrass meadows of dense, long-leaved species stabilize the sediment surface and maintain the seabed integrity, thereby contributing to coastal protection. These services are threatened by intensive megaherbivore grazing, which reduces the stability of the surface sediment, and opportunistic invasive species, which are susceptible to uprooting in storms and thereby can leave the seabed vulnerable to erosion.","coastal protection; conservation; ecosystem services; exotic species; marine ecology; marine vegetation; storm resilience; tropical ecology","en","journal article","","","","","","","","","","","Environmental Fluid Mechanics","","",""
"uuid:df8f9419-9aec-481f-a1ee-f18e24d9fa64","http://resolver.tudelft.nl/uuid:df8f9419-9aec-481f-a1ee-f18e24d9fa64","Evaluation Of Managerial Flexibilities In Critical Path Method Based Construction Schedules","Ökmen, Ö. (TU Delft Integral Design & Management); Bosch-Rekveldt, M.G.C. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2020","Scheduling of a construction project can be done by using the Critical Path Method (CPM) in case the project is composed of interrelated activities that can be combined through a network. Given uncertainties nowadays and the related need for project schedule adaptations, the question is raised whether and how “traditional” CPM based schedules allow for flexibility in project planning and management.
In order to give an answer to this question, firstly the managerial flexibilities provided by CPM were evaluated at three levels, i.e. activity, path, and project. Afterwards, the CPM schedules of two different projects were examined. Finally, the first conclusion arrived was that, in spite of its criticized deterministic features, CPM contains various flexible aspects from a managerial viewpoint. Second, potential flexibilities in CPM are mainly associated with resource levelling, uncritical activities, uncritical paths, activity float times, activity float types, and float times of uncritical paths. Third, CPM contains complete flexibility through independent floats and resource levelling capability.
Investigating the flexible features of CPM in its traditional form, this study aims to open the way to develop a more flexible scheduling approach based on CPM and its extensions, which future self-organizing teams can adjust or apply.","Activity criticality; Activity float times; Activity float types; Critical path method; Flexible schedule management","en","conference paper","IPMA","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2021-04-01","","","Integral Design & Management","","",""
"uuid:33c41613-3d15-42df-b62d-80b42af98bc1","http://resolver.tudelft.nl/uuid:33c41613-3d15-42df-b62d-80b42af98bc1","Calibration of a simple 1D model for the hydraulic response of regional dykes in the Netherlands","Chao, C. (TU Delft Geo-engineering); Bakker, M.C.M. (TU Delft Resources & Recycling); Jommi, C. (TU Delft Geo-engineering; Politecnico di Milano)","","2020","A simple numerical model was set up to investigate the hydraulic behaviour of a regional dyke to improve understanding of the response under variable atmospheric conditions. The unsaturated hydraulic properties of the dyke body and the relevant foundation layers were calibrated either on the results of laboratory tests or on a national database, namely the Staringreeks, compiled for typical Dutch soils. The boundary conditions were imposed according to the weather history at the top, and to the pore pressures measured in the field at the bottom of the representative soil column. The results indicate that a simple 1D model is able to accurately reproduce the suction time history in the dyke core, provided the hydraulic conductivity and soil water retention properties are properly calibrated. The optimised hydraulic conductivities are typically two orders of magnitude higher than the saturated hydraulic conductivity from the laboratory tests, but comparable to the ones suggested in the database developed on field data. The work highlights that cautious evaluation of laboratory data is needed for field applications, and that direct information from the field should be used to validate numerical models in the presence of organic soils.","","en","journal article","","","","","","","","","","","Geo-engineering","","",""
"uuid:f644cf86-8c89-4cd2-839e-4bd6e9c65692","http://resolver.tudelft.nl/uuid:f644cf86-8c89-4cd2-839e-4bd6e9c65692","The challenges faced in the reverse logistics of automotive cores: lessons from co-creation with stakeholders.","van Dam, S.S. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Hoogeveen, L.A.J. (Student TU Delft)","","2020","This paper presents the results of two co-creation sessions with stakeholders in the automotive aftermarket. The sessions were instigated as part of the EU project ReCiPSS to develop a new service to simplify the reverse logistics of automotive cores purposed for remanufacturing. Remanufacturing car parts is a longstanding practice within the automotive aftermarket. Over the last fifty years a mature, but also highly complex, market has developed. The reverse logistics of these cores substantially increases the complexity and costs of the remanufacturing process due to the fact that they are repeatedly shipped, handled, (re)identified and (re)assessed for quality and their remanufacturability by different actors within the supply chain. This is due to the fact that most cores are returned along the exact same route that the (remanufactured) replacement part took in the forward logistics, using a so called ‘surcharge’ or ‘deposit’ system. Core broker networks are used to fill in the gaps where not enough cores are coming in through the surcharge system. Together, this forms a complicated network. The current setup has benefits, e.g. with regards to customer relationships and higher return rates, but also provides the necessary challenges. To identify these benefits and challenges, as well as the needs of different stakeholders within the supply chain, a series of co-creation sessions were held with different actors. This paper presents the results of two sessions. This first was with a wholesaler, the second with several core brokers and a service provider. New insights were gained on the landscape of reverse logistics of automotive cores and the challenges different stakeholders are facing. These are presented in the paper in graphic overviews. Challenges include a lack of transparency and traceability leading to distrust, poor identification possibilities of cores, as well as threats from cheap infill and copies. With these results, new value propositions for the different stakeholders were developed. These were used to design and pilot an online platform together with a single service provider. The platform aims to benefit the different stakeholders while simultaneously reducing the complexity of the reverse logistics by identifying and evaluating cores only once before being directly shipped to their final destination. The paper concludes by highlighting the opportunities and challenges that the remanufacturing market is facing, based on the insights gathered from different stakeholders, and the implications for the future of the remanufacturing industry and policy.","co-creation; automotive cores; reverse logistics; wholesalers; core brokers","en","conference paper","","","","","","","","","","","Circular Product Design","","",""
"uuid:45ad9f7f-c6cc-4660-b7ef-4ba426ea0422","http://resolver.tudelft.nl/uuid:45ad9f7f-c6cc-4660-b7ef-4ba426ea0422","'Iouδαíαν in Acts 2:9: Reverse engineering textual emendations","van Altena, V.P. (TU Delft Urban Data Science; Vrije Universiteit Amsterdam); Krans, Jan (Protestantse Theologische Universiteit); Bakker, Henk (Vrije Universiteit Amsterdam); Stoter, J.E. (TU Delft Urban Data Science)","","2020","Building on a plethora of conjectured emendations for IOÏ'ΔAIAN, this article approaches the issue once again to test the viability of a quantitative tool and to establish the possibility of palaeographical confusion of IOÏ'ΔAIAN with an alternative topo- or demonym. The article starts with an experiment using Greek topo- and demonyms derived from contemporary Christian, Jewish, and Classical sources to establish a palaeographical confusion score. Next the likeliness of the ""closest""alternatives in the geographical arrangement of Acts 2:9-11 is explored. The article ends with an evaluation of the possible implications for the text in Acts 2:9 as well as a critical appraisal of the method for conjectural criticism.","Conjectural criticism; Palaeographic confusion; Spatial analysis; Table of nations","en","journal article","","","","","","","","","","","Urban Data Science","","",""
"uuid:56ceff9e-54c9-464b-a0e4-58fe7396d471","http://resolver.tudelft.nl/uuid:56ceff9e-54c9-464b-a0e4-58fe7396d471","Hotspot Mapping for product disassembly: A circular product assessment method","Flipsen, Bas (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); de Pauw, I.C. (TU Delft Circular Product Design)","Schneider-Ramelow, Martin (editor)","2020","Designing products for the Circular Economy requires closing and slowing of loops by means of repair, reman-ufacturing, refurbishment, parts reuse and/or recycling. Ease of product disassembly facilitates these processes to be more cost-effective, resulting in a better circular strategy fit. In this paper we present the Hotspot Map-ping method. The objective of this method is to help designers in (re)designing their products for ease of disas-sembly, by assessing which parts in the product architecture are most critical for ease of disassembly. Critical parts are parts with a high failure rate or maintenance need and/or with a high economic and environmental value, that should be easily accessible with low effort to enable cost-effective recovery processes. A product’s ease of disassembly is determined by factors that help or hinder the disconnection of critical parts from the rest of the product. The Hotspot Mapping method is a spreadsheet-based tool that indicates ease-of-disassembly by flagging five ‘hotspot’ indicators: (i) time needed to disconnect parts, (ii) difficulty of access, (iii) priority parts, (iv) environmental impact and (v) economy valuable parts. The Hotspot Mapping method adds to recent repairability assessment methods proposed in standards such as EN45554:2020, by also taking into account other aspects than failure-rate and functionality, such as economic and environmental value of the parts and materials. This paper describes the Hotspot Mapping method and applies the method to a household blender.","electronics; product; assessment; circular; repair; Design capacity efficiency; circular economy","en","conference paper","","","","","","","","","","","Circular Product Design","","",""
"uuid:acfe7366-008c-4a9d-b44f-d1002fdc53e2","http://resolver.tudelft.nl/uuid:acfe7366-008c-4a9d-b44f-d1002fdc53e2","Iouδαíαν in Acts 2:9: a Diachronic Overview of its Conjectured Emendations","van Altena, V.P. (TU Delft Urban Data Science; Vrije Universiteit Amsterdam); Krans, Jan (Protestantse Theologische Universiteit); Bakker, Henk (Vrije Universiteit Amsterdam); Stoter, J.E. (TU Delft Urban Data Science)","","2020","The appearance of ουδα » αν in the table of nations (Acts 2:9-11) has troubled interpreters for centuries. Several scholars have proposed to emendate the text. The argumentations for such conjectures vary in elaboration and support. This article gives a diachronic overview of the conjectured emendations. It concludes with an evaluation of the discussion from a phenomenological perspective and a summary of the used argumentation, thereby providing input for a reversed engineering approach to the issue.","Conjectural criticism; Palaeographic confusion; Spatial analysis; Table of nations","en","review","","","","","","","","","","","Urban Data Science","","",""
"uuid:02c42772-af3b-49d8-91ff-1cdb52d2080e","http://resolver.tudelft.nl/uuid:02c42772-af3b-49d8-91ff-1cdb52d2080e","Probabilistic life cycle cash flow forecasting with price uncertainty following a geometric Brownian motion","van den Boomen, M. (TU Delft Integral Design & Management; Rotterdam University of Applied Sciences); Bakker, H.L.M. (TU Delft Integral Design & Management); Schraven, D.F.J. (TU Delft Integral Design & Management); Hertogh, M.J.C.M. (TU Delft Integral Design & Management)","","2020","In the Netherlands, probabilistic life cycle cash flow forecasting for infrastructures has gained attention in the past decennium. Frequencies, volume and unit prices of life cycle activities are treated as uncertainty variables for which an expert-based triangular distribution is assumed. The current research observes the absence of time-variant variables typical for infrastructure life cycles among which price (de-)escalation. Moreover, previous research has shown that price (de-)escalation and its uncertainty should not be ignored as it may lead to over or underestimation of costs, especially for public sector organisations which use low discount rates. For that reason, the current research has searched for a more data-driven approach to include price (de-)escalation and its uncertainty by adopting a price forecasting method from the financial domain, a Geometric Brownian Motion. The uncertainty variables drift and volatility are obtained from publicly available price indices. This approach is easily included in the current practice for probabilistic cost forecasting which is demonstrated on a case study. The case study shows that ignoring price increases may lead to an underestimation of total discounted costs of 13%. From an academic perspective, the current research advocates inclusion of price uncertainty in multi-objective optimisation modelling of infrastructure life cycle activities.","Cash flow; Geometric Brownian Motion; forecasting; infrastructure; life cycle; probabilistic","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:91a5961e-baf7-401b-8755-7a3fe4e463a6","http://resolver.tudelft.nl/uuid:91a5961e-baf7-401b-8755-7a3fe4e463a6","The embodiment of low-field MRI for the diagnosis of infant hydrocephalus in Uganda","Diehl, J.C. (TU Delft Design for Sustainability); van Doesum, F. (Student TU Delft); Bakker, M.F. (TU Delft Design for Sustainability); van Gijzen, M.B. (TU Delft Numerical Analysis); O’Reilly, Thomas (Leiden University Medical Center); Muhumuza, Ivan (Mbarara University of Science and Technology); Obungoloch, Johnes (Mbarara University of Science and Technology); Kabachelor, Edith Mbabazi (CURE Hospital, Mbale)","Cunningham, Paul M. (editor)","2020","class=""MsoNormal"">Compared to other parts of the world, the incidence of hydrocephalus in children is very high in sub- Saharan Africa. Magnetic resonance imaging (MRI) would be the preferred diagnostic method for infant hydrocephaleus. However, in practice, MRI is seldom used in sub-Saharan Africa due to its high prize, low mobility, and high power consumption. A low-cost MRI technology is under development by reducing the strength of the magnetic field and the use of alternative technologies to create the magnetic field. This paper describes the embodiment design process to match this new MRI technology under development with the specific characteristics of thehealthcare system in Uganda. A context exploration was performed to identify factors that may affect the design and implementation of the low-field MRI in Ugandan hospitals and Ugandan healthcare environment. The key-insights from the technology- and context-exploration were translated into requirements which were the starting point for the design process. The concept development did have a focus on Cost-effective design, Design for durability & reliability, and Design for repairability. The final design was validated by stakeholders from the Ugandan Healthcare context","Neglected tropical disease; schistosomiasis; global health; diagnostics; local production; technical optics; algorithms; artificial intelligence; Nigeria","en","conference paper","IEEE","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2021-11-02","","","Design for Sustainability","","",""
"uuid:7a0c1382-d666-4bdf-9bdb-b3a4c151e365","http://resolver.tudelft.nl/uuid:7a0c1382-d666-4bdf-9bdb-b3a4c151e365","How the absorber thickness influences the formation of reverse bias induced defects in CIGS solar cells","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices; TNO); Rasia, Alix (TNO); Assen, Suzanne (TNO); Aflouat, Basma Ben Said (TNO); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; TNO); Theelen, Mirjam (TNO)","","2020","When a PV module is partially shaded, the shaded solar cells operate in a reverse bias condition. For Cu(In,Ga)Se2 cells this condition can cause defects that irreversibly reduce the output of these cells and the full module. In order to design robust shade-tolerant CIGS modules details need to be known of the conditions at which these defects will be formed. In this study a large number of cells were exposed to different reverse bias conditions. By using simple statistics the probability of the occurrence of defects as a result of reverse bias at any given voltage has been determined. Based on our experiments we have found that the absorber thickness is one of the main parameters that affects the shade-tolerance: the thicker the absorber, the more shade tolerant the CIGS module will be.","CIGS; Partial shading; Reliability; Reverse bias; Wormlike defects; OA-Fund TU Delft","en","journal article","","","","","","","","","","","Photovoltaic Materials and Devices","","",""
"uuid:f249f95d-ddf7-4384-b8ec-dc8fdce60351","http://resolver.tudelft.nl/uuid:f249f95d-ddf7-4384-b8ec-dc8fdce60351","The ideal type of valuer: expert, service provider or reporter? An investigation into prevailing role types in commercial valuation","Klamer, Pim (Hogeschool Utrecht; Universiteit Utrecht); Gruis, V.H. (TU Delft Management in the Built Environment); Bakker, Cok (Universiteit Utrecht)","","2020","Purpose: The purpose of this paper aims to disclose shared beliefs and understandings about the concept of professionalism amongst Dutch commercial real estate valuers. It examines prevailing logics of action in a mature European valuation industry and reflects on the potential influence of these logics on the occurrence of judgement bias in valuation. Design/methodology/approach: The underlying study adopted a grounded theory approach to facilitate reflexive in-depth interview sessions with 20 experienced valuation professionals in the Netherlands. Emerging data on core categories of professionalism were initially identified and grouped; and subsequently conceptualised into ideal role types of valuers using institutional logics theory. Findings: Three different ideal types appear to guide Dutch valuation practice: the expert, the service provider and the reporter. The expert emphasises professional standards and technical quality, while the service provider advocates commercial quality and the reporter aims to uphold procedural quality. The authors find that the attention for technical quality associated with the expert role may be at risk of underexposure, fostering concerns about judgement quality and associated bias risks. Research limitations/implications: The potential impact of both commercial and bureaucratic logics on valuation quality may raise authoritative and educational concerns over judgement bias effects. However, while trends in professionalism may transcend national boundaries, the specifics of local real estate market structures and regulations require replication of results in other markets. Originality/value: Institutional logics provide an alternative, socio-economic perspective on present-day valuer behaviour that progresses the understanding of the valuer–client relationship, thereby advancing the knowledge base on valuer judgement and client influence. Furthermore, the authors' role typology offers future research opportunities in terms of measurement and explanation of differences.","Asset valuation; Behaviour; Professional services; The Netherlands","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2021-06-04","","Management in the Built Environment","","","",""
"uuid:a5e02138-ca28-44fb-af60-6e633b4a6c48","http://resolver.tudelft.nl/uuid:a5e02138-ca28-44fb-af60-6e633b4a6c48","Practices of fault diagnosis in household appliances: Insights for design","Pozo Arcos, B. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Flipsen, Bas (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2020","Fault diagnosis is the process of identifying and characterising a fault when a failure occurs. It is, therefore, an essential step to take before product-repair. In this study, we ask how conventional users diagnose faults in household appliances and how the design of these appliances facilitates or hampers the process of fault diagnosis.To investigate this we qualitatively analyse the content of iFixit's online repair forum for three products: kitchen blenders, vacuum cleaners, and refrigerators. First, we develop a conceptual analysis framework based on the literature. Second, using conventional content analysis, we correlate facilitating and hampering features with the appliances’ design. The process of fault diagnosis can be described by the subsequent actions of fault detection, fault location and fault isolation. Our results show that consumers detect faults by noticing five types of symptoms. Subsequently, two distinct diagnosis approaches can be distinguished. One follows a trial and error approach where the user performs diagnosis actions which usually result in replacing a potentially defective component until the symptoms disappear. The other occurs when the symptoms are error codes; the defective part can be more accurately identified, and the diagnosis is straightforward. The results also show that appliances are not designed to make fault diagnosis easy. Access to and visibility of components are often blocked, making fault isolation challenging. User manuals commonly lack relevant explanations, for instance when symptoms are different from error codes. Based on these findings, we propose a number of design recommendations to facilitate fault diagnosis for household appliance users.","Circular economy; Design guidelines; Fault diagnosis; Product design; Repair; Troubleshooting","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:7ab2191d-9295-4d78-ada8-3054f8ebe078","http://resolver.tudelft.nl/uuid:7ab2191d-9295-4d78-ada8-3054f8ebe078","Studying Chemisorption at Metal-Polymer Interfaces by Complementary Use of Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) in the Kretschmann Geometry and Visible-Infrared Sum-Frequency Generation Spectroscopy (SFG)","Fockaert, L.I. (TU Delft (OLD) MSE-6; Netherlands Organization for Scientific Research); Ganzinga-Jurg, Deborah (Tata Steel); Versluis, Jan (AMOLF); Boelen, Berend (Tata Steel); Bakker, Huib J. (AMOLF); Terryn, H.A. (Vrije Universiteit Brussel); Mol, J.M.C. (TU Delft (OLD) MSE-6)","","2020","The molecular configuration and chemistry at the zinc/zinc oxide-polyester interface were studied by using two complementary spectroscopic techniques: attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and sum-frequency generation (SFG) spectroscopy. It was shown that ATR-FTIR should be considered as a (3D) interphase-sensitive technique with probing depths of 250-400 nm in the headgroup region (2000-1200 cm-1). On the other hand, SFG is known to be a (2D) interface-sensitive technique. The ATR-FTIR measurements showed that carboxylate groups are formed within the near-interface region of the polyester phase. SFG measurements showed that the carboxylic acid groups are stable at the polymer-zinc/zinc oxide interface. In addition, in situ ATR-FTIR and SFG measurements have been conducted when exposing the polyester-zinc/zinc oxide system to D2O. The exposure to D2O is observed to lead to an additional conversion of ester and carboxylic acid groups to carboxylate groups. The comparison of the SFG and ATR-FTIR measurements shows that this conversion occurs much slower at the polyester-zinc/zinc oxide interface than in the bulk of the polyester. Finally, the strengths and limitations as well as the complementarity of both techniques are discussed.","Interfaces; Oxides; Nonlinear optics; Organic polymers; Infrared light","en","journal article","","","","","","","","","","","(OLD) MSE-6","","",""
"uuid:b69e99af-b5c8-47b9-abb8-cec7fb68fa6d","http://resolver.tudelft.nl/uuid:b69e99af-b5c8-47b9-abb8-cec7fb68fa6d","Estimation of temperature and associated uncertainty from fiber-optic raman-spectrum distributed temperature sensing","des Tombe, B.F. (TU Delft Water Resources); Schilperoort, B. (TU Delft Water Resources); Bakker, M. (TU Delft Water Resources)","","2020","Distributed temperature sensing (DTS) systems can be used to estimate the temperature along optic fibers of several kilometers at a sub-meter interval. DTS systems function by shooting laser pulses through a fiber and measuring its backscatter intensity at two distinct wavelengths in the Raman spectrum. The scattering-loss coefficients for these wavelengths are temperature-dependent, so that the temperature along the fiber can be estimated using calibration to fiber sections with a known temperature. A new calibration approach is developed that allows for an estimate of the uncertainty of the estimated temperature, which varies along the fiber and with time. The uncertainty is a result of the noise from the detectors and the uncertainty in the calibrated parameters that relate the backscatter intensity to temperature. Estimation of the confidence interval of the temperature requires an estimate of the distribution of the noise from the detectors and an estimate of the multi-variate distribution of the parameters. Both distributions are propagated with Monte Carlo sampling to approximate the probability density function of the estimated temperature, which is different at each point along the fiber and varies over time. Various summarizing statistics are computed from the approximate probability density function, such as the confidence intervals and the standard uncertainty (the estimated standard deviation) of the estimated temperature. An example is presented to demonstrate the approach and to assess the reasonableness of the estimated confidence intervals. The approach is implemented in the open-source Python package “dtscalibration”.","Calibration; Confidence intervals; Distributed temperature sensing; DTS; Fiber optic; Raman; Stokes; Temperature; Uncertainty","en","journal article","","","","","","Corrigendum: DOI 10.3390/s21030912. The original article has been updated.","","","","","Water Resources","","",""
"uuid:57153b29-1ca9-431b-9804-bd4a1b51e7b2","http://resolver.tudelft.nl/uuid:57153b29-1ca9-431b-9804-bd4a1b51e7b2","Analysis of SESANS data by numerical Hankel transform implementation in SasView","Bakker, J.H. (TU Delft RST/Radiation, Science and Technology; TU Delft RST/Neutron and Positron Methods in Materials); Washington, Adam L. (Rutherford Appleton Laboratory); Parnell, S.R. (TU Delft RID/TS/Instrumenten groep; TU Delft RST/Radiation, Science and Technology); van Well, A.A. (TU Delft RID/Algemeen/Bedrijfsondersteuning; TU Delft RST/Radiation, Science and Technology); Pappas, C. (TU Delft RST/Neutron and Positron Methods in Materials; TU Delft RST/Radiation, Science and Technology); Bouwman, W.G. (TU Delft RST/Neutron and Positron Methods in Materials; TU Delft RST/Radiation, Science and Technology)","","2020","SESANS data analysis has been implemented in the SasView software package, allowing SESANS experiments to be analyzed using a numerical Hankel transformation of isotropic small-angle scattering (SAS) models. The error of the numerical approximation is three orders of magnitude below typical experimental errors. All advanced data fitting features of SasView (multi-model fitting, batch fitting, and simultaneous/constrained fitting) are now also available for SESANS and this is demonstrated by examples of fitting SAS models to SESANS measurements.","Hankel transform; neutrons; SANS; SasView; SESANS; Small-angle scattering","en","journal article","","","","","","","","","","RST/Radiation, Science and Technology","RST/Neutron and Positron Methods in Materials","","",""
"uuid:152d0656-f2bb-4d67-bf54-a40f01d31b26","http://resolver.tudelft.nl/uuid:152d0656-f2bb-4d67-bf54-a40f01d31b26","Characterization and hydrological analysis of the guarumales deep-seated landslide in the tropical ecuadorian andes","Urgilez Vinueza, A.R. (TU Delft Water Resources); Robles, Jessica (Hidropaute Business Unit, Corporación Eléctrica del Ecuador (CELEC EP)); Bakker, M. (TU Delft Water Resources); Guzman, Pablo (Hidropaute Business Unit, Corporación Eléctrica del Ecuador (CELEC EP); Universidad del Azuay); Bogaard, T.A. (TU Delft Water Resources)","","2020","The high landslide risk potential along the steep hillslopes of the Eastern Andes in Ecuador provides challenges for hazard mitigation, especially in areas with hydropower dams and reservoirs. The objective of this study was to characterize, understand, and quantify the mechanisms driving the motions of the Guarumales landslide. This 1.5 km2 deep-seated, slow-moving landslide is actively moving and threatening the “Paute Integral” hydroelectric complex. Building on a long time series of measurements of surface displacement, precipitation, and groundwater level fluctuations, we analyzed the role of predisposing conditions and triggering factors on the stability of the landslide. We performed an analysis of the time series of measured groundwater levels and drainage data using transfer functions. The geological interpretation of the landslide was further revised based on twelve new drillings. This demonstrated a locally complex system of colluvium deposits overlying a schist bedrock, reaching up to 100 m. The measured displacement rates were nearly constant at ~50 mm/year over the 18 years of study. However, the measurement accuracy and time resolution were too small to identify possible acceleration or deceleration phases in response to hydro-meteorological forcing. The groundwater and slope drainage data showed a lagged response to rainfall. Finally, we developed a conceptual model of the Guarumales landslide, which we hope will improve our understanding of the many other deep-seated landslides present in the Eastern Andes.","Deep-seated landslide; Ecuadorian Andes; Geodetical monitoring; Hydrogeological classification; Time series analysis","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:e72e5530-b8f8-4f40-8f37-c680d6589af6","http://resolver.tudelft.nl/uuid:e72e5530-b8f8-4f40-8f37-c680d6589af6","Hyaluronan biopolymers release water upon pH-induced gelation","van Dam, Eliane P. (AMOLF); Giubertoni, Giulia (AMOLF); Burla, Federica (AMOLF); Koenderink, G.H. (TU Delft BN/Gijsje Koenderink Lab; Kavli institute of nanoscience Delft; AMOLF); Bakker, Huib J. (AMOLF)","","2020","We study the relation between the macroscopic viscoelastic properties of aqueous hyaluronan polymer solutions and the molecular-scale dynamics of water using rheology measurements, differential dynamic microscopy, and polarization-resolved infrared pump-probe spectroscopy. We observe that the addition of hyaluronan to water leads to a slowing down of the reorientation of a fraction of the water molecules. Near pH 2.4, the viscosity of the hyaluronan solution reaches a maximum, while the number of slowed down water molecules reaches a minimum. This implies that the water molecules become on average more mobile when the solution becomes more viscous. This observation indicates that the increase in viscosity involves the expulsion of hydration water from the surfaces of the hyaluronan polymers, and a bundling of the hyaluronan polymer chains.","","en","journal article","","","","","","Accepted Author Manuscript","","2021-04-02","","","BN/Gijsje Koenderink Lab","","",""
"uuid:750df5f0-1b27-4cb4-b8c4-ec7bc9aced02","http://resolver.tudelft.nl/uuid:750df5f0-1b27-4cb4-b8c4-ec7bc9aced02","Assessing the transition effects in a drinking water distribution system caused by changing supply water quality: an indirect approach by characterizing suspended solids","Chen, L. (TU Delft Sanitary Engineering; Chinese Academy of Sciences); Ling, Fangqiong (Washington University in St. Louis); Bakker, Geo (Vitens N.V.); Liu, Wen Tso (University of Illinois at Urbana-Champaign); Medema, G.J. (Chinese Academy of Sciences; KWR Water Research Institute); van der Meer, W.G.J. (Oasen; University of Twente); Liu, G. (TU Delft Sanitary Engineering; Chinese Academy of Sciences)","","2020","Worldwide, it is common that the drinking water distribution systems (DWDSs) may be subjected to changes of supply water quality due to the needs of upgrading the treatment processes or switching the source water. However, the potential impacts of quality changed supply water on the stabilized ecological niches within DWDSs and the associated water quality deterioration risks were poorly documented. In the present study, such transition effects caused by changing the supply water quality that resulted from destabilization of biofilm and loose deposits in DWDS were investigated by analyzing the physiochemical and microbiological characteristics of suspended particles before (T0), during (T3-weeks) and after upgrading the treatments (T6-months) in an unchlorinated DWDS in the Netherlands. Our results demonstrated that after 6 months’ time the upgraded treatments significantly improved the water quality. Remarkably, water quality deterioration was observed at the initial stage when the quality-improved treated water distributed into the network at T3-weeks, observed as a spike of total suspended solids (TSS, 50–260%), active biomass (ATP, 95–230%) and inorganic elements (e.g. Mn, 130–250%). Furthermore, pyrosequencing results revealed sharp differences in microbial community composition and structure for the bacteria associated with suspended particles between T0 and T3-weeks, which re-stabilized after 6 months at T6-months. The successful capture of transition effects was especially confirmed by the domination of Nitrospira spp. and Polaromonas spp. in the distribution system at T3-weeks, which were detected at rather low relative abundance at treatment plant. Though the transitional effects were captured, this study shows that the introduction of softening and additional filtration did not have an effect on the water quality for the consumer which improved considerably after 6-months’ period. The methodology of monitoring suspended particles with MuPFiSs and additional analysis is capable of detecting transitional effects by monitoring the dynamics of suspended particles and its physiochemical and microbiological composition.","Drinking water distribution system; Suspended solids; Transition effects; Upgrading treatments; Water quality deterioration risks","en","journal article","","","","","","","","","","","Sanitary Engineering","","",""
"uuid:bd1d8edd-dbe5-4970-b82d-34fb2c8ecc0a","http://resolver.tudelft.nl/uuid:bd1d8edd-dbe5-4970-b82d-34fb2c8ecc0a","Variational Phase-Field Modeling of Hydraulic Fracture Interaction With Natural Fractures and Application to Enhanced Geothermal Systems","Lepillier, B.P. (TU Delft Reservoir Engineering); Yoshioka, Keita (Helmholtz Centre for Environmental Research - UFZ); Parisio, Francesco (University of Technology Bergakademie Freiberg); Bakker, R.R. (TU Delft Reservoir Engineering); Bruhn, D.F. (TU Delft Reservoir Engineering; Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences)","","2020","In every tight formation reservoir, natural fractures play an important role for mass and energy transport and stress distribution. Enhanced Geothermal Systems (EGS) make no exception, and stimulation aims at increasing the reservoir permeability to enhance fluid circulation and heat transport. EGS development relies upon the complex task of predicting accurate hydraulic fracture propagation pathway by taking into account reservoir heterogeneities and natural or preexisting fractures. In this contribution, we employ the variational phase-field method, which handles hydraulic fracture initiation, propagation, and interaction with natural fractures and is tested under varying conditions of rock mechanical properties and natural fractures distributions. We run bidimensional finite element simulations employing the open-source software OpenGeoSys and apply the model to simulate realistic stimulation scenarios, each one built from field data and considering complex natural fracture geometries in the order of a thousand of fractures. Key mechanical properties are derived from laboratory measurements on samples obtained in the field. Simulations results confirm the fundamental role played by natural fractures in stimulation's predictions, which is essential for developing successful EGS projects.","Enhanced Geothermal System; hydraulic fracture; natural fractures; phase field; stimulation","en","journal article","","","","","","","","","","","Reservoir Engineering","","",""
"uuid:b8c44b8b-e834-44ae-9699-e4d390475815","http://resolver.tudelft.nl/uuid:b8c44b8b-e834-44ae-9699-e4d390475815","Incorporating design for remanufacturing in the early design stage: a design management perspective","Boorsma, Nina (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Tsui, T.P.Y. (TU Delft Climate Design and Sustainability); Peck, David (TU Delft Climate Design and Sustainability)","","2020","Adopting design approaches that allow products to last multiple use-cycles supports European Commission objectives to reduce greenhouse gas emissions and reduce primary material impacts. Remanufacturing is an example of an appropriate circular strategy and it can be applied in a variety of industries that are intensive materials users. However, most companies have not yet adopted design strategies facilitating remanufacturing at scale. In this paper, we explored how design management can facilitate the implementation of Design for Remanufacturing, based on a literature review and in-depth interviews. Seven companies active in business-to-business markets were interviewed about the design-related opportunities and barriers they see for remanufacturing. We found that access to technical knowledge is not a barrier, whereas integrating this knowledge into the existing design process is. We conclude that design management can contribute to the uptake of Design for Remanufacturing for the following reasons: by making the value of Design for Remanufacturing to the company at large explicit, by building bridges between internal and external stakeholders, and by embedding Design for Remanufacturing into existing processes by means of Key Performance Indicators (KPIs) and roadmaps.","Circular product design; Closed loop supply chains; Design for Remanufacturing; Design management; Implementation; Multiple use-cycles; Product development","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:12ff7d97-7e79-4816-9d21-24cb24648a28","http://resolver.tudelft.nl/uuid:12ff7d97-7e79-4816-9d21-24cb24648a28","Connecting the Stimuli-Responsive Rheology of Biopolymer Hydrogels to Underlying Hydrogen-Bonding Interactions","Giubertoni, Giulia (AMOLF); Burla, Federica (AMOLF); Bakker, Huib J. (AMOLF); Koenderink, G.H. (TU Delft BN/Gijsje Koenderink Lab; Kavli institute of nanoscience Delft; AMOLF)","","2020","Many biopolymer hydrogels are environmentally responsive because they are held together by physical associations that depend on pH and temperature. Here, we investigate how the pH and temperature responses of the rheology of hyaluronan hydrogels are connected to the underlying molecular interactions. Hyaluronan is an essential structural biopolymer in the human body with many applications in biomedicine. Using two-dimensional infrared spectroscopy, we show that hyaluronan chains become connected by hydrogen bonds when the pH is changed from 7.0 to 2.5 and that the bond density at pH 2.5 is independent of temperature. Temperature-dependent rheology measurements show that because of this hydrogen bonding the stress relaxation at pH 2.5 is strongly slowed down in comparison to pH 7.0, consistent with the sticky reptation model of associative polymers. From the flow activation energy, we conclude that each polymer is cross-linked by multiple (5-15) hydrogen bonds to others, causing slow macroscopic stress relaxation, despite the short time scale of breaking and reformation of each individual hydrogen bond. Our findings can aid the design of stimuli-responsive hydrogels with tailored viscoelastic properties for biomedical applications.","","en","journal article","","","","","","","","","","","BN/Gijsje Koenderink Lab","","",""
"uuid:458da4c5-6142-41a5-87cc-da0f700ba6cc","http://resolver.tudelft.nl/uuid:458da4c5-6142-41a5-87cc-da0f700ba6cc","Circular economy competencies for design","Sumter, Deborah (TU Delft Circular Product Design); de Koning, J.I.J.C. (TU Delft Design for Sustainability); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2020","This study addresses what competencies (knowledge, skills, and attitudes) designers need in order to successfully design products and services for a circular economy. Existing literature, though sparse, has identified a number of circular economy competencies for design. Yet, a coherent overview is lacking. To complement the competencies found in the literature with insights from practice, we conducted 18 semi-structured interviews with design professionals. Our study identifies seven circular economy competencies for design: (1) Circular Impact Assessment, (2) Design for Recovery, (3) Design for Multiple Use Cycles, (4) Circular Business Models, (5) Circular User Engagement, (6) Circular Economy Collaboration, and (7) Circular Economy Communication. We used a general sustainability competencies framework to categorize our findings. Interestingly, we did not find evidence of the Systems Thinking competency in practice, although in the literature it is mentioned as a relevant competency for design for a circular economy. In addition, we found that methods and tools are still largely lacking or in a premature stage of development. We conclude that design for a circular economy can be seen as an upcoming, independent field within the sustainability domain, and that requires a specific set of competencies, methods, and tools. Our overview of circular economy competencies for design can guide the development of relevant methods and tools, circular economy-based design curricula, and training programs in the future.","design education; competencies; circular economy; product design; sustainability; circular consumption","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:1874e76e-39a0-41cf-9a4c-7eea8411b24f","http://resolver.tudelft.nl/uuid:1874e76e-39a0-41cf-9a4c-7eea8411b24f","Reprintable paste-based materials for additive manufacturing in a circular economy","Sauerwein, M. (TU Delft Circular Product Design); Zlopasa, J. (TU Delft BT/Environmental Biotechnology); Doubrovski, E.L. (TU Delft Mechatronic Design); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","","2020","The circular economy requires high-value material recovery to enable multiple product lifecycles. This implies the need for additive manufacturing to focus on the development and use of low-impact materials that, after product use, can be reconstituted to their original properties in terms of printability and functionality. We therefore investigated reprintable materials, made from bio-based resources. In order to equally consider material properties and recovery during development, we took a design approach to material development. In this way, the full material and product life cycle was studied, including multiple recovery steps. We applied this method to the development of a reprintable bio-based composite material for extrusion paste printing. This material is derived from natural and abundant resources, i.e., ground mussel shells and alginate. the alginate in the printing paste is ionically cross-linked after printing to create a water-resistant material. This reaction can be reversed to retain a printable paste. We studied paste composition, printability and material properties and 3D printed a design prototype. Alginate as a binder shows good printing and reprinting behaviour, as well as promising material properties. It thus demonstrates the concept of reprintable materials.","Additive manufacturing; Bio-based resources; Circular economy; Material integrity; Product design; Recycling","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:8ac4d926-2a92-428b-8490-2f27e5289381","http://resolver.tudelft.nl/uuid:8ac4d926-2a92-428b-8490-2f27e5289381","Reliability implications of partial shading on CIGS photovoltaic devices: A literature review","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices; TNO); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; TNO); Theelen, Mirjam (TNO)","","2019","Partial shading of Cu(In,Ga)(Se,S)2 (CIGS) photovoltaic (PV) modules is getting more attention, as is witnessed by the increase in publications on this topic in recent years. This review will give an overview of shading tests executed on CIGS modules and focuses on the more fundamental aspects that are often studied on cells. Generally, CIGS modules display very attractive performance under predictable row-to-row shading. However, potential damage could occur under nonoptimal shading orientations: module output after shading tests could reduce due to the formation of local shunts, often called wormlike defects. The influence of many factors on the formation of these defects, including the internal currents and voltages and the shape and intensity of the shade, will be discussed. This review allows an increased insight in the degradation mechanisms caused by partial shading, which would ultimately lead to the introduction of more shade-tolerant CIGS PV products in the future.","energy generation; photovoltaic; thin film","en","review","","","","","","Accepted author manuscript","","2020-06-30","","","Photovoltaic Materials and Devices","","",""
"uuid:9974c10b-f25b-44c9-898d-fbc8f71b68a1","http://resolver.tudelft.nl/uuid:9974c10b-f25b-44c9-898d-fbc8f71b68a1","Pastas: Open Source Software for the Analysis of Groundwater Time Series","Collenteur, R.A. (Institute of Earth Sciences); Bakker, M. (TU Delft Water Resources); Caljé, Ruben (Artesia Water); Klop, Stijn A. (Witteveen+Bos; Student TU Delft); Schaars, Frans (Artesia Water)","","2019","Time series analysis is an increasingly popular method to analyze heads measured in an observation well. Common applications include the quantification of the effect of different stresses (rainfall, pumping, etc.), and the detection of trends and outliers. Pastas is a new and open source Python package for the analysis of hydrogeological time series. The objective of Pastas is twofold: to provide a scientific framework to develop and test new methods, and to provide a reliable ready-to-use software tool for groundwater practitioners. Transfer function noise modeling is applied using predefined response functions. For example, the head response to rainfall is simulated through the convolution of measured rainfall with a Gamma response function. Pastas models are created and analyzed through scripts, ensuring reproducibility and providing a transparent report of the entire modeling process. A Pastas model can be constructed in seven simple steps: import Pastas, read the time series, create a model, specify the stresses and the types of response functions, estimate the model parameters, visualize output, and analyze the results. These seven steps, including the corresponding Python code, are applied to investigate how rainfall and reference evaporation can explain measured heads in an observation well in Kingstown, Rhode Island, USA. The second example demonstrates the use of scripts to analyze a large number of observation wells in batch to estimate the extent of the drawdown caused by a well field in the Netherlands. Pastas is free and open source software available under the MIT-license at http://github.com/pastas/pastas.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:c7700681-bfdf-4c2d-9580-0a190bf49dc2","http://resolver.tudelft.nl/uuid:c7700681-bfdf-4c2d-9580-0a190bf49dc2","Identification and Explanation of a Change in the Groundwater Regime using Time Series Analysis","Obergfell, C.C.A. (TU Delft Water Resources); Bakker, M. (TU Delft Water Resources); Maas, C. (Maas Geohydrologisch Advies)","","2019","Time series analysis is applied to identify and analyze a transition in the groundwater regime in the aquifer below the sand ridge of Salland in the Netherlands, where groundwater regime refers to the range of head variations throughout the seasons. Standard time series analysis revealed a discrepancy between modeled and observed heads in several piezometers indicating a possible change in the groundwater regime. A new time series modeling approach is developed to simulate the transition from the initial regime to the altered regime. The transition is modeled as a weighted sum of two responses, one representing the initial state of the system, the other representing the altered state. The inferred timing and magnitude of the change provided strong evidence that the transition was the result of significant dredging works that increased the river bed conductance of the main river draining the aquifer. The plausibility of this explanation is corroborated by an analytical model. This case study and the developed approach to identify a change in the groundwater regime are meant to stimulate a more systematic application of time series analysis to detect and understand changes in groundwater systems which may easily go unnoticed in groundwater flow modeling.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:bf4e0270-8fee-42bc-abb6-586e603054a6","http://resolver.tudelft.nl/uuid:bf4e0270-8fee-42bc-abb6-586e603054a6","Porosity controls the fracturing mode in rocks in unconfined compressive strength tests","Barnhoorn, A. (TU Delft Applied Geophysics and Petrophysics); Bakker, R.R. (TU Delft Reservoir Engineering); Douma, L.A.N.R. (TU Delft Applied Geophysics and Petrophysics); Pluymakers, Anne (TU Delft Applied Geophysics and Petrophysics); Bertotti, G. (TU Delft Applied Geology)","","2019","","","en","poster","","","","","","","","","","","Applied Geophysics and Petrophysics","","",""
"uuid:d84e13cb-f0e2-44a0-a3a6-1e14901d3c18","http://resolver.tudelft.nl/uuid:d84e13cb-f0e2-44a0-a3a6-1e14901d3c18","Analytic Solutions for Tidal Propagation in Multilayer Coastal Aquifers","Bakker, M. (TU Delft Water Resources)","","2019","A new analytic solution is presented for tidal propagation in multilayer coastal aquifers consisting of an arbitrary number of layers. The solution is derived using matrix calculus and may be applied to simulate tidal propagation in systems where aquifer layers are separated by leaky layers of low permeability or in stratified aquifers. The head, amplitude, and phase shift may be simulated for arbitrary tidal components. The transmissivity, storage coefficient, and loading efficiency may be different for every aquifer layer. Similarly, the resistance to vertical flow, storage coefficient, and loading efficiency may be different for every leaky layer. The aquifer system extends an infinite distance below the sea or may end abruptly at the shore line. In the former case, different aquifer and leaky layer properties may be specified below the sea and below the land. A homogeneous unconfined aquifer is simulated with 80 layers to demonstrate that the tidal signal propagates much farther inland in the deeper part than in the shallower part of an unconfined aquifer. This effect is enhanced significantly when layers of low permeability are present in the aquifer, even when these layers are fairly thin, such as clay lenses. The solution is implemented in Python and may be used, for example, to estimate aquifer parameters from head measurements in coastal aquifers.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:ef3ea91b-e4b2-46c6-8205-980c95aad1f9","http://resolver.tudelft.nl/uuid:ef3ea91b-e4b2-46c6-8205-980c95aad1f9","Co-creating circular product-service systems for long-lasting washing machines","van Dam, S.S. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design); Hazenoot, Thomas (Student TU Delft); Mihelič, Aleš (Gorenje d.d. Velenje)","Nissen, Nils F. (editor); Jaeger-Erben, Melanie (editor)","2019","This paper presents the result of a co-creation and context mapping study amongst seventeen washing machines users. The users had widely varying experiences with products offered through alternative ownership models, including three who were active users of a washing machine with pay-per-use or monthly subscription model. Through the co-creation process, user’s needs, concerns and desires were identified and translated into potential opportunities and barriers concerning the acceptance of circular product-service-systems for washing machines. The paper details the method used in the co-creation process and consecutively highlights six key benefits of using co-creation in the development of circular product-service systems and exemplify them with citations from users. Examples of these benefits are the added value that the product-service systems can give over classic ownership models, the value propositions that can form an entry point for users to be interested in the service, as well as how pricing and feedback schemes could accommodate different users and their needs and desires. In closing, the paper addresses the implications of these benefits, relate them to past literature, but also raise a number of questions and considerations in the application of co-creation for the development of circular product-service propositions.","co-creation; product-service systems; circular product design; washing machines; circular economy","en","conference paper","","","","","","","","","","","Circular Product Design","","",""
"uuid:6c7fb1f6-f472-4923-99f1-3ec81a00daec","http://resolver.tudelft.nl/uuid:6c7fb1f6-f472-4923-99f1-3ec81a00daec","Experimental investigation of the wave-induced motion of and force distribution along a flexible stem","Jacobsen, Niels G. (Deltares); Bakker, Wout (Deltares; EcoFlows); Uijttewaal, W.S.J. (TU Delft Environmental Fluid Mechanics); Uittenbogaard, Rob (Deltares)","","2019","The work presents an experimental investigation into the motion of and hydrodynamic forces along a single flexible stem in regular waves. The experiment covers a large range in relevant non-dimensional parameters: the drag-to-stiffness ratio, the inertia-to-stiffness ratio, the Keulegan-Carpenter number and the Reynolds number. The two first parameters relate to the response of the stem in waves and thus account for material properties, while the two last parameters are relevant for hydrodynamic forces on the stem. The displacement of the stem was captured with a digital video camera and the displacement along the stem was captured for every 2.5 mm at 25 Hz. This unique laboratory data set allowed for the following analyses: (i) Determination of the relevant non-dimensional parameter to predict the stem motion and shape. (ii) A direct comparison between the measured force for mimics of two lengths (0.15 m and 0.30 m) illustrating the force reduction potential for flexible mimics. (iii) Direct evaluation of the average force coefficients (drag) and (inertia) for the flexible stems. (iv) The distributed external hydrodynamic loading and the internal shear forces were estimated from the laboratory experiments. The distribution of the shear force helped to understand the breakage mechanisms of flexible stems. (v) A linkage between phase lags and internal shear forces was suggested. The data set is considered valuable as validation material for numerical models of stem motion in waves.","coastal engineering; wave-structure interactions","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2020-04-18","","","Environmental Fluid Mechanics","","",""
"uuid:4ed90b9a-3b30-46f1-b18d-b06f3d400114","http://resolver.tudelft.nl/uuid:4ed90b9a-3b30-46f1-b18d-b06f3d400114","De terp van Hogebeintum in boorkernen","Nicolay, Johan (Rijksuniversiteit Groningen; Terpencentrum); de Langen, Gilles (Terpencentrum; Provincie Fryslân; Rijksuniversiteit Groningen); Stöver, Jos (Cultural Heritage Agency of the Netherlands); Aalbersberg, Gerard (Terpencentrum; Agea-advies; Salisbury Archeologie B.V.; Rijksuniversiteit Groningen); Bahlen, Gregory (Student TU Delft); Bakker, Marco (Terpencentrum; Rijksuniversiteit Groningen); Huisman, Hans (Cultural Heritage Agency of the Netherlands); Mantel, Stephan (ISRIC World Soil Information); Ngan-Tillard, D.J.M. (TU Delft Geo-engineering)","Nieuwhof, Annet (editor); Knol, Egge (editor); Nicolay, Johan (editor)","2019","","","en","book chapter","Vereniging voor Terpenonderzoek","","","","","","","","","","Geo-engineering","","",""
"uuid:4c86283f-31f9-4d9b-a331-9417ed3f6201","http://resolver.tudelft.nl/uuid:4c86283f-31f9-4d9b-a331-9417ed3f6201","Estimation of Average Diffuse Aquifer Recharge Using Time Series Modeling of Groundwater Heads","Obergfell, C.C.A. (TU Delft Water Resources); Bakker, M. (TU Delft Water Resources); Maas, C. (Maas Geohydrologisch Advies)","","2019","A new method is presented to estimate average diffuse aquifer recharge of water table aquifers in temperate climates using time series analysis of water table level fluctuations. An accurate estimate of the recharge caused by rainfall requires an accurate estimate of the influence of evaporation. In temperate climates, evaporation imprints a seasonal component in the water table fluctuations. As such, recharge is estimated from time series models fitted to observed heads under the additional constraint that the seasonal harmonic of the observed head is reproduced as the sum of the transformed seasonal harmonics present in precipitation, evaporation, and pumping. An explicit equation is presented, in terms of the model parameters, for the damping and phase shift of the response to the seasonal harmonic of the stresses. Taking into account the seasonal harmonic of the observed heads results in more reliable recharge estimates compared to standard time series analysis. The method is limited to systems that are sufficiently linear and that remain unaltered over the analysis period. Head fluctuations and stresses should contain a seasonal harmonic that can be estimated with accurately. Runoff must be negligible or quantifiable. The method is applied to measured heads obtained from piezometers situated on and around the ice-pushed sand ridge of Salland in the Netherlands and compares well with recharge estimates based on the saturated zone chloride mass balance.","aquifer recharge; models reliability; time series analysis","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:e781d954-c3ba-4a7a-800a-154c41ee6b2d","http://resolver.tudelft.nl/uuid:e781d954-c3ba-4a7a-800a-154c41ee6b2d","Solving Groundwater Flow Problems with Time Series Analysis: You May Not Even Need Another Model","Bakker, M. (TU Delft Water Resources); Schaars, Frans (Artesia Water)","","2019","Time series analysis is a data-driven approach to analyze time series of heads measured in an observation well. Time series models are commonly much simpler and give much better fits than regular groundwater models. Time series analysis with response functions gives insight into why heads vary, while such insight is difficult to gain with black box models out of the artificial intelligence world. An important application is to quantify the contributions to the head variation of different stresses on the aquifer, such as rainfall and evaporation, pumping, and surface water levels. Time series analysis may be applied to answer many groundwater questions without the need for a regular groundwater model, such as what is the drawdown caused by a pumping station? Or, how long will it take before groundwater levels recover after a period of drought? Even when a regular groundwater model is needed to solve a groundwater problem, time series analysis can be of great value. It can be used to clean up the data, identify the major stresses on the aquifer, determine the most important processes that affect flow in the aquifer, and give an indication of the fit that can be expected. In addition, it can be used to determine calibration targets for steady-state models, and it can provide several alternative calibration methods for transient models. In summary, the overarching message of this paper is that it would be wise to do time series analysis for any application that uses measured groundwater heads.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:695e8069-ce82-48f1-957c-f1b90e293e14","http://resolver.tudelft.nl/uuid:695e8069-ce82-48f1-957c-f1b90e293e14","Extending the View on Project Performance","Molaei, M. (TU Delft Integral Design & Management); Bosch-Rekveldt, M.G.C. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2019","The main aim of this study is to gain insights into project management professionals’ perception of how project success can be achieved. The Q-methodology was followed in this research. Based on an extensive literature review and validation through expert judgment, a framework consisting of 33 factors increasing the likelihood of success was developed. A total of 34 practitioners in three different sectors (real estate, urban development, and infrastructure) in the Netherlands were asked to rank the statements contributing to the success of their projects. Four different perspectives of how project success can be achieved were distinguished in this study: “seeking the best match”, “being adaptive and open”, “keeping the team focused”, and “preparing for opportunities”. The perception of different practitioners of how success can be obtained may stem from factors of project context rather than sector and complexity. This highlights further research opportunities in taking a contingent approach when investigating project performance. The study helps to grasp the subjectivity of practitioners’ viewpoints regarding the potential ways to enhance project performance by understanding the similarity and differences of these viewpoints.","project management; project success factors; project performance criteria; project context; Q sorting","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:0d180996-6dda-4c6d-a709-99cbf4490eee","http://resolver.tudelft.nl/uuid:0d180996-6dda-4c6d-a709-99cbf4490eee","4TU.Bouw lighthouse projects + pdeng","Bakker, S.; van der Hoeven, F.D. (TU Delft 100% Research; TU Delft Urban Design)","","2019","","","en","contribution to periodical","","","","","","","","","","","100% Research","","",""
"uuid:8f2f42cc-f3be-4095-886e-889bcb87b473","http://resolver.tudelft.nl/uuid:8f2f42cc-f3be-4095-886e-889bcb87b473","Mediating between human driver and automation: state-of-the artand knowledge gaps : D1.1 of the H2020 project MEDIATOR","Christoph, M. (SWOV Institute for Road Safety Research); Cleij, D (SWOV Institute for Road Safety Research); Ahlström, H (SWOV Institute for Road Safety Research); Bakker, B. (Cygnify BV); Beggiato, M. (Chemnitz University of Technology); Borowsky, A. (Chemnitz University of Technology); van Egmond, R. (TU Delft Human Information Communication Design); van Grondelle, E.D. (TU Delft Design Aesthetics); de Ridder, H. (TU Delft Human Information Communication Design)","","2019","","","en","report","Mediator Consortium","","","","","","","","","","Human Information Communication Design","","",""
"uuid:0252d545-4c32-4cb3-af15-827770541dfc","http://resolver.tudelft.nl/uuid:0252d545-4c32-4cb3-af15-827770541dfc","Estimation of the Variation in Specific Discharge Over Large Depth Using Distributed Temperature Sensing (DTS) Measurements of the Heat Pulse Response","des Tombe, B.F. (TU Delft Water Resources); Bakker, M. (TU Delft Water Resources); Smits, F.J.C. (TU Delft Water Resources; Waternet); Schaars, Frans (Artesia); van der Made, Kees Jan (Wiertsema & Partners)","","2019","An approach is presented to determine groundwater flow in unconsolidated aquifers with a heat pulse response test using a heating cable and a fiber-optic cable. The cables are installed together using direct push so that the cables are in direct contact with the aquifer. The temperature response is measured for multiple days along the fiber-optic cable with Distributed Temperature Sensing (DTS). The new approach fits a two-dimensional analytical solution to the temperature measurements, so that the specific discharge can be estimated without knowledge of the position of the fiber-optic cable relative to the heating cable. Two case studies are presented. The first case study is at a managed aquifer recharge system where fiber-optic cables are inserted 15 m deep at various locations to test the fitting procedure. Similar and relatively large specific discharges are found at the different locations with little vertical variation (0.4–0.6 m/day). The second case study is at a polder, where the water level is maintained 2 m below the surrounding lakes, resulting in significant groundwater flow. The heating and fiber-optic cables are inserted to a depth of 45 m. The specific discharge varies 0.07–0.1 m/day and is significantly larger in a thin layer at 30-m depth. It is shown with numerical experiments that the estimated specific discharge is smoother than in reality due to vertical conduction, but the peak specific discharge is estimated correctly for layers thicker than ∼1.5 m.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:3a9494eb-52e2-4691-977f-4f14b6acd0e7","http://resolver.tudelft.nl/uuid:3a9494eb-52e2-4691-977f-4f14b6acd0e7","Predictive Mechanical model for fracture stimulation in an enhanced geothermal system (EGS) context","Lepillier, B.P. (TU Delft Reservoir Engineering); Bruhn, D.F. (TU Delft Reservoir Engineering); Daniilidis, Alexandros (TU Delft Reservoir Engineering); Bruna, P.B.R. (TU Delft Applied Geology); Bakker, R.R. (TU Delft Reservoir Engineering); Bastesen, Eivind (NORCE Norwegian Research Centre AS); Wheeler, Walter (NORCE Norwegian Research Centre AS); Torabi, Anita (NORCE Norwegian Research Centre AS); Garcia, Oscar (Instituto Politécnico Nacional ESIA Ticoman)","","2019","","","en","poster","","","","","","","","","","","Reservoir Engineering","","",""
"uuid:64a13fd4-edfe-4610-b20f-491278908281","http://resolver.tudelft.nl/uuid:64a13fd4-edfe-4610-b20f-491278908281","Challenges in Advanced Solid Waste Separation","Bakker, M.C.M. (TU Delft Resources & Recycling)","Offerman, Erik (editor)","2019","Efficient mechanical and sensor-based separation of mixed solid waste into valuable secondary materials is a critical step in recycling and in the preservation of primary resources. To position the associated research field, we discuss backgrounds and links to societal and political developments within and outside the classical waste chain. An encompassing theory detailing separation processes is briefly introduced and explained using appealing examples. The roles of science and industry in the development of innovative technologies is clarified, finishing with examples of physical principles that are behind many contemporary separation technologies. Throughout, scientific challenges and technological advances are identified.","","en","book chapter","World Scientific","","","","","","","","","","Resources & Recycling","","",""
"uuid:79d68757-1962-4b0a-97ee-3193e1120cf5","http://resolver.tudelft.nl/uuid:79d68757-1962-4b0a-97ee-3193e1120cf5","Material Property Changes in Defects Caused by Reverse Bias Exposure of CIGS Solar Cells","Bakker, N.J. (TU Delft Photovoltaic Materials and Devices; ECN part of TNO); Åhman, Hanna Nilsson (ECN part of TNO); Aantjes, Kees (ECN part of TNO); Barreau, Nicolas (Université de Nantes); Weeber, A.W. (TU Delft Photovoltaic Materials and Devices; ECN part of TNO); Theelen, Mirjam (ECN part of TNO)","","2019","Partial shading of Cu(In,Ga)Se2 modules can lead to the formation of reverse bias induced wormlike defects. These wormlike defects act as local shunts and permanently decrease module output. A good understanding of the formation and propagation mechanisms of these defects is needed in order to mitigate the negative effects, or to prevent these defects from forming. In this article, wormlike defects were formed on small nonencapsulated cells by exposing them to reverse bias conditions. Scanning electron microscopy-energy-dispersive X-ray spectroscopy measurements showed a rearrangement of elements: Indium, gallium, and copper were replaced by cadmium, whereas selenium was replaced by sulfur in the area around the defect. Moreover, additional electronic-defect levels were found in that area with spectrally resolved photoluminescence spectroscopy. Based on the material changes in the area close to the wormlike defects, a propagation mechanism is proposed. The model assumes a chemical reaction as the driving force for propagation instead of melting because of ohmic heating.","Cadmium; electric breakdown; photolumine-scence (PL); photovoltaic (PV) cells; reliability; thin film devices","en","journal article","","","","","","Accepted author manuscript","","","","","Photovoltaic Materials and Devices","","",""
"uuid:a1770a99-2bda-42db-a799-0c3dd3684a38","http://resolver.tudelft.nl/uuid:a1770a99-2bda-42db-a799-0c3dd3684a38","A Ten-Qubit Solid-State Spin Register with Quantum Memory up to One Minute","Bradley, C.E. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Randall, J.A.D. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Abobeih, M.H.M.A. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Berrevoets, R.C. (TU Delft QuTech Advanced Research Centre; TU Delft OLD SnC Sports; Kavli institute of nanoscience Delft); Degen, M.J. (TU Delft QID/Hanson Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Bakker, M. (TU Delft QN/Kavli Nanolab Delft; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Markham, M. (Element Six Innovation); Twitchen, D. J. (Element Six Innovation); Taminiau, T.H. (TU Delft QuTech Advanced Research Centre; TU Delft QID/Taminiau Lab; Kavli institute of nanoscience Delft)","","2019","Spins associated with single defects in solids provide promising qubits for quantum-information processing and quantum networks. Recent experiments have demonstrated long coherence times, high-fidelity operations, and long-range entanglement. However, control has so far been limited to a few qubits, with entangled states of three spins demonstrated. Realizing larger multiqubit registers is challenging due to the need for quantum gates that avoid cross talk and protect the coherence of the complete register. In this paper, we present novel decoherence-protected gates that combine dynamical decoupling of an electron spin with selective phase-controlled driving of nuclear spins. We use these gates to realize a ten-qubit quantum register consisting of the electron spin of a nitrogen-vacancy center and nine nuclear spins in diamond. We show that the register is fully connected by generating entanglement between all 45 possible qubit pairs and realize genuine multipartite entangled states with up to seven qubits. Finally, we investigate the register as a multiqubit memory. We demonstrate the protection of an arbitrary single-qubit state for over 75 s-the longest reported for a single solid-state qubit-and show that two-qubit entanglement can be preserved for over 10 s. Our results enable the control of large quantum registers with long coherence times and therefore open the door to advanced quantum algorithms and quantum networks with solid-state spin qubits.","","en","journal article","","","","","","","","","","","QID/Taminiau Lab","","",""
"uuid:615a98ec-c415-43e0-9519-78038af4b138","http://resolver.tudelft.nl/uuid:615a98ec-c415-43e0-9519-78038af4b138","Circular Product Design: Addressing Critical Materials through Design","Bakker, C.A. (TU Delft Circular Product Design); den Hollander, M.C. (TU Delft Circular Product Design); Peck, David (TU Delft Climate Design and Sustainability; TU Delft Beheer Grootschalige (EU) Projecten); Balkenende, R. (TU Delft Circular Product Design)","Offerman, Erik (editor)","2019","For product designers, the world has traditionally been one of resource
abundance. Introducing them to a resource-constrained world thus
requires new design strategies. This chapter explores how embedding
circular economy principles into design practice and education could
help product designers take critical material problems into account. We
introduce four product design strategies that address materials criticality:
(1) avoiding and (2) minimizing the use of critical materials, (3)
designing products for prolonged use and reuse, and (4) designing
products for recycling. The ‘circular’ strategies (3) and (4) are
elaborated, as these sit most firmly within the remit of product design.
This leads to a typology of circular product design that redefines product
and material lifetime in terms of obsolescence, and introduces a range of
approaches to resist, postpone or reverse product and material
obsolescence. The typology establishes the basis for the field of circular
product design, bringing together design approaches that were until this
date unconnected and paving the way for the development of detailed
design methods.","","en","book chapter","World Scientific","","","","","","","","","","Circular Product Design","","",""
"uuid:8b6b0e41-216d-4b69-9c9b-769aacea394b","http://resolver.tudelft.nl/uuid:8b6b0e41-216d-4b69-9c9b-769aacea394b","Design competencies for a circular economy","Sumter, Deborah (TU Delft Circular Product Design); de Koning, J.I.J.C. (TU Delft Design for Sustainability); Bakker, C.A. (TU Delft Circular Product Design); Balkenende, R. (TU Delft Circular Product Design)","Nissen, Nils F. (editor); Jaeger-Erben, Melanie (editor)","2019","Limited research has been done on design competencies for a circular economy in practice. Yet, an overview of design competencies for a circular economy would be useful to understand which topics should be emphasized in both education and practice. This paper focuses on deriving circular economy competencies for product designers working in industry. The study consisted of three focus groups with twelve designers that are actively exploring circular economy opportunities in an industrial product design context. We derived six design competencies for a circular economy: (1) circular economy understanding, (2) circular economy storytelling (3) setting circular criteria, (4) assessing circular solutions, (5) connecting reverse logistics with users, and (6) design for multiple use cycles. These six competencies are presented and reflected upon by comparing them to competencies found in literature. Two of the competencies found (i.e., circular economy understanding and storytelling) are new compared to those mentioned in literature. The other four competencies found in this study overlap or further specify competencies mentioned in literature. Ultimately, the relevancy of each of the six competencies for an individual designer is determined by the role this designer has in a company.","Circular economy; Product design; design competencies","en","conference paper","","","","","","","","","","","Circular Product Design","","",""
"uuid:eda9b0d3-c9c6-416a-81cb-e78a00e6e8d5","http://resolver.tudelft.nl/uuid:eda9b0d3-c9c6-416a-81cb-e78a00e6e8d5","An innovative route to circular rigid plastics","van Engelshoven, Y.D. (TU Delft Resources & Recycling); Wen, P. (TU Delft Resources & Recycling); Bakker, M.C.M. (TU Delft Resources & Recycling); Balkenende, R. (TU Delft Circular Product Design); Rem, P.C. (TU Delft Resources & Recycling)","","2019","An innovative route for plastics recycling is proposed, based on a combination of a logarithmic sorting process and colour plus high-resolution near-infrared (NIR) sensors. Although counterintuitive, it is shown that such a technology could sort clean flakes from rigid packaging waste into a very large number of different plastic grades with modest sorter capacity, provided that the chosen sensor is able to differentiate correctly between any two grades of plastics in the waste. Tests with high-resolution NIR on single pixels of transparent flakes from different types and brands of packaging show that this is indeed the case for a selection of 20 different packaging items bought from shops. Moreover, the results seem to indicate, in line with previous research, that high-resolution NIR data can be linked to important physical plastic properties like the melt flow viscosity and tensile strength. The attraction of deep sorting of waste plastics with relatively cheap sensors and modest sorter capacity is that the present industrial practice of tuning plastic grades to specific applications could coexist with commercial high-grade recycling at high levels of circularity and low carbon footprint. Therefore, advanced recycling technology is likely to be a societal alternative to phasing out plastics for rigid applications.","Circularity; NIR; Plastics; Recycling; Sensor sorting","en","journal article","","","","","","","","","","","Resources & Recycling","","",""
"uuid:aa28b912-e51e-4e74-97af-eec34adb3adb","http://resolver.tudelft.nl/uuid:aa28b912-e51e-4e74-97af-eec34adb3adb","How client attachment affects information verification in commercial valuation practice","Klamer, Pim (Hogeschool Utrecht; Universiteit Utrecht); Gruis, V.H. (TU Delft Management in the Built Environment); Bakker, Cok (Universiteit Utrecht)","","2019","Purpose: Information verification is an important factor in commercial valuation practice. Valuers use their professional autonomy to decide on the level of verification required, thereby creating an opportunity for client-related judgement bias in valuation. The purpose of this paper is to assess the manifestation of client attachment risks in information verification. Design/methodology/approach: A case-based questionnaire was used to retrieve data from 290 commercial valuation professionals in the Netherlands, providing a 15 per cent response rate of the Dutch commercial valuation population. Descriptive and inferential statistics have been used to test research hypotheses involving relations between information verification and professional features that may indicate client attachment such as an executive job level and brokerage experience. Findings: The results reveal that valuers acting at partner level within their organisation obtain lower scores on information verification compared to lower-ranked valuers. Also, brokerage experience correlates negatively to information verification of valuation professionals. Both findings have statistical significance. Research limitations/implications: The results reflect valuers’ reasoning behaviour rather than actual behaviour. Replication of findings through experimental design will contribute to research validity. Practical implications: Maintaining close client contact in a competitive environment is important for business continuity yet may foster client attachment. The associated downside risks in valuation practice call for higher awareness of (subconscious) client influence and the development of attitudinal scepticism in valuer training programmes. Originality/value: This paper is one of the few that explore possible sources of valuer judgement bias by relating client-friendly valuer features to a key area of valuation i.e. information verification.","Job level; Judgement bias; The Netherlands","en","journal article","","","","","","","","","","Management in the Built Environment","","","",""
"uuid:5316e3ae-1e43-42ef-973c-a462c3f5a078","http://resolver.tudelft.nl/uuid:5316e3ae-1e43-42ef-973c-a462c3f5a078","Spatial analysis of new testament textual emendations utilizing confusion distances","van Altena, V.P. (TU Delft Urban Data Science; Vrije Universiteit Amsterdam); Krans, Jan (Vrije Universiteit Amsterdam); Bakker, Henk (Vrije Universiteit Amsterdam); Dukai, B. (TU Delft Urban Data Science); Stoter, J.E. (TU Delft Urban Data Science)","","2019","Before the interpretation of any text can start, the original wording of the text itself must be critically established. Conventionally, this is done following qualitative criteria. This article, however, explores the application of spatial analyses to New Testament textual criticism by demonstrating how the Levenshtein edit distance could be adapted to calculate confusion distances for variant readings in New Testament manuscripts, i.e. the possibility that a (combination of) letter(s) is confused by another (combination of) letter(s). Subsequently the outcomes are translated to Euclidian space using classical Multi-Dimensional Scaling, which enables visualisation and spatial analyses (in this case not related to geographical space). The article focuses on the data preparation and algorithm to make the data suitable for spatial analyses, thus providing the New Testament textual critic with new analytical tools.","conjectural criticism; distant metrics; spatial analysis; spatialization; textual criticism","en","journal article","","","","","","","","","","","Urban Data Science","","",""
"uuid:f3e3036b-f381-4180-9c27-7cf18a122dd0","http://resolver.tudelft.nl/uuid:f3e3036b-f381-4180-9c27-7cf18a122dd0","Multiscale evaluation of potential damage in jetted lateral boreholes","Bakker, R.R. (TU Delft Reservoir Engineering); Barnhoorn, A. (TU Delft Applied Geophysics and Petrophysics)","","2019","We study the potential formation damage effects due to radial jet drilling on Bentheim sandstone, a homogeneous sandstone that is well established in terms of mechanical properties and widely used as reservoir analogue. We quantify how properties degrade with distance from a jetted hole on μm scale (porosity) and cm scale (compressive, tensile and acoustical properties). Moreover, we perform true-triaxial compression tests on samples with and without a jetted hole. It is concluded that, for this material, jetting has no direct influence on the surrounding area. No significant changes compared to intact material is found, nor can a significant change be detected with respect to distance to a jetted hole. Differences fall within the intra-block variability, and differences between blocks can be well explained by block-to-block variation. Differences in results of the true-triaxial compression tests can be attributed to a different sample geometry, which is corroborated by a numerical simulation. We conclude that the stress field around the jetted hole can therefore be well approximated by the Kirsch equations, modified for compression, and thereby accurately describe the stability of the lateral borehole.","CT scan analysis; Jet drilling; Lateral damage; Sample variability; True-triaxial testing; UCS testing","en","journal article","","","","","","","","","","","Reservoir Engineering","","",""
"uuid:bef38a93-dff2-4b5b-82e8-61ff8cfde968","http://resolver.tudelft.nl/uuid:bef38a93-dff2-4b5b-82e8-61ff8cfde968","Exploring the potential of additive manufacturing for product design in a circular economy","Sauerwein, M. (TU Delft Circular Product Design); Doubrovski, E.L. (TU Delft Mechatronic Design); Balkenende, R. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design)","","2019","Additive manufacturing, also known as 3D printing, is acknowledged for its potential to support sustainable design. In this paper, we explore whether the opportunities that additive manufacturing offers for sustainable design are also useful when designing for a circular economy, and to what extent additive manufacturing can support design for a circular economy. We performed a literature review on the sustainability aspects of additive manufacturing and held a series of interviews with designers about their 3D printed design projects to obtain in-depth information. The interviews were analysed using annotated portfolios, a novel analysis method created specifically for this research. This resulted in a visual representation of the outcomes. We found that additive manufacturing supports circular design strategies by creating opportunities to extend a product's lifespan, for instance by enabling repair or upgrades, even if these products were not originally designed for ease of repair or upgrading. However, the use of monolithic structurally complex parts that support design for recyclability may hinder high value product recovery, like repair. Besides this, the current offer of 3D printable materials should be extended with materials developed for durable use, as well as high-value reuse. Concluding, when accounting for these drawbacks, additive manufacturing is able to support multiple product life cycles and can provide valuable contributions to a circular economy.","additive manufacturing; Annotated portfolios; Circular economy; Design for sustainability; Product design; Product life extension","en","journal article","","","","","","Accepted author manuscript","","2021-04-30","","","Circular Product Design","","",""
"uuid:0fab3987-60fa-4737-8e85-b955f5f02d0c","http://resolver.tudelft.nl/uuid:0fab3987-60fa-4737-8e85-b955f5f02d0c","One-second coherence for a single electron spin coupled to a multi-qubit nuclear-spin environment","Abobeih, M.H.M.A. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Cramer, J. (TU Delft ALG/General; TU Delft QID/Hanson Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Bakker, M.V. (TU Delft Aerospace Engineering; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Kalb, N. (TU Delft QID/Hanson Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft); Markham, M. (Element Six Innovation); Twitchen, D. J. (Element Six Innovation); Taminiau, T.H. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft)","","2018","Single electron spins coupled to multiple nuclear spins provide promising multi-qubit registers for quantum sensing and quantum networks. The obtainable level of control is determined by how well the electron spin can be selectively coupled to, and decoupled from, the surrounding nuclear spins. Here we realize a coherence time exceeding a second for a single nitrogen-vacancy electron spin through decoupling sequences tailored to its microscopic nuclear-spin environment. First, we use the electron spin to probe the environment, which is accurately described by seven individual and six pairs of coupled carbon-13 spins. We develop initialization, control and readout of the carbon-13 pairs in order to directly reveal their atomic structure. We then exploit this knowledge to store quantum states in the electron spin for over a second by carefully avoiding unwanted interactions. These results provide a proof-of-principle for quantum sensing of complex multi-spin systems and an opportunity for multi-qubit quantum registers with long coherence times.","","en","journal article","","","","","","","","","Aerospace Engineering","","QID/Taminiau Lab","","",""
"uuid:5b4cc7d7-084a-4803-a7b6-ce5376cdc1d8","http://resolver.tudelft.nl/uuid:5b4cc7d7-084a-4803-a7b6-ce5376cdc1d8","Estimating Travel Time in Bank Filtration Systems from a Numerical Model Based on DTS Measurements","des Tombe, B.F. (TU Delft Water Resources); Bakker, M. (TU Delft Water Resources); Schaars, Frans (Artesia); van der Made, Kees Jan (Wiertsema & Partners)","","2018","An approach is presented to determine the seasonal variations in travel time in a bank filtration system using a passive heat tracer test. The temperature in the aquifer varies seasonally because of temperature variations of the infiltrating surface water and at the soil surface. Temperature was measured with distributed temperature sensing along fiber optic cables that were inserted vertically into the aquifer with direct push equipment. The approach was applied to a bank filtration system consisting of a sequence of alternating, elongated recharge basins and rows of recovery wells. A SEAWAT model was developed to simulate coupled flow and heat transport. The model of a two-dimensional vertical cross section is able to simulate the temperature of the water at the well and the measured vertical temperature profiles reasonably well. MODPATH was used to compute flowpaths and the travel time distribution. At the study site, temporal variation of the pumping discharge was the dominant factor influencing the travel time distribution. For an equivalent system with a constant pumping rate, variations in the travel time distribution are caused by variations in the temperature-dependent viscosity. As a result, travel times increase in the winter, when a larger fraction of the water travels through the warmer, lower part of the aquifer, and decrease in the summer, when the upper part of the aquifer is warmer.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:e1066c23-3bf1-440c-9575-8e939cb9319e","http://resolver.tudelft.nl/uuid:e1066c23-3bf1-440c-9575-8e939cb9319e","Explaining the development of use of public transport in the Netherlands from 2005-2016","van der Loop, Han (KiM: Kennisinstituut voor Mobiliteitsbeleid); Bakker, Peter (KiM: Kennisinstituut voor Mobiliteitsbeleid); Savelberg, Fons (KiM: Kennisinstituut voor Mobiliteitsbeleid); Kouwenhoven, M.L.A. (TU Delft Transport and Logistics; Significance); Helder, Eveline (Significance)","","2018","Objective
Until 2016, the KiM Netherlands Institute for Transport Policy Research annually explained the development of train passenger kilometres over the preceding ten years by using the national development of its drivers (such as population growth and train kilometers), as well as the elasticities of demand for those drivers. Since some years this method appeared to be less appropriate for completely explaining the increase in train patronage (+24% from 2005 to 2016). To acquire a complete as possible explanation of patronage development, KiM developed a more thorough method, using the Ministry of Infrastructure and Water Management’s National Model System (LMS), in cooperation with experts of public transport and of LMS. The LMS is a forecasting system for simulating developments in mobility, as based on a spatiotemporal detailed model of the drivers of mobility. The application of this forecasting system for an ex post evaluation can be regarded as innovative.
Method
The LMS generates OD matrices between origin and destination zones for car, public transport and bicycle (trips and kilometers) on an average working day. The output depends on a number of influencing factors such as population, employment, income, car ownership, road congestion, and the public transport service levels and pricing. To explain the development of public transport use from 2005 until 2016 models runs were made of 2004, 2010 and 2014, because much input data were already available for those years . To assess the impact of each influencing factor, we compared a model run with another model run in which only that particular influencing factor was changed, as based on the actual development, while all other factors remained constant. We extrapolated the results to the period 2005-2016, as based on empirical national data.
Results
Based on LMS-analyses, we concluded that the 24% increase in train patronage during the period 2005-2016 was mainly determined by population growth (+5%), train passenger kilometres by students travelling with a student pass card (+4%) and improvements in level of service (+10%). Improvements in level of service consisted of higher frequencies, new rail lines, and better connections between train services. The increase in jobs, income, air traffic, road congestion and fuel price appeared to have small effects. A decreasing impact on train passenger kilometers was caused by the increase of train fares (-5%). The LMS analyses left a growth of 8% unexplained. From other data and analyses it appeared that this 8% increase in train passenger kilometres can be the result of a larger impact from the amount of students (about +1%), improved punctuality (about +1%), and a considerably smaller impact of price changes than -5%, because not all discount offers can be regarded as included in the LMS analyses.
Conclusions
LMS analyses explained the development of train passenger kilometers 2005-2016 better than the previous method, which was based on national developments of influencing factors and elasticities. Cause of the unexplained differences between the monitored developments of public transport use and the explanations based on LMS analyses can be: an insufficient degree of detail of data on patronage and level of service of public transport available for research, as well as insufficient representations in LMS analyses of socioeconomic factors, of pricing and of level of service.
Product design is thought to play a crucial role in enabling this. Having a robust overview of relevant design roles and competencies is of foundational importance for the development of circular design tools and methods, and for the development of circular economy-based design curricula in higher education. However, how the role of design and the competencies required by designers need to change has hardly been investigated. Building on insights from literature regarding competencies of designers required to consider sustainability, sustainable design, and circular design, we developed a framework in which these competencies are related to the functional, coordinating, and strategic roles that have been recognized within the literature for designers. To complement the results from the literature with insights from practice, a single longitudinal in-depth case study was carried out describing a lease and refurbishment pilot conducted by a Dutch design-driven manufacturer of baby strollers. This case study allowed verification of the literature regarding the functional and coordinating roles of the designer. In addition, we were able to fill the gap observed in the literature regarding the strategic role product designers can assume when designing offers for circular business models. The competencies that we found are (1) the ability to concurrently develop the circular business model and the product’s design and (2) the ability to anticipate how the circular offering will evolve over multiple lifecycles. These findings have been used to expand the framework.","circular economy; product design; refurbishment; alternative ownership model; lease model; design competencies; OA-Fund TU Delft","en","journal article","","","","","","","","","","","Circular Product Design","","",""
"uuid:55b673ee-36de-4549-91e6-4f3002fd6f3f","http://resolver.tudelft.nl/uuid:55b673ee-36de-4549-91e6-4f3002fd6f3f","Lowering the Beneluxtunnel","Weeda, Tomas (Municipality of Amsterdam); de Gijt, J.G. (TU Delft Hydraulic Structures and Flood Risk; Gemeente Rotterdam); Bakker, K.J. (TU Delft Hydraulic Structures and Flood Risk); Braam, C.R. (TU Delft Concrete Structures); Broos, Eric (Gemeente Rotterdam); Jonkman, Sebastiaan N. (TU Delft Hydraulic Structures and Flood Risk)","Park, J.W. (editor); Ay Lie, H. (editor); Hardjasaputra, H. (editor); Thayaalan, P. (editor)","2017","As a result of the persistent increase of container vessel dimensions, future problems regarding navigation draught in the presence of tunnels are becoming more likely to occur. Hence, possible solutions to this problem have been investigated for the Beneluxtunnel. Several design options have been elaborated to determine the technical and economic feasibility of a possible lowering of the tunnel. Important subjects involved are the consequences of increasing the slopes, the cross-sectional concrete capacity, the use of joint rotations, the construction methods and the costs. This initial exploration of the subject shows lowering the Beneluxtunnel seems to be possible and is expected to be economically attractive. However, further research into certain boundary conditions and risky aspects of construction is required to ascertain this statement.","","en","conference paper","","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:0ea5bf4c-9a68-4491-9ea4-edf055799102","http://resolver.tudelft.nl/uuid:0ea5bf4c-9a68-4491-9ea4-edf055799102","Stability Analysis Quay Wall at the Amazonehaven, Port of Rotterdam","Mourillon, Nadevah K.N. (Gemeente Rotterdam); de Gijt, J.G. (TU Delft Hydraulic Structures and Flood Risk; Gemeente Rotterdam); Bakker, K.J. (WAD 43 Bv Consulting Engineers); Brassinga, Henk (Geotechnical consultant); Broos, E.J. (Port of Rotterdam)","Park, J.W. (editor); Ay Lie, H. (editor); Hardjasaputra, H. (editor); Thayaalan, P. (editor)","2017","The stability of any structure is an important aspect in civil engineering. This aspect is the subject of the researched quay wall at the Amazonehaven, port of Rotterdam. The quay wall with a relieving platform structure had in various section, over the entire 900m length of the quay, large deformations at the toe of the combined wall. The purpose was to analyse and quantify the influence of the deformed combined wall on the stability of the quay wall, its service lifetime. To obtain a better insight into the concept of stability, analytical methods based on the Blum theory, beam on elastic foundation method and finite element method using Plaxis 3D were applied and compared. The finite element method, Plaxis 3D, proved to be a better method to investigate the quay wall. Plaxis 3D takes into account the 3-dimensional effects of the quay wall and considers the actual soil behaviour during calculation which is a sophisticated manner of modelling a quay wall. A calibration model (which is the actual designed quay wall) and a series of models with various penetration depth of the combined wall are modelled. Also, a safety analysis of the soil parameters were applied to the various models.","","en","conference paper","","","","","","","","","","","Hydraulic Structures and Flood Risk","","",""
"uuid:84724e52-6462-46e2-9c5b-bdb7f1ce5ac8","http://resolver.tudelft.nl/uuid:84724e52-6462-46e2-9c5b-bdb7f1ce5ac8","Exploring the influence of external actors on the cooperation in public–private project organizations for constructing infrastructure","Koops, L.S.W. (TU Delft Integral Design & Management; Witteveen+Bos); Bosch-Rekveldt, M.G.C. (TU Delft Integral Design & Management); Bakker, H.L.M. (TU Delft Integral Design & Management); Hertogh, M.J.C.M. (TU Delft Integral Design & Management)","","2017","Though different forms of public–private partnerships exist, in the organizational structure of most forms a public and a private project organization can be derived, resulting in two collaborating project organizations. The literature on project management however mostly considers one project organization. The literature on public–private partnerships considers the public part of the organization mostly as ‘the client’. This research focuses on the relationships between public and private organizations: the two collaborating project organizations, the relationship with their parent organizations, and with external actors. Exploratory interviews in three cases uncovered five mechanisms leading to tensions between project partners: ambiguity, conflict of interest, triangular relationships, unclear purpose and organizational context.","Case study; Parent organization; Project organization; Public–private collaboration; Relationships; Social networks","en","journal article","","","","","","","","2020-03-07","","","Integral Design & Management","","",""
"uuid:211e9dc4-7332-426a-aa11-9f6749423c9b","http://resolver.tudelft.nl/uuid:211e9dc4-7332-426a-aa11-9f6749423c9b","The influence of the length of the calibration period and observation frequency on predictive uncertainty in time series modeling of groundwater dynamics","van der Spek, J.E. (TU Delft Water Resources); Bakker, M. (TU Delft Structural Integrity & Composites)","","2017","The influence of the length of the calibration period and observation frequency on the predictive uncertainty in time series modeling of groundwater dynamics is investigated. Studied series are from deltaic regions with predominantly shallow groundwater tables in a temperate maritime climate where heads vary due to precipitation and evaporation. Response times vary over a wide range from ∼60 to ∼1200 days. A Transfer Function-Noise model is calibrated with the Markov Chain Monte Carlo method to both synthetic series and measured series of heads. The model fit and uncertainty are evaluated for various calibration periods and observation frequencies. It is often assumed that the required length of the calibration period is related to the response time of the system. In this study, no strong relationship was observed. Results indicate, however, that the required length of the calibration period is related to the decay time of the noise. Furthermore, the length of the calibration period was much more important than the total number of observations. For the measured series, the credible intervals could commonly be reduced to ∼10% of the measured head range and the prediction intervals to ∼50% of the measured head range with calibration periods of 20 years with approximately two observations per month.","calibration period; observation frequency; time series analysis; uncertainty","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:8fafb5ad-f740-4080-bb8d-f3020d1391d1","http://resolver.tudelft.nl/uuid:8fafb5ad-f740-4080-bb8d-f3020d1391d1","ResCoM Design Methodology for Multiple Lifecycle Products","Bakker, C.A. (TU Delft Circular Product Design); van Dam, S.S. (TU Delft Circular Product Design); de Pauw, I.C. (TU Delft Circular Product Design; IDEAL & CO Explore); van der Grinten, B. (TU Delft Education and Student Affairs; IDEAL & CO Explore); Asif, Farazee (KTH Royal Institute of Technology)","","2017","By combining the lessons learned from the four ResCoM industrial cases, a generic methodology was developed for other companies that want to engage in the development of multiple-lifecycle products. This report describes a stepwise approach for developing such products. The approach includes a suite of design tools as well as a practical case study example to illustrate the implementation in practice.","Product design; Design methodology; Circular Economy","en","report","Delft University of Technology","","","","","Deliverable report of the ResCoM-project (Resource Constrained Manufacturing)","","","","","Circular Product Design","","",""
"uuid:14171c24-4acf-4598-9172-fa9be8dcf890","http://resolver.tudelft.nl/uuid:14171c24-4acf-4598-9172-fa9be8dcf890","Uncovering ecodesign dilemmas: A path to business model innovation","Prendeville, S.M. (TU Delft Circular Product Design; Loughborough University London); O'Connor, Frank (Ecodesign Centre); Bocken, N.M.P. (TU Delft Circular Product Design); Bakker, C.A. (TU Delft Circular Product Design)","","2017","The aim of this article is to explore how ecodesign dilemmas contribute to a firm's ecodesign evolution. The article achieves this through empirical research into a process of ecodesign decision-making in a single firm. The study spans a timeframe of nine years. The article describes how recognising and dealing with ecodesign dilemmas fuels cycles of learning, leading the firm towards business model innovation. The study classifies a unique set of ecodesign dilemmas: hierarchies; tensions; contradictions; and oversights. Through this classification, we show how firms need to adopt a unified approach combining operational (ecodesign principles approach), tactical (ecodesign management processes) and strategic actions (business model innovation), to systematically manage ecodesign dilemmas. To support this, the article presents a framework describing key actions for operational, tactical and strategic ecodesign decision-making and the types of ecodesign dilemmas typical to each approach. Through this study, we show that the business model is critical to inform effective ecodesign decision-making and illustrate how design can drive firms towards sustainable change, from the bottom up.","Ecodesign; Ecodesign Maturity; Dilemmas; Trade-Offs; Business model innovation","en","journal article","","","","","","Accepted author manuscript","","2019-01-10","","","Circular Product Design","","",""
"uuid:468c805e-3183-4740-b353-5e687d792497","http://resolver.tudelft.nl/uuid:468c805e-3183-4740-b353-5e687d792497","Fluid shear stress-induced TGF-β/ALK5 signaling in renal epithelial cells is modulated by MEK1/2","Kunnen, S.J. (Leiden University Medical Center); Leonhard, W.N. (Leiden University Medical Center); Semeins, C. (Universiteit van Amsterdam; Vrije Universiteit Amsterdam); Hawinkels, L.J.A.C. (Leiden University Medical Center); Poelma, C. (TU Delft Multi Phase Systems); ten Dijke, P. (Leiden University Medical Center); Bakker, A. (Universiteit van Amsterdam; Vrije Universiteit Amsterdam); Hierck, B.P. (Leiden University Medical Center); Peters, D.J.M. (Leiden University Medical Center)","","2017","Renal tubular epithelial cells are exposed to mechanical forces due to fluid flow shear stress within the lumen of the nephron. These cells respond by activation of mechano-sensors located at the plasma membrane or the primary cilium, having crucial roles in maintenance of cellular homeostasis and signaling. In this paper, we applied fluid shear stress to study TGF-β signaling in renal epithelial cells with and without expression of the Pkd1-gene, encoding a mechano-sensor mutated in polycystic kidney disease. TGF-β signaling modulates cell proliferation, differentiation, apoptosis, and fibrotic deposition, cellular programs that are altered in renal cystic epithelia. SMAD2/3-mediated signaling was activated by fluid flow, both in wild-type and Pkd1−/− cells. This was characterized by phosphorylation and nuclear accumulation of p-SMAD2/3, as well as altered expression of downstream target genes and epithelial-to-mesenchymal transition markers. This response was still present after cilia ablation. An inhibitor of upstream type-I-receptors, ALK4/ALK5/ALK7, as well as TGF-β-neutralizing antibodies effectively blocked SMAD2/3 activity. In contrast, an activin-ligand trap was ineffective, indicating that increased autocrine TGF-β signaling is involved. To study potential involvement of MAPK/ERK signaling, cells were treated with a MEK1/2 inhibitor. Surprisingly, fluid flow-induced expression of most SMAD2/3 targets was further enhanced upon MEK inhibition. We conclude that fluid shear stress induces autocrine TGF-β/ALK5-induced target gene expression in renal epithelial cells, which is partially restrained by MEK1/2-mediated signaling.","Fluid flow; Mechanotransduction; Cilia; SMAD2/3 signaling; ERK1/2; Pkd1−/−","en","journal article","","","","","","","","","","","Multi Phase Systems","","",""
"uuid:893ca019-04ef-458f-ac00-6d66ae9be3a0","http://resolver.tudelft.nl/uuid:893ca019-04ef-458f-ac00-6d66ae9be3a0","Immersed tunnel design in subarctic rivers","Bergsma, J.G. (Tunnel Engineering Consultants; Royal HaskoningDHV); Bakker, K.J. (TU Delft Hydraulic Structures and Flood Risk; WAD43 bv); 't Hart, CMP (Royal HaskoningDHV; Tunnel Engineering Consultants)","","2017","The demand for tunnels crossing waterways in urban areas is expanding into colder regions, with immersed tunnels an increasingly competitive alternative for waterway crossings. Recent examples of new immersed tunnels affected by cold weather include the Bjørvika, Söderstrum, and Marieholm tunnels in Norway and Sweden. This article aims to describe the practical and technical issues related to applying the immersed tunnel construction method to colder regions for them to stay competitive.
An initial distinction can be made between tunnels crossing large water bodies and tunnels crossing rivers based on the differences in their ice regimes. For example, one of the main ice related issues for immersed tunnels crossing seas and lakes is ice pile-up, which results in heavy loading of the approaches and mechanical scour of the seabed. This is an issue which is relatively well documented and has been taken into account in projects like the Øresund tunnel. The ice regime of a river is quite different, where issues for immersed tunnels have thus far gone undocumented. Subarctic issues typical in river ice regimes may include ice jams, anchor ice, surges, water level drops, and thermal expansion of ice, as well as unfavorable material behavior.
The case of British WWII Utility Furniture scheme is one where consumer products were designed and developed as a response to severe material shortages. This action is set in the context of wartime conditions where the products were designed, manufactured, used and often reused over a long lifetime, under very stringent governmental control.
The control came from the government ministries but was designed and manufactured by the private sector. The furniture scheme was brought in to allow workers to have a furnished home to live in, eat and rest to allow them to work to help win the war.
Drawing on policy lessons from the wartime cases this paper makes a comparison of the WWII British approach with a European 21st century action plan for the circular economy, which raises important questions for policy development.
The outcomes of the literature study reveal the aspects of the digital and additive characteristics of AM, that lead to potential sustainability opportunities. We compared these aspects to the circular design strategies as described by Bakker et al. (2014) and Bocken et al. (2016) in the context of the five selected design projects. Each project is described in terms of circular design strategies and how these were achieved through additive manufacturing.
Using design practice to reflect on the outcomes of the literature review resulted in a better understanding of the potential of additive manufacturing for circular product design. The relation between the sustainability aspects of AM and the circular design strategies were made explicit. AM seems to be especially suitable to customize parts to fit existing products and to contribute to new opportunities regarding material recycling. These findings deserve further exploration in order to understand the motives for implementation in circular product design.","Circular product design; Additive manufacturing; 3D printing; Circular economy; Sustainability","en","conference paper","IOS Press","","","","","","","","","","Circular Product Design","","",""
"uuid:840ef52a-ff92-44c7-ae7b-d37169389ebb","http://resolver.tudelft.nl/uuid:840ef52a-ff92-44c7-ae7b-d37169389ebb","HESS opinions: Repeatable research: What hydrologists can learn from the Duke cancer research scandal","Fienen, Michael N. (US Geological Survey Wisconsin Water Science Center); Bakker, M. (TU Delft Water Resources)","","2016","In the past decade, difficulties encountered in reproducing the results of a cancer study at Duke University resulted in a scandal and an investigation which concluded that tools used for data management, analysis, and modeling were inappropriate for the documentation of the study, let alone the reproduction of the results. New protocols were developed which require that data analysis and modeling be carried out with scripts that can be used to reproduce the results and are a record of all decisions and interpretations made during an analysis or a modeling effort. In the hydrological sciences, we face similar challenges and need to develop similar standards for transparency and repeatability of results. A promising route is to start making use of open-source languages (such as R and Python) to write scripts and to use collaborative coding environments (such as Git) to share our codes for inspection and use by the hydrological community. An important side-benefit to adopting such protocols is consistency and efficiency among collaborators.","","en","journal article","","","","","","","","","","","Water Resources","","",""
"uuid:8d913a1c-53f4-4e97-b6b7-fa7805b1481c","http://resolver.tudelft.nl/uuid:8d913a1c-53f4-4e97-b6b7-fa7805b1481c","A storm is coming? Collective sensemaking and ambiguity in an inter-organizational team managing railway system disruptions","Merkus, Sander (Vrije Universiteit Amsterdam); Willems, Thijs (Vrije Universiteit Amsterdam); Schipper, Danny (Erasmus Universiteit Rotterdam); van Marrewijk, Alfons (Vrije Universiteit Amsterdam); Koppenjan, Joop (Erasmus Universiteit Rotterdam); Veenswijk, Marcel (Vrije Universiteit Amsterdam); Bakker, H.L.M. (TU Delft Integral Design & Management)","","2016","This paper studies the ways in which members of inter-organizational teams collectively make sense of unexpected events and how they decide upon engaging in action. Frequently, ambiguity dominates such change processes aimed to create common understanding. Using the notion of the duality of intrinsic and constructed ambiguity, a detailed analysis of the collective sensemaking efforts of an inter-organizational team of railway coordinators in the Operational Control Center Rail was conducted. Building on team meetings observations during the days preceding a large and potentially disruptive winter storm in December 2013, the case study describes the process of collectively making sense of the disruptiveness of the storm. The findings show that contextual and temporal factors determine whether collective sensemaking unfolds as either a shared or a negotiated process.","ambiguity; change; Collective sensemaking; disruption; sense of urgency","en","journal article","","","","","","","","","","","Integral Design & Management","","",""
"uuid:09bf11f9-d0e1-4856-a63e-509db67748c7","http://resolver.tudelft.nl/uuid:09bf11f9-d0e1-4856-a63e-509db67748c7","Product design and business model strategies for a circular economy","Bocken, N.M.P. (TU Delft Design for Sustainability); de Pauw, I.C. (IDEAL & CO Explore); Bakker, C.A. (TU Delft Design for Sustainability); van der Grinten, B. (IDEAL & CO Explore)","","2016","The transition within business from a linear to a circular economy brings with it a range of practical challenges for companies. The following question is addressed: What are the product design and business model strategies for
companies that want to move to a circular economy model? This paper develops a framework of strategies to guide designers and business strategists in the move from a linear to a circular economy. Building on Stahel, the terminology
of slowing, closing, and narrowing resource loops is introduced. A list of product design strategies, business model strategies, and examples for key decision-makers in businesses is introduced, to facilitate the move to a circular economy. This framework also opens up a future research agenda for the circular economy.
Color preferences regarding different topics show different patterns and significant differences were found between gender, age, education and personality such as being technical, being emotional or being a team player. Also different colors were mentioned when asked for colors that stimulate to be quiet, energetic, able to focus or creative. Probably, due to unconsciousness of contexts, many people had no color preference, a result that in the literature seldom is mentioned.
Blue was the overall favourite color, however most males chose for blue (25 %) while most females had no color preference (18 %). Black was the overall favourite color for clothing, mainly chosen by females (40%), while males primarily chose blue (27%). For building interiors subjects preferred white.
For moods, subjects preferred white for being quiet or being able to focus, red for being energetic and had no color preference for being creative.
It is concluded that color preferences are dependent upon the topic, and personal characteristics. The findings are important for architects, interior designers, fashion designers and product designers to have a basic idea of preferred colors for different objects by different types of people.","color preference; personal characteristics; personality; mood","en","journal article","","","","","","Accepted Author Manuscript","","","","","Applied Ergonomics and Design","","",""
"uuid:ebd89fe0-f9de-44a7-ad7e-4a98ec295626","http://resolver.tudelft.nl/uuid:ebd89fe0-f9de-44a7-ad7e-4a98ec295626","Design of an environmentally interactive continuum manipulator","Bakker, D.L.; Matsuura, D. (Tokyo Institute of Technology); Takeda, Y (Tokyo Institute of Technology); Herder, J.L. (TU Delft Mechatronic Systems Design)","Chang, S.H. (editor)","2015","Continuum manipulators are high degree of freedom structures that can use their increased degrees of freedom to navigate through an environment with obstacles. This type of manipulator is underactuated, which make them promising for adapting to their environments. However, current research is mainly focused on accurate positioning and obstacle avoidance, while the advantages of underactuated systems remain unused. Therefore this paper proposes a new design and approach of a continuum manipulator, which can navigate through an environment with obstacles by passively shaping the manipulator along the obstacles. The proposed design consists of a sequence of crosslink segments, where steering is done by an antagonistic pair of tendons and forward movement is done by a single pushing force at the base of the manipulator. Analytical models and a prototype show that this manipulator has a highly increased range of motion per segment compared with similar systems. The results also show that the manipulator is able to reach a target in a multi-obstacle environment using a simple binary control system with low input forces.","Continuum manipulators; Environmental interaction; Underactuated mechanisms","en","conference paper","","","","","","","","","","","Mechatronic Systems Design","","",""
"uuid:c800cea5-499e-4fe8-9412-3885ac529695","http://resolver.tudelft.nl/uuid:c800cea5-499e-4fe8-9412-3885ac529695","Developments and challenges in design for sustainability of electronics","Balkenende, R. (TU Delft Circular Product Design; Philips Research); Bakker, C.A. (TU Delft Circular Product Design)","Curran, R. (editor); Wognum, N. (editor); Borsato, M. (editor); Stjepandić, J. (editor); Verhagen, W.J.C. (editor)","2015","Sustainability of electronic products until recently mainly focused on improving the energy efficiency. Recently, resource efficiency has become of growing importance. Due to the use of relatively small amounts of many valuable and scarce materials, often intimately mixed, the design of electronic products deserves specific attention. From a materials perspective measures are needed to improve on recyclability. In addition to the use of recyclable materials, the ability to break connections between materials that are not compatible in recycling processes is crucial. Environmentally and economically more interesting than recovery of materials is the reuse of components or products. To enable multiple product lifecycles, product design should also explicitly address maintenance, upgradeability, modularity and disassembly. Design guidelines will be presented and challenges with respect to impact assessment and business model development will be discussed.","Circular economy; Design tools; Electronic waste; Electronics; End-of-life treatment; Product design; Re-use; Recycling; Resource efficiency; Sustainability","en","conference paper","IOS Press","","","","","","","","","","Circular Product Design","","",""
"uuid:f4118184-766c-4047-83db-37f8fbf4fc57","http://resolver.tudelft.nl/uuid:f4118184-766c-4047-83db-37f8fbf4fc57","Uncovering the secrets of a productive environment, A journey through the impact of plants and colour","Bakker, I.C.","Vink, P. (promotor); Van der Voordt, D.J.M. (promotor)","2014","This PhD concerns the relationship between the physical environment and knowledge productivity. To create an optimal environment it is important to study the needs of knowledge workers in connection to the characteristics of the physical environment. Two components of the physical environment have been analysed: plants and colour. The effects of plants on productivity are studied by a critical assessment of the literature. The impact of colour has been studied by an extensive review of the literature and a comparison of human responses to a red and blue painted meeting room, in a real life setting. In addition, questionnaires have been disseminated to measure peoples’ colour preferences on different topics. The choice for plants and colour is based on personal interest and because it is relatively easy to add and change plants and colours in real life settings. In the reviews of the literature particular attention has been paid to the research methods applied by other researchers, in particular in the field of environmental psychology, in order to understand the mechanisms behind the interaction between people and their environment and how this interaction affects their productivity. Based on these insights, a new framework has been developed to measure the perception of the built environment. Chapter 2 discusses the relationship between productivity of the knowledge worker, his networks, and knowledge, in connection to the physical environment. To ensure that the knowledge worker will be both productive and happy, it is hypothesized that it is important that he can fulfil all his needs. The psychologists Ryan and Deci (2000, 2001) mention three psychological needs: competences, relatedness and autonomy. Pink (2010) added two other needs: purpose and mastery. In knowledge work a distinction can be made between four types of work moods that not only matches with insights of modern Western psychologists, but also with ancient Eastern wisdom: social observation, collectiveness, contemplation and awareness. It is concluded that four characteristics of the physical environment can contribute to knowledge productivity: structure, variety, psychological safety and identity. These four factors have been elaborated into practical guidelines how to support the energy and different moods of the knowledge worker. Chapter 3 presents a critical assessment on the effects of plants on productivity, based on an review of the literature. Next to effects on indoor air quality and relative air humidity, plants have in general a positive effect on productivity. The reactions of people can be physical/physiological, affective, or cognitive. Due to the huge variety in research methods and research settings, the research findings are not well comparable. For this reason, an overview of test aspects and a list of plant characteristics is presented that should be taken into account in conducting new research. In this thesis will be focused on the totality of the environment. After a review on a component that easily can be isolated, the next component is integrated in context and can only be approached in totality. Chapter 4 presents the real life test whether different coloured meeting rooms (red, blue and a reference room) had any effect on self-reported productivity. No significant effects were found in the responses to the questionnaires. It is assumed that the participants were fully occupied by the meetings so that they didn’t experience consciously the surrounding colours. A relatively large number of subjects responded that colour did not matter related to productivity (65%), collaboration (58 %) and wellbeing (33 %). Chapter 5 provides an overview of colour preferences of 1077 Dutch people who were asked to fill out a questionnaire. Gender, age and education and some personality characteristics were significantly related to colour preferences. The overall favourite colour was blue although differences exist between males and females: especially males prefer blue. The overall colour preference for clothing is black: females preferred this colour a bit more than males. The most preferred colour for the interior of buildings is white. Regarding states of mind most people prefer white to be quiet or being able to concentrate, and red to be energetic. Regarding being creative, they stated to have no colour preference. Remarkably most people choose for the physical environment the colour white (30 till 40%) and a substantial percentage (16 till 22%) stated to have no colour preference. Based on this analysis of colour preferences, people seem to be less interested in the application of particular colours in their environment. Chapter 6 presents an in-depth analysis of the experience of colour in order to shed more light on how colour affects people physiologically, affectively and cognitively. This analysis is based on theoretical knowledge found in the literature. This literature shows that scientists, philosophers, artists and architects are rather sceptical about the often rational and scientific approach to understand colour. Theoretically, twelve colour characteristics can be discerned how colour appears in nature which can be linked to the twelve senses that were mentioned by Rudolf Steiner and to twelve colour contrasts. Both in practice and science, the HSI values (hue, saturation and intensity) are used to define colour, which is limited to only three colour contrasts. It is concluded that in order to understand the experience of colour in its totality, all twelve colour contrasts should be taken into account that can be related to the twelve senses. Chapter 7 discusses possible pitfalls in conducting colour research by using questionnaires. By means of accurate observations during the colour test of Chapter 4 it turned out that the responses to the questionnaires could not always clearly be related to the research topics and did not always reflect the actual views of the subjects. For this reason additional personal interviews have been conducted with a number of subjects after the test. Contextual, personal and psychological factors showed to influence the responses of the subjects, including well-known phenomena such as the impact of personal interest, social desirability and cognitive dissonance reduction. Chapter 8 reflects on the often applied three dimensions arousal, pleasure and dominance, that were developed by Mehrabian and Russell (1974) to measure people’s environmental experiences and are still widely used in environmental psychology research. The many studies on people-environment interactions are hard to compare due to the different interpretations of these dimensions and the use of a huge variety of related adjectives. In this PhD research an attempt has been made to explore the connections between pleasure, arousal and dominance, the ABC model of attitude with the factors Affect, Behaviour and Cognition, and the three functions of the soul, feeling, acting and thinking, that were mentioned by Plato. It can be concluded that the dimensions of arousal, pleasure and dominance as Mehrabian and Russell originally have meant to be, are still appropriate to be used to describe peoples’ experience of the physical environment, provided that the dimensions are well defined and operationalised in valid adjectives. In particular the often neglected third dimension ‘dominance’ deserves a rehabilitation. Based on the discrepancies and the flaws that were found in research using pleasure, arousal and dominance to measure the experience and perceptual qualities of the built environment, chapter 9 presents a new framework with bipolar adjectives to describe the experience of the physical environment. This framework refers to the twelve senses that were mentioned by Rudolf Steiner. By linking sensory information of the twelve senses to specific parts of the environment, it is possible to define people’s experience of the physical environment in a more clear and objective way. The framework has been tested with practitioners from the field of housing and care and with designers. It showed to be applicable to get a sound understanding of the qualities of the physical environment, why people respond differently to the same environment, and how to improve this environment. Further testing of the framework with different samples and in different settings is needed to validate the framework. The thesis ends with chapter 10 that presents the overall conclusions and recommendations and reflects on the limitations of the research and next steps. This study tried to disentangle the complex concept productivity into four different work moods (contemplation, social observation, collectiveness, and awareness) and mentions four important elements of the physical environment: structure, variety, psychological safety and identity. The review on the effects of plants on productivity showed that plants in general have positive effects. Based on the research on colour, this relationship could not clearly be defined due to the complexity of both the concepts colour and productivity. However, the effects of colour on mood are definable. Because productivity can be conceived as a phenomenon existing of four types of work moods, future researchers can approach productivity more concrete. The developed framework to value and assess the totality of the environment can be helpful.","Physical environment; plants; colour; experience; senses","en","doctoral thesis","","","","","","","","","Industrial Design Engineering","Industrial Design","","","",""
"uuid:bc215c9d-f5d2-4d74-8c87-2473094e9d78","http://resolver.tudelft.nl/uuid:bc215c9d-f5d2-4d74-8c87-2473094e9d78","Quantification of the influence of preferential flow on slope stability using a numerical modeling approach (discussions)","Shao, W.; Bogaard, T.A.; Bakker, M.; Greco, R.","","2014","The effect of preferential flow on the stability of landslides is studied through numerical simulation of two types of rainfall events on a hypothetical hillslope. A model is developed that consists of two parts. The first part is a model for combined saturated/unsaturated subsurface flow and is used to compute the spatial and temporal water pressure response to rainfall. Preferential flow is simulated with a dual-permeability continuum model consisting of a matrix domain coupled to a preferential flow domain. The second part is a~soil mechanics model and is used to compute the spatial and temporal distribution of the local factor of safety based on the water pressure distribution computed with the subsurface flow model. Two types of rainfall events were considered: long duration, low-intensity rainfall, and short duration, high-intensity rainfall. The effect of preferential flow on slope stability is assessed through comparison of the failure area when subsurface flow is simulated with the dual-permeability model as compared to a single-permeability model (no preferential flow). For the low-intensity rainfall case, preferential flow has a positive effect on the slope stability as it drains the water from the matrix domain resulting in a smaller failure area. For the high-intensity rainfall case, preferential flow has a negative effect on the slope stability as the majority of rainfall infiltrates into the preferential flow domain when rainfall intensity exceeds the infiltration capacity of the matrix domain, resulting in larger water pressure and a larger failure area.","","en","journal article","European Geosciences Union","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:e2ea8361-29ab-44c7-b88e-0b380063f369","http://resolver.tudelft.nl/uuid:e2ea8361-29ab-44c7-b88e-0b380063f369","More disposable than ever? Consequences of non-removable batteries in mobile devices","Bakker, C.A.; Kuijer, L.","","2014","Mobile devices like smart phones, tablet computers and ultraportable laptops are experiencing rapid worldwide market growth and have relatively short lifespans. Recently, embedded (non-removable) batteries were introduced that cannot be replaced by consumers. This study traces the environmental and social consequences of the introduction of embedded batteries throughout the value chain: from the original equipment manufacturers, to the users of mobile devices, to the repair, refurbishment and end-of-life recycling companies. It shows that the introduction of embedded batteries was mainly technology and design-driven, that original owners are hardly aware of embedded batteries (unless they seek to prolong the life of their phones), that embedded batteries have contributed to a thriving but mostly unauthorized repair and refurbishment market and finally that recyclers have difficulties removing the batteries. From a social and environmental sustainability perspective, reintroducing removable batteries is preferable, but the study shows this may not be feasible and examines alternative options.","","en","conference paper","Austrian Society for Systems Engineering and Automation","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:3425f104-ab98-4d09-8888-14f5cffe67e3","http://resolver.tudelft.nl/uuid:3425f104-ab98-4d09-8888-14f5cffe67e3","Designer focused quickscan recyclability assessment method","Fakhredin, F.; Bakker, C.A.; Geraedts, J.M.P.","","2014","Recycling crosses the fields of resource engineering, metallurgy and materials sciences, and designers cannot be expected to master all these knowledge areas. However, designers need to have access to this knowledge in a simple and clear form, to be able to design products that allow an optimal recovery with minimum quality losses. This is achieved by developing a QuickScan recyclability assessment method based on an exploded view of a product, in which material compatibility and ease of separation of parts are indicated with a simple color scheme. The requirements for the method is derived based on understanding of the design process and learnings from existing recycling tools. The QuickScan recyclability assessment method was tested on a MR16 LED Lamp for method enhancement.","","en","conference paper","Austrian Society for Systems Engineering and Automation","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:8d030ba9-da22-46d3-a018-f5d502e8d1d1","http://resolver.tudelft.nl/uuid:8d030ba9-da22-46d3-a018-f5d502e8d1d1","Optimised control and pipe burst detection by water demand forecasting","Bakker, M.","Rietveld, L.C. (promotor)","2014","Water demand forecasting The total water demand in an area is the sum of the water demands of all individual domestic and industrial consumers in that area. These consumers behave in repetitive daily, weekly and annual patterns, and the same repetitive patterns can be observed in the drinking water demand. The observations of the water demand were used to develop a fully adaptive forecasting model for short-term drinking water demand. The forecasting model automatically stores and updates water demand patterns and demand factors, and uses these when forecasting the water demand for the next 48 hours with 15-min. time steps (192 values). The model uses as single input the measured water demand and calendar information that appoints deviant days. The model is easy to implement, fully adaptive and accurate, which makes it suitable for application in real time control and pipe burst detection. The model was tested on datasets containing six years of water demand data in six different areas in the central and southern part of Netherlands. The areas vary in size from very large (950,000 inhabitants) to small (2,400 inhabitants). The mean absolute percentage error (MAPE) for the 24-hours forecasts varied between 1.44-5.12%, and for the 15-min. time step forecasts between 3.35-10.44%. When using temperature information as extra input, the average forecasting errors could be reduced by 6.3%, and the largest forecasting errors by 9.4%. ? Optimised control A first application of a short-term water demand forecasting model is using it for optimised control of water supply systems. The conventional automatic control of the production flow or the clear water pumps is often quite simple, resulting is highly varying production or transportation flows. This basic control results in sub-optimal operation of the system, and the operation can be improved when forecasts of the water demands in the system are used. To assess the differences between conventional basic control and optimised predictive control, five existing water supply systems in the Netherlands and one system in Poland were examined. The operational results in a period with conventional control were compared to the results in a period with optimised control. The results showed that the variation in the production flow was 75% lower with optimised control, which resulted in 17% lower turbidity rates in the clear water. The optimised control also resulted in a reduction of the energy costs of 5.2% at the Dutch systems and 11.5% at the Polish system. Pipe burst detection A second application of a short-term water demand forecasting model is using it for pipe burst detection. The now-cast of the water demand a good estimator for the actual water demand under normal circumstances. By comparing the measured water demand to this forecasted water demand, anomalies like pipe bursts can be detected. A pipe burst detection method based on this principle was developed. In the method, all measured and forecasted signals are transformed to moving averaged values over time frames of 2 up to 240 minutes. The transformation to longer moving average time frames resulted in lower threshold values which enabled the detection of smaller pipe bursts. The threshold values that distinguish between normal forecasting inaccuracies and pipe bursts, are derived by evaluating the forecasting deviations in the year prior to the monitoring year. The method was tested on different historic datasets with hydraulic data and pipe burst information in three areas in the western part of the Netherlands, and six areas in the northern part of the Netherlands. The method proved to be effective for detecting the relatively larger bursts: 80-90% of the bursts could be detected within 20 minutes, while generating false alarms on 3% of the days without a burst. The size of the pipe burst that can be detected showed a strong relation with the size of the area. Based on an analysis of problematic bursts, it was found that the burst detection method can effectively be applied to areas with an average demand of 150 m3/h or less.","water supply; water distribution system; demand forecasting; heuristic model; advanced control; pipe burst detection","en","doctoral thesis","","","","","","","","","Civil Engineering and Geosciences","Water Management","","","","52.133326, 5.366885"
"uuid:38e6e347-008c-4fff-9ed8-b302203b5b25","http://resolver.tudelft.nl/uuid:38e6e347-008c-4fff-9ed8-b302203b5b25","Exact versus Dupuit interface flow in anisotropic coastal aquifers","Bakker, M.","","2014","The Dupuit solution for interface flow toward the coast in a confined aquifer is compared to a new exact solution, which is obtained with the Hodograph method and conformal mapping. The position of the toe of the interface is a function of two dimensionless parameters: the ratio of the hydraulic gradient upstream of the interface where flow is one-dimensional over the dimensionless density difference, and the ratio of the horizontal hydraulic conductivity over the vertical hydraulic conductivity. The Dupuit interface, which neglects resistance to vertical flow, is a very accurate approximation of the exact interface for isotropic aquifers. The difference in the position of the toe between the exact and Dupuit solutions increases when the vertical anisotropy increases. For highly anistropic aquifers, it is proposed to add an effective resistance layer along the bottom of the sea in Dupuit models. The resistance of the layer is chosen such that the head in the Dupuit model is equal to the head in the exact solution upstream of the interface where flow is one-dimensional.","interface flow; seawater intrusion; exact solution; Dupuit solution; hodograph","en","journal article","American Geophysical Union","","","","","","","2015-04-13","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:212942ba-1982-49f4-9fc5-8b9924ec64e6","http://resolver.tudelft.nl/uuid:212942ba-1982-49f4-9fc5-8b9924ec64e6","LIBS inspection and particle segregation in the transport of recycled concrete waste","Xia, H.; Bakker, M.C.M.","","2014","","","en","conference paper","Chinese LIBS community","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:10431893-d0cb-4715-9d37-86e6ac139f63","http://resolver.tudelft.nl/uuid:10431893-d0cb-4715-9d37-86e6ac139f63","Het dak als bouwlocatie","Alewijn, N.; Bakker, L.; Geerts, S.; Mellas, Z.; Middelveld, C.; Schaafsma, B.; Simkens, B.; Van der Van der Velde, S.","","2014","","optoppen; luchtgebonden bouwen","nl","report","TU Delft","","","","","","","","Architecture and The Built Environment","","","","",""
"uuid:5e2c444b-0354-41d4-b9b9-7407dc38b6db","http://resolver.tudelft.nl/uuid:5e2c444b-0354-41d4-b9b9-7407dc38b6db","Recycling end-of-life concrete: The C2CA project","Di Maio, F.; Lotfi, S.; Rem, P.C.; Bakker, M.; Hu, M.","","2014","","","en","lecture notes","","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:44cf1a8c-a278-493a-a67e-d983f5ad5c0b","http://resolver.tudelft.nl/uuid:44cf1a8c-a278-493a-a67e-d983f5ad5c0b","Advanced control of a water supply system: A case study","Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.","","2014","Conventional automatic production flow control and pump pressure control of water supply systems are robust and simple: production flow is controlled based on the level in the clear water reservoir and pump pressure is controlled on a static set-point. Recently, more advanced computer-based control methods were developed in which production flow is controlled by using a short-term water demand forecasting model and pressure is controlled by a dynamic pressure control module. To assess the differences between conventional and advanced control, we examined operational data of water treatment plantGruszczyn that supplies drinking water to a part of the city of Pozna?, Poland. We compared two periods of three weeks of conventional and advanced control. The comparison showed that with advanced control the variation in the production flow was 83% lower, and the pump pressure of the clear water pumps was 29% lower. The lower pressure resulted in 20% less background leakage and the overall system's energy costs were 11.5% lower.","optimal control; pressure management; water demand forecasting","en","journal article","IWA Publishing","","","","","","","2015-04-01","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:8204fa5b-9c7b-4caa-b590-74bb733362fc","http://resolver.tudelft.nl/uuid:8204fa5b-9c7b-4caa-b590-74bb733362fc","Detecting Pipe Bursts Using Heuristic and CUSUM Methods","Bakker, M.; Jung, D.; Vreeburg, J.; Van de Roer, M.; Lansey, K.; Rierveld, L.","","2014","Pipe bursts in a drinking water distribution system lead to water losses, interruption of supply, and damage to streets and houses due to the uncontrolled water flow. To minimize the negative consequences of pipe bursts, an early detection is necessary. This paper describes a heuristic burst detection method, which continuously compares forecasted and measured values of the water demand. The forecasts of the water demand were generated by an adaptive water demand forecasting model. To test the method, a dataset of five years of water demand data in a supply area in the Western part of the Netherlands was collected. The method was tested on a subset of the data (only the winter months) in which 9 (larger) burst events were reported. The detection probability for the reported bursts was 44.4%, at an acceptable rate of false alarms of 5.0%. The results were compared with the CUSUM method, which is a general statistical process control (SPC) method to identify anomalies in time series. The heuristic and CUSUM methods generated comparable results, although rate of false alarm for the heuristic method was lower at the same detection probability.","pipe burst detection; demand forecasting; SPC methods","en","journal article","Elsevier","","","","","","","","Applied Sciences","QN/Quantum Nanoscience","","","",""
"uuid:a024327c-412f-4bf8-a659-05a09a2fc800","http://resolver.tudelft.nl/uuid:a024327c-412f-4bf8-a659-05a09a2fc800","How to Use COMSOL Multiphysics for coupled dual-permeability hydrological and slope stability modeling","Shao, W.; Bogaard, T.A.; Bakker, M.","","2014","Preferential flow paths, such as cracks, macropores, fissures, pipes etc. are common features of highly heterogeneous slopes. During intense rainstorms, preferential flow has a significant influence on subsurface flow and slope stability. Dual-permeability models are widely used to simulate preferential flow, but have not been incorporated into hydro-mechanical models. In this study, the COMSOL Multiphysics software was used to couple a dual-permeability model with a soil mechanics model for landslide stability evaluation on a hillslope scale with examples of up to 100m spatial scale. Detailed information is provided on how to incorporate current hydrological and soil mechanics theories into COMSOL. The model is benchmarked against two existing solutions and is applied to evaluate the effect of preferential flow on slope stability as an example.","preferential flow; dual-permeability model; local factor of safety; slope stability analysisd; COMSOL Multiphysics","en","journal article","Elsevier","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:ea5858ea-e0b0-4360-a0a5-01dbb4605cec","http://resolver.tudelft.nl/uuid:ea5858ea-e0b0-4360-a0a5-01dbb4605cec","Improving the Performance of Water Demand Forecasting Models by Using Weather Input","Bakker, M.; Van Duist, H.; Van Schagen, K.; Vreeburg, J.; Rietveld, L.","","2014","Literature shows that water demand forecasting models which use water demand as single input, are capable of generating a fairly accurate forecast. However, at changing weather conditions the forecasting errors are quite large. In this paper three different forecasting models are studied: an Adaptive Heuristic model, a Transfer/-noise model, and a Multiple Linear Regression model. The performance of the models was studied both with and without using weather input, in order to assess the possible performance improvement due to using weather input. Simulations with the models showed that when using weather input the largest forecasting errors can be reduced by 11%, and the average errors by 7%. This reduction is important for the application of the forecasting model for the control of water supply systems and for anomaly detection.","demand forecasting; short term; weather input; transfer/-noise model; MLR model","en","journal article","Elsevier","","","","","","","","Applied Sciences","QN/Quantum Nanoscience","","","",""
"uuid:a57a0d91-98c5-462b-a973-9db0c2b6f3ad","http://resolver.tudelft.nl/uuid:a57a0d91-98c5-462b-a973-9db0c2b6f3ad","The use of questionnaires in colour research in real-life settings: In search of validity and methodological pitfalls","Bakker, I.C. (TU Delft Applied Ergonomics and Design); van der Voordt, Theo (TU Delft Real Estate Management); Vink, P. (TU Delft Applied Ergonomics and Design); de Boon, J","","2014","This research discusses the validity of applying questionnaires in colour research in real life settings.
In the literature the conclusions concerning the influences of colours on human performance and well-being are often conflicting. This can be caused by the artificial setting of the test process. Applying questionnaires could also be a cause. To avoid the disadvantages of an artificial setting, a colour research process was organized in a real life setting. In order to get a better understanding of the validity and possible pitfalls in using questionnaires, the responses to the questionnaires were analysed. During colour research looking for the colour influences on perceived productivity, social cohesion and well-being during meetings, responses to questionnaires were compared with findings from observations of behaviour and additional interviews with the respondents. Discrepancies were found indicating weaknesses of applying questionnaires in colour research. The findings suggest that questionnaires alone are not a fully appropriate tool to establish the colour influences. Triangulation by observations, additional interviews and sampling techniques can improve the validity of measuring the influence of different colours.","questionnaires; observations; methodology; social psychology; colour influences","en","journal article","","","","","","Accepted Author Manuscript","","","","","Applied Ergonomics and Design","","",""
"uuid:e53bc84e-9bd9-4e34-8be5-514384e9ec42","http://resolver.tudelft.nl/uuid:e53bc84e-9bd9-4e34-8be5-514384e9ec42","Pleasure, arousal, dominance: Mehrabian and Russell revisited","Bakker, I.C. (TU Delft Applied Ergonomics and Design); van der Voordt, Theo (TU Delft Real Estate Management); de Boon, J; Vink, P. (TU Delft Applied Ergonomics and Design)","","2014","This paper presents a discursive review of the dimensions pleasure, arousal and dominance that Mehrabian and Russell developed in 1974 to assess environmental perception, experience, and psychological responses. Since then numerous researchers applied these dimensions to assess the experience of the physical environment and its perceived qualities. Although the dimensions appeared to be useful, there is a long-lasting debate going on among environmental psychologists about the interpretation of pleasure, arousal and dominance and its underlying mechanisms. Due to the lack of clarity researchers use different adjectives to describe environmental experiences, which makes any comparison between research findings difficult.
This paper shows that the three dimensions can be linked to the current ABC Model of Attitudes: pleasure, arousal and dominance can be respectively related to affective, cognitive and conative responses , i.e. Affect, Cognition and Behaviour (ABC). In addition, connecting the three dimensions to the triad feeling, thinking and acting, can also help to improve our understanding, interpretation and measurement of pleasure, arousal and dominance. Based on this review, it is proposed to re-introduce the three dimensions and to replace the nowadays often used two dimensional model with pleasure and arousal by a three dimensional model, including dominance as a third dimension, to represent the complete range of human responses.","pleasure; arousal; dominance; ABC psychology; tripartite view of feeling; thinking; acting; experience","en","journal article","","","","","","Accepted Author Manuscript","","","","","Applied Ergonomics and Design","","",""
"uuid:b6fdabd5-efd4-4b28-8429-e48fb9eb7892","http://resolver.tudelft.nl/uuid:b6fdabd5-efd4-4b28-8429-e48fb9eb7892","Developments in European Ecodesign Policy and the Prospects for Design for Sustainable Practices","Nilstad Pettersen, I.; Bakker, C.A.","","2013","European ecodesign policy is currently bringing material resource efficiency into focus. This paper explores how and to what extent policy addresses sustainable consumption-related issues, and what the consequences may be for the future role of design in supporting sustainable everyday consumption. How will policy help and hinder designers and others in creating change? The paper focuses on the prospects for practice-oriented design, which sees resource consumption as happening in and for the sake of social practices. It first introduces design for sustainable practices as currently explored in academia, highlighting features that distinguish it from ecodesign. Secondly, it turns to policy to describe and assess relevant instruments and envisaged changes. Based on that, and informed by practice theory and literature on the impact of policy on innovation, it discusses the potential impact of ecodesign policy on the prospects for design for sustainable practices. Finally, the paper turns the question around and asks what a practice-oriented policy might look like.","sustainable consumption; design for sustainability; practice theory; ecodesign policy","en","conference paper","","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:1bee883c-6fc4-4b01-96a6-916b68f1f2e2","http://resolver.tudelft.nl/uuid:1bee883c-6fc4-4b01-96a6-916b68f1f2e2","""Groundwater recharge: Processes and quantification"": Preface","Bakker, M.; Bartholomeus, R.P.; Ferré, T.P.A.","","2013","","","en","journal article","European Geosciences Union (EGU)","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:29f02251-f7b6-4fec-bda8-5df250519933","http://resolver.tudelft.nl/uuid:29f02251-f7b6-4fec-bda8-5df250519933","A method of separating scrap, and a device","Bakker, M.C.M.; Rem, P.C.; Berkhout, S.P.M.","","2013","The invention relates to a method of and a device for separating scrap comprising scrap items of a first type and of a second type, at least one of said types of scrap comprising metal. According to the invention, the method comprises the steps of passing a spot of light over the surface of a scrap item, and performing a plurality of successive light intensity measurements of light reflected from the surface to collect data from said light intensity measurements, and computing the type of scrap item based on the data; and performing a separation based on the type of scrap item.","","en","patent","European Patent Office","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:0631a3f6-b66c-49d1-9ed2-49877702f42c","http://resolver.tudelft.nl/uuid:0631a3f6-b66c-49d1-9ed2-49877702f42c","Reliability of quay walls using finite element analysiscalibration of partial safety factors in quay wall design by probabilistic plaxis calculations","Wolters, H.J.; Bakker, K.J.; De Gijt, J.G.","","2013","During the last two years, CUR committee 183 has worked on the upgrade of the Dutch Quay Walls handbook (CUR 211), which is to be published in 2013. Two of the main elements that are considered in this new edition are the addition of Finite Element analysis (FEM) as a method for design, comparable to the description in the Handbook Sheet-Pile Structures (CUR 166), and the calibration of partial safety factors design with FEM.With respect to the actuality of this update it must be remembered that with the new 2nd Maasvlakte and other changes in the Rotterdam harbour area, several quay walls are under construction. The research is done for two different types of quay wall, modelled in Plaxis. To begin with, an anchored sheet-pile with two different sheet-pile lengths (21m and 23m) was analysed.For the anchored sheet-pile the target reliability is well approached for the mechanisms wall failure in bending and anchor failure in tension, when designing according to the FEM design prescriptions of CUR 166. The obtained reliability index for soil mechanical failure is too low, but this is mainly due to the used calculation method.","quay walls; finete element; plaxis","en","conference paper","Institute for Research and Community Service","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:9903b2fb-45c1-424f-a232-9e6ce1741f50","http://resolver.tudelft.nl/uuid:9903b2fb-45c1-424f-a232-9e6ce1741f50","Characterization of groundwater dynamics in landslides in varved clays","Van der Spek, J.E.; Bogaard, T.A.; Bakker, M.","","2013","Groundwater dynamics may play a significant role in landslides. A detailed model is developed of the groundwater dynamics in landslides in varved clays in the Trieves area in the French Alps. The varved clays consist of a sequence of alternating silt and clay layers, covered by a colluvium layer and intersected by fissures. The hydraulic conductivity of the clay layers is negligible compared to the silt layers. It is conceptualized that fissures form a hydraulic connection between the colluvium and the varved clays. Groundwater recharge flows through the colluvium into the fissures, where water is exchanged horizontally between the fissure and the silt layers of the varved clays. Groundwater flow in the colluvium is simulated with the Boussinesq equation, while flow in the silt layers of the varved clays is simulated with the Richards equation. Longitudinal outflow from the fissure is simulated with a linear-reservoir model. Scattered data of relatively short monitoring periods is available for several landslides in the region. A good similarity between observed and simulated heads is obtained, especially when considering the lack of important physical parameters such as the fissure width and the distance between the monitoring point and the fissure. A simulation for the period 1959–2004 showed some correlation between peaks in the simulated heads and the recorded occurrence of landslides, while the bottom of the varved clays remained saturated during the entire simulation period.","OA-Fund TU Delft","en","journal article","European Geosciences Union (EGU)","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:ec95e615-d8b8-4d1a-81ed-bec769d1e1b3","http://resolver.tudelft.nl/uuid:ec95e615-d8b8-4d1a-81ed-bec769d1e1b3","Universitair vastgoed als sturingsmiddel in onderwijs en onderzoek","Bakker, I.; van der Voordt, D.J.M.","","2013","Sinds 2010 is Karel Luyben rector magnificus van de Technische Universiteit Delft. Deze universiteit staat nationaal en internationaal hoog aangeschreven en heeft grote ambities voor zowel onderwijs als onderzoek. De Delftse campus biedt ruimte aan zo’n 18.000 studenten en 4.500 medewerkers. Zijn er specifieke kenmerken van een campus aan te wijzen die ervoor zorgen dat studenten en medewerkers er kunnen excelleren? In 2011 publiceerde Alexandra den Heijer haar promotieonderzoek ‘Managing the University Campus’. We vroegen de rector magnificus naar zijn persoonlijke visie op wat een campus tot een goede campus maakt. Naast een enthousiaste manager en wetenschapper blijkt Luyben ook buitengewoon ‘kunst’minnend en mengt hij zich graag binnen alle gelederen en lagen van de TU Delft-gemeenschap. Centraal in zijn visie staat strategisch sturen op verbindingen binnen de campus, met de stad Delft en met andere kenniscentra, nationaal en internationaal.","","nl","journal article","","","","","","","","","","Real Estate and Housing","","","",""
"uuid:a492ceeb-5def-4c39-bf30-f58b38dd0db7","http://resolver.tudelft.nl/uuid:a492ceeb-5def-4c39-bf30-f58b38dd0db7","Advanced control of a water supply system: A case study","Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.","","2013","WTP Gruszczyn supplies drinking water to a part of the city of Pozna?, in the Midwest of Poland. The conventional production flow control and pressure control of the facility was replaced by the advanced control software called OPIR. To assess the differences between conventional and advanced control, production flows and pressures of two operational periods were compared. The comparison showed that advanced control led to 83% less variation in the production flow and 29% lower pressure of the clear water pumps. The lower pressure resulted in 20% less background leakage and the overall energy costs of the system were reduced by 11.5% (337,000 kWh per year).","","en","conference paper","","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:256adb08-d5bd-4240-84cb-1816ac01b481","http://resolver.tudelft.nl/uuid:256adb08-d5bd-4240-84cb-1816ac01b481","Reducing energy consumption and leakage by active pressure control in a water supply system","Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.","","2013","WTP Gruszczyn supplies drinking water to a part of the city of Pozna?, in the Midwest of Poland. For the optimal automatic pressure control of the clear water pumping station, nine pressure measuring points were installed in the distribution network, and an active pressure control model was developed and installed. This model is a hybrid form of a predictive controller and a feedback controller: The model predicts the pressure at the off-line measuring points, based on the adaptively learned relation between distribution flow, and pressure drop between pumping station and measuring point. The predicted pressure is used to derive the set-point for the pumping station. The active pressure control resulted in a reduction of pump energy consumption of 31% (237,200 kWh per year, or 14,300 per year) and a reduction of the water losses of 20%.","energy reduction; leakage; dynamic pressure control; water distribution","en","conference paper","IWA","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:a081e775-93a4-4223-8164-b8efa42156fa","http://resolver.tudelft.nl/uuid:a081e775-93a4-4223-8164-b8efa42156fa","Monitoring van het distributienet om afwijkingen te detecteren","Bakker, M.","","2013","Het drinkwater wordt vanaf de waterzuiveringen naar de onze huizen en bedrijven verpompt via de distributie netwerken. Deze netwerken zijn zeer uitgebreide systemen: naast elke straat en naast veel wegen en door veel weilanden liggen leidingen waardoor het water stroomt. De leeftijd van deze leidingen is divers: in jonge steden of in nieuwe woonwijken zijn de leidingen nog vrij nieuw, maar in de oude stadcentra zijn de leidingen veel ouder, tot soms wel meer dan 100 jaar oud. Het (hoofd) leidingnetwerk in Nederland heeft een totale lengte van circa 120.000 km, ofwel 3 rondjes om de aarde.","","nl","conference paper","Water Management Academic Press","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:7b194dc3-c566-4ec6-be4f-a1a08ee7462b","http://resolver.tudelft.nl/uuid:7b194dc3-c566-4ec6-be4f-a1a08ee7462b","Characterization of groundwater dynamics in landslides in varved clays","Van der Spek, J.E.; Bogaard, T.A.; Bakker, M.","","2013","Groundwater dynamics may play a significant role in landslides. A detailed model is developed of the groundwater dynamics in landslides in varved clays in the Trièves area in the French Alps. The varved clays consist of a sequence of alternating silt and clay layers, covered by a colluvium layer and cut through by fissures. The hydraulic conductivity of the clay layers is negligible compared to the silt layers. It is conceptualized that fissures form a hydraulic connection between the colluvium and the varved clays. Groundwater recharge flows through the colluvium into the fissures where water is exchanged horizontally between the fissure and the silt layers of the varved clays. Groundwater flow in the colluvium is simulated with the Boussinesq equation while flow in the silt layers of the varved clays is simulated with the Richards' equation. Longitudinal outflow from the fissure is simulated with a linear-reservoir model. Scattered data of relatively short monitoring periods is available for several landslides in the region. A good similarity between observed and simulated heads is obtained, especially when considering the lack of important physical parameters such as the fissure width and the distance between the monitoring point and the fissure. A simulation for the period 1959–2004 showed some correlation between peaks in the simulated heads and the recorded occurrence of landslides while the bottom of the varved clays remained saturated during the entire simulation period.","","en","journal article","European Geosciences Union","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:c6216680-d7b2-47a2-b734-1747c686f69e","http://resolver.tudelft.nl/uuid:c6216680-d7b2-47a2-b734-1747c686f69e","A scaling analysis for turbulent shock-wave/boundary-layer interactions","Souverein, L.J.; Bakker, P.G.; Dupont, P.","","2013","A model based on mass conservation properties is developed for shock-wave/boundarylayer interactions (SWBLIs), aimed at reconciling the observed great diversity in flow organization documented in the literature, induced by variations in interaction geometry and aerodynamic conditions. It is the basis for a scaling approach for the interaction length that is valid independent of the geometry of the flow (considering compression corners and incident-reflecting shock interactions). As part of the analysis, a scaling argument is proposed for the imposed pressure jump that depends principally on the free-stream Mach number and the flow deflection angle. Its interpretation as a separation criterion leads to a successful classification of the separation states for turbulent SWBLIs (attached, incipient or separated). In addition, the dependence of the interaction length on the Reynolds number and the Mach numbers is accounted for. A large compilation of available data provides support for the validity of the model. Some general properties on the state of the flow are derived, independent of the geometry of the flow and for a wide range of Mach numbers and Reynolds numbers.","compressible boundary layers; compressible flows; shock waves","en","journal article","Cambridge University Press","","","","","","","2014-01-02","Aerospace Engineering","Aerodynamics and Wind Energy","","","",""
"uuid:b2ecfaee-fa26-4543-9e9d-cd2093e92387","http://resolver.tudelft.nl/uuid:b2ecfaee-fa26-4543-9e9d-cd2093e92387","Red or blue meeting rooms: does it matter? The impact of colour on perceived productivity, social cohesion and wellbeing","Bakker, I.C. (TU Delft Applied Ergonomics and Design); van der Voordt, Theo (TU Delft Real Estate Management); de Boon, J; Vink, P. (TU Delft Applied Ergonomics and Design)","","2013","The purpose of this research is to establish the influences of the colours red and blue on perceived well being, social cohesion and productivity in complex real life work conditions during regular meetings.
Methodology: Seven regular government teams held seven regular meetings in a red, blue and reference meeting room. In literature it is often mentioned that red is a warm and blue a cool colour. To be able to test the warmth and coldness effects we have amplified the warm and cold qualities with light colour and colour of the table top desk. We asked employees to complete questionnaires concerning perceived well being, social cohesion and productivity. Fifty two subjects completed three questionnaires, at the start, the end and two or three days after the meeting. Data were analysed with SPSS 16.
Our findings didn’t show any effects of the red and blue environment on perceived well being, social cohesion and productivity. We assume the processes in real life work situations are too complex to measure influences. Practical implications are that statements frequently mentioned in literature concerning influences of red and blue might be not valid in real life meeting settings. New ways of testing the impact of colours should be reconsidered. Because lab situations are too simplified and artificial, we suggest testing influences of colour in an isolated setting in relation to art.
The originality of this research concerns testing colour influences in complex real life work settings like meetings.","meeting rooms; colour influences; red and blue; perceived productivity","en","journal article","","","","","","Accepted Author Manuscript","","","","","Applied Ergonomics and Design","","",""
"uuid:46c392be-ecdb-46c8-9470-a09f429705a2","http://resolver.tudelft.nl/uuid:46c392be-ecdb-46c8-9470-a09f429705a2","Eco-design opportunities for critical material supply risks","Peck, D.P.; Bakker, C.A.","","2012","A number of recent publications point to the important role of eco-design approaches in risk mitigation for critical materials supply. The core of eco-design is life cycle thinking – usually as some form of Life Cycle Assessment (LCA) approach together with a set of generic guidelines such as checklists, etc. There has however been little appraisal of the extent to which eco-design offers opportunities in the context of critical material supply risks. It is this gap that this paper will tackle. Through research with 30 companies in The Netherlands, a small number see the phenomena of critical materials as an opportunity to seek competitive advantage via new product designs. There is also evidence that those companies see opportunities via an eco-design based approach but there are some issues that need to be addressed before such eco-design approaches could be more successful and used widely.","","en","conference paper","Fraunhofer Verlag","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:bada92a9-9ec1-499e-903e-274f2a101afa","http://resolver.tudelft.nl/uuid:bada92a9-9ec1-499e-903e-274f2a101afa","Challenging the portfolio of powertrains perspective: Time to choose sides","Bakker, S.; Van der Vooren, A.","","2012","In this viewpoint paper we challenge the portfolio perspective that envisions a future in which a wide variety of automotive powertrains and fuels will co-exist. We argue that this perspective is driven by normative ideas and rhetoric and that it is more likely that a very limited set of rather similar technologies will survive as successors to the fossil fuel powered internal combustion engine. Economies of scale of core components and the necessary build-up of infrastructures will eventually give these a decisive lead over its competitors. Our perspective has two implications. First, the cars of the future are and will be competitors and hence there will be winners and losers. Second, policy should be targeted at the set of technologies that are most desirable from a societal and environmental perspective, rather than at the wide variety that is being developed today. Given the challenges of climate change and local air pollution, the electrification of the powertrain should be prioritized at the expense of alternative fuels such as natural gas and biofuels","cars of the future, dominant design, innovation","en","conference paper","World Electric Vehicle Association","","","","","","","","OTB Research Institute for the Built Environment","OTB Research","","","",""
"uuid:08b661bb-6bec-4fc8-890e-d19638e1a2c1","http://resolver.tudelft.nl/uuid:08b661bb-6bec-4fc8-890e-d19638e1a2c1","Purification of post-consumer steel crap","Rem, P.C.; Van den Broeck, F.; Bakker, M.C.M.","","2012","Post-consumer steel scrap is often hand picked for contaminants such as copper to meet specifications of steelmakers. If the hand sorting capacity exceeds 20 tons scrap/h the efficiency generally becomes problematic, leaving 50% of the copper contaminants in the steel product. In response, new technologies are emerging that facilitate hand sorting of these types of scrap. Advantages are increased revenues, expanded plant capacity and higher and more consistent steel product quality. Proposed is a shape-sensitive magnetic separator that pre-sorts scrap into two products. One product is a bulky thinwalled steel fraction of high purity and the other a volumetrically small flow of relatively heavy parts including the contaminants. The concentrated contaminant product is amenable for effective sorting by hand pickers or for sensor sorting, but could also be sold directly to specialized sorters that extract the copper. Detailed results for the magnetic sorter are reported for mid-sized IBA scrap.","stteel scrap; recycling; hand picking; sensor sorting; magnetic sorter","en","journal article","Maney","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:19ad57bd-054e-4c88-8f26-598676853f1a","http://resolver.tudelft.nl/uuid:19ad57bd-054e-4c88-8f26-598676853f1a","The use of an adaptive water demand prediction model","Bakker, M.; Vreeburg, J.H.G.; Rietveld, L.C.; Blom, T.; Van der Roer, M.","","2012","","","en","conference paper","","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:596da00d-5858-4b1c-99b4-68218699cfd4","http://resolver.tudelft.nl/uuid:596da00d-5858-4b1c-99b4-68218699cfd4","Detecting pipe bursts by monitoring water demand","Bakker, M.; Vreeburg, J.H.G.; Van der Roer, M.; Sperber, V.","","2012","An algorithm which compares measured and predicted water demands to detect pipe bursts was developed and tested on three data sets of water demand and reported pipe bursts of three years. The algorithm proved to be able to detect bursts where the water loss exceeds 30% of the average water demand in the area. The accuracy depends on the acceptable number of false alarms By simultaneously running the algorithm in adjacent supply areas, and combining the monitoring results the number of false alarms could be reduced.","demand prediction; pipe burst; detection","en","conference paper","International Water Association","","","","","","","","Civil Engineering and Geosciences","Water management","","","",""
"uuid:55930a1e-61ba-4bec-8fd8-0d96eaca5db3","http://resolver.tudelft.nl/uuid:55930a1e-61ba-4bec-8fd8-0d96eaca5db3","Multiscale Structure-Performance Relationships in Supported Palladium Catalysis for Multiphase Hydrogenations","Bakker, J.J.W.","Moulijn, J.A. (promotor); Kapteijn, F. (promotor); Kreutzer, M.T. (promotor)","2012","The performance of heterogeneous catalysts in multiphase reactions in general is governed by different types of extrinsic and intrinsic structural effects on all length scales, i.e., on the macro- (m to cm), meso- (mm to µm), and microlevel (nm). This PhD research, with a catalysis-engineering approach, focused on several of these multiscale structure-performance relationships of supported palladium (Pd) catalysts applied in, industrially important, multiphase hydrogenations. The structure-performance relationships were studied in various batch and continuous reactors of which most are related to important topics in process intensification such a monolithic reactors and flow chemistry. The performance of monolithic Pd catalysts was enhanced by combining a new type of structured highly porous monoliths with a pressure pulse generating gas-liquid flow (i.e., Taylor flow). This induced a convective flow inside the ‘open’ monolith walls thereby enhancing the mass exchange with the Pd catalyst. This favourable result opens the avenue to higher catalyst loadings without increasing internal mass transfer limitations. Furthermore, a proof of concept study showed that a cheap and readily available gas chromatography capillary, wall-coated with an alumina-supported Pd catalyst and operated in the Taylor flow regime, can be used to synthesize high-value products and to rapidly produce (visual) information about catalytic hydrogenations. This Pd capillary flow device is an excellent alternative for expensive microchip technology and bulky round-bottom flasks. Finally, the intrinsic property of Pd to absorb hydrogen into its crystal lattice was shown to have a strong influence on its performance in the hydrogenation of aromatic nitriles. The transformation into stable Pd ?-hydride above a certain threshold hydrogen pressure induced a persistent change in activity and by-product selectivity.","Heterogeneous catalysis; Hydrogenation; Structured reactors; Palladium; Monoliths; Flow chemistry; Catalyst performance; Nitriles; Azides; Alkynes; Taylor flow; Residence time distribution; process intensification; Multiphase hydrogenation","en","doctoral thesis","","","","","","","","","Applied Sciences","Chemical Engineering","","","",""
"uuid:ec1cea78-16b7-4a3f-a27f-e4b92af78085","http://resolver.tudelft.nl/uuid:ec1cea78-16b7-4a3f-a27f-e4b92af78085","VibroCav: Hydrodynamic Vibration and Cavitation Technology","Bakker, T.W.","Witkamp, G.J. (promotor); Kramer, H.J.M. (promotor)","2012","Vibration and cavitation can be generated in many ways and serve many useful purposes. This study describes physical aspects of useful vibration and cavitation for a broad spectrum of applications at atmospheric or elevated pressures. After a review of available devices, hydrodynamic vibrating-body-in-pipe tools as described in patents by Ivannikov are identified as having a major potential and being largely unexplored. Major advantages of these tools are simplicity of construction, scalability, powerful effects and attractive frequency range for well cleaning applications. Self induced vibration with a free body colliding with the pipe wall causes alternating flow around the body with a water hammer effect that enhances the vibration and cavitation. Cavitation can thus be generated at lower flow rates and at higher backpressures than with passive tools such as orifices. Cavitational collapse at high backpressure creates exceptionally strong effects, giving access to novel applications. At backpressures where even water hammer enhanced cavitation ceases to exist, very strong vibrations persist to pressure levels encountered in deep wells. This unique dual enhanced vibration and cavitation behaviour of the tools is the key to vibrating-body-in-pipe technology for which the new name VibroCav was coined. The study focuses on VibroCav tools with balls, except for one series of tests with a so-called flip-flop body. Exploratory tests in a 350 bar test circuit in Assen lead to the design of a 50 bar laboratory closed test circuit installed in the 3ME lab in Delft with facilities to apply up to 10 bar backpressure and up to 40 bar pressure differentials over the tools. In the 50 bar test circuit many experiments were carried out, firstly with bottom supported balls in a straight pipe and secondly with hanging balls in a pipe with a conical outlet allowing remote adjustment of the gap between the ball and the pipe wall. The influence of water composition, gas content and various ball materials was tested. Selected high backpressure test were carried out with a 350 bar closed test circuit in Drachten. A total of 29 field trials on an industrial scale were carried out for cleaning the porous media around water and oil wellbores under widely varying conditions and 5 field trials were done to evaluate the potential of the technology for the removal of scale deposits in wellbores. The laboratory experiments with the 50 bar test circuit delineated various operational modes of the VibroCav tools as function of flow rate and backpressure with regimes designated as (i) vibration only, (ii) active cavitation always combined with vibration, (iii) no vibration and passive cavitation and (iv) no vibration and no passive cavitation. The vibration regime persists to the maximum backpressure that could be reached and probably to much higher pressures, however at high flow rate conditions and a narrow gap vibration ceases when the Re value increases beyond the point of drag reduction due to shifting of the boundary separation point (Re approximately 3 x 105 for unbounded flow). Active cavitation is just as passive cavitation subdued by increasing backpressure; but in this test circuit it has still been observed at a backpressure of 63 barg. With a bottom supported tool as used in this test circuit a significant path downstream of the ball is obscured and active cavitation closer to the gap might still exist. This is the basis for the expectation that for this tool active cavitation may survive up to 100 barg backpressure. Tools with a hanging ball, in which cavitation is more clearly visible, were not tested at such high backpressures. The influence of water quality and gas content proved to be insignificant. Lightweight balls showed in bottom supported tools violent vibration and strong active cavitation but were easily damaged by the high contact forces between the ball and the support. With hard steel balls and softer steel supports, bedding-in is observed due to contact forces beyond the elastic limit of the support. If the ball is softer than the support, the ball flattens, breaks or is otherwise damaged by the support. The field trials for cleaning porous media around wellbores combined with theoretical analysis provided valuable semi-quantitative understanding of the influence of frequency, source directivity, source energy, wellbore geometry and permeability damage on the penetration depth of sources for vibration based well cleaning. The most significant wave energy for cleaning porous media is provided by the slow Biot wave, which is a compressional wave in fluid in the interconnected pore network. The higher the virgin permeability of the rock and the lower the wave frequency the better is the penetration depth. Permeability deterioration due to pore fouling reduces the penetration depth of the cleaning treatment and with progressive fouling the pore damage may get out of reach of the cleaning tools. The limited number of scale removal trials showed significant potential of the VibroCav tools due to the combination of physical hammering, jetting, wave energy and shock waves of collapsing cavitation bubbles. The study provides a solid basis for a scientifically founded continuation of the development of VibroCav technology for many areas of application in several industrial sectors and should be regarded as the precursor for a range of innovating techniques.","Hydrodynamic; Cavitation; Vibration","en","doctoral thesis","","","","","","","","2012-11-08","Mechanical, Maritime and Materials Engineering","3ME","","","",""
"uuid:44c1e071-0cc6-4349-90e6-cb9b56eb994f","http://resolver.tudelft.nl/uuid:44c1e071-0cc6-4349-90e6-cb9b56eb994f","Monitoring water supply systems for anomaly detection and response","Bakker, M.; Lapikas, T.; Tangena, B.H.; Vreeburg, J.H.G.","","2012","Water supply systems are vulnerable to damage caused by unintended or intended human actions, or due to aging of the system. In order to minimize the damages and the inconvenience for the customers, a software tool was developed to detect anomalies at an early stage, and to support the responsible staff in taking the right decisions to restore the normal situation. The software is designed for water quantity events as well as for water quality events. The model aims to detect events which occur relatively frequently in water distribution systems, like pipe bursts events and water discolouration events. The model does not aim to detect more severe and rare water contaminations.","demand prediction; pipe burst; discolouration; anomaly detection","en","conference paper","IWA","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:e0ce994d-e402-44ef-8bed-10c922542d77","http://resolver.tudelft.nl/uuid:e0ce994d-e402-44ef-8bed-10c922542d77","A business model framework for product life extension","Den Hollander, M.C.; Bakker, C.A.","","2012","Product life extension is an increase in the utilization period of products. Design research on product life extension strategies has so far mainly focused on technical aspects of products, like ‘prevention engineering’ or ‘design for repair, maintenance and upgradability’, and on individual consumer-product relationships, like ‘design for emotional durability’. The viability of product life extension in a business context and the associated consequences for product design, have however remained largely unexplored. In this paper a starting point is provided for this exploration, by outlining the development of a business model framework for product life extension, using strategies for product life extension and mapping these against common elements of contemporary business model theory. Drawing on case studies, examples are used to show how the framework can be used in practice by designers and business developers.","business model; product life extension; strategy; product design; resource use","en","conference paper","","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:f41cb948-7159-4119-9f08-2a5465ea1393","http://resolver.tudelft.nl/uuid:f41cb948-7159-4119-9f08-2a5465ea1393","Reducing customer minutes lost by anomaly detection?","Bakker, M.; Vreeburg, J.H.G.; Rietveld, L.C.; van der Roer, M.","","2012","An method which compares measured and predicted water demands to detect anomalies, was developed and tested on three data sets of water demand of three years in which and 25 pipe bursts were reported. The method proved to be able to detect bursts where the water loss exceeds 30% of the average water demand in the area. By simultaneously running the method in adjacent supply areas, and combining the monitoring results the number of false alarms could be reduced. Further analysis of the reported bursts, showed that most burst (22 of 25) were isolated within 2 hours after occurrence. The anomaly detection method could not have reduced the number of Customer Minutes Lost (CML) of those bursts. The water loss and pressure drop of the other bursts was limited and caused no CML. The detection method was able to detect the bursts, but did not reduce the CML.","","en","conference paper","","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:e7f963dc-c3c8-458a-b851-f82e58f58538","http://resolver.tudelft.nl/uuid:e7f963dc-c3c8-458a-b851-f82e58f58538","Environmental sizing of smartphone batteries","Flipsen, S.F.J.; Geraedts, J.M.P.; Reinders, A.H.M.E.; Bakker, C.A.; Dafnomilis, I.; Gudadhe, A.","","2012","Smartphone use has increased at a phenomenal pace worldwide. In 2011 more smartphones have been sold than desktop pc’s, notebooks, netbooks and tablets together. The total worldwide smartphone sales reached 472 million units in 2011, and 149 million of them were sold in the fourth quarter of 2011. The smartphone is, like almost every other mobile device, powered by batteries, limited in size and therefore capacity, which makes energy management paramount. While global demand and use of mobile devices continuously expands, the energy density of smartphone batteries has grown at an insignificant rate, but the use period still decreases because of high loads and big screens. In this paper we have studied the power breakdown of five smartphones on sale in 2011. We have defined three different user profiles for “heavy”, “moderate” and “light” users and we can state that theoretically it is sensible to re-size the battery based on the user profile. While keeping the user period acceptable we can decrease the battery capacity for moderate and light users with 25%, reducing the worldwide energy needed to product smartphone batteries with 2.1 to 3.4PJ per year. In practice the aging of the battery will result in a decreasing battery capacity over its life. When taking this into account most batteries comply with the moderate users and only a resizing strategy for the light users is sensible. This will account for only 20% of all users and can result in a worldwide decrease of energy needed for producing the smartphone batteries with 0.5 to 0.9PJ.","","en","conference paper","Fraunhofer Verlag","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:a30c3782-d2ef-4558-9f90-19eef3778761","http://resolver.tudelft.nl/uuid:a30c3782-d2ef-4558-9f90-19eef3778761","Rethinking Eco-design Priorities: The case of the Econova television","Bakker, C.A.; Ingenegeren, R.; Devoldere, T.; Tempelman, E.; Huisman, J.; Peck, D.P.","","2012","Eco-design heuristics (defined as experience-based techniques for problem solving) can play a useful role in helping designers prioritize eco-design strategies. One of these eco-design heuristics (the ‘use phase’ heuristic) is: Frequently used electric and electronic products usually have, over their life span, a dominant impact in the use phase. Modern mobile devices like smart phones however have their dominant impact in the production phase and therefore challenge this heuristic. The paper asked whether this could be a trend and whether we might find more electric and electronic products that challenge the ‘use phase’ heuristic. We found that in general, the development of highly energy efficient consumer electronics and the widespread shortening of product lifespans have indeed started to shift the focus to the materials and production phase of the life cycle. The case study of the Econova television showed that with a ‘best in class’ product like this TV, it is not possible to establish which life cycle phase is dominant. These findings led to several additions to the ‘use phase’ heuristic.","","en","conference paper","Fraunhofer Verlag","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:7b05fb16-6ef1-4c47-8c8c-13c304fa25cf","http://resolver.tudelft.nl/uuid:7b05fb16-6ef1-4c47-8c8c-13c304fa25cf","Eddy current separation apparatus, separation module, separation method and method for adjusting an eddy current separation apparatus","Rem, P.C.; Bakker, M.C.M.; Berkhout, S.P.M.; Rahman, M.A.","","2012","Eddy current separation apparatus (1) for separating particles (20) from a particle stream (w), wherein the apparatus (1) comprises a separator drum (4) adapted to create a first particle fraction (21) and a second particle fraction (23), a feeding device (2) upstream of the separator drum (4) for supplying particles (20) to said separator drum (4), and a splitter element (14) provided downstream of the separator drum (4) for splitting the respective fractions (21,23), wherein the apparatus (1) further comprises a sensor device (11,111,211) arranged for detecting particles (20), at least a number and/or material properties thereof, from at least part of one of the particle fractions (21), wherein the separation apparatus (1) is configured to adjust, in use, a position and/or orientation of the splitter element (14) with respect to the separator drum (4); and/or a transporting velocity of the feeding device (2) in dependence of a signal from the sensor device (11,111,211) based on the number and/or material properties of the detected particles (20).","","en","patent","European Patent Office","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:f9186e29-030b-4438-ae77-46396dc68af2","http://resolver.tudelft.nl/uuid:f9186e29-030b-4438-ae77-46396dc68af2","Enhancing capacities of riparian professionals to address and resolve transboundary issues in international river basins: Experiences from the Lower Mekong River Basin","Douven, W.; Mul, M.L.; Fernandez-Alvarez, B.; Lam Hung, S.; Bakker, N.; Radosevich, G.; Van der Zaag, P.","","2012","This paper analyses the design and impact of capacity building programmes aimed at enhancing capacities of riparian professionals to address and resolve transboundary issues in international river basins. The case study is a programme developed by the Mekong River Commission (MRC). A post-training evaluation was applied to assess its impact in terms of individual capacity enhancement and change (use and application of knowledge, factors hampering application, and change in function and opportunities within the organisation). The design of the Capacity Building Programme of the MRC Flood Management and Mitigation Programme required a well balanced range of subjects (such as IWRM (integrated water resources management), model and decision support systems, and international water law). The post-training evaluation, 6 months after the last training workshop, showed an increase in familiarity with the topics for all 37 respondents, with the highest increase for the respondents with few years of working experience and from training and education institutions. The relevance of the subjects taught was highlighted by 95% of the respondents, and 78% of the participants had already used some of the acquired knowledge in their job. The respondents indicated that they did not have sufficient opportunities to apply all knowledge. The phased implementation and training of lecturers during the training workshops had a good impact, directly through increasing involvement in facilitation and delivery of the capacity building programme and through the use of the knowledge gained in short courses and development of curricula at their institute. For these types of capacity building programmes, a few recommendations can be made. The selection of participants is crucial for the application of the learned knowledge in their work. The integrative nature of transboundary water issues calls for a capacity building programme addressing a wide range of subjects, which can be understood by a wide range of professionals from different sectors. Training methods should also address this integrative nature through, e.g. roleplays and case studies. A successful capacity building programme needs to address the three levels of capacity building (enabling environment, organisations, and individual staff) and involve national and regional training and education institutes.","","en","conference paper","European Geosciences Union (EGU)","","","","","","","","Civil Engineering and Geosciences","Water management","","","",""
"uuid:4b86c12a-7458-447e-aba7-dc041c2708c2","http://resolver.tudelft.nl/uuid:4b86c12a-7458-447e-aba7-dc041c2708c2","Alliance formation in the electric vehicle industry during an era of ferment","Sierzchula, W.S.; Bakker, S.; Maat, B.","","2012","","","en","conference paper","","","","","","","","","Technology, Policy and Management","Infrastructures, Systems and Services","","","",""
"uuid:606e3647-52b3-4b6e-ac45-a227ef1892be","http://resolver.tudelft.nl/uuid:606e3647-52b3-4b6e-ac45-a227ef1892be","Credibility and legitimacy in policy-driven innovation networks: Resource dependencies and expectations in Dutch electric vehicle subsidies","Van Rijnsoever, F.J.; Welle, L.; Bakker, S.","","2012","The aim of this paper is to empirically examine the influence of different types of credibility on the legitimacy to grant individual actors within consortia an innovation subsidy. Theorizing from the resource dependence view and the sociology of expectations, we hypothesize that four types of credibility are related to legitimacy: scientific credibility, market credibility, expectation track record, and social capital. Further, we operate on two levels of analysis, the actor and the consortium level. Empirically, we quantitatively analyze the Dutch electric vehicle subsidy program as a case study. We develop a model that accurately forecasts which consortia are most likely to receive subsidies. We demonstrate that social capital and market credibility positively influence the likelihood of receiving innovation subsidies, while scientific credibility sources and expectation track record have a negative influence. Based on these findings we provide policy recommendations and avenues for further research.","electric vehicle technology; expectations; resource dependence view; legitimacy; innovation policy","en","conference paper","DRUID Society","","","","","","","","OTB Research Institute for the Built Environment","OTB Research","","","",""
"uuid:64d30fb2-e7c4-432f-97ef-925f7a37a115","http://resolver.tudelft.nl/uuid:64d30fb2-e7c4-432f-97ef-925f7a37a115","Ultrasound imaging for quantitative measurement of immersed plastic waste particles","Sanaee, S.A.; Bakker, M.C.M.","","2012","Ultrasound imaging techniques are proposed for measuring the shape and thickness of immersed waste particles (10-20 mm size) using a linear sensor array from a fixed position. For these purposes both the front and back surface of a particle needs to be reconstructed. Raw ultrasound pulse-echo and plane wave datasets and different imaging techniques were investigated in a case study using a single, generic test object. Phase shift migration proved the most efficient technique with a good performance, provided the front surface of the particle is plane. In other cases the non-stationary phase shift extrapolator may be applied to generalize this migration technique to particles with a non-plane front surface. Alternatively, SAFT and wave equation redatuming were coupled to obtain an acceptable reconstruction independent of the shape of the front surface. The case study shows that ultrasound imaging has potential as a quantitative assessment tool in immersion solid waste processing.","ultrasound imaging; wave equation redatuming; phase shift migration; non-stationary phase shift migration; SAFT; solid waste; quality control","en","conference paper","WCNDT","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:b9b11401-5654-474c-b332-5900278671f8","http://resolver.tudelft.nl/uuid:b9b11401-5654-474c-b332-5900278671f8","Insights into the design, use and implementation of home energy management systems","Van Dam, S.S.; Bakker, C.A.; Van Hal, J.D.M.","","2012","Between 2008 and 2011, three different home energy management systems (HEMS)that give feedback on energy consumption were implemented in households in the Netherlands. Home energy management systems are defined as intermediary devices that can visualise, monitor and/or manage domestic gas and/or electricity consumption. Through a series of questionnaires, interviews, focus groups and usability tests, a wide range of knowledge was gathered on factors influencing the effectiveness of the three systems. The resulting insights were structured with the help of a conceptual model, which outlines the various interactions between users, energy monitors, and their social and physical environments. The insights provide a broad spectrum of factors to be considered for the successful design and implementation of home energy management systems. This paper aims to provoke an open discussion to ascertain the value of the different factors and further the development of effective and useful HEMS.","energy monitor; smart metering; energy conservation; household energy consumption; feedback; usability; design research; home energy management system; insights; implementation","en","conference paper","Inderscience Enterprises Ltd.","","","","","","","","Architecture","Real Estate and Housing","","","",""
"uuid:48f9a853-cdf3-4219-ae05-891a3c66b7fc","http://resolver.tudelft.nl/uuid:48f9a853-cdf3-4219-ae05-891a3c66b7fc","Erodibility of soft fresh water sediments: The role of bioturbation by meiofauna","De Lucas Pardo, M.A.; Bakker, M.; Winterwerp, J.C.; van Kessel, T.; Cozzoli, F.","","2012","","","en","conference paper","University of Twente","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:73f5290f-1563-45b3-9dd2-023cd7598947","http://resolver.tudelft.nl/uuid:73f5290f-1563-45b3-9dd2-023cd7598947","Online sensor system based on laser-induced breakdown spectroscopy in quality inspection of demolition concrete","Xia, H.; Bakker, M.C.M.","","2012","In the C2CA project, an online sensor system is required to measure and control the quality and homogeneity of demolition concrete continuously. Laser-induced breakdown spectroscopy is a candidate to fulfil the objective in several tasks. Investigated is the ability of LIBS as an online semi-quantitative composition analysis technique. The maximum laser repetition rate of 100 Hz and each measurement by single laser shot within 5 ms enable the online application in real time. The wavelength range between 273 nm and 326 nm is chosen for differentiations between mineral alloys and CaO powder. Principal component analysis is applied to differentiate between slag concrete, cement and calcium oxide samples, as based on the Ca II photon counts at 315.76 nm, 317.916 nm, 393.189 nm and 396.608 nm. The effects of different sample preparation procedures on the laser shot-to-shot repeatability are also characterized. The encouraging results indicate the eligibility of LIBS for online quality inspection of concrete products.","","en","conference paper","International Society for Industrial Ecology","","","","","","","","Civil Engineering and Geosciences","Structural Engineering","","","",""
"uuid:66da6522-e27e-4425-a204-741df3d8d6d3","http://resolver.tudelft.nl/uuid:66da6522-e27e-4425-a204-741df3d8d6d3","Het huisvesten van kennis: Een plek die ons stimuleert zo vrij mogelijk te denken","van der Voordt, D.J.M.; Bakker, I.C.","","2012","Robbert Dijkgraaf is sinds mei 2008 voorzitter van de Koninklijke Nederlandse Akademie van Wetenschappen. Hij is cum laude gepromoveerd, staat bekend als een briljant wetenschapper die de wetenschap toegankelijk maakt voor een groter publiek. FMI trad in gesprek met hem over wetenschappelijk denken en de huisvesting die hier het beste bij past.","","nl","journal article","","","","","","","","","","Real Estate and Housing","","","",""
"uuid:c9bf06a8-1f6a-4fd6-9700-85f569f2a7ba","http://resolver.tudelft.nl/uuid:c9bf06a8-1f6a-4fd6-9700-85f569f2a7ba","Assessing the overall life cycle impact of home energy management systems","van Dam, S.S. (TU Delft OLD Housing Systems); Buiter, J.C. (TU Delft Design for Sustainability); Bakker, C.A. (TU Delft Design for Sustainability)","Durmisevic, E (editor); Pasic, A (editor)","2012","An ever-increasing body of research explores the effectiveness of Home Energy Management systems (HEMS) in achieving energy savings. To date, however, the overall life cycle impact of the HEMS itself has not been taken into account. Thus, no assessment has been made whether the amount of energy saved (esaved) outweighs the energy needed for production, use and disposal (einvested). To determine whether esaved>einvested, a lifecycle assessment was conducted comparing three HEMS in six usage scenarios. The results show that the impact is dependent on the type of HEMS, and that the benefits do not always outweigh the (environmental) costs.","","en","conference paper","International council for research and innovation in building and construction","","","","","Accepted Author Manuscript","","","","","OLD Housing Systems","","",""
"uuid:efbaec68-59de-4294-864f-748901e97f8c","http://resolver.tudelft.nl/uuid:efbaec68-59de-4294-864f-748901e97f8c","The application of Value Improving Practices: Team integration pays off!","Rekveldt, M.G.C.; Smith, J.; Mooi, H.G.; Bakker, H.L.M.; Verbraeck, A.","","2011","Submitted paper to: EURAM 2011 Track 30: Project Organizing","front end development; value improving practices; integrated teams; long term relationships; trust","en","conference paper","Estonian Business School","","","","","","","","Technology, Policy and Management","Multi-Actor Systems","","","",""
"uuid:6e515964-dd95-40ae-89ad-48d82ead499e","http://resolver.tudelft.nl/uuid:6e515964-dd95-40ae-89ad-48d82ead499e","Niet managen, maar faciliteren","Bakker, I.C.; van der Voordt, D.J.M.","","2011","Een lommerrijke entree, een achttiende-eeuwse boerderij met rieten kap, ramen tot op de grond, kasseien, opstapjes, afstapjes. Een hoge werkkamer, licht, uitzicht over de binnenplaats, Afrikaanse beeldjes, schilderijen van Herman Gordijn
en heel veel boeken, ogenschijnlijk slordig opgestapeld, maar zorgvuldig gecategoriseerd naar onderwerp. Een gesprek met Joseph Kessels, specialist in Human Resource Development die, gedreven door nieuwsgierigheid, met passie onderzoekt hoe het beste van de kenniswerker naar boven kan worden gehaald.","","nl","journal article","","","","","","","","","","Real Estate and Housing","","","",""
"uuid:9e322f56-f4a4-4baf-b2c3-7b7bf6287f17","http://resolver.tudelft.nl/uuid:9e322f56-f4a4-4baf-b2c3-7b7bf6287f17","Landscape Architecture at TU Delft 1973-2011: Ter gelegenheid afscheid Prof. Dr. Clemens Steenbergen","Homan, A.; Van der Weide, A.; Bordes, B.; Kwast, B.; Van den Heuvel, D.; Stegewerns, C.; Jongsma, C.; Van Ees, C.; Wouters, C.; Jauslin, D.; Wijnen, D.; Piccinini, D.; Dekker, E.; Van der Kooij, E.; Luiten, E.; De Jong, E.; Toni, F.; Aerts, F.; Verschuure-Stuip, G.; Stotijn, H.; Bakker, I.; Bobbink, I.; Meulenberg, I.; Woltjer, J.; Wilbers, J.; Niemeijer, J.; Lonsdale, J.; Wiers, J.; Pouderoijen, M.; Roos, A.; Hellendoorn, D.; Visser, K.; Storm-Prins, M.; Van der Helm, M.; De Vos, L.; Veldman, M.; Hartveld, M.; Den Ruijter, M.; Verbruggen, N.; Rickert, N.; De Graaf, P.; Van der Ree, P.; Aben, R.; Buijs, R.; Rooij, R.; Van der Velde, R.; De Wit, S.; Nijhuis, S.; Holtappels, S.; Meeks, S.; Van Assen, S.; Van Oosten, S.; Van den Busken, S.; Hermans, W.","","2011","Het is haast onmogelijk om de werkzame jaren van Prof. Dr. Clemens Steenbergen hier op de TU Delft in het kort samen te vatten. Dit is een persoonlijk boek van collega's, medewerkers en studenten ter gelegenheid van zijn afscheid op 15. December 2011.","","nl","book","TU Delft Landscape Architecture","","","","","","","2012-02-09","Architecture","Urbanism","","","",""
"uuid:085a815a-3b94-4190-b4cf-6248906baf8f","http://resolver.tudelft.nl/uuid:085a815a-3b94-4190-b4cf-6248906baf8f","How Molecular Competition Influences Fluxes in Gene Expression Networks","Vos, D. de; Bruggeman, F.J.; Westerhoff, H.V.; Bakker, B.M.","","2011","Often, in living cells different molecular species compete for binding to the same molecular target. Typical examples are the competition of genes for the transcription machinery or the competition of mRNAs for the translation machinery. Here we show that such systems have specific regulatory features and how they can be analysed. We derive a theory for molecular competition in parallel reaction networks. Analytical expressions for the response of network fluxes to changes in the total competitor and common target pools indicate the precise conditions for ultrasensitivity and intuitive rules for competitor strength. The calculations are based on measurable concentrations of the competitor-target complexes. We show that kinetic parameters, which are usually tedious to determine, are not required in the calculations. Given their simplicity, the obtained equations are easily applied to networks of any dimension. The new theory is illustrated for competing sigma factors in bacterial transcription and for a genome-wide network of yeast mRNAs competing for ribosomes. We conclude that molecular competition can drastically influence the network fluxes and lead to negative response coefficients and ultrasensitivity. Competitors that bind a large fraction of the target, like bacterial ?70, tend to influence competing pathways strongly. The less a competitor is saturated by the target, the more sensitive it is to changes in the concentration of the target, as well as to other competitors. As a consequence, most of the mRNAs in yeast turn out to respond ultrasensitively to changes in ribosome concentration. Finally, applying the theory to a genome-wide dataset we observe that high and low response mRNAs exhibit distinct Gene Ontology profiles","","en","journal article","PLOS","","","","","","","","Applied Sciences","Kluyver Centre for Genomics","","","",""
"uuid:5228f2ad-7969-4e5e-97a8-bbdbbf49d5bd","http://resolver.tudelft.nl/uuid:5228f2ad-7969-4e5e-97a8-bbdbbf49d5bd","Radioactive Holmium Acetylacetonate Microspheres for Interstitial Microbrachytherapy: An In Vitro and In Vivo Stability Study","Bult, W.; De Leeuw, H.; Steinebach, O.M.; Van der Bom, M.J.; Wolterbeek, H.T.; Heeren, R.M.A.; Bakker, C.J.G.; Van het Schip, A.D.; Hennink, W.E.; Nijsen, F.W.","","2011","Purpose The clinical application of holmium acetylacetonate microspheres (HoAcAcMS) for the intratumoral radionuclide treatment of solid malignancies requires a thorough understanding of their stability. Therefore, an in vitro and an in vivo stability study with HoAcAcMS was conducted. Methods HoAcAcMS, before and after neutron irradiation, were incubated in a phosphate buffer at 37°C for 6 months. The in vitro release of holmium in this buffer after 6 months was 0.5%. Elemental analysis, scanning electron microscopy, infrared spectroscopy and time of flight secondary ion mass spectrometry were performed on the HoAcAcMS. Results After 4 days in buffer the acetylacetonate ligands were replaced by phosphate, without altering the particle size and surface morphology. HoAcAcMS before and after neutron irradiation were administered intratumorally in VX2 tumor-bearing rabbits. No holmium was detected in the faeces, urine, femur and blood. Histological examination of the tumor revealed clusters of intact microspheres amidst necrotic tissue after 30 days. Conclusion HoAcAcMS are stable both in vitro and in vivo and are suitable for intratumoral radionuclide treatment.","brachytherapy; holmium; in vivo; microspheres; VX2 carcinoma","en","journal article","Springer","","","","","","","","Applied Sciences","Radiation, Radionuclides and Reactors","","","",""
"uuid:02a524f0-ccb5-4eb9-9858-25f205d2da88","http://resolver.tudelft.nl/uuid:02a524f0-ccb5-4eb9-9858-25f205d2da88","Higher energy efficiency and better water quality by using model predictive flow control at water supply systems","Bakker, M.; Verberk, J.Q.J.C.; Palmen, L.J.; Sperber, V.; Bakker, G.","","2011","Half of all water supply systems in the Netherlands are controlled by model predictive flow control; the other half are controlled by conventional level based control. The differences between conventional level based control and model predictive control were investigated in experiments at five full scale water supply systems in the first half of 2011. Energy consumption of the treatment and distribution process and quality parameters of the drinking water were measured and analyzed. The experiments prove that the overall energy consumption of water supply systems controlled by model predictive flow control is 1,5-5% lower than conventionally controlled systems, and the overall energy costs are 2,5-7% lower. Turbidity and particle numbers are 10-20% lower for the systems which are controlled by model predictive flow control.","Prediction; control; water quality; drinking water; energy reduction","en","conference paper","IWW","","","","","","","","Civil Engineering and Geosciences","Water management","","","",""
"uuid:1ff38b79-4582-4ad5-a937-1dc8f0e2a738","http://resolver.tudelft.nl/uuid:1ff38b79-4582-4ad5-a937-1dc8f0e2a738","Using 18th century storm-surge data from the Dutch Coast to improve the confidence in flood-risk estimates","Baart, F.; Bakker, M.A.J.; Van Dongeren, A.; Den Heijer, C.; Van Heteren, S.; Smit, M.W.J.; Van Koningsveld, M.; Pool, A.","","2011","For the design of cost-effective coastal defence a precise estimate is needed of the 1/10 000 per year storm surge. A more precise estimate requires more observations. Therefore, the three greatest storm surges that hit the northern part of the Holland Coast in the 18th century are reconstructed. The reconstructions are based on paintings, drawings, written records and shell deposits that have recently appeared. The storm-surge levels of these storms have been estimated using numerical modelling of the coastal processes. Here we show how these reconstructions can be used in combination with extreme value statistics to give a more confident estimate of low probability events.","","en","journal article","European Geosciences Union","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:f50e0b0e-f855-4566-aa72-3d3e9fc50d12","http://resolver.tudelft.nl/uuid:f50e0b0e-f855-4566-aa72-3d3e9fc50d12","Sensor platform for gas composition measurement","De Graaf, G.; Bakker, F.; Wolffenbuttel, R.F.","","2011","The gas sensor research presented here has a focus on the measurement of the composition of natural gas and gases from sustainable resources, such as biogas. For efficient and safe combustion, new sensor systems need to be developed to measure the composition of these new gases. In general about 6 gas components need to be measured to determine the caloric value and the combustion properties of these gas mixtures. The concentration levels of the relevant components are relatively high, and the emphasis of this research work is therefore on selectivity and avoidance of cross contamination. For this reason and because of their limited stability, chemical sensors are not considered. The sensors in this work are based on physical interaction with the gas. One single sensing principle is insufficient for identification of all components in the natural gas and a microsystem for measuring three different physical properties of the gas components are proposed in this work: thermal conductivity, optical and photo-acoustic infrared absorption.","gas sensor platform: NDIR; photoacoustic gas sensor; thermal conductivity detector; natural gas composition measurement","en","journal article","Elsevier","","","","","","","","Electrical Engineering, Mathematics and Computer Science","Microelectronics","","","",""
"uuid:a1ccd67e-2e1c-4b1f-8aa9-633c673f27e7","http://resolver.tudelft.nl/uuid:a1ccd67e-2e1c-4b1f-8aa9-633c673f27e7","Heterogeneously Catalyzed Continuous-Flow Hydrogenation Using Segmented Flow in Capillary Columns","Bakker, J.J.W.; Zieverink, M.M.P.; Kapteijn, F.; Moulijn, J.A.; Kreutzer, M.T.","","2011","Segmented flow in standard GC capillary columns, with a heterogeneous Pd catalyst on the walls, gave rapid information about catalytic processes in them. The residence time and conversion was monitored visually, greatly simplifying bench-scale optimization. Examples show the benefits of the elimination of pore diffusion and axial dispersion. Further, we demonstrated how to quickly identify deactivating species in multistep synthesis without intermediate workup.","OA-Fund TU Delft","en","journal article","Wiley-VCH","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:f794c017-dab0-4111-99ad-ac00e9787446","http://resolver.tudelft.nl/uuid:f794c017-dab0-4111-99ad-ac00e9787446","Maakt het uit of een vergaderzaal rood of blauw is? Het effect op welzijn, sociale cohesie en productiviteit","Bakker, I.C.; Vink, P.; van der Voordt, D.J.M.; de Boon, J.","","2011","In een reële werksituatie binnen de overheid is een test uitgevoerd om vast te stellen of de kleuren rood en blauw effect hebben op het welzijn, de sociale cohesie en de productiviteit tijdens vergaderingen. Werknemers hebben als testpersonen hun reguliere vergaderingen gehouden verdeeld over een drietal testruimtes: twee vergaderruimtes met rode versus blauwe wanden en een standaard referentieruimte. Tijdens de test zijn de warm-koud effecten van de kleuren rood respectievelijk blauw versterkt. In de rode kamer is naast rode wanden, een vergadertafel geplaatst met houtdesign en is standaard kantoorverlichting toegepast met een kleurtemperatuur van 3500K. In de blauwe kamer zijn naast de toepassing van blauwe wanden, een grijs/witte tafel geplaatst en lampen met een hogere kleurtemperatuur van 5300 K, die een koel effect geeft. Daarnaast is gebruik gemaakt van een referentieruimte met de standaard uitstraling waaraan de proefpersonen waren gewend. Via standaardvragenlijsten zijn alle deelnemers op drie momenten bevraagd over de aspecten welzijn, sociale cohesie en productiviteit. De resultaten hebben derhalve betrekking op percepties. In de drie verschillende omgevingen is geen verschil in effect vastgesteld, noch op welzijn, noch op sociale cohesie, noch op productiviteit. Het feit dat vergaderingen een veelheid van complexe processen kennen, die van de deelnemers aandacht vergen, waarbij zij zich minder bewust zijn van de fysieke omgeving, is hier vermoedelijk de oorzaak van.","kleur in vergaderruimtes; rood en blauw; welzijn; sociale cohesie en productiviteit","nl","report","Technische Universiteit Delft","","","","","","","","","Real Estate and Housing","","","",""
"uuid:1ed20912-4336-4d9a-853d-38b02889e687","http://resolver.tudelft.nl/uuid:1ed20912-4336-4d9a-853d-38b02889e687","Materials scarcity: A new agenda for industrial design engineering","Köhler, A.R.; Bakker, C.; Peck, D.","","2010","Societal stakeholders are expressing concerns over the increasing scarcity of critical elements on which high-tech industries rely. Geochemical rare elements are indispensable in producing high-tech products such as electronic gadgets and renewable energy technologies. The surge in demand for critical elements presents a risk of exhaustion of available mineral resources. The consequences appear severe and may include high price volatility, supply disruptions and geopolitical conflicts. Materials scarcity can affect the transition towards a sustainable society if supply shortages of critical elements curb the proliferation of green technologies. This situation presents the world with a range of multidimensional complex problems, sometimes termed ‘wicked’ problems. Industrial design engineers, with their multidisciplinary design approach, are well equipped to be able to thrive in such a period of change. Industrial design can contribute to more efficient use of scarce materials by exploring design options to eliminate or substitute them. Designing products for longer life spans, and facilitating predicted reuse as well as high intensity recycling can be part of possible solution strategies. This scoping paper reviews important aspects of material scarcity and aims to define and delineate the topic for the industrial design engineering community. The risk of material scarcity poses a challenge in finding innovative approaches and methods that will help to counteract the depletion of scarce materials. This prompts us to re-examine and reframe the curriculum of higher education in industrial design and to outline elements of a new agenda for resource-aware industrial design.","critical elements; higher education; green technologies; rare earths; resource depletion; sustainable design","en","conference paper","","","","","","","","","Industrial Design Engineering","","","","",""
"uuid:eacb0e4c-4b42-461c-bbce-734f1c6d2d7d","http://resolver.tudelft.nl/uuid:eacb0e4c-4b42-461c-bbce-734f1c6d2d7d","Innovation and complex governance at times of scarcity of resources: A lesson from history","Peck, D.P.; Bakker, C.A.; Diederen, A.","","2010","Historians understand the important role that access to critical raw materials has played in the development of civilizations, however access to materials has regularly led to distrust and conflict. Near future material scarcity scenarios appear to be severe and could include a mix of price volatility, supply disruptions and geopolitical tensions. Materials scarcity would affect the supply side of a range of materials upon which high-tech and renewable energy industries rely. Historically, materials restrictions were placed by societies, onto themselves and were generally short term or limited in nature. The current materials scarcity challenge, whilst being self imposed, will be long term and global in nature. One fundamental challenge will be to explore historical case studies that give us a reference point to explore potential responses. There are numerous case studies over the 20th century – mainly driven by conflicts and sanctions. This paper examines one case in particular – that of Britain during World War Two. This case has a number of facets that make it very useful for analysis. The first of these is the length of time – counted in years. Secondly - the materials involved and in particular the metals and the lack of easily available substitutes. Thirdly - the role of secondary sourcing (recycling and reuse). Fourth – it explores the role of government in facilitating change. The final and prime facet of the case is the role of innovation and design. This paper will derive lessons that can be learnt from the case and show clearly how they may give indications of current responses to materials scarcity scenarios.","","en","conference paper","","","","","","","","","Industrial Design Engineering","","","","",""
"uuid:5394f2ff-a45f-48ad-a7b4-94916085ff8c","http://resolver.tudelft.nl/uuid:5394f2ff-a45f-48ad-a7b4-94916085ff8c","Living climate change: Design thinking and learning in complexity","Bakker, C.A.; Peck, D.P.; Soboll, P.; Tempelman, E.","","2010","As the world moves into an era of significant changes predicated by the challenge of sustainability, the future holds many questions, with serious consequences depending on the answers. Given the implications of these changes, the world’s design community needs to be constantly challenged to respond. To support conversations on what life will be like in 20 or 30 years and thus make the climate change debate more tangible, IDEO, a global design and innovation company, is hosting the Living Climate Change project and website. Moving the debate away from what we have to give up toward what we can create, the project is born from the conviction that design has a role to play in addressing the global issue of climate change. The scenarios IDEO developed (in movie clips) show how we may choose (or be forced) to abandon the old ways and change our behaviour. In partnership with IDEO, the Faculty of Industrial Design Engineering of the Delft University of Technology applied the Living Climate Change method in their education on sustainable design. Over a ten-week period, nine student teams were asked to develop non-linear future scenarios and present these in short movie clips. This paper presents the results of this activity, reflects on the methods used (expert involvement, storytelling, scenario building, movie making) and the learning that took place. The main conclusion is that the Living Climate Change activity turned out to be a valuable tool for the students, helping them come to terms with complex and interlinked topics and how these might change the world and the way we live.","design education; design thinking; sustainable design; climate change; constructivistic learning","en","conference paper","","","","","","","","","Industrial Design Engineering","","","","",""
"uuid:02b93737-12d9-480b-b432-407821f4283b","http://resolver.tudelft.nl/uuid:02b93737-12d9-480b-b432-407821f4283b","Insights in using home energy management systems","Van Dam, S.S.; Bakker, C.A.; Van Hal, J.D.M.; Keyson, D.V.","","2010","In an ongoing process, three diverse Home energy management systems (HEMS) have been implemented in the households in the Netherlands. Through a series of questionnaires, interviews, focus groups and usability tests, a wide range of knowledge in being gathered. Because of this broad approach, the insights that are gained are not only limited to the amount of savings that were achieved but also encompass participants understanding of, and control over, thier home energy consumption and the manners in which the HEMS is incorporated into their daily lives. This paper presents the first insights that were gathered through the in-depth contact with users. It aims to provoke an open discussion to further the development of the insights into guidelines for effective and useful HEMS.","home energy management systems; energy monitor; energy saving; conservation; household","en","conference paper","","","","","","","","","Architecture","","","","",""
"uuid:bfc23d6f-0747-45ff-8025-fbbb7dab30a2","http://resolver.tudelft.nl/uuid:bfc23d6f-0747-45ff-8025-fbbb7dab30a2","Geo-informatie kent geen tijd?","Bakker, N.; Breure, L.; Quak, C.W.","","2010","Studiemiddag over temporele aspecten van geografische gegevens, georganiseerd door de Subcommissie Geo-Informatie Infrastructuur van de NCG en Geo-Informatie Nederland (GIN) op donderdag 17 september 2009 te Utrecht.","","nl","book","Nederlandse Commissie voor Geodesie (NCG)","","","","","","","","OTB Research Institute for the Built Environment","OTB Onderzoek","","","",""
"uuid:05e8ce7c-aa82-4f89-be0a-fc473bdc1482","http://resolver.tudelft.nl/uuid:05e8ce7c-aa82-4f89-be0a-fc473bdc1482","Home energy monitors: Impact over the medium-term","Van Dam, S.S.; Bakker, C.A.; Van Hal, J.D.M.","","2010","Home Energy Management Systems (HEMS), e.g. energy monitors, are intermediary products that can visualize, manage, and/or monitor the energy use of other products or whole households. HEMS increasingly receive attention for their role in energy conservation in households. A literature review and a case study examine the mid-term effectiveness (more than 4 months) of HEMS. The case study presents the results of a 15-month pilot with a domestic energy monitor in the Netherlands. It explores the extent to which participants manage to sustain their initial electricity savings over time, with a special focus on the development of habitual energy-saving behaviour. The results show that the initial savings in electricity consumption of 7.8% after 4 months could not be sustained in the medium- to long-term. A second finding is that certain groups of people seem more receptive to energy-saving interventions than others. These participants quickly develop new habits and exhibit larger savings than other participants. Obviously, a ‘one-size-fits-all’ approach for home energy monitors cannot be justified. For HEMS to be effective, a deeper understanding is needed that embraces social science, contextual factors, usability, and interaction design research.","captology; energy demand; energy management; energy monitor; Home Energy Management System (HEMS); housing; occupant behaviour; smart metering; usability","en","journal article","Routledge, Taylor & Francis group","","","","","","","","Architecture","Real Estate & Housing","","","",""
"uuid:80cf52f6-cb7e-4833-a5d0-e48d2a985044","http://resolver.tudelft.nl/uuid:80cf52f6-cb7e-4833-a5d0-e48d2a985044","The influence of plants on productivity: A critical assessment of research findings and test methods","Bakker, I; van der Voordt, Theo (TU Delft Real Estate Management)","","2010","Purpose
This paper aims to review available research into the impact of plants on people and labour productivity in order to test a number of hypotheses and the reliability and validity of “evidence based” statements.
Methodology
An extended literature review has been conducted of research concerning the potential impacts of plants on people and labour productivity. In order to be able to compare the findings of different researchers, an analysis has been made of similarities and dissimilarities with regard to the research context, starting-points and test methods.
Findings
The paper identifies a lack of precise descriptions of the research design and poor comparability between different research with regard to the characteristics of the plant, test persons, test procedures, surrounding conditions and contents of the reports. Although we may conclude that plants can have a positive impact on the productivity of human beings, it is remarkable that in research reports and research papers the properties of the plant itself are only mentioned by exception. The condition of the plant - whether it is healthy or not – is not described at all.
Limitations
“Only” 17 studies and underlying papers were investigated and no new research has been conducted with the proposed improvements.
Practical implications The findings can be used by managers to legitimate investments in plants and by researchers to improve (the comparability of) research into plants.
Originality
In addition to the review of the impact of plants on different types of productivity a vision is presented about the impact of the vitality of plants. Furthermore recommendations are given on how to cope with the methodological problem of poor comparability of research.","plants; vitality; productivity; research methods; comparability; model","nl","journal article","","","","","","Accepted Author Manuscript","","","","","Real Estate Management","","",""
"uuid:9b7217b8-dad2-4a72-826a-960c25cb0b61","http://resolver.tudelft.nl/uuid:9b7217b8-dad2-4a72-826a-960c25cb0b61","Home energy monitors: impact over the medium-term","van Dam, S.S. (TU Delft OLD Housing Systems); Bakker, C.A. (TU Delft Design for Sustainability); van Hal, J.D.M. (TU Delft Sustainable Housing Transformation)","","2010","","","en","journal article","","","","","","Accepted Author Mansucript","","","","","OLD Housing Systems","","",""
"uuid:aecb8605-a68b-4bd5-9a84-7dd05a4078cf","http://resolver.tudelft.nl/uuid:aecb8605-a68b-4bd5-9a84-7dd05a4078cf","Huisvesting als middel tot sociaal-economische vitaliteit","Bakker, I; van der Voordt, Theo (TU Delft Real Estate Management)","","2010","Interview met Alexander Rinnooy Kan.","","nl","journal article","","","","","","","","","","","Real Estate Management","","",""
"uuid:93978356-2706-4236-b410-3f5a8a0ada71","http://resolver.tudelft.nl/uuid:93978356-2706-4236-b410-3f5a8a0ada71","Sustainability in Design Engineering Education; Experiences in Northern Europe","Dewulf, K.; Wever, R.; Boks, C.; Bakker, C.; D'hulster, F.","","2009","In recent years, the implementation of sustainability into the curricula of engineering has become increasingly important. This paper focuses on the experiences of integrating sustainability in Design Engineering education in the academic bachelor programs at Delft University of Technology in The Netherlands, at the University College of West-Flanders in Belgium, and at the Norwegian University of Science and Technology. The different approaches are described and discussed. This paper aims to share insights and lessons learned in how to accomplish true integration of sustainability in bachelor course curricula of Industrial Design Engineering.","design engineering education; sustainability education; course development; sustainable product innovation","en","conference paper","the Japan Society of Mechanical Engineers","","","","","","","","Industrial Design Engineering","Design Engineering","","","",""
"uuid:ccdd7168-c914-4a31-a9ed-233a43ea2b63","http://resolver.tudelft.nl/uuid:ccdd7168-c914-4a31-a9ed-233a43ea2b63","Propagation of a cadmium spill through an impounded river system","Klaver, G.T.; Joziasse, J.; Bakker, I.","","2009","In this paper, the influence of impoundments (sluices, weirs, etc.) and stream components (tributaries, river branches, associated canals) on the metal content in water and suspended particulate matter (SPM) in the Dutch part of the River Meuse is assessed using the decrease in the cadmium content of the particulate and dissolved phase during the transport of a distinct cadmium spill through the river. This anthropogenic spill lasted from July 2005 to June 2006 and is documented by the weekly monitoring results of the Meuse in Eijsden at the Belgian-Dutch border. The monitoring data indicate that cadmium was discharged as a dissolved phase. Redistribution of water towards canals is the cause that during low flow conditions only a limited amount of water with an Eijsden geochemical signature arrives in Keizersveer (near the mouth of the river). During such periods various tributaries and groundwater have significant contributions to the discharge measured in Keizersveer. The monthly variations of cadmium concentrations in total water and SPM, upstream and downstream of the series of impoundments are calculated for the period 1993-2004. Next, the transfer of the cadmium through the impounded part of the river is determined based on the monitoring results obtained in the stations in between and downstream from the impoundments. Finally, possible lag effects of the cadmium spill are quantified using monitoring data obtained in 2006 and 2007. It is concluded that it takes about six months before the cadmium spill is detected in the SPM at the monitoring station of Keizersveer. Leaching of cadmium from the sediment to the surface water may result in high dissolved cadmium concentrations. For a better understanding of the processes in the river system it is essential that the SPM monitoring frequency in river sections downstream of Eijsden is increased, starting with the Keizersveer station. A better system understanding is important in order to define appropriate measures to meet the goals of the Water Framework Directive concerning the chemical status of the Meuse River.","river; water quality; monitoring; contaminant transport; cadmium; suspended matter; CT04.20; Waterkwaliteit en Calamiteiten; CT04.23.11; Zwevend slib en waterkwaliteit; Delft Cluster","en","report","Delft Cluster","","","","","","","","","","","","",""
"uuid:e6a3f355-b606-4634-b19b-4c3e011ac839","http://resolver.tudelft.nl/uuid:e6a3f355-b606-4634-b19b-4c3e011ac839","Holmium-166 poly(L-lactic acid) microsphere radioembolisation of the liver: Technical aspects studied in a large animal mode","Vente, M.A.D.; De Wit, T.C.; Van den Bosch, M.A.A.J.; Bult, W.; Seevinck, P.R.; Zonnenberg, B.A.; De Jong, H.W.A.M.; Krijger, G.C.; Bakker, C.J.G.; Van Het Schip, A.D.; Nijsen, J.F.W.","","2009","","Holmium-166; Yttrium-90; Microspheres; Radioembolisation; Liver malignancies","en","journal article","Springer","","","","","","","","Applied Sciences","Radiation, Radionuclides and Reactors","","","",""
"uuid:7c184273-a4b3-4cfb-bf95-a9ffd9a3d173","http://resolver.tudelft.nl/uuid:7c184273-a4b3-4cfb-bf95-a9ffd9a3d173","Superincentive public transport contracting in the greater Amsterdam area","Bakker, B.; Van de Velde, D.M.","","2009","All suburban/regional bus services around Amsterdam City have been submitted to competitive tendering. This is done under a very innovative form of revenue-based contract that can be classified as a ‘super incentive’ contract. Payments to operators (‘subsidies’) are based on realised passenger revenues and no longer on the costs of supplying public transport. Because of the fact that fare increases are regulated by the authority, increase in revenues can only be achieved by an increase in ridership, which is one of the main long term goals of the authority. At the same time, and to provide for a well-balanced contract, operators are also allowed to re-design services within some strict boundaries set by the authority (such as a detailed minimal level of supply). The awarding procedure was designed such as to lead to a high level of self-regulation, preventing bidders to exaggerate their revenue growth forecasts at tendering in order to win the contract. This paper presents the contractual features and the design of the competitive tendering process that has led to the calibration of the superincentives given to the operators. It also presents the results achieved in terms of passenger growth.","","en","conference paper","","","","","","","","","Technology, Policy and Management","Multi Actor Systems","","","",""
"uuid:bca4653e-1273-4ca1-b7d0-ce80428fea00","http://resolver.tudelft.nl/uuid:bca4653e-1273-4ca1-b7d0-ce80428fea00","Sinusoidal pumping of groundwater near cylindrical inhomogeneities","Bakker, M.","","2009","A new analytic-element solution is presented for a well with a sinusoidal discharge pumping near cylindrical inhomogeneities. Both the transmissivity and the storage coefficient may be different inside each cylinder. The solution consists of separate series solutions inside and outside each cylinder; asymptotic expansions are presented for cases where the sinusoidal period is small and the radius and transmissivity of the cylinder are large. The complex coefficients in the series solutions are determined by requiring continuity of head and normal flow across the boundary of each cylinder resulting in a linear system of complex equations that may be solved with standard methods. The solution represents one of the few analytic solutions for two-dimensional transient groundwater flow in an aquifer with inhomogeneities. Computer implementation requires truncation of the series; machine accuracy may be reached when enough terms are used in the series solutions. The effect of cylindrical inhomogeneities on the amplitude and phase of the head are investigated. The complex behavior suggests it may be difficult to determine location and properties of cylindrical inhomogeneities from pump tests, which confirms reported difficulties of interpreting pump test results from heterogeneous aquifers.","Analytic elements; Cylindrical inhomogeneities; Periodic flow","en","journal article","Springer","","","","","","","","Civil Engineering and Geosciences","Department of Watermanagement","","","",""
"uuid:990ebbf9-657b-46f5-bf00-244c0739d23d","http://resolver.tudelft.nl/uuid:990ebbf9-657b-46f5-bf00-244c0739d23d","Radial Dupuit interface flow to assess the aquifer storage and recovery potential of saltwater aquifers","Bakker, M.","","2009","A new accurate numerical solution is presented for aquifer storage and recovery (ASR) systems in coastal aquifers; flow is approximated as radial Dupuit interface flow. The radial velocities of points on the interface are a function of time, the vertical coordinate, and the dimensionless parameter D (the discharge of the well divided by the product of the hydraulic conductivity, the square of the aquifer thickness, and the dimensionless density difference). The recovery efficiency of an ASR system (the ratio of the recovered volume of water divided by the injected volume of water) is determined by D and by the relative lengths of the injection, storage and recovery periods. Graphs are produced for the recovery efficiency as a function of parameter D for ASR operations with and without storage periods and for multiple cycles. The presented solutions and graphs are to be used as screening tools to assess the feasibility of specific injection, storage and recovery scenarios of planned ASR systems in saltwater aquifers without having to run complicated flow and transport models. When the screening tool indicates that recovery efficiencies are acceptable, the consideration of other features such as mixing and chemistry is warranted.","Aquifer storage and recovery; Salt-water/fresh-water relations; Coastal aquifers; Dupuit interface flow","en","journal article","Springer","","","","","","","","Civil Engineering and Geosciences","Watermanagement","","","",""
"uuid:b9f8fdd7-8654-43b3-831f-544effa7e86c","http://resolver.tudelft.nl/uuid:b9f8fdd7-8654-43b3-831f-544effa7e86c","Ultimate limit state design for linings of bored tunnels: Tübbingbemessung im Grenzzustand der Tragfähigkeit beim Schildvortrieb","Bakker, K.J.; Blom, C.B.M.","","2009","According to modern design codes, such as the Eurocode 7, also Soil Retaining structures should be designed according to Ultimate Limit State analysis, see [1]. From an economic point of view, the design of the lining, i.e. the thickness and reinforcement of it, would be optimal if the loading during construction is less critical than the loading during service life, i.e. to the overburden loading. If necessary one could take measures to prevent that any loading during construction becomes more critical than the overburden loading. If this can be achieved, the structural design would be limited to establishing the overburden pressures, and calculating equilibrium between lining strength and overburden. For optimisation one could use Probabilistic theory and Risk Analytic techniques to establish a sufficient distance between actual loading and design parameters to get the most economic lining thickness and reinforcement. In order to evaluate our present situation with respect to lining design, some observations from engineering practice are iscussed: the first, from the construction of the 2nd Heinenoord tunnel, where the damage to the lining during construction was above average; the second from the construction of the Green Hart tunnel where measurements show, that flexibility of the tube and the influence of interaction between structure and underground can also lead to critical loading conditions for the lining. Finally the analyses and observations are generalized and some conclusions with respect to lining design are drawn.","bored tunnels; lining forces; limit states; design","en","journal article","Ernst & Sohn","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:ac069d55-cb87-474b-9af6-421a07225339","http://resolver.tudelft.nl/uuid:ac069d55-cb87-474b-9af6-421a07225339","Arsenic in drinking water: A worldwide water quality concern for water supply companies","Van Halem, D.; Bakker, S.A.; Amy, G.L.; Van Dijk, J.C.","","2009","For more than a decade it has been known that shallow tube wells in Bangladesh are frequently contaminated with arsenic concentrations at a level that is harmful to human health. By now it is clear that a disaster of an unheard magnitude is going on: the World Health Organization has estimated that long-term exposure to arsenic in groundwater, at concentrations over 500 ?g L?1, causes death in 1 in 10 adults. Other studies show that problems with arsenic in groundwater/drinking water occur in many more countries worldwide, such as in the USA and China. In Europe the focus on arsenic problems is currently confined to countries with high arsenic levels in their groundwater, such as Serbia, Hungary and Italy. In most other European countries, the naturally occurring arsenic concentrations are mostly lower than the European drinking water standard of 10 ?g L?1. However, from the literature review presented in this paper, it is concluded that at this level health risks cannot be excluded. As consumers in European countries expect the drinking water to be of impeccable quality, it is recommended that water supply companies optimize arsenic removal to a level of <1 ?g L?1, which is technically feasible. OA-fund TU Delft","","en","journal article","Delft University of Technology","","","","","","","","Civil Engineering and Geosciences","","","","",""
"uuid:23f6c40a-5756-4a46-bc3e-ee8727c9806a","http://resolver.tudelft.nl/uuid:23f6c40a-5756-4a46-bc3e-ee8727c9806a","Conceptual Design of the FAST-D Formation Flying Spacecraft","Maessen, D.C.; Guo, J.; Gill, E.; Gunter, B.; Chu, Q.P.; Bakker, G.; Laan, E.; Moon, S.; Kruijff, M.; Zheng, G.T.","","2009","The paper presents the latest results in the design of FAST-D, the Dutch micro-satellite for the Dutch–Chinese FAST (Formation for Atmospheric Science and Technology demonstration) formation flying mission. Over the course of the 2.5 year mission, the two satellites, FAST-D and FAST-T, will demonstrate various new technologies and perform observations of atmospheric aerosols and seasonal variations of height profiles in the cryosphere using spectropolarimeter and altimeter payloads on both spacecraft. A conceptual design for the Dutch spacecraft, FAST-D, is presented. Special focus is laid on the design of the attitude determination and control subsystem and on the space-based computing experiments to be performed on this spacecraft. Furthermore, new results in the development of the science payloads on FAST-D, the aerosol characterisation instrument SPEX (Spectropolarimeter for Planetary Exploration) and the altimeter SILAT (Stereo Imaging Laser Altimeter), are described. For SPEX, several design changes have been made to make the instrument more compatible with the FAST mission. For SILAT, an instrument re-design for Earth missions is presented, which results in considerable mass savings as compared to the earlier design.","FAST-D; ADCS; space-based computing; SPEX; SILAT","en","conference paper","","","","","","","","","Aerospace Engineering","Space Engineering","","","",""
"uuid:553f6454-e8fe-4e9a-9082-7f5937357f64","http://resolver.tudelft.nl/uuid:553f6454-e8fe-4e9a-9082-7f5937357f64","The mediating role of Home Energy Management Systems","van Dam, S.S. (TU Delft OLD Housing Systems); Bakker, C.A. (TU Delft Design for Sustainability); van Hal, J.D.M. (TU Delft Sustainable Housing Transformation)","","2009","","","en","conference paper","","","","","","Accepted Author Manuscript","","","","","OLD Housing Systems","","",""
"uuid:e31660a7-9a1c-4d3c-a97b-1167848d02c4","http://resolver.tudelft.nl/uuid:e31660a7-9a1c-4d3c-a97b-1167848d02c4","Onderzoek naar zettingen in de gemeente Zevenaar","de Lange, Ger (Deltares); van der Velden, WHJ (Fugro); Kopinga, J (Alterra); Hanssen, R.F. (TU Delft Mathematical Geodesy and Positioning); Marinkovic, P (TU Delft Mathematical Geodesy & Positioning); Buma, J.T. (Deltares); Goorden, N (Deltares); Bakker, MAJ (Deltares)","","2009","","","nl","report","Deltares","","","","","","","","","","Mathematical Geodesy and Positioning","","",""
"uuid:d363df81-5e9a-4f4d-90c9-335096894fff","http://resolver.tudelft.nl/uuid:d363df81-5e9a-4f4d-90c9-335096894fff","Groundwater flow through anisotropic fault zones in multiaquifer systems","Anderson, E.I.; Bakker, M.","","2008","Vertical faults through the shallow crust are commonly believed to act as either barriers to horizontal groundwater flow normal to the fault, conduits to horizontal flow tangential to the fault, or a combination of both. In addition, enhanced vertical permeability has been identified as a common feature. We investigate the effects of vertical anisotropy of a fault zone on the distribution of hydraulic head within the fault, using an analytic solution. We conclude that anisotropy ratios greater than 100 result in nearly hydrostatic conditions within the fault zone, despite the existence of significant vertical flow rates. Under these conditions, the Dupuit approximation is adequate for predicting the flow from one side of the fault to the other. We then present explicit analytical solutions to problems of steady groundwater flow in a multiaquifer system cut by a single vertical fault. The fault is linear and of negligible width, is infinite in length, and acts as a conduit for vertical fluid flow. The fault may act as a leaky barrier to horizontal flow normal to the fault, as a conduit to horizontal flow tangential to the fault, or a combination of both. Examples are presented that highlight the effects of enhanced vertical permeability of a fault on aquifer interaction in a multiaquifer system. Particle tracking is used to investigate the effects of the fault on pathlines.","groundwater; faults; analytic","en","journal article","American Geophysical Union","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:5c1e3201-14fa-435b-bbfe-f96ad0eed04e","http://resolver.tudelft.nl/uuid:5c1e3201-14fa-435b-bbfe-f96ad0eed04e","Variatie van de zwevend stof kwaliteit in het stroomgebied van de Maas","Bakker, I.J.I.; Klaver, G.T.; Jansen, S.; Joziasse, J.; Van der Meulen, E.S.","","2008","Transport van verontreinigingen gebonden aan slib kan een belangrijk deel uitmaken van het totale transport van deze stoffen. Het kan hierbij gaan om grote hoeveelheden die bovendien grensoverschrijdend verplaatst kunnen worden, en grote ecologische effecten teweeg kunnen brengen. Voor een goede inschatting van (ecologische) effecten en van de effectiviteit van maatregelen, onder andere in het kader van de Kaderrichtlijn Water (KRW) is het dan ook essentieel om de bronnen en transportpaden te kennen en de processen te begrijpen. De variatie van de zwevend stof kwaliteit in het stroomgebied van de Maas is op twee manieren uitgewerkt. Daarvoor zijn twee verschillende datasets gebruikt. Ten eerste de data afkomstig van de Internationale Maascommissie (IMC), met gegevens van macroparameters (‘algemene’ variabelen) en verontreinigingen in totaal water van het gehele stroomgebied. De concentraties in totaal water zijn gebruikt als indicatie voor de gehalten in zwevend stof. Daarnaast is een dataset van Rijkswaterstaat in Nederland gebruikt met gegevens van algemene variabelen en verontreinigingen in zwevend stof van het Nederlandse deel van de Maas. De variatie van concentraties zware metalen, PCB’s en PAK in zwevend stof in de Maas in Nederland lijkt vooral te worden veroorzaakt door variatie in debiet. Voor de zware metalen is dit verband niet consistent. De gehalten PCB’s (en minder sterk, metalen) nemen over het algemeen af bij een verhoging van het debiet, terwijl een verhoging van het debiet bij PAK’s over het algemeen leidt tot een verlaging van de gehalten in zwevend stof. De sterke correlatie van PAK’s en in mindere mate PCB’s geeft aan dat de variatie van deze verontreinigingen sterk bepaald wordt door input van één of enkele duidelijke bronnen. Er is een duidelijke invloed van de zijrivier de Sambre geconstateerd op gehalte van PAK’s in totaal water, hieruit wordt geconcludeerd dat het gehalte PAK in zwevend stof in de Maas wordt beïnvloed door de Sambre. Mogelijk is langs de Sambre een gebied aanwezig dat periodiek overstroomt, waarbij met PAK verontreinigde grond wordt geërodeerd en via de Sambre naar de Maas wordt getransporteerd. Over het algemeen liggen de gehalten aan PAK en zware metalen in het zwevend stof nabij de monding van de Maas (meetstation Keizersveer) lager dan bij de grens met België (meetstation Eijsden). Dit kan veroorzaakt worden door verdunning of door sedimentatie van verontreinigd zwevend stof. De gehalten PCB-28 zijn bij Keizersveer hoger dan bij Eijsden. Dit duidt op een bron van PCB-28 tussen Eijsden en Keizersveer (input vanuit zijstroom of lozing). Voor PCB-153 en PCB-52 zijn de gehalten bij beide meetstations ongeveer gelijk.","Meuse; river; pollution; water; PCB-28; CT04.20; Waterkwaliteit en Clamiteiten; CT023.11; Zwevend slib en Waterkwaliteit; Delft Cluster","nl","report","Delft Cluster","","","","","","","","","","","","",""
"uuid:563ad303-48d6-4376-9973-6ed358aeccb3","http://resolver.tudelft.nl/uuid:563ad303-48d6-4376-9973-6ed358aeccb3","Sustainability within product portfolio management","Wever, R.; Boks, C.B.; Bakker, C.A.","","2008","On both a strategic level and a product level a lot is known on how to integrate sustainability aspects. On the intermediate level of product portfolio management this is not true. Here the strategic sustainability goals of a company need to be translated into products. A company wanting to innovate in a green way automatically has to make product portfolio decisions through the choice of where to start. Resources and time are always limited, so a company will want to utilize its R&D capacity most effectively. This process of prioritization has received little academic attention. This paper identifies the different decisions that companies can take related to product portfolios. Of those, the decisions that are ill-addressed by classical EcoDesign tools and methods (namely decisions relating to products already on the market, and the option to design ameliorative products) are elaborated. Finally, (adaptations of) tools are discussed to incorporate sustainability in the early stages of the New Product Development process.","","en","conference paper","","","","","","","","","Industrial Design Engineering","","","","",""
"uuid:2cb802e5-6163-4b6e-8c3e-0f3891eb5e03","http://resolver.tudelft.nl/uuid:2cb802e5-6163-4b6e-8c3e-0f3891eb5e03","Overzicht bronnen van verontreinigd slib en mogelijke transportpaden","Bakker, I.J.I.; Klaver, G.T.; Jansen, S.; Joziasse, J.","","2008","Transport van verontreinigingen via slibdeeltjes (vooral via gesuspendeerd materiaal, daarnaast ook via ‘bedload’) kan een belangrijk aandeel vormen in het totale transport van deze stoffen. Het kan hierbij gaan om grote hoeveelheden die bovendien grensoverschrijdend verplaatst worden, en grote ecologische effecten teweeg kunnen brengen. Voor een goede inschatting van effecten en maatregelen, onder andere in het licht van de Kaderrichtlijn Water (KRW, EU (2000)), is het dan ook essentieel om de bronnen, transportpaden en processen goed te kennen. Extreme gebeurtenissen zoals droogte en overstromingen, die door klimaatverandering in de nabije toekomst frequenter zullen voorkomen, hebben hier een grote invloed op. Werkpakket 3 van het Delft Cluster Project ‘Waterkwaliteit en Calamiteiten’ richt zich daarom op het transport van verontreinigingen via het slib en de invloed van extreme gebeurtenissen hierop. In dit rapport wordt een overzicht gegeven van informatie die aanwezig is over het transport van verontreinigingen via slib in de Rijn en Maas. Hierbij wordt gebruik gemaakt van waterbodem-, bodem- en waterkwaliteitsgegevens uit diverse nationale en internationale databases. Voor de Rijn wordt hierbij gebruik gemaakt van onderzoek dat in opdracht van het Havenbedrijf Rotterdam is uitgevoerd door Heise et al. (2004) naar het risico van het mobiliseren van verontreinigd sediment in het Duitse deel van het stroomgebied. Tevens wordt gebruik gemaakt van resultaten van aanvullende zwevend slib analyses en datasets voor de Nederlandse uiterwaarden. Voor de Maas wordt gebruik gemaakt van de ICM-database, en zijn gegevens via de Belgische onderzoekspartners binnen het EU-AquaTerraproject ontsloten. Andere bronnen van informatie zijn diverse dissertaties, waaronder Leenaers (1989), databases en rapportages van RIZA, onderzoek naar slibafzetting en –kwaliteit in Maas uiterwaarden (Hoogvliet en Rang, 2005), etc.","pollution; climatechange; drought; flood; water; Meuse; CT04.20; Waterkwaliteit en Calamiteiten; CT023.11; Zwevend slib en waterkwaliteit; Delft Cluster","nl","report","Delft Cluster","","","","","","","","","","","","",""
"uuid:eef11924-9c4a-49b4-9f94-971d3765796f","http://resolver.tudelft.nl/uuid:eef11924-9c4a-49b4-9f94-971d3765796f","Management of projects: A people process","Bakker, H.L.M.","","2008","","Intreerede","en","public lecture","","","","","","","","","Mechanical Maritime and Materials Engineering","","","","",""
"uuid:0f300125-019d-489f-a71e-80de7254c08e","http://resolver.tudelft.nl/uuid:0f300125-019d-489f-a71e-80de7254c08e","Calibration of transient groundwater models using time series analysis and moment matching","Bakker, M.; Maas, K.; Von Asmuth, J.R.","","2008","A comprehensive and efficient approach is presented for the calibration of transient groundwater models. The approach starts with the time series analysis of the measured heads in observation wells using all active stresses as input series, which may include rainfall, evaporation, surface water levels, and pumping. The time series analysis results in the impulse response function of each stress at the observation well. For each impulse response function, the temporal moments M0 and M1 may be computed. Both moments fulfill differential equations that are equivalent to the differential equation for steady groundwater flow, with known values along physical boundaries. The model of M0 may be calibrated for the transmissivity, as it does not depend on the storage coefficient; the computed values of M0 at the observation wells are used for calibration. The model of M1 may be calibrated for the storage coefficient, once the transmissivity is known from the M0 model; the computed values of M1 at the observation wells are used for calibration. The approach is intended for systems that may be approximated as linear. In summary, our proposed calibration process for transient models reduces to the calibration of only two steady models. Several examples are given to demonstrate the accuracy and efficiency of the proposed approach.","transient groundwater modeling; calibration; time series modeling","en","journal article","American Geophysical Union","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:e6424d27-4e04-494c-8468-3d5c442bcb67","http://resolver.tudelft.nl/uuid:e6424d27-4e04-494c-8468-3d5c442bcb67","Ten Years of bored tunnels in the Netherlands: Part I: Geotechnical issues","Bakker, K.J.; Bezuijen, A.","","2008","Ten years have passed since in 1997 for the first time construction of bored tunnels in the Netherlands soft soil was undertaken. Before that date essentially only immersed tunnels and cut-and-cover tunnels were constructed in the Netherlands. The first two bored tunnels were Pilot Projects, the 2nd Heinenoord tunnel and the Botlek Rail tunnel. Since then a series of other bored tunnels has been constructed and some are still under construction today. At the beginning of this period, amongst others Bakker et al(1997), gave an overview of the risks related to bored tunnels in soft ground and a plan for research related to the pilot projects was developed. After that in 1999 the 2nd Heinenoord tunnel opened for the public, the “Jointed platform for Bored tunnelling”, in short GPB, was organized, to coordinate further research and monitoring of bored tunnels. This platform is supervised by the Center for Underground Construction. In this paper a summary is given of some of the most characteristic observations on these 10 years of underground construction in the Netherlands. In the first part of this paper the focus is on geotechnical interactions, and stability, whereas part two will focus more on structural related issues.","bored; tunnels; geotechnics; monitoring","en","conference paper","CRC Press","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:0502075a-0ac6-4362-849b-1c858aae8981","http://resolver.tudelft.nl/uuid:0502075a-0ac6-4362-849b-1c858aae8981","Ten years of bored tunnels in the Netherlands: Part II: Structural issues","Bakker, K.J.; Bezuijen, A.","","2008","In 1997 for the first time construction of bored tunnels in the Netherlands soft soil was undertaken. Before that date essentially only immersed tunnels and cut-and-cover tunnels were constructed in the Netherlands. The first two bored tunnels were Pilot Projects, the 2nd Heinenoord tunnel and the Botlek Rail tunnel. Since then a series of other bored tunnels has been constructed and some are still under construction today. At the beginning of this period, amongst others Bakker (1997), gave an overview of the risks related to bored tunnels in soft ground and explained about a plan for research related to the Pilot projects. Ten years have passed, a lot of monitoring and research has been done. In this paper that is split in two parts a summary is given of some of the most characteristic observations of these past 10 years of underground construction in the Netherlands. In this second part, the emphasis will be on structural related issues discussed whereas in part one, frontal stability, grouting and soil deformations are discussed.","","en","conference paper","CRC Press","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:9486aad5-6a15-49a2-bcf4-b8bec88d654d","http://resolver.tudelft.nl/uuid:9486aad5-6a15-49a2-bcf4-b8bec88d654d","Standaard werkplek als leidraad voor flexibiliteit","Bakker, I.C. (TU Delft Real Estate Management); van der Voordt, Theo (TU Delft Real Estate Management)","","2008","Met het ‘Programma vernieuwing Rijksdienst’ geeft het kabinet invulling aan de doelstelling om een efficiëntere Rijksdienst te realiseren. In het kader hiervan wordt de Rijkswerkplek ingevoerd; een standaard en up to date werkplek waar elke rijksambtenaar gebruik van kan maken.","","nl","journal article","","","","","","","","","","","Real Estate Management","","",""
"uuid:a774c304-39a2-4306-af82-7588821f772a","http://resolver.tudelft.nl/uuid:a774c304-39a2-4306-af82-7588821f772a","Old contaminated sediments in the Rhine basin during extreme situations","Peñailillo Burgos, R.; Passier, H.; Bakker, I.; Delsman, J.; Van Vliet, M.","","2007","Sediments play an important role in water resources management. In the past, hazardous contaminants from municipal and industrial wastewater effluents and from agriculture were discharged in large quantities into the water bodies and accumulated within the bottom sediments. Today, relatively unpolluted recent sediment surface layers cover older contaminated sediments. Due to increasing water discharges associated with high precipitation and heavy rainfall events (climate change) and land use changes there is an increasing risk of the resuspension of old contaminated sediment layers and the transport of the particle-bound pollutants downstream in river systems over long. In this study we focus on the potential release of the old contaminated sediments in the Rhine basin during extremely high discharges and low flows. The main aims of this study are to make an overview of the relevant knowledge gaps and to identify advisable research directions on the basis of existing information (data) and models. The main conclusion of this study is that insight is missing in the expected remobilisation and recontamination levels of contaminated sediments during extreme situations. The focus not only has to go on the historical contamination but also on the present-day contaminations, and on the identification of actual and potential problems. Better sediment and water quality measurements (e.g. one hour samples during flooding events) and models (source location) will allow us to get a better understanding of the sediment dynamics in the Rhine basin during extreme situations. This will give us a deeper insight in the substance interactions with sediment and in the water column (geometry of the pollutants).","old contaminated sediments; Rhine; altlasten; extreme situations; floods; droughts; CT04.20; Waterkwaliteit en Calamiteiten; CT04.23.11; Zwevend slib en waterkwaliteit; Delft Cluster","en","report","Delft Cluster","","","","","","","","","","","","",""
"uuid:87ac7063-88c8-4c8e-be69-a54505eb3678","http://resolver.tudelft.nl/uuid:87ac7063-88c8-4c8e-be69-a54505eb3678","The fluxes through glycolytic enzymes in Saccharomyces cerevisiae are predominantly regulated at posttranscriptional levels","Daran, J.M.; Bakker, B.M.; Pronk, J.T.; Westerhoff, H.V.; De Winde, J.H.; Heck, A.J.R.; Slijper, M.; De Groot, M.J.L.; Luttik, M.A.H.; Van Gulik, W.M.; Rossell, S.; Daran-Lapujade, P.","","2007","Metabolic fluxes may be regulated ‘‘hierarchically,’’ e.g., by changes of gene expression that adjust enzyme capacities (Vmax) and/or ‘‘metabolically’’ by interactions of enzymes with substrates, products, or allosteric effectors. In the present study, a method is developed to dissect the hierarchical regulation into contributions by transcription, translation, protein degradation, and posttranslational modification. The method was applied to the regulation of fluxes through individual glycolytic enzymes when the yeast Saccharomyces cerevisiae was confronted with the absence of oxygen and the presence of benzoic acid depleting its ATP. Metabolic regulation largely contributed to the10-fold change in flux through the glycolytic enzymes. This contribution varied from 50 to 80%, depending on the glycolytic step and the cultivation condition tested. Within the 50–20% hierarchical regulation of fluxes, transcription played a minor role, whereas regulation of protein synthesis or degradation was the most important. These also contributed to 75–100% of the regulation of protein levels.","Open Access","en","journal article","National Academy of Sciences","","","","","","","","Applied Sciences","Biotechnology","","","",""
"uuid:048cb071-3f03-484b-a20d-c688e23067a8","http://resolver.tudelft.nl/uuid:048cb071-3f03-484b-a20d-c688e23067a8","Learning to simulate and predict chaotic dynamical systems","Bakker, R.","Van den Bleek, C.M. (promotor); Schouten, J.C. (promotor)","2007","With precise knowledge of the rules which govern a deterministic chaotic system, it is possible to interact with the system and change its dynamics. This research is part of a larger project, in which chaos control is used to improve the bubbling behavior of multi-phase chemical reactors. Chaos control requires models which capture the complete behavior of the system. If we replace the system by its model, or vice versa, we should not notice a change in dynamical behavior. We restrict ourselves to data-driven models, which learn both their structure and parameters from measured data. In cooperation with Robert Jan de Korte [1], we use a neural network model to control the chaotic dynamics of an experimental, driven and damped pendulum. The neural network provides a nearly perfect model for this system. The gas-solids fluidized bed is a much more difficult system, because it has a large number of state variables, while the pendulum has only three. To get a good predictive model, the neural network approach is improved with several enhancements: (1) Inputs are compressed by weighted Principal Component Analysis. (2) An 'error propagation"" scheme is introduced, in the which the model synchronizes itself with the data. (3) The neural network is connected in parallel to a linear predictive model. (4) A new pruning algorithm removes unused nodes from the network. (5) A statistical test by Diks et. al. [3] compares the chaotic attractors of the model-generated and measured time series. The approach is succesfully applied to benchmark tests. But Diks' test reveals that during training, the correctness of the model's attractor jumps from right to wrong from one iteration to another. We investigate why this is, and present an example of a model which can predict the measured data with zero error, but yet has a very different attractor. This has far-reaching consequences. It turns out that the learning of an attractor from measured data is a very ill-posed problem, in which the data covers all available dimensions globally, but locally the data is confined to low-dimensional structures. When a global nonlinear model is trained on this data, it locally has too many degrees of freedom, and this leads to arbitrary dynamics. A Nonlinear Principal Component Regression (NLPCR) algorithm is needed, which locally detects and eliminates the unused dimensions. We develop the 'Split & Fit' (S&F) algorithm, based on a fuzzy partitioning of the input space. In each region, unused dimensions are detected with Principal Component Analysis (PCA). This algorithm is shown to keep an otherwise unstable model for a chaotic laser onto the desired trajectory. Meanwhile, Robert Jan de Korte found that deterministic prediction of gas-solids fluidized beds is not feasible. But the S&F algorithm does learn the attractor of another experimental reactor, a gas-liquid bubble column with a single train of rising bubbles [2]. The S&F model paves the way for robust learning of chaotic attractors. However, real-world systems rarely meet the requirement of determinism and low-dimensionality. For these systems, we recommend to develop algorithms which find structure in 'noisy' nonlinear behavior. A good starting point is to have a probabilistic representation (kernel smoother or mixture density) of how the measured data are distributed in state space. [1] R.J. De Korte (2000), ""Controlling the Chaotic Hydrodynamics of Fluidized Beds"", PhD thesis, Delft Unversity of Technology [2] S. Kaart (2002), ""Controlling Chaotic Bubbles"", PhD thesis, Delft Unversity of Technology [3] C. Diks, W.R. van Zwet, F. Takens, J. de Goede (1996), ""Detecting differences between delay vector distributions, pp. 2169--2176","deterministic chaos; time-series; dynamical system; chaotic attractor; multi-phase reactor; fluidized bed; chaos control; pendulum; bubble column","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:8d3d11ea-dcfd-4a4e-87c5-77472c5e880f","http://resolver.tudelft.nl/uuid:8d3d11ea-dcfd-4a4e-87c5-77472c5e880f","The composition of suspended particulate matter during floodings of the river Meuse","Bakker, I.","","2007","Since the Industrial Revolution, mankind has disturbed the natural functioning of river floodplains by a high input of contaminants in the environment. Riverine suspended matter is the most important source for elevated levels of contaminants in floodplain areas. Previous research mainly focused on processes affecting the distribution of contaminants on the floodplain areas themselves, while the influence of the ultimate polluting source, river suspended matter, is poorly understood. Only minor knowledge is available on the temporal and spatial variability of contaminants in suspended matter. This research focuses on the variability in contamination degree of both suspended matter and floodplain sediment for the Dutch part of the river Meuse.","floodplain; contamination; Meuse; river; sediment; flooding; Delft Cluster","en","report","Delft Cluster","","","","","","","","","","","","",""
"uuid:d0dfb5f1-7b24-412a-bcfb-2b98a98f5785","http://resolver.tudelft.nl/uuid:d0dfb5f1-7b24-412a-bcfb-2b98a98f5785","Analytical solutions for whirling groundwater flow in two-dimensional heterogeneous anisotropic aquifers","Hemker, K.; Bakker, M.","","2006","Analytical solutions are derived for steady state groundwater flow in a heterogeneous, anisotropic, semiconfined aquifer. The aquifer consists of a number of horizontal layers, while each layer consists of a number of homogeneous cells with different hydraulic conductivity tensors. An exact solution for an arbitrary number of layers and cells is derived using a multilayer approach. Hypothetical models are used to study how flow is affected by heterogeneity in the anisotropy. When the major principal direction of the transmissivity tensor varies between layers, streamlines have the shape of spirals. Bundles of spiraling streamlines rotating in the same direction are called “groundwater whirls.” Analytical and numerical models of hypothetical cases produce the same flow patterns of groundwater whirls. Projected streamlines may be represented by stream function contours, which allows for easy interpretation of the main characteristics of complex whirl patterns. Typical whirl patterns may be identified in relatively simple models. Clockwise and counterclockwise whirl axes occur at the interfaces of adjacent layers. One or more clockwise whirls may occur within one counterclockwise whirl, and vice versa. The practical consequence of groundwater whirls is that the exchange of water between aquifer layers is intensified. This may have a significant impact on contaminant spreading.","analytical solution; layered aquifer; heterogeneity; anisotropy; streamlines; stream function","en","journal article","American Geophysical Union","","","","","","","","Civil Engineering and Geosciences","Water Management","","","",""
"uuid:3227d30a-4672-4ed9-9e62-0a85f14b1e39","http://resolver.tudelft.nl/uuid:3227d30a-4672-4ed9-9e62-0a85f14b1e39","Lanthanide-Loaded Liposomes for Multimodality Imaging and Therapy","Zielhuis, S.W.; Seppenwoolde, J.H.; Mateus, V.A.P.; Bakker, C.J.G.; Krijger, G.C.; Storm, G.; Zonnenberg, B.A.; Van het Schip, A.D.; Koning, G.A.; Nijsen, J.F.W.","","2006","Many advanced molecular imaging agents are currently being investigated preclinically. Especially, liposomes, have proven to be very promising carrier systems for diagnostic agents for use in single-photon emission computed tomography (SPECT) or magnetic resonance imaging (MRI), as well as for therapeutic agents to treat diseases such as cancer. In this study, nanosized liposomes were designed and labeled with the radionuclides, holmium-166 (both a beta- and gamma-emitter and also highly paramagnetic) or technetium-99m, and coloaded with paramagnetic gadolinium allowing multimodality SPECT and MR imaging and radionuclide therapy with one single agent. Methods: Diethylenetriaminepentaacetic acid bisoctadecylamide (an amphiphilic molecule with a chelating group suitable for labeling with radionuclides) and gadoliniumacetylacetonate (GdAcAc) (a small lipophilic paramagnetic molecule) were incorporated in liposomes. The liposomes were characterized by measuring their mean size and size distribution, gadolinium content, and radiochemical stability after incubation in human serum at 37°C. The MRI properties (in vitro) were determined by use of relaxivity measurements at 1.5 and 3.0 Tesla in order to evaluate their potency as imaging agents. Results: The liposomes were successfully labeled with holmium-166, resulting in a high labeling efficiency (95% ± 1%) and radiochemical stability (> 98% after 48 hours of incubation), and coloaded with GdAcAc. Labeling of liposomes with technetium-99m was somewhat less efficient (85% ± 2%), although their radiochemical stability was sufficient (95% ± 1% after 6 hours of incubation). MRI measurements showed that the incorporation of GdAcAc had a strong effect on the MRI relaxivity. Conclusions: The synthesized liposomes allow for multimodality imaging and therapy, which makes these new agents highly attractive for future applications","liposomes; molecular imaging; MRI; gadolinium; holmium; SPECT; technetium","en","journal article","Mary Ann Liebert","","","","","","","","Applied Sciences","Radiation, Radionuclides and Reactors","","","",""
"uuid:3a36b2bf-b976-414d-8592-e44567940a67","http://resolver.tudelft.nl/uuid:3a36b2bf-b976-414d-8592-e44567940a67","Influence of pump wavelength and crystal length on the phase matching of optical rectification","Van der Valk, N.C.J.; Planken, P.C.M.; Buijserd, A.N.; Bakker, H.J.","","2005","We present measurements on terahertz generation by optical rectification, in which both the thickness of the generation crystal and the wavelength of the generating optical pulse are varied. The difference between the group velocity at optical frequencies and the phase velocity at terahertz frequencies affects the time trace and spectrum of the generated terahertz pulse. For the thickest crystal, we find that the phase mismatch gives rise to the generation of two pulses, separated by 4.5 ps. The physical origin of the observed features is clarified with a simple model that includes phase matching and absorption.","ultrafast nonlinear optics; spectroscopy; far infrared","en","journal article","Optical Society of America","","","","","","","","Applied Sciences","Imaging Science and Technology","","","",""
"uuid:d3f9985e-e11e-4222-8427-1306e1af171c","http://resolver.tudelft.nl/uuid:d3f9985e-e11e-4222-8427-1306e1af171c","Streamline topologies near a non-simple degenerate critical point close to a stationary wall using normal forms","Gürcan, F.; Deliceoglu, A.; Bakker, P.G.","","2005","","","en","journal article","Cambridge University Press","","","","","","","","","","","","",""
"uuid:94c3190a-dfdb-4e53-bf15-b1a9ad2536d2","http://resolver.tudelft.nl/uuid:94c3190a-dfdb-4e53-bf15-b1a9ad2536d2","A CMOS smart temperature sensor with a 3 sigm Inaccuracy of +-0.5 deg C from -50 deg C to 120 deg C","Pertijs, M.A.P.; Niederkorn, A.; McKillop, B.; Bakker, A.; Huijsing, J.H.","","2005","","","en","journal article","IEEE","","","","","","","","","","","","",""
"uuid:168206a4-04fc-4420-9432-3979dec11633","http://resolver.tudelft.nl/uuid:168206a4-04fc-4420-9432-3979dec11633","Apparatus and method of navigating an instrument","Bakker, N.H.; Den Heeten, G.J.","","2004","An apparatus to be used with navigating an instrument in a vascular tree of a patient, comprises a patient's examination table, a C-arm, mounted to which is an X-ray source and an image recorder for registering first X-ray images of the patient, obtained by the use of the X-ray source, and a processing unit connected with the image recorder for processing the images of the first images registered by the image recorder, as well as a monitor optionally connectable with the processing unit for displaying the image, wherein the processing unit is designed for combining the first X-ray images of the patient with second image data relating to at least a portion of the patient's vascular tree, wherein the processing unit is designed for, with respect to an adjustable projection orientation,; deriving a two-dimensional projection image from threedimensional image data concerning the vascular tree of the patient, wherein the projection orientation depends on the information regarding the situation and/or position of the patient's examination table and/or the C-arm","","en","patent","European Patent Office","","","","","","","","Mechanical, Maritime and Materials Engineering","","","","",""
"uuid:7e1f4283-2f36-4fd9-96a3-659dd6956947","http://resolver.tudelft.nl/uuid:7e1f4283-2f36-4fd9-96a3-659dd6956947","The influence of time-dependent hydrodynamics on polymer centre-of-mass motion","Lowe, C.P.; Bakker, A.F.; Dreischor, M.W.","","2004","We describe simulations of isolated ideal polymer chains consisting of N monomers. The solvent is simulated using a dissipative ideal gas maintained at a set temperature by a Lowe-Andersen thermostat. By choosing a particular ratio of the Kuhn length to the monomer hydrodynamic radius, long-polymer scaling of the diffusion coefficient holds even for chains composed of a few beads. However, this requires that the model capture the hydrodynamics correctly on length scales equivalent to a typical solvent particle separation. It does. The decay of the centre-of-mass velocity autocorrelation function, C(t), for short chains scales rapidly to a function independent of N, so we can determine the long-polymer limit of the function. At long times it decays with an algebraic long-time tail of the form C(t) ?t?3/2. This is consistent with the predictions of theories that take into account the time dependence of the intra-polymer hydrodynamic interactions. We argue that the scaling of the decay implies that the intra-polymer hydrodynamic interactions propagate on a surprisingly rapid time scale.","","en","journal article","EDP Sciences; IOP publishing","","","","","","","","Applied Sciences","","","","",""
"uuid:92e4bf81-d12f-4c77-804e-94655a271b2c","http://resolver.tudelft.nl/uuid:92e4bf81-d12f-4c77-804e-94655a271b2c","Report of meeting on measurement of suspended solids in the Meuse","Joziasse, J.; Klaver, G.; Bakker, I.","","2004","On June 19/20, 2007 a visit was paid to a suspended particulate matter (SPM) sampling and monitoring site in the Ourthe river (Liège region), between the confluence with the Vesdre river and the mouth of the Ourthe in the Meuse river. The next day, a workshop was organised in which backgrounds, methods and procedures for SPM sampling and monitoring were discussed. Results of measuring SPM quantity and quality in the Meuse river basin were presented. The discussions were focused on the implementation of this matrix in WFD instigated monitoring programs. The workshop was very successful, with animated discussions.","Meuse; Ourthe; SPM; centrifuge; suspended solids; hydropower; CT04.20; Waterkwaliteit en Calamiteiten; CT04.23.11; Zwevend slib en waterkwaliteit; Delft Cluster","en","report","Delft Cluster","","","","","","","","","","","","",""
"uuid:5f5b88a6-d7fe-486e-bed1-210e75431256","http://resolver.tudelft.nl/uuid:5f5b88a6-d7fe-486e-bed1-210e75431256","A guidewire for guiding a catheter","Bakker, N.H.","","2003","The invention relates to a guidewire suitable for guiding a catheter into an occluded blood vessel, comprising a torsionally rigid shaft having a proximal end and a distal end, and on the distal end of the shaft there is an elongated flexible body, designed to follow the course of the blood vessel, which body retains its shape when during use the guidewire is subjected to a pushing load, wherein the distally oriented head of the flexible body is provided with a flexible trailer wire, which during use follows the flow in the blood vessel.","","en","patent","European Patent Office","","","","","","","","Mechanical, Maritime and Materials Engineering","","","","",""
"uuid:7d64e741-a83a-4c4d-80d3-5e5f82504e67","http://resolver.tudelft.nl/uuid:7d64e741-a83a-4c4d-80d3-5e5f82504e67","Structural Design of Linings for Bored Tunnels in Soft Ground","Bakker, K.J.","","2003","The increase of bored tunnels in the Netherlands has raised the question how to design the tunnel structure in an efficient way. As a large part of the cost of a bore tunnel is related to the cost of the lining, it is important to design the lining in a cost-effective way. In the Netherlands it is customary to base the structural design of tunnel linings, on the use of models, validated models. Due to the increased flexibility in modelling quite often in engineering practice these models are numerical. Numerical models however are sometimes difficult to interpret, this contrary to the clarity of most empirical and analytical models. In this paper a number of, these simple models are used to evaluate different design aspects of the tunnel lining. These models are discussed in a comparison with measurements and results of more elaborate numerical analysis. The purpose of which is to show that tunnel lining behaviour can be understood, with relatively simple models. The advantage of simple models is that these can be used for a 1st order covering of the dominant mechanisms and for preliminary design. Empirical relations and analytical solutions generally give a good insight in the relevant issues. However to take into account the complexity of geometry, geology and construction method, in practice for a final design numerical models are necessary. Finally, a number of special issues, such as 3D effects, creep and longitudinal effects in the tunnel tube, and in addition to that, the effects of fire as well as some aspects of durability, are discussed.","","en","journal article","Delft University of Technology","","","","","","","","Civil Engineering and Geosciences","","","","",""
"uuid:fbc554ac-48e5-44c6-aa9d-f87cf0d1e168","http://resolver.tudelft.nl/uuid:fbc554ac-48e5-44c6-aa9d-f87cf0d1e168","Ultrasonic Underside Inspection for Fatigue Cracks in the Deck Plate of a Steel Orthotropic Bridge Deck","Bakker, M.C.M.; De Jong, F.B.P.","","2003","Due to an unexpected increase of heavy traffic large fatigue cracks appeared through the deck plate of orthotropic steel bridge decks in the Netherlands. Visual inspection revealed that this particular type of crack initiates where a weld joins the deck plate, a rib and a girder. These critical points are commonly inspected from the roadside, which necessitates that the road is closed down for all traffic and that the wear layer is first removed. To overcome these costly drawbacks a new method is proposed that enables ultrasonic inspection of the deck plate from the underside of the bridge deck. The method requires a combination of two special measurement techniques, which are optimised for the bridge problem at hand. To detect the maximum crack depth an angled pitch-catch technique is employed. The crack length can be detected along the rib weld by employing the simpler pulse-echo technique. The crack depth and crack length are determined from the respective ultrasonic data sets by a calibration, which relates the number of detected waves to the actual crack size. The calibration is determined by ultrasonically monitoring the various crack stages during a fatigue test that is conducted on a bridge deck specimen. The original, uncracked state and the final state where the cracks can be visibly detected in the deck plate determine the extremes. The tests show that a reasonable accurate detection of crack size is quite possible, while the visual inspections prove to be useless until the crack has already grown completely through the deck plate. The new method provides a crack depth and crack length estimate with an accuracy of ±15 %.","","en","journal article","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:5e884eaf-710b-4995-86ea-f3e9f6caf062","http://resolver.tudelft.nl/uuid:5e884eaf-710b-4995-86ea-f3e9f6caf062","Structural design of linings for bored tunnels in soft ground","Bakker, K.J.","","2003","","underground; tunnels; soft ground models","en","journal article","","","","","","","","","","","","","",""
"uuid:51bf8ac0-43fe-4238-9f34-a0533d10673f","http://resolver.tudelft.nl/uuid:51bf8ac0-43fe-4238-9f34-a0533d10673f","Current-induced transition in atomic-sized contacts of metallic alloys","Heemskerk, J.W.T; Noat, Y.; Bakker, D.J.; van Ruitenbeek, J.M.; Thijsse, B.J.; Klaver, P.","","2003","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:f3f60507-5b08-43cb-a309-c3446c972395","http://resolver.tudelft.nl/uuid:f3f60507-5b08-43cb-a309-c3446c972395","Image structure analysis for seismic interpretation","Bakker, P.","Van Vliet, L.J. (promotor)","2002","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:e89f4ec2-cd1e-44f9-a21a-7d5bb68aa4d8","http://resolver.tudelft.nl/uuid:e89f4ec2-cd1e-44f9-a21a-7d5bb68aa4d8","The role of sound propagation in concentrated colloidal suspensions","Bakker, A.F.; Lowe, C.P.","","2002","In a suspension, the hydrodynamic interactions between particles can propagate by two mechanisms: relatively slowly, by the diffusion of transverse momentum, or relatively rapidly, by the propagation of sound waves. Here we describe computer simulation results for the collective and single particle dynamics of colloidal particles with the aim of clarifying the role of sound. We find that for single particle motion the effect is rather trivial. As for an isolated particle, compressibility modifies the decay of velocity fluctuations only at very short times. For collective correlations this is not true. Our results show that the multiple scattering of sound waves between particles can induce correlated collective motions on time scales comparable with the diffusion of transverse momentum. The effects of compressibility are no longer restricted to very short times and manifest themselves as rapid oscillations in the time dependence of the collective diffusion coefficient. We suggest that these oscillations can largely be explained in terms of “effective” incompressible hydrodynamic theory, the suspension bulk viscosity, kinematic viscosity, and speed of sound becoming the relevant parameters. The oscillations are furthermore centered on the (hypothetical) incompressible result. Thus, while the effects of sound propagation may extend to surprisingly long times, the net effect remains limited to very short times. We discuss where these sound-induced oscillations will be relevant experimentally.","colloids; suspensions; hydrodynamics; acoustic wave propagation; acoustic wave scattering; fluctuations; compressibility; viscosity","en","journal article","American Institute of Physics","","","","","","","","Applied Sciences","Computational Physics","","","",""
"uuid:41461a68-5abf-49d0-8443-529533848430","http://resolver.tudelft.nl/uuid:41461a68-5abf-49d0-8443-529533848430","Metabolic Engineering of Glycerol Production in Saccharomyces cerevisiae","Overkamp, K.M.; Bakker, B.M.; Kotter, P.; Luttik, M.A.; Van Dijken, J.P.; Pronk, J.T.","","2002","","","en","journal article","American Society for Microbiology","","","","","","","","","","","","",""
"uuid:fbdc5fd5-ca6d-483c-83ec-65aabb40398e","http://resolver.tudelft.nl/uuid:fbdc5fd5-ca6d-483c-83ec-65aabb40398e","Spatial Orientation in Virtual Environments","Bakker, N.H.","Stassen, H.G. (promotor)","2001","Recently, a growing interest can be detected in the application of Virtual Environment (VE) technology as an operator interface. VEs are three-dimensional computer-generated images that can be shown on a conventional monitor, on a large screen display, or on a head-mounted display. In order to use these three-dimensional interfaces for finding and retrieving information, the user must be able to spatially orient themselves. Different types of VE technology are available for navigating in these VEs, and different types of navigation can be enabled. A choice has to be made between the different options to enable good spatial orientation of the user. There are two main types of VE interfaces: an immersive interface that provides rich sensory feedback to the user when moving around in the VE, and a non-immersive interface that provides only visual feedback to the user when moving around in the VE. Furthermore, navigation through the VE can either be continuous providing fluent motion, or can be discontinuous which means that the viewpoint is displaced instantaneously over a large distance. To provide insight into the possible effects of these options a series of nine experiments was carried out. In the experiments the quality of spatial orientation behaviour of test subjects is measured while using the different types of interface and the different types of navigation. The results of the experiments indicate that immersive navigation improves the perception of displacement through the VE, which in turn aids the acquisition of spatial knowledge. However, as soon as the spatial layout of the VE is learned the two types of navigation interface do not lead to differences in spatial orientation performance. A discontinuous displacement leads to temporary disorientation, which will hinder the acquisition of spatial knowledge. The type of discontinuous displacements has an effect on the time needed for anticipation. The disorienting effects of a discontinuous displacement can be compensated for by enabling cognitive anticipation to the destination of the displacement. These results suggest that immersive navigation might only be beneficial for application domains in which new spatial layouts have to be learned every time or in domains where the primary users are novices. For instance, in training firemen to teach them the layout of new buildings with VE, or in using architectural walkthroughs in VE to show new building designs to potential buyers. Discontinuous movement should not be allowed when exploring a new environment. Once the environment is learned and if fast displacement is essential then discontinuous displacement should be preferred. In this case, the interface designer must make sure that information is provided about the destination of a discontinuous displacement.","virtual environment technology; VE technology; operator interface; information retrieval","en","doctoral thesis","Delft University Press","","","","","","","","Design, Engineering and Production","","","","",""
"uuid:53830f57-5c5f-4dcb-a654-e93e33b8be1d","http://resolver.tudelft.nl/uuid:53830f57-5c5f-4dcb-a654-e93e33b8be1d","Confidence and curvature estimation of curvilinear structures in 3-D","Bakker, P.; Van Vliet, L.P.; Verbeek, P.W.","","2001","","","en","conference paper","IEEE","","","","","","","","Applied Sciences","","","","",""
"uuid:eeac18f3-3384-4b34-af28-4cd6478a64ba","http://resolver.tudelft.nl/uuid:eeac18f3-3384-4b34-af28-4cd6478a64ba","Analysis and detection of 3-D curvilinear structures","Bakker, P.; Van Vliet, L.J.; Verbeek, P.W.","","2001","","","en","conference paper","ASCI","","","","","","","","Applied Sciences","","","","",""
"uuid:21780687-dcd6-4f78-8df8-1d7d0309f8a7","http://resolver.tudelft.nl/uuid:21780687-dcd6-4f78-8df8-1d7d0309f8a7","The immobilisation of Metallo-enzymes and their application in non-natural conversions","Bakker, M.","Sheldon, R.A. (promotor)","2000","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:edbaa896-e24e-4577-b013-8d057fec0f01","http://resolver.tudelft.nl/uuid:edbaa896-e24e-4577-b013-8d057fec0f01","Soil Retaining Structures: Development of models for structural analysis","Bakker, K.J.","Verruijt, A. (promotor); Vrijling, J.K. (promotor)","2000","The topic of this thesis is the development of models for the structural analysis of soil retaining structures. The soil retaining structures being looked at are; block revetments, flexible retaining walls and bored tunnels in soft soil. Within this context typical structural behavior of these structures is discussed too. The emphasis within the context of model development is on the use of Finite Element analysis as a generic toolbox for model development. In chapter 3 a methodology for the development of models is formulated. Both verification, the testing of the integrity of a model and the relation with models of lower hierarchy, and evaluation, testing the accuracy of a model are important. Accuracy and uncertainty are related aspects of model development. In chapter 4 an analytical toolbox for the development of models for structural analysis is given. One of the observations in the formulation of this chapter was that groundwater flow can be evaluated based on the same principle as equilibrium of stresses; the principle of virtual work. In the next three chapters 5, 6, and 7 three examples are given of development of models for the structural analysis of soil retaining structures. In chapter 5, a model for the stability against sliding of the top-layer of a revetment is put forward. The model is evaluated against prototype information. The validity to use Delta flume measurements to validate models for the design of a revetments cover-layer is being reconsidered, as there is reason to believe that the undrained response which is attributing to'the strength of a cover-layer has 3 dimensional effects being overlooked in a 2D measurement. In chapter 6, the models for sheet-pile retaining walls are described. The development of finite element analysis for sheet pile walls is described. Subsequently some of the verification analyses are described including an analytical solution derived from plasticity theory. Finally the finite element model is validated against prototype measurements, i.e. the Karlsruhe sheet pile test (1993). Within this context the test is evaluated applying inverse analysis. One of the conclusions was that a distinct difference between the in-situ stiffness of a sand layer and the stiffness as derived from a laboratory test was found. The reason for this is thought to be the breaking up of structure during sampling in advance of the laboratory testing. This structure is not recovered during preparation in the laboratory. The model evaluation indicates that the application of Finite Element analysis improves the accuracy in comparison to the empirical models. In chapter 7, the structural models for the design of a tunnel liner are discussed. The problems related to bored tunnelling in soft soil are discussed. The model hierarchy for the evaluation of the tunnel liner is discussed. In the second part of this chapter, a back-analysis of the measurements from the Second Heinenoord tunnel, with a finite element model is described. From this it comes forward that the uncertainty with respect to tunnel liner design is mainly related to the construction phase, i.e. tunnel ring assembly. In comparison to sheet pile walls, the soil loading of tunnel liners are easier to model.","finite element; PLAXIS; soil mechanics; bored tunnels","en","doctoral thesis","Balkema, Rotterdam","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:fd398056-48dd-4d84-8ae8-27a1b011d2c3","http://resolver.tudelft.nl/uuid:fd398056-48dd-4d84-8ae8-27a1b011d2c3","High-Accuracy CMOS Smart Temperature Sensors","Bakker, A.","Huijsing, J.H. (promotor)","2000","","Smart Sensors; Solid-State Circuits; Temperature Sensors; Sensor Interfaces; Analog Electronics","en","doctoral thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","","","","",""
"uuid:e0e11a4c-b8ff-4356-8bfa-5e3459b81a4a","http://resolver.tudelft.nl/uuid:e0e11a4c-b8ff-4356-8bfa-5e3459b81a4a","Non-Destructive Inspection Techniques based on Elastodynamics: Development and Validation","Bakker, M.C.M.","Vrouwenvelder, A.C.W.M. (promotor)","2000","","Ultrasonic NDT; integral transformations; transducer model; MTOFT","en","doctoral thesis","","","","","","","","","Civil Engineering and Geosciences","","","","",""
"uuid:a60150c9-2551-4b07-81b3-daa0c6abbf39","http://resolver.tudelft.nl/uuid:a60150c9-2551-4b07-81b3-daa0c6abbf39","Geboorde en gezonken tunnels","Vrijling, J.K.; Bakker, K.J.; Bezuyen, K.G.; Tan, G.L.","","2000","","","nl","lecture notes","TU Delft, Department Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:fbd1ebb3-0ecf-4a41-8e3d-7abf53633701","http://resolver.tudelft.nl/uuid:fbd1ebb3-0ecf-4a41-8e3d-7abf53633701","The Mitochondrial Alcohol Dehydrogenase Adh3p Is Involved in a Redox Shuttle in Saccharomyces cerevisiae","Bakker, B.M.; Bro, C.; Kotter, P.; Luttik, M.A.; van Dijken, J.P.; Pronk, J.T.","","2000","","","en","journal article","American Society for Microbiology","","","","","","","","","","","","",""
"uuid:f766100c-2992-42fa-a3b7-93043dc84687","http://resolver.tudelft.nl/uuid:f766100c-2992-42fa-a3b7-93043dc84687","In Vivo Analysis of the Mechanisms for Oxidation of Cytosolic NADH by Saccharomyces cerevisiae Mitochondria","Overkamp, K.M.; Bakker, B.M.; Kotter, P.; van Tuijl, A.; de Vries, S.; van Dijken, J.P.; Pronk, J.T.","","2000","","","en","journal article","American Society for Microbiology","","","","","","","","","","","","",""
"uuid:67eb1cc0-fd0f-443f-87a4-96e59c114af5","http://resolver.tudelft.nl/uuid:67eb1cc0-fd0f-443f-87a4-96e59c114af5","Softening in the blast furnace process: Local melt formation as the trigger for softening of ironbearing burden materials","Bakker, T.","Heerema, R.H. (promotor)","1999","","iron-metallurgy; blast furnace process; softening-melting; solidus relations","en","doctoral thesis","","","","","","","","","Civil Engineering and Geosciences","","","","",""
"uuid:d9d6277c-9862-4906-ba95-34d4bd60cb31","http://resolver.tudelft.nl/uuid:d9d6277c-9862-4906-ba95-34d4bd60cb31","Monitoring pilot projects on bored tunnelling: The Second Heinenoord Tunnel and the Botlek Rail Tunnel","Bakker, K.J.; De Boer, F.; Admiraal, J.B.M.; Van Jaarsveld, E.P.","","1999","Two pilot projects for bored tunnelling in soft soil have been undertaken in the Netherlands. The monitoring was commissioned under the authority of the Centre for Underground Construction (COB). A description of the research related to the Second Heinenoord Tunnel and the Botlek Rail Tunnel will be given. The Second Heinenoord Tunnel has completed its boring works, while the boring of the Botlek Rail Tunnel has started in march/April 1999. Experience from the first project is put into use for the development of the latter. Both monitoring schemes have three logical phases: predictions, measuring and evaluation. An overview of all instrumentation and a selection of the results of the Second Heinenoord tunnel are given.","tunnels; monitoring; geotechnics; construction","en","journal article","Elsevier","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:253b72c8-7029-4b3d-9eda-80cc4a34662d","http://resolver.tudelft.nl/uuid:253b72c8-7029-4b3d-9eda-80cc4a34662d","Structured Systems in Gas Separation - I Silicalite-1 Zeolite Membranes - II Manganese Based Sorbents for High-Temperature H2S Removal","Bakker, W.J.W.","Moulijn, J.A. (promotor)","1999","","","en","doctoral thesis","Ponsen en Looijen B.V.","","","","","","","","Applied Sciences","","","","",""
"uuid:fd8afc46-0aee-4be7-863f-7e4fdc34fa07","http://resolver.tudelft.nl/uuid:fd8afc46-0aee-4be7-863f-7e4fdc34fa07","Edge preserving orientation adaptive filtering","Bakker, P.; Van Vliet, L.J.; Verbeek, P.W.","","1999","","","en","conference paper","IEEE","","","","","","","","Applied Sciences","","","","",""
"uuid:695a7f9e-02eb-41ac-b4b6-ac8e58eae104","http://resolver.tudelft.nl/uuid:695a7f9e-02eb-41ac-b4b6-ac8e58eae104","InP-based spotsize converter for integration with switching devices","Stulemeijer, J.; Bakker, A.F.; Moerman, I.; Groen, F.H.; Smit, M.K.","","1999","","","en","journal article","IEEE","","","","","","","","","","","","",""
"uuid:e666367c-7db6-4966-90ef-13ff13a00b7d","http://resolver.tudelft.nl/uuid:e666367c-7db6-4966-90ef-13ff13a00b7d","Edge preserving orientation adaptive filtering","Bakker, P.; Van Vliet, L.J.; Verbeek, P.W.","","1999","","","en","conference paper","","","","","","","","","Applied Sciences","","","","",""
"uuid:017175d5-4932-4967-bab4-ae6c582900a6","http://resolver.tudelft.nl/uuid:017175d5-4932-4967-bab4-ae6c582900a6","Coastal Dynamics","Bakker, W.T.","Roelvink, J.A. (contributor); Steetzel, H.J. (contributor); Bliek, A. (contributor); Rakhorst, H.D. (contributor); Roelse, P. (contributor)","1998","This book deals on ""Coastal Dynamics"", which will be defined in a narrow sense as a mathematical theory, which starts from given equations of motion for the sediment, which leads with the continuity equation and given boundary conditions to a calculated (eventually schematized) coastal topography, which is generally a function of time. This is clearly analogous to aero- and hydrodynamics, thermo-dynamics, hydrology and other related fields. The subject of this book, however, covers only a specific part of the Coastal Dynamics. It is based upon the notion of old masters, that for a manager the back-side of a cigar-box should be large enough to evaluate all the information and anti-information which is poured over him. For instance: statements, based upon high-tech number-crunching can find a sad end when those do not match large-scale continuity. Think for instance of tidal computations, in which time-varying boundary conditions (shoals which emerge above water level during a part of the tide) are not reproduced accurately enough. The positive role of refined numerical techniques on solving problems in coastal dynamics should be stressed. However, one will not find much about it in this book. Emphasis is on physics, rather than on mathematics. It is meant for coastal managers, to inspire them, to enable them to put sensible questions and, if necessary, to say: ""Oh, no sir"". The theory would be sterile without a consideration about the validity of the equation of motion, so much the more, while these equations of motion are not as evident, straightforward and single- valued as for instance the Euler - equations in hydrodynamics. The Newtonian laws are not quite sufficient for the computation of the sediment motion, because the motion of grains is subject to stochastic processes as the shape of the grains, the shape of the granular bed surface, turbulence, irregular wave motion etc. In modern sophisticated computer models a physical approach going far into details is possible, this includes the consideration of water and sand apart from each other, investigation of turbulent and viscous forces on the grains, and calculation of the sediment motion.","coastal morphology; coastal processes","en","report","TU Delft, Section Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:6a5c5969-6122-4760-a7be-6533a7ae179e","http://resolver.tudelft.nl/uuid:6a5c5969-6122-4760-a7be-6533a7ae179e","Waterbouwkundige kunstwerken: Bijzondere Onderwerpen","Vrijling, J.K.; Bezuyen, K.G.; Elias, E.P.L.; Bakker, K.J.","","1998","","","nl","lecture notes","TU Delft, Department Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:4e292bd1-bd9d-4e7e-ae09-90e953f75acf","http://resolver.tudelft.nl/uuid:4e292bd1-bd9d-4e7e-ae09-90e953f75acf","Boundary-Layer Separation in Aircraft Aerodynamics: Dedicated to Professor J .L. van Ingen","Henkes, R.A.W.M.; Bakker, R.G.","","1997","","","en","book","Delft University Press","","","","","","","","Aerospace Engineering","","","","",""
"uuid:df5d5b25-0a6f-4c65-93f7-8c7f2354762e","http://resolver.tudelft.nl/uuid:df5d5b25-0a6f-4c65-93f7-8c7f2354762e","Chopper amplifier circuit with CMOS switches and amplifier FETs","Huijsing, J.H.; Bakker, A.","","1997","Abstract of NL 1001231 (C2) The input voltage is fed to the inputs of an operational amplifier via a chopping reversal switchThe CMOS operational amplifier has a current source and a current mirror. The operational amplifier output is fed to an output circuit. The possible offset voltage is suppressed by the operation of a synchronised chopper circuit between the drains of the CMOS transistors and the current mirror.","","nl","patent","European Patent Office","","","","","","","","","","","","",""
"uuid:03f08bd6-d268-4443-b671-7bd9051fa522","http://resolver.tudelft.nl/uuid:03f08bd6-d268-4443-b671-7bd9051fa522","Sodium-doped dimer rows on Si(001)","Haye, M.J.; Scholte, P.M.L.O.; Bakker, A.F.; de Leeuw, S.W.; Tuinstra, F.; Brocks, G.","","1997","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:d74e9e03-5c94-477d-a355-4788296c1bdf","http://resolver.tudelft.nl/uuid:d74e9e03-5c94-477d-a355-4788296c1bdf","Micromixing in chemical reactors, models, experiments and simulations","Bakker, R.A.","Van den Akker, H.E.A. (promotor)","1996","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:77373e30-eb6d-4974-b3e0-16320c650fe3","http://resolver.tudelft.nl/uuid:77373e30-eb6d-4974-b3e0-16320c650fe3","Het Zwin, successen en lessen: Bresgroeiexperimenten op 6 en 7 oktober 1994","Bakker, W.T.; Van de Graaff, J.; Kraak, A.W.; Smit, M.J.; Snip, D.W.; Steetzel, H.J.; Visser, P.J.","","1996","Op 6 en 7 oktober 1994 hebben twee grootschalige damdoorbraakexperimenten plaatsgevonden in Het Zwin in Zee uwsch-Vlaanderen. Vooral het eerste experiment op 6 oktober heeft veel publicitaire aandacht getrokkcn. Op het beslissende ogenblik, het begin van de proef rondom het tijdstip van hoogwater, verliep deze proef niet volgens verwachting. Het doorbraakproces kwam slecht op gang. Uiteindelijk werd een bescheiden gat bereikt; de gatbreedte bedroeg aan het eind van de proef ongeveer 13 meter. Direct na de afloop van de proef op 6 oktober werd besloten de proef op 7 oktober te herhalen. Op 7 oktober verliep de proef volledig naar wens. In 1 uur tijd werd uiteindelijk een gatbreedte van ongeveer 41 meter bereikt. In deze rapportage wordt een samenvatting van de achtergronden, de voorbereiding en het verloop van de beide proeven gegeven. Aan de successen die zijn behaald en de lessen die z ijn geleerd, wordt aandacht besteed. De proeven vormen een onderdeel van het onderzoek naar dijkdoorbraakprocessen dat in opdracht van de Dienst Weg- en Waterbouwkunde van Rijkswaterstaat voor de Technische Adviescommissie voor de Waterkeringen wordt uitgevoerd. Omdat het in deze gevallen om onverdedigde zanddammen gaat, wordt in deze rapportage steeds de term 'damdoorbraak' in plaats van 'dijkdoorbraak' gebruikt.","breach; dune; dambreak","nl","report","TAW","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:61ee6025-bc7e-4c48-a7d8-d1d1b3f5e930","http://resolver.tudelft.nl/uuid:61ee6025-bc7e-4c48-a7d8-d1d1b3f5e930","Micropower CMOS temperature sensor with digital output","Bakker, A.; Huijsing, J.H.","","1996","","","en","journal article","IEEE","","","","","","","","","","","","",""
"uuid:7bda6b3d-b298-46a4-8f34-812fc3d249c3","http://resolver.tudelft.nl/uuid:7bda6b3d-b298-46a4-8f34-812fc3d249c3","Neural network model to control an experimental chaotic pendulum","Bakker, R.; Schouten, J.C.; Takens, F.; van den Bleek, C.M.","","1996","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:35b9dbef-3718-40fc-b64a-178b1cd0fed8","http://resolver.tudelft.nl/uuid:35b9dbef-3718-40fc-b64a-178b1cd0fed8","Environmental Information for Industrial Designers","Bakker, C.A.","Vergragt, Ph.J. (promotor); Brezet, J.C. (promotor)","1995","","eco-design; industrial design; information; design methodology","en","doctoral thesis","","","","","","","","","Industrial Design Engineering","","","","",""
"uuid:40d9ad86-21e4-46f9-8daa-e610b9bd13df","http://resolver.tudelft.nl/uuid:40d9ad86-21e4-46f9-8daa-e610b9bd13df","Mechanical Behaviour of Materials","Bakker, A.","","1995","","","en","book","Delft University Press","","","","","","","","","","","","",""
"uuid:cc36dd9e-27c6-4c60-9612-bde5c6a40a17","http://resolver.tudelft.nl/uuid:cc36dd9e-27c6-4c60-9612-bde5c6a40a17","Mixed oxidant corrosion in nonequilibrium syngas at 540^o C","Bakker, W.T.","De Wit, J.H.W. (promotor)","1995","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:bf792ef5-b403-402b-a1be-203de879cf7a","http://resolver.tudelft.nl/uuid:bf792ef5-b403-402b-a1be-203de879cf7a","7th International Conference on Mechanical Behaviour of Materials: Book of abstracts","Bakker, A.","","1995","","deformation; damage; fracture","en","book","Delft University Press","","","","","","","","Applied Sciences","Materials Laboratory","","","",""
"uuid:c2e17927-ec44-49e8-b228-648ce1c808ba","http://resolver.tudelft.nl/uuid:c2e17927-ec44-49e8-b228-648ce1c808ba","Integratie van een brandstofcel (MCFC) in een kolenvergassings-energiecentrale (Buggenum) met ontzwaveling (HT) en CO2-terugwinning","Bakker, W.; Geveke, K.; Van Rossem, B.","","1995","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:3deb2376-a781-4f24-8d5e-e96f3eb24a06","http://resolver.tudelft.nl/uuid:3deb2376-a781-4f24-8d5e-e96f3eb24a06","De dehydrogenering van propaan in een packed bed membrane reactor","Bakker, S.E.H.; Vleeshouwers, A.M.W.; Verkoeijen, D.","","1994","Document(en) uit de collectie Chemische Procestechnologie","dehydrogenering; packed bed membrane reactor; propaan; propeen","en","report","Delft University","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:d4db863d-9eaf-468f-8c2e-24cb412e6835","http://resolver.tudelft.nl/uuid:d4db863d-9eaf-468f-8c2e-24cb412e6835","Planar semiconductor coupled superconducting devices","Bakker, S.J.M.","Radelaar, S. (promotor); Klapwijk, T.M. (promotor)","1994","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:528e6aa3-952a-4590-b73e-44d08ac05d19","http://resolver.tudelft.nl/uuid:528e6aa3-952a-4590-b73e-44d08ac05d19","Modelling of separation using Euler methods","Houtman, E.M.; Bakker, P.G.; de Vries, E.; van den Berg, J.C.","","1994","","Inviscid separation; Euler method; Kutta condition; vortex flow","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:906b2ed8-1ba4-4402-87fc-60ced98f86fe","http://resolver.tudelft.nl/uuid:906b2ed8-1ba4-4402-87fc-60ced98f86fe","A Semantic Approach to Enforce Correctness of Data Distribution Schemes","Bakker, J.A.","","1994","","","en","journal article","Oxford University Press","","","","","","","","","","","","",""
"uuid:8164d50e-f6db-42ec-8076-4cd380a0a722","http://resolver.tudelft.nl/uuid:8164d50e-f6db-42ec-8076-4cd380a0a722","Flow visualization study of high supersonic flow past a blunt cylinder-cone flare body","Bakker, P.G.; Bannink, W.J.","","1994","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:fc80d0f2-7af5-4b61-a08b-e041fe84ca10","http://resolver.tudelft.nl/uuid:fc80d0f2-7af5-4b61-a08b-e041fe84ca10","Observation of carrier-concentration-dependent reflectionless tunneling in a superconductor-two-dimensional-electron-gas-superconductor structure","Bakker, S.J.M.; van der Drift, E.; Klapwijk, T.M.; Jaeger, H.M.; Radelaar, S.","","1994","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:25b9b392-606c-4fa1-a480-273fd6b3122a","http://resolver.tudelft.nl/uuid:25b9b392-606c-4fa1-a480-273fd6b3122a","Effect of tidal resonance on the morphology of Wadden and Estuaries","Bakker, W.T.","","1993","Contains basic paper plus background supplements. Areas like the Western Wadden area have a length of approximately 1/4 of a tidal wave length. Therefore tidal motion is sensible for resonance. It is investigated, under which circumstances morphological instabilities may occur. Instabilities are defined in this way, that small depth increments intensifies the vertical tidal amplitude in the basin, which in turn triggers increased erosion of the basin. For prismatical channels, occurrence of instabilities depend on the length of the basin and the bottom roughness. Dimensionless criteria are given. Effects of shoals are discussed.","tide; resonance; estuaries; shallow seas","en","conference paper","Netherlands Centre for Coastal Research (NCK)","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:3d64eac4-5512-40a0-9ebc-42911a30629a","http://resolver.tudelft.nl/uuid:3d64eac4-5512-40a0-9ebc-42911a30629a","Hypersonic test facility Delft HTF-Delft","Bannink, W.J.; Bakker, P.G.","","1993","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:3b8fc364-31e4-4aef-96d2-c809569252be","http://resolver.tudelft.nl/uuid:3b8fc364-31e4-4aef-96d2-c809569252be","Hypersonic airbreathing reusable advanced launcher: A feasibility study","Bakker, J.; Vossepoel, F.C.; Kraa, A.R.; Broomhead, M.J.; van Vliet, L.D.; van Luipen, J.J.W.; Cremers, G.; Sprenger, M.L.M.; Frenken, G.W.R.; Punt, P.C.","Zandbergen, B.T.C. (contributor)","1993","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:9c889fc1-6d1f-4341-8e2b-554a17cae717","http://resolver.tudelft.nl/uuid:9c889fc1-6d1f-4341-8e2b-554a17cae717","Permeation measurements on in situ grown ceramic MFI type films","Geus, E.R.; Bakker, W.J.W.; Verheijen, P.J.T.; Den Exter, M.J.; Moulijn, J.A.; Van Bekkum, H.","","1993","Continuous MFI type films were grown on macroporous ceramic clay-type supports. Permeation experiments were performed using a Wicke-Kallenbach experimental set-up. Applying helium as an inert carrier gas, the permeation behaviour of strongly (n-butane, isobutane), and weakly adsorbing species (neon, argon, methane) was studied at room temperature for both ’pure’ gases, and binary mixtures. Significant differences in permeation behaviour were found between strongly and weakly adsorbing gases, although steady state permeation rates varied less than one order of magnitude. The lower diffusivity of heavier alkanes is compensated.by the higher sorbate concentration within the zeolite micropores. Accordingly, only low selectivities were found for binary mixtures, where the permeation rate is governed by the slowest moving species. For sorption near or within the Henry region, substantially higher selectivities were obtained. The presence of a macroporous layer on one side of the membrane will lead to reduced permeation rates, especially for strongly adsorbing molecules.","","en","conference paper","Butterworth-Heinemann","","","","","","","","Applied Sciences","Applied Chemistry","","","",""
"uuid:a341ca4a-8198-4120-b78b-64f603c99622","http://resolver.tudelft.nl/uuid:a341ca4a-8198-4120-b78b-64f603c99622","Superconductivity and localization in thin polycrystalline tungsten-germanium films","Bakker, S.J.M.; Jaeger, H.M.; Klapwijk, T.M.; van der Drift, T.; Radelaar, S.","","1993","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:72f900b2-c736-4113-92f9-29c5335548b9","http://resolver.tudelft.nl/uuid:72f900b2-c736-4113-92f9-29c5335548b9","Essays on aerodynamics: A collection of scientific papers and some personal impressions dedicated to Professor J.A. Steketee","Bakker, P.G.; Coene, R.; Van Ingen, J.L.","","1992","","aerodynamica","en","book","Delft University Press","","","","","","","","Delft University of Technology","","","","",""
"uuid:c9246d0d-82b1-4112-aa96-a9194ff948b8","http://resolver.tudelft.nl/uuid:c9246d0d-82b1-4112-aa96-a9194ff948b8","Hydrodynamics of Stirred Gas-Liquid Dispersions","Bakker, A.","van den Akker, H.E.A. (promotor)","1992","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:06ed2b85-664e-4c5d-b3bd-ced56a978d50","http://resolver.tudelft.nl/uuid:06ed2b85-664e-4c5d-b3bd-ced56a978d50","Spieghel en Daet; Enkele gedachten over de ontwikkeling van de hoge-snelheids aerodynamica","Bakker, P.G.","","1991","","Intreerede","nl","public lecture","","","","","","","","","","","","","",""
"uuid:c3650c37-6dd2-4564-abe1-dc8ebfbacc40","http://resolver.tudelft.nl/uuid:c3650c37-6dd2-4564-abe1-dc8ebfbacc40","Determination of the location and order of the drying transition with a molecular-dynamics simulation","Nijmeijer, M.J.P.; Bruin, C.; Bakker, A.F.; van Leeuwen, J.M.J.","","1991","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:aa0a5aba-56cf-4fa7-a9b1-b5ea59c89bb3","http://resolver.tudelft.nl/uuid:aa0a5aba-56cf-4fa7-a9b1-b5ea59c89bb3","Terugwinning van solvent voor de productie van Twaron: Verwijdering van water en zoutzuur uit een oplossing van NMP, water calciumchloride en zoutzuur","Bakker, W.J.W.; Boot, G.H.; Van den Eijkel, G.; Gerritse, A.J.; Heerink, M.; Korstanje, M.T.; De Kort, A.P.R.; Kuperus, M.; Landesz, S.C.; Nijhof, E.; Nijssen, S.J.; Ornstein, M.J.M.; Pluilaartm, A.P.H.; Putra, T.P.A; Siemers, W.V.; Sozef, A.J.","","1990","","","nl","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:a267df7e-63ff-403a-89ab-d412c92b2ece","http://resolver.tudelft.nl/uuid:a267df7e-63ff-403a-89ab-d412c92b2ece","Ammoniakproductie volgens ICI patent EP 0 212 889","Bakker, K.; Heyne, M.A.M.","","1990","Document(en) uit de collectie Chemische Procestechnologie","","en","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemtech","","","",""
"uuid:18685a5e-1f47-4708-85bd-e1990d052410","http://resolver.tudelft.nl/uuid:18685a5e-1f47-4708-85bd-e1990d052410","Wetting and drying of an inert wall by a fluid in a molecular-dynamics simulation","Nijmeijer, M.J.P.; Bruin, C.; Bakker, A.F.; Van Leeuwen, J.M.J.","","1990","","","en","journal article","American Physical Society","","","","","","","","","","","","",""
"uuid:35342f3e-5fb4-4de2-8422-610e840f08ee","http://resolver.tudelft.nl/uuid:35342f3e-5fb4-4de2-8422-610e840f08ee","Radio positioning at sea: Geodetic survey computations, least squares adjustment","Bakker, G.; De Munck, J.C.; Strang van Hees, G.L.","","1989","Student edition","coordinate computation","en","book","Delft University Press","","","","","","","","Civil Engineering and Geosciences","","","","",""
"uuid:a10d5639-817d-4c96-bb6a-f88fcd2f850a","http://resolver.tudelft.nl/uuid:a10d5639-817d-4c96-bb6a-f88fcd2f850a","DFMS: Architecture and implementation of a distributed control system for FMS","Bakker, J.J.A.","Reijers, L.N. (promotor)","1989","","flexible manufacturing systems; mechanical engineering design: computer applications","en","doctoral thesis","","","","","","","","","","","","","",""
"uuid:59e7f63d-9499-49e9-8165-6c311944aa34","http://resolver.tudelft.nl/uuid:59e7f63d-9499-49e9-8165-6c311944aa34","Three-dimensional viscous flow structures from bifurcation of a degenerate singularity with three zero eigenvalues","Kooij, R.E.; Bakker, P.G.","","1989","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:879080e6-496e-426c-b30a-dd4631713dc1","http://resolver.tudelft.nl/uuid:879080e6-496e-426c-b30a-dd4631713dc1","Bifurcations in viscous flow fields: On the genesis and development of topologically complicated separated flow structures","Bakker, P.G.","","1989","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:f3fb7eeb-2c9e-4b0b-ba85-d945ca7fe786","http://resolver.tudelft.nl/uuid:f3fb7eeb-2c9e-4b0b-ba85-d945ca7fe786","Preparation of D-xylulose from D-xylose: Enzyme and Microbial Technology","Pronk, J.T.; Bakker, A.W.; Van Dam, H.E.; Straathof, A.J.J.; Scheffers, W.A.; Van Dijken, J.P.","","1988","","D-xylulose; xylose isomerase; Acinetobacter calcoaceticus; immobilization","en","journal article","Butterworth","","","","","","","","Applied Sciences","","","","",""
"uuid:103bb8a1-3778-433f-8847-7d20905c5c2a","http://resolver.tudelft.nl/uuid:103bb8a1-3778-433f-8847-7d20905c5c2a","Bifurcations in flow patterns: Some applications of the qualitative theory of differential equations in fluid dynamics","Bakker, P.G.","Reyn, J.W. (promotor)","1988","","","en","doctoral thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","","","","",""
"uuid:03e88483-ac83-4c45-a222-b2d348821655","http://resolver.tudelft.nl/uuid:03e88483-ac83-4c45-a222-b2d348821655","On the topology of three-dimensional viscous flow structures near a plane wall: A classification of hyperbolic and non-hyperbolic singularities on the wall","de Winkel, M.E.M.; Bakker, P.G.","","1988","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:d2de4bc6-30c0-4e2b-9b5d-706aa48e2206","http://resolver.tudelft.nl/uuid:d2de4bc6-30c0-4e2b-9b5d-706aa48e2206","Coastal changes, caused by a shallow water sanddam in front of the Delfland coast","Bakker, W.T.; Delver, G.","","1986","Along tht coastline at Ter Heijde, near Delft, a dam parallel to the coast in shallow water will be constructed havlng a horizontal crest at the level NAP -3 m on the landward side, merging into the existing coastal profile and having on the seaward side a slope 1:20. The dam will have a length of 1.5 km (fig. 1). This work will be carried out as a part of a large experiment with sanddams including a larger dam in deep water, reaching from NAP -10 m to NAP -3 m. The following questions are to be answered in order to predict and judge the effects that this work will have on the erosion and accretion process of the shoreline: How much is treatment of sand with which the beach above the NAP -3 m depth line will accrete. What will be the location in time of the amount of accretion of sand along the coastline.","nearshore nourishment; beach nourishment; zandmotor","en","report","TU Delft, Department Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:a69a7b77-377e-42f0-861d-5e94790323a7","http://resolver.tudelft.nl/uuid:a69a7b77-377e-42f0-861d-5e94790323a7","Berekening drukverdelingen op supersone delta-vleugels m.b.v. stuwpunts-oplossingen","Vreenegoor, A.J.N.; Bakker, P.G.","","1986","","","nl","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:9027ab9a-18d2-4655-a95a-d9cbcb04a239","http://resolver.tudelft.nl/uuid:9027ab9a-18d2-4655-a95a-d9cbcb04a239","Berekening van de scheidingskosten in een 2,6-xylenol-synthese fabriek","Bakker, G.; Brankman, P.; Van der Donk, H.; Hadimoeljono, A.; De Jong, H.J.; Meijer, K.; Rots, A.","","1985","Document uit de collectie Chemische Procestechnologie","","nl","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:c7b4cbd7-fde7-4167-8dc4-fdd03d579840","http://resolver.tudelft.nl/uuid:c7b4cbd7-fde7-4167-8dc4-fdd03d579840","Ontwerp van de scheidingssectie van een 2,6-xylenol synthese fabriek","De Jonge, W.J.; De Jong, H.J.; Haastrecht, F.M.; Bakker, G.; Bruinsma, C.J.","","1985","","","nl","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:bd1aaad7-3574-4e4d-92e1-4d7537090aae","http://resolver.tudelft.nl/uuid:bd1aaad7-3574-4e4d-92e1-4d7537090aae","The three-dimensional J-integral: An investigation into its use for post-yield fracture safety assessment","Bakker, A.","Latzko, D.G.H. (promotor)","1984","","","en","doctoral thesis","","","","","","","","","Mechanical, Maritime and Materials Engineering","Mechanical, Maritime and Materials Engineering","","","",""
"uuid:b1559b39-6763-4758-9421-b1862eeea675","http://resolver.tudelft.nl/uuid:b1559b39-6763-4758-9421-b1862eeea675","Structural stability and bifurcation in conical flow fields","Bakker, P.G.","","1984","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:0d17ea93-99d6-4e76-b82d-66f789e816f9","http://resolver.tudelft.nl/uuid:0d17ea93-99d6-4e76-b82d-66f789e816f9","Design and implementation of the Delft molecular-dynamics processor","Bakker, A.F.","Veltman, B.P.Th. (promotor)","1983","","","en","doctoral thesis","(c) 1983 Bakker, A.F.","","","","","","","","Applied Sciences","Applied Sciences","","","",""
"uuid:c5468659-c25a-47e1-b282-5e88bc5b5c9d","http://resolver.tudelft.nl/uuid:c5468659-c25a-47e1-b282-5e88bc5b5c9d","Transonic Mach number determination in a blow-down wind-tunnel with solid walls and a downstream throat","Bannink, W.J.; Bakker, P.G.","","1983","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:a7b00333-26bd-40d4-88c7-7289c376847c","http://resolver.tudelft.nl/uuid:a7b00333-26bd-40d4-88c7-7289c376847c","On Bifurcation phenomenae in conical flow patterns","Bakker, P.G.","","1983","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:8775dc02-b966-4ac6-a933-0c1a9a75aed7","http://resolver.tudelft.nl/uuid:8775dc02-b966-4ac6-a933-0c1a9a75aed7","Conical stagnation points in the flow around an external corner","Bakker, P.G.; Reyn, J.W.","","1983","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:f1d36bc3-7b76-4d31-b7b3-2742fc60183b","http://resolver.tudelft.nl/uuid:f1d36bc3-7b76-4d31-b7b3-2742fc60183b","Probabilistic design of sea defences","Bakker, W.T.; Vrijling, J.K.","","1980","","sea defence; safety; probabilistic design","en","report","TU Delft, Section Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:988c552b-a0e1-44cf-9098-724c865b750b","http://resolver.tudelft.nl/uuid:988c552b-a0e1-44cf-9098-724c865b750b","On the structure of the potential flow field near conical stagnation points in supersonic flow","Bakker, P.G.; Bannink, W.J.; Reyn, J.W.","","1980","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:0d539411-552f-41b0-86ae-31a69d5ff3ed","http://resolver.tudelft.nl/uuid:0d539411-552f-41b0-86ae-31a69d5ff3ed","Bepaling van het getal van Mach van de transsone stroming in de TST 27 windtunnel met dichte wanden","Bannink, W.J.; Bakker, P.G.","","1979","","","nl","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:7d862ed6-8f78-4c0a-bfa3-2526a9b55051","http://resolver.tudelft.nl/uuid:7d862ed6-8f78-4c0a-bfa3-2526a9b55051","Degradation of aromatic compounds by micro-organisms in dissimilatory nitrate reduction","Bakker, G.","Wikén, T.O. (promotor)","1977","","","en","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:a555b1e2-22f0-477a-9d13-dd6263a879ad","http://resolver.tudelft.nl/uuid:a555b1e2-22f0-477a-9d13-dd6263a879ad","Conical streamlines and pressure distribution in the vicinity of conical stagnation points in isentropic flow","Bakker, P.G.","","1977","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:57bdc679-bb17-459d-9df3-f24447053691","http://resolver.tudelft.nl/uuid:57bdc679-bb17-459d-9df3-f24447053691","Properties of subscribers' lines and their influence on telephone transmission performance","Bakker, C.","Bordewijk, J.L. (promotor)","1976","","","en","doctoral thesis","Staatsbedrijf der Posterijen, Telegrafie en Telefonie","","","","","","","","Electrical Engineering, Mathematics and Computer Science","","","","",""
"uuid:8e1de08d-9f82-4cb1-8162-b675e8cd4afe","http://resolver.tudelft.nl/uuid:8e1de08d-9f82-4cb1-8162-b675e8cd4afe","Conical stagnation points in the supersonic flow around slender circular cones at incidence","Bakker, P.G.; Bannink, W.J.","","1974","","","en","report","Delft University of Technology","","","","","","","","Aerospace Engineering","","","","",""
"uuid:316fb62d-fca4-4f17-8764-6320733fb3c0","http://resolver.tudelft.nl/uuid:316fb62d-fca4-4f17-8764-6320733fb3c0","LEED-onderzoek naar reacties van het (111)-oppervlak van tantaal","Bakker, L.","Okkerse, B. (promotor)","1972","","","nl","doctoral thesis","","","","","","","","","Mechanical, Maritime and Materials Engineering","","","","",""
"uuid:eccf0124-8e1a-4c08-8815-cf088cd44851","http://resolver.tudelft.nl/uuid:eccf0124-8e1a-4c08-8815-cf088cd44851","Computerprogramma's welke bij de Technische Hogeschool zijn ontwikkeld betreffende: Kusten, kustverdediging en aanverwante onderwerpen","Franzen, F.; Bakker, W.T.","","1972","Korte beschrijvingen van kustwaterbouwkundige software met verwijzingen naar achtergronddocumenten","software; kustwaterbouw","nl","report","TU Delft, Section Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:be20dc24-51c9-47ab-b3b0-90def7a7910a","http://resolver.tudelft.nl/uuid:be20dc24-51c9-47ab-b3b0-90def7a7910a","De dynamica van kusten","Bakker, W.T.","","1971","Overzicht van kustdynamica, éénlijntheorie, Pelnard-Considère, tweelijn theorie, kustconstanten, effect strandhoofden en havendammen, invloed radiation stress, muistromen","kustmorfologie; kustdynamica","nl","report","Stichting PAO","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:b98f4eb5-e2a4-46c1-96cd-201a060ab4b9","http://resolver.tudelft.nl/uuid:b98f4eb5-e2a4-46c1-96cd-201a060ab4b9","An experimental integrated system for application of a computer in shipbuilding industry","Bakker, A.R.","Van Spiegel, E. (promotor)","1970","","","en","doctoral thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","","","","",""
"uuid:10c37194-1e9a-49e5-8b67-45ddfd6840b3","http://resolver.tudelft.nl/uuid:10c37194-1e9a-49e5-8b67-45ddfd6840b3","Microspheres with Ultrahigh Holmium Content for Radioablation of Malignancies","Bult, W.; Seevinck, P.R.; Krijger, G.C.; Visser, T.; Kroon-Batenburg, L.M.J.; Bakker, C.J.G.; Hennink, W.E.; Van het Schip, A.D.; Nijsen, J.F.W.","","","Purpose The aim of this study was to develop microspheres with an ultra high holmium content which can be neutron activated for radioablation of malignancies. These microspheres are proposed to be delivered selectively through either intratumoral injections into solid tumors or administered via an intravascularly placed catheter. Methods Microspheres were prepared by solvent evaporation, using holmium acetylacetonate (HoAcAc) crystals as the sole ingredient. Microspheres were characterized using light and scanning electron microscopy, coulter counter, titrimetry, infrared and Raman spectroscopy, differential scanning calorimetry, X-ray powder diffraction, magnetic resonance imaging (MRI), and X-ray computed tomography (CT). Results Microspheres, thus prepared displayed a smooth surface. The holmium content of the HoAcAc microspheres (44% (w/w)) was higher than the holmium content of the starting material, HoAcAc crystals (33% (w/w)). This was attributed to the loss of acetylacetonate from the HoAcAc complex, during rearrangement of acetylacetonate around the holmium ion. The increase of the holmium content allows for the detection of (sub)microgram amounts of microspheres using MRI and CT. Conclusions HoAcAc microspheres with an ultra-high holmium content were prepared. These microspheres are suitable for radioablation of tumors by intratumoral injections or treatment of liver tumors through transcatheter administration.","holmiumacetylacetonate; intratumoral; microspheres; multimodality; radioablation","en","journal article","Springer","","","","","","","","Applied Sciences","Radiation, Radionuclides and Reactors","","","",""
"uuid:4390fe4d-8866-4e04-ac7c-2b1663229788","http://resolver.tudelft.nl/uuid:4390fe4d-8866-4e04-ac7c-2b1663229788","Grensvlakstroming en stofoverdracht tussen beweeglijke fasen","Bakker, C.A.P.","Kramers, H. (promotor); Beek, W.J. (promotor)","1965","","","nl","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:4f3d4c16-0c4f-4d7b-b271-482076410779","http://resolver.tudelft.nl/uuid:4f3d4c16-0c4f-4d7b-b271-482076410779","De levertijd in machinefabrieken: Een oriënterend onderzoek","Bakker, W.","Van Hasselt, R. (promotor)","1965","","","nl","doctoral thesis","Uitgeverij Waltman, Delft","","","","","","","","Mechanical, Maritime and Materials Engineering","","","","",""
"uuid:c28e9762-23c3-41d4-bd52-c0188ae2fb3b","http://resolver.tudelft.nl/uuid:c28e9762-23c3-41d4-bd52-c0188ae2fb3b","Zwavelkoolstof CS2","Bakker, J.G.","","1964","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:4fba0274-2429-4818-89fb-ecdcafae1e4a","http://resolver.tudelft.nl/uuid:4fba0274-2429-4818-89fb-ecdcafae1e4a","Verslag behorende bij het processchema: Bereiding van ethyleenglycol","Bakker, P.G.","","1964","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:ff955f7d-83a1-489f-a182-007a36900584","http://resolver.tudelft.nl/uuid:ff955f7d-83a1-489f-a182-007a36900584","Verslag over het processchema voor de bereiding van dichloorethaan uit etheen en chloor","Bakker, L.","","1963","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:eec123de-7768-4505-976b-835aa5632688","http://resolver.tudelft.nl/uuid:eec123de-7768-4505-976b-835aa5632688","Fabrieksschema voor de bereiding van styreen","Bakker, G.","","1962","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University of Technology","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:108a6697-0253-40e0-92b5-97d9ed097330","http://resolver.tudelft.nl/uuid:108a6697-0253-40e0-92b5-97d9ed097330","Raffinage van ruwe benzol uit cokesovengas","Bakker, C.","","1959","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University","","","","","","","","Applied Sciences","DelftChemTech","","","",""
"uuid:2d104378-84b6-4cdc-9827-1e626b4c9741","http://resolver.tudelft.nl/uuid:2d104378-84b6-4cdc-9827-1e626b4c9741","Porositeitsmetingen in een gefluidiseerd bed","Bakker, P.J.","Heertjes, P.M. (promotor)","1958","","","nl","doctoral thesis","","","","","","","","","Applied Sciences","","","","",""
"uuid:8b49efd9-1629-4e0b-9bdd-2436bb0ebbd6","http://resolver.tudelft.nl/uuid:8b49efd9-1629-4e0b-9bdd-2436bb0ebbd6","Ontwerp voor een katalytische fluid-bed kraakinstallatie","Okkerse, B.; Bakker, P.J.","","1952","Document(en) uit de collectie Chemische Procestechnologie","","nl","report","Delft University","","","","","","","","Applied Sciences","DelftChemTech","","","",""