"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:b1fca71b-50fb-4f17-bcad-66ac9ccc3dfb","http://resolver.tudelft.nl/uuid:b1fca71b-50fb-4f17-bcad-66ac9ccc3dfb","Sound understanding and urban topology: An alternative approach to sound perception in existent fabric","Huang, T.","Oosterhuis, K. (mentor); Biloria, N. (mentor); Vollers, K. (mentor)","2008","","sound","en","master thesis","TU Delft, Architecture, Architecture","","","","","","","","Architecture","","","","",""
"uuid:47c1536e-cffb-4983-8c13-109152253dbb","http://resolver.tudelft.nl/uuid:47c1536e-cffb-4983-8c13-109152253dbb","Development of a design tool for the integration of public art in a built environment","Huang, C.Y.","Birkhoff, R.A. (mentor); Buijs, J.A. (mentor)","2009","Public art is the artwork in any media that has been planned and executed with the specific intention of being sited or staged in the public domain, which is accessible to all. Public art can be preformed in different manners: permanent or temporary, art installation or art promotion events or programs. For large public building projects almost all over the world it is required to allocate a certain percentage of the total construction budget (usually 1%) for the installation of public art if the total construction budget exceeds a certain amount of money. It is meant for encouraging the integration of art in the environment and to enable the art to be a part of citizen’s daily life. In the early days, the most common approach was to place a piece of still sculpture on a square, entrance or the lobby; however, nowadays more and more clients and architects are interested in how to merge art into a building in a more innovative and meaningful way. Architects are often requested by the clients to provide a proposal or a feasibility study for the public art issue. Accordingly, the goal of this study is to develop a design tool for the architects to facilitate the design process of integrating public art and the building project. To merge art and the environment, one of the approaches, which is also the main concept of this study, is to promote the artwork ,which is more contextual-based, able to provide certain function and interact with the users. Based on this concept, the key elements of the public art and the built environment were analyzed, the approaches for integration of art and the built environment were categorized, and the criteria of functional public art were specified as well. In the end, the design tool, a booklet, was developed and tested by a Taiwanese project, Wei-Wu-Ying Center for the Performing Arts in Kaohsiung.","design tool; public art; built environment","en","master thesis","","","","","","","Campus only","","Industrial Design Engineering","Product Innovation Management","","","",""
"uuid:98b8ad34-2c5e-4033-bac5-41b37e46f22e","http://resolver.tudelft.nl/uuid:98b8ad34-2c5e-4033-bac5-41b37e46f22e","""Eroding on the edges"": Integration Stategy for Western Fringe of Xi'An City as a supportive urban tissue in Mega City Plan 2020+","Huang, Y.","Sepúlveda, D. (mentor); Harteveld, M. (mentor)","2011","The project focuses on how to combine the current corridor development and the cultural & historic assets by means of the public space network, in order to counteract the fragmentation at the local level and meanwhile benefit the local inhabitants of western fringe of Xi’an City, supplementing the governmental city model.","public space network; local value; landscape","en","master thesis","","","","","","","","","Architecture","Urbanism","","Studio: complex cities","",""
"uuid:42e70d61-0c0b-477c-a6ed-45d8d7892b19","http://resolver.tudelft.nl/uuid:42e70d61-0c0b-477c-a6ed-45d8d7892b19","Multi-Carrier Wakeup Radio Receiver","Huang, Z.","Leus, G. (mentor)","2011","In the development of wireless sensor networks, power consumption is one of the bottlenecks for wide applications. In order to improve the energy efficiency of wireless sensor networks, a wakeup radio scheme is presented. The main transceiver that is responsible for data communication is in the sleep mode most of the time. An additional device called the wakeup radio receiver is a simplified receiver with much lower power consumption and data rate than the main transceiver. It is always on to monitor the channels continuously. It detects the wakeup packet, and sends the main transceiver a wakeup trigger upon successful detection of a wakeup packet. However, the detection of a wakeup packet is a challenging task. Since the wakeup radio receiver operates in the 2.4 GHz industrial, scientific, and medical band, a wakeup packet can be greatly interfered in such a noisy channel, which may lead to detection performance degradation. Therefore, a multi-carrier wakeup radio receiver is proposed as a solution to interference mitigation by making use of frequency diversity. But in practical implementations, the impairments from the multi-carrier wakeup receiver itself cannot be neglected. The receiver detection performance may degrade due to the non-idealities at the receiver. In this thesis, the detection performance of the multi-carrier wakeup radio receiver in the presence of channel noise, fading, co-channel interference, as well as non-idealities is explored.","wireless sensor network; wakeup radio receiver; detection performance; non-idealities","en","master thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","Telecommunications","","Telecommunications","",""
"uuid:5cc01f8f-52be-4811-b8ae-fec6e9f74f6b","http://resolver.tudelft.nl/uuid:5cc01f8f-52be-4811-b8ae-fec6e9f74f6b","Throughput-constrained Voltage and Frequency Scaling for Real-time heterogeneous multiprocessors","Huang, P.","Moreira, O. (mentor); Goossens, K. (mentor); Molnos, A. (mentor)","2011","Voltage and Frequency Scaling (VFS) has been shown to reduce energy consumption effectively on system level. Most existing work in this field focused on deadline-constrained applications with finite schedule lengths. However, in typical real-time streaming applications, data processing is constantly activated by infinitely long data streams and operations on successive data instances are overlapped to achieve a tight throughput. This necessitates new VFS policies to perform energy efficient processing. In this thesis, we solve throughput-constrained VFS problems for real-time streaming applications with discrete frequency levels on a heterogeneous multi-processor platform. We propose discrete scaling algorithms for a multi-clock domains platform with local voltage switches per processor and for a single-clock domain platform with a global voltage switch for all processors. We prove NP-hardness for the local VFS problem and maximal open for the global VFS problem. A mixed integer linear program (MILP) is formulated for our local voltage scaling algorithm, while for its global counterpart, a three-stage heuristic incorporating MILP is proposed. Furthermore, two extensions of the proposed voltage scaling policies are presented to handle transition overheads and to include application level Time-Division Multiplexing (TDM) schedulers. Experiments show that for our modem application examples, the discrete local VFS algorithm achieves energy savings close to its continuous counterpart, and local voltage switching is much more beneficial in terms of energy saving than global voltage switching. For example, for our Wireless LAN (WLAN) application example, the continuous local VFS algorithm reduces energy by 29.62%, while the discrete local and global VFS algorithms reduce energy by 28.03% and 16.49%, respectively.","voltage and frequency scaling; real time; streaming applications; mathematical programming","en","master thesis","","","","","","","","2013-01-01","Electrical Engineering, Mathematics and Computer Science","Microelectronics & Computer Engineering","","Computer Engineering","",""
"uuid:e30d8cd1-4925-4f27-a0f3-785e2df75674","http://resolver.tudelft.nl/uuid:e30d8cd1-4925-4f27-a0f3-785e2df75674","Dynamic PTDF Implementation in the Market Model","Huang, D.","Gibescu, M. (mentor); Pelgrum, E. (mentor); Ciupuliga, A. (mentor)","2011","This master thesis aims at developing the methodology to form dynamic PTDF families, for the implementation into the market model. The main procedures to create a dynamic PTDF family are developed and presented with a study case (See Chapter 4). By fitting data from the market model into the data mining tools, typical scenarios of the time intervals are selected. Furthermore, by dividing subareas according to nodal PTDF values, the resulted estimation power flow is getting closer to the real flow, as depicted in section 4.4 for the study case. In addition, the outliers of the initial input data are located and more typical scenarios are selected from this outlier data group. The effectiveness of the dynamic PTDF family is demonstrated by comparing the estimated power flow using the dynamic PTDF matrices, a fixed PTDF matrix and the real power flow calculated in PSSE, given the same economic dispatch run by Powrsym4 simulation without PTDF logic. The results reveal that with the dynamic PTDF family adopted, the power flow estimation error is significantly reduced in comparison with using a fixed PTDF matrix. In the study case, the peak value of the estimation error is reduced by 67%. The average error of the estimated power flow reduced from 16.9% with one fixed PTDF matrix to 3.7% when we adopt the PTDF family. In the last part of the thesis, the implementation of dynamic PTDF matrix in the market model is simulated with a Matlab economic dispatch model for one hour. The influence of incorporating dynamic PTDF matrix into the UC-ED decision is investigated. The UC-ED results and PSSE power flows are compared for cases without PTDF logic, with simple PTDF logic (only one fixed PTDF matrix) and with dynamic PTDF matrix. At last, an implementation scheme of the dynamic PTDF family for the UC-ED decision making is proposed.","zonal market model; dynamic PTDF; data mining; k-medoids; silhouette","en","master thesis","","","","","","","","2012-02-10","Electrical Engineering, Mathematics and Computer Science","Electrical Sustainable Energy","","Electrical Power Systems","",""
"uuid:6cfbb3e6-8a2d-44fe-8c6c-7beb1cbd0f2a","http://resolver.tudelft.nl/uuid:6cfbb3e6-8a2d-44fe-8c6c-7beb1cbd0f2a","Integrating the online and physical apparel shopping experience","Huang, P.R.Y.S.","Christiaans, H.H.C.M. (mentor); Pasman, G.J. (mentor); Schiet, R. (mentor)","2012","The assignment was to study both the physical and the online shopping channel in order to design a concept integrating and thereby enhancing the physical and online shopping experience of Denim+ as a brand. The integrated solution must be intuitive in navigation and easy-to-use for the future customers of Denim+. Denim+ is a denim lifestyle brand store, set-up in 2010 and is located in Bussum. Denim+ sells jeans, basics and accessories. Next to the physical shop, the web shop was launched in November 2010, selling the same products. The report describes two major phases: the analysis phase and the synthesis phase. The analysis phase explores Denim+ internally and externally. The synthesis phase describes the process of idea generation, concept development and the final concept named PLUS. The internal analysis describes Denim+’ online and physical store marketing mix and branding. Both are evaluated and lead to strengths and weaknesses. Denim+’ most important strengths are the practical fashion and retail knowledge, large assortment with distinctive products and flexible and ambitious mentality. Denim+’ most important weaknesses are the lack of vision, objectives, strategy and differentiating features, slow online channel development and incompatible channel branding. The external analysis consists of three sections: consumer, competitors and environmental factors also known as trends. These sections issue various threats in the market, Denim+ should not ignore, and opportunities Denim+ could grasp. The media and technology opportunities show chances for Denim+ in the social and mobile media, enhanced by the use of intuitively operable screens and consumer data. The opportunities within the brand and product category show a retail environment based on engagement and interaction. This trend highlights that retailers should offer multiple brands and extend their assortment with non-core products. Mass-customization, self service and providing recommendations are shopping trends giving Denim+ concrete opportunities on how to serve the consumer. The fashion opportunities lie within facilitating consumers need to experiment with look and style, share and DIY fashion. The threats show changing ways of shopping online with high return rates and physical with changing store roles. The growing consumer power through technology shows threats for Denim+ which are: consumers’ ease to find substitute products and suppliers, short attention span and demand for ethically principled brand policies. In the synthesis phase I generated ideas based on search fields coming from the strengths, weaknesses, opportunities and threats. The ideas combined lead to six concepts of which the concept based on product scanning scored the best for integrating the online and physical apparel shopping experience. The final concept is named PLUS, which stands for Personally relevant, Look-based inspirator, User convenient Shopping experience. It clearly describes the goals of the concept. PLUS is based on a mobile application that can read product information. This aspect leads to five new features for the consumer: tangi ble POS material, fitting sessions, smart wish list, online clothing closet and online-only items available in the physical store. Roy Schiet (one of the owners of Denim+ and retail expert) says the concept will be appealing to consumers. This will emphasize that Denim+ is innovative, and creates awareness for the physical store, online and vice versa, which is what this assignment is about.","Multi channeling; Omni channeling; Online store; Physical store; Denim lifestyle; Fashion; Retail; Consumer experience; Shopping experience; Denim+","en","master thesis","","","","","","","Campus only","","Industrial Design Engineering","Design Conceptualization & Communication","","","",""
"uuid:cf4129b2-c598-49e3-9994-78d089a60432","http://resolver.tudelft.nl/uuid:cf4129b2-c598-49e3-9994-78d089a60432","Afsluitdijk project ""The Monument"" location","Liu, S.; Huang, J.; Rayo, S.; Lim, T.Y.","","2012","The Afsluitdijk (Enclosure Dam) is a main dam that forms the fundamental part of the larger Zuiderzee Works that separates the Zuiderzee, a salt water inlet of the North Sea, and turning it into the fresh water lake of the IJsselmeer. It protects the central Netherlands from the effects of the North Sea. It was constructed between 1927 and 1933, and runs from Den Oever on Wieringen to the village of Zurich in Friesland. It is 32 km long and 90 meters wide, rising to 7.25 meters above sea-level, with an incline of 25% on each side. At the location along the Afsluitdijk where the final water passage was closed (‘De Vlieter’), a lookout tower known as ‘The Monument’ was built in 1933. It was presented by the Zuiderzee Works Construction Company and designed by architect W.M. Dudok. The site has a statue of a “Steenzetter”, and also marks the inscription ‘A living nation builds for its future’. A statue of Cornelis Lely has also been erected near Den Oever on the Barrier Dam itself. The Afsluitdijk with The Monument are currently managed by the Ministry of Infrastructure and the Environment (“The client”). There is a restaurant at The Monument where the client has sublet it for private operator to manage it. With the anticipation of increase storm intensity and sea level rise in the future, the client had previously engaged a consultant to analyze the existing design of Afsluitdijk for a design storm of 1:10,000 years. According to the client, the result of the study concluded that the standard cross-section of Afsluitdijk is not sufficient to withstand the design storm of 1:10,000 years, hence, modifications of it are required. The study also found that during the design storm, there is a significant overtopping over the dike. The client is concerned about the significant overtopping found from the previous study may have adverse impact on the non-standard cross-section of the dike where The Monument is located. Therefore, the client has requested our design team to look into the dike section at The Monument location.","afsluitdijk; overtopping; sea defence","en","student report","TU Delft - Section Hydraulic Engineering","","","","","","","","Civil Engineering and Geosciences","Hydraulic Engineering","","","",""
"uuid:d375f685-e9eb-4806-80c2-d6fd39d9ba96","http://resolver.tudelft.nl/uuid:d375f685-e9eb-4806-80c2-d6fd39d9ba96","The touch-enabled mobile interface of the future","Huang, K.","Van Mourik, F. (mentor); Boersema, T. (mentor); Mueller, N. (mentor)","2013","In close cooperation with MobGen, a full service mobile agency located in Amsterdam, this master graduation project aimed for developing an interface style for touch-enabled mobile devices in the time frame of 2 to 3 years. During the process, a calendar app called FluidCalendar, was designed to embody the new interface style that rethinks and reimagines the authentic mobile interaction.","app; application; calendar; touchscreen; iPad","en","master thesis","","","","","","","Campus only","","Industrial Design Engineering","Design for Interaction","","","",""
"uuid:c6295e9d-c40d-445d-98ce-2eee3033ca36","http://resolver.tudelft.nl/uuid:c6295e9d-c40d-445d-98ce-2eee3033ca36","The Upside-Down Publicness","Huang, D.","Marzot, N. (mentor); Komosso, S. (mentor); Fokkinga, J. (mentor)","2014","","Public Realm","en","master thesis","","","","","","","","","Architecture and The Built Environment","Public Building","","Public Realm","",""
"uuid:24eafe6c-1b89-402a-b7cc-4c9903a86dd9","http://resolver.tudelft.nl/uuid:24eafe6c-1b89-402a-b7cc-4c9903a86dd9","Integrating land use conflicts - Resolving conservation and development conflicts through adaptive approach in Northeast Coast National Scenic Area","Huang, N.","Stead, D. (mentor); Nijhuis, S. (mentor); Nadin, V. (mentor)","2014","The research aims to redefine how adaptive planning approach can help traditional spatial planning system to deal with conservation and development land use conflicts through a set of adaptation plans. As most planning system in the world, spatial planning in Taiwan in concerned with both planning making and the control of development (Chen & Shih 2010). Hence, the Northeast Coastal National Scenic Area (NCNSA) Plan is the master plan of the traditional comprehensive model dominating land use and regional planning since 1976. In addition, the designation of slope land in Gongliao (the dominating administrative area of NCNSA) by Rules of Slope-land Conservation and Utilization Act regulated and restricted the built area development. The NCNSA master plan combined with zoning plan reflects the ESAs guidance in regional level and strictly protects landscape from development. As a result, the contradiction areas are mainly overlapped with the settlements in floodplain and mountain villages along Shuangxi River valley. However, the rigidness of land use regulations not only eliminates the possibilities for specific type waterfront development along Shuangxi River valley, but also leads to conflict relationship between the designated conservation areas and the locals. Three research questions will be answered in this study: (1) What are the conservation and development conflicts in case study area? (2) What are the priority spatial development principles? (3) What are the strategies to integrate conservation and development land use conflicts? The research methods include official document review and landscape analysis. A set of adaptation plan will be used to illustrate as development strategy between nature conservation and development. The conclusion will help the completeness of existing local development plan response to national and regional policies as well as local needs.","Adaptive planning approach; conservation and development conflicts; National Scenic Area","en","master thesis","","","","","","","","2014-06-26","Architecture and The Built Environment","Urbanism","","Complex Cities","",""
"uuid:f4d1f651-087f-4afa-977b-4e196ac68eb1","http://resolver.tudelft.nl/uuid:f4d1f651-087f-4afa-977b-4e196ac68eb1","Architecture Anatomy","Huang, H.","Schoonderbeek, M. (mentor)","2014","","border condition","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architecture","","Public Building","",""
"uuid:2232b0cd-47ce-4dd5-b0ed-b8c2d812994e","http://resolver.tudelft.nl/uuid:2232b0cd-47ce-4dd5-b0ed-b8c2d812994e","Recycling Houston: Bringing synergy between improving water safety, reducing energy consumption and reinforcing living quality in suburban","Huang, S.","Meyer, H. (mentor); Tillie, N. (mentor)","2015","The project discusses how the water system can be transformed with integrated (intensification) strategies, in order to improve the three challenges (flooding, urban sprawl and energy consumption) in Houston suburban.","Houston; suburban; flooding; intensification; energy consumption","en","master thesis","","","","","","","","","Architecture and The Built Environment","Urbanism","","Delta Interventions","",""
"uuid:801d9ffa-1c30-4d6e-90cd-f2f1cd0854ae","http://resolver.tudelft.nl/uuid:801d9ffa-1c30-4d6e-90cd-f2f1cd0854ae","Aquaponics DIY in your backyard","Huang, W.Y.","","2015","This ""designers' manual"" is made during the TIDO-course AR0531 Innovation and Sustainability This manual is intended for students who want to create their own aquaponics system. The manual first explains the basics of aquaponics. Followed by a step-by-step construction guide on how to build one yourself.","ar0531 Innovation and Sustainability","en","student report","","","","","","","Campus only","","Architecture and The Built Environment","Architectural Engineering and Technology","","","",""
"uuid:002ee5ed-f355-425c-b871-97c1a055349b","http://resolver.tudelft.nl/uuid:002ee5ed-f355-425c-b871-97c1a055349b","A Scaling-upMethod for Assessing the Impacts of ITS on Traffic Efficiency","Huang, X.","Hoogendoorn, S.P. (mentor); Pel, A.J. (mentor); van Noort, M. (mentor); Annema, J.A. (mentor)","2015","Human beings today have to face a series of problems brought by transport development — severe urban congestion, increasing number of injuries and fatalities as well as global warming caused by excessive emissions. Intelligent Transport Systems (ITS), as effective tools to solve these problems, thus have drawn much attention. In the future, it is expected that more and more ITS would be developed and applied in real practice. Before adopting ITS measures, it is necessary for policy makers to know the impacts of the ITS measure on on a large scale (e.g. national/European level). In many cases, the impacts of ITS are evaluated on a much smaller scale, for example from a microscopic traf- fic simulation or a field experiment. These effects need to be scaled up to the larger scale. There are two known scaling-up methods. The modelling method can accurately represent the large scale scenario, but requires considerable effort and a large amount of data which may not be available. Furthermore, it requires a macroscopic model of the ITS, which may be a challenge to derive. The statistical method describes the local scenarios via situational variables (like road types, vehicle types and traffic situations), classifies the local scenar- ios into categories and calculates the impacts on large scale as the weighted average of the local impacts. This method is easier and faster than the modelling method. However, the statistical method is only applicable for cases which only consider categorical situational variables, because the classification of the local scenarios into categories is not feasible when numerical situational variables are used. As a result, the statistical method is only suitable for ITS whose impacts are on the microscopic mechanisms (e.g speed and headway) and thus mainly affected by categorical situational variables (e.g road type and vehicle type). A scaling-up method to assess the impacts of ITS on traffic efficiency which is generally suitable for all ITS is still missing. To start filling this gap, this study develops a new scaling-up method for ITS that have direct network-wide influences to assess their large-scale impacts on traffic efficiency. The framework of the new scaling-up method is shown in Figure 2.2 and the graphical and mathematical interpretations are presented in Figure 2.3 and Figure 2.4. In brief, the new scaling-up method firstly chooses the suitable indicator of the impacts and situational vari- ables, then collects needed data and builds deterministic relationships between the indi- cator and the numerical situational variables, at last uses scaling sideways to calculate all local impacts and aggregates the local impacts to large scale. From the theoretical perspec- tive, the designed method is considered to be able to evaluate the impacts of ITS measures with direct network-wide influence on traffic efficiency in a large-scale scenario. To provide an evidence of the quality of the new scaling-up method, this study applies it to a specific ITS measure, that is the on-trip dynamic navigation system. Although the final large-scale impacts of the on-trip dynamic navigation system is not calculated due to the limitation of data source, it is proved that the new method is able to accurately assessthe large-scale impacts of the on-trip dynamic navigation system with enough available data. Other findings from the case study are also valuable. For example, the choice of the indicator and the situational variables, and the built deterministic relationship can be directly adopted in other projects that study the impacts of the on-trip dynamic navigation system, which indicates the practical contribution of this study. From a methodological perspective, the new scaling-up method is a great improvement of the current scaling-up approaches. The new scaling-up method expands the applica- tion area of scaling-up methods to ITS that have network-wide influences. Compared to the current methods, the new scaling-up method also improves the accuracy of scaling up and leads to more reliable assessments. Apart from the merits, there are also some dis- advantages of the new scaling-up method, such as the possibility of more time cost and data needed, as well as the possible difficulty to explain the deterministic relationships in a sensible way. The new scaling-up method is regarded to be with significant political value. The out- puts can provide useful information to support policy making. On one hand, according to the political economy model designed by Beuthe, the impacts of ITS play an important role in making policy decisions. The impacts of ITS can directly reflect the perceived effectiveness and the perceived distribution of benefits and costs. On the other hand, based on the outputs of the new scaling-up method, there are also other policy advices that could be made. For instance, the built deterministic relationship(s) can suggest the to-be-set value of the related parameters when adopting a certain ITS measure. For future researches, the attention could be focusing on applying the new method to more ITS measures and investigating the applicability of the new method on assessing the impacts on safety and environment. Specifically regarding the study of the on-trip dynamic navigation system, if the needed data is available, it would be beneficial to conduct a com- plete assessment of the large-scale impacts in a specific scenario in the future. In addition, the influences of other situational variables besides the considered situational variables could also be taken into account. Furthermore, a more specific classification of network structure is expected in future researches.","scaling-up method; impacts of ITS; ITS evaluation","en","master thesis","","","","","","","","","Civil Engineering and Geosciences","Transport & Planning","","Transport, Infrastructure and Logistics","",""
"uuid:5ef1696a-0ef8-4d4c-a807-3d0fd3247b1d","http://resolver.tudelft.nl/uuid:5ef1696a-0ef8-4d4c-a807-3d0fd3247b1d","Design, Analysis and Experimental Evaluation of a Distributed Community Detection Algorithm","Huang, H.","Hidders, A.J.H. (mentor); Krings, G. (mentor)","2015","Complex networks are a special type of graph that frequently appears in nature and in many different fields of science and engineering. Studying complex networks is the key to solve the problems in these fields. Complex networks have unique features which we cannot find in regular graphs, and the study of complex networks gives rise to many interesting research questions. An interesting feature to study in complex networks is community structure. Intuitively speaking, communities are group of vertices in a graph that are densely connected with each other in the same group, while sparsely connected with other nodes in the graph. The notion of community has practical significance. Many different concept and phenomenons in real world problems can be translated into communities in a graph, such as politicians with similar opinions in the political opinion network. In this thesis work, a distributed version of a popular community detection method-Louvain method-is developed using graph computation framework Apache Spark GraphX. Characteristics of this algorithm, such as convergence and quality of communities produced, are studied by both theoretical reasoning and experimental evaluation. The result shows that this algorithm can parallelize community detection effectively. This thesis also explores the possibility of using graph sampling to accelerate resolution parameter selection of a resolution-limit-free community detection method. Two sampling algorithms, random node selection and forest fire sampling algorithm, are compared. This comparison leads to suggestions of choice of sampling algorithm and parameter value of the chosen sampling algorithm.","complex network; community detection; distributed computing","en","master thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","Software and Computer Technology","","Master of Science Computer Science","",""
"uuid:d654771f-bcc8-453b-89f7-d79be5369815","http://resolver.tudelft.nl/uuid:d654771f-bcc8-453b-89f7-d79be5369815","Actuation System Design for a 3 DoF Contactless Wafer Stage","Huang, X.","Van Ostayen, R.A.J. (mentor); Vuong, H.P. (mentor)","2016","Silicon wafers are getting bigger and bigger in the production line, aiming for faster manufacturing, lower cost and higher yield. The handling/transportation technique is becoming more and more critical during the production. As the wafer is being handled with physical contact there is always risk of damage and contemination coming from the contact surface. Contactless wafer stage utilizes a thin film of pressurized air to support the wafer, provides wafer handling without physical contact, hence reducing the risk of damage and contamination. A special contactless 3DoF wafer stage called ""the Flowerbed"" is developed by H.P.Vuong during his PhD research. This flowerbed has a creative mechanical design to combine the wafer support and driving function, so that the wafer can be supported and driven by pressurized air with 3 degrees of freedom (x-y-theta). The goal of this MSc research is to design an actuation system for the Flowerbed, and design a special pneumatic actuator specific for this application. Two actuation configurations are discussed and the concept of 3-RPR parallel manipulator is chosen. Pneumatic actuator is chosen to be the type of actuator in this research. This pneumatic actuator has to be specially made, because the requirement of the actuators is, that it should have a stroke of 80 micro meters, with a maximum force of higher than 140N, and the required bandwidth is 150Hz. Such pneumatic actuator is rarely seen and is not available. A model is developed for this special pneumatic actuator, and is validated by test setups. Further development is made by a design with piezo buzzer. This piezo buzzer is implemented as a low cost valve with high performance, and the use of piezo buzzer makes it possible to integrate the valve into the actuator housing, hence further reduce the cost and improve the performance. A prototype is made to demonstrate the feasibility of such kind of pneumatic actuator. This prototype meets the requirement of the actuator and has very good performance for small range of stroke. However due to the weakness of the pneumatic actuator, the performance of large stroke must be improved. The knowledge developed in this research is summarised as a design method, and a GUI toolbox is made using MATLAB. This toolbox can be used to assist the design of such actuator, reducing the difficulty and provides assist for further research.","pneumatic; actuator; contactless; wafer; stage; piezo; low cost; RPR; valve; orifice; compressed air","en","master thesis","","","","","","","","","Mechanical, Maritime and Materials Engineering","Precision and Microsystems Engineering","","Mechatronic System Design","",""
"uuid:477a5ef8-7f4f-4c72-816e-6258f2cfd395","http://resolver.tudelft.nl/uuid:477a5ef8-7f4f-4c72-816e-6258f2cfd395","Rehabilitation Through Education - a prison in the Garfield Park neighborhood","Huang, J.","Van Bennekom, H. (mentor); Gremmen, B. (mentor)","2016","Reducing recidivism through education programs in the prison.","Garfield Park; Prison; Rehabilitation; Chicago; recidivism","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architecture","","Complex Project","",""
"uuid:ae96c914-17f3-43bd-9203-44b532db51eb","http://resolver.tudelft.nl/uuid:ae96c914-17f3-43bd-9203-44b532db51eb","Wooden shipbuilding school","Huang, D.","Schreurs, E. (mentor); Van Gelderen, M. (mentor); Van der Meel, H. (mentor)","2016","The project is a traditional wooden shipbuilding school for about 200 students includes the craft students in Netherlands and the unemployed residents from the middle class families in the surrounding area of my site. The footprint of the building is about 4000m2, and the total area is 6700m2. It is located at Amsterdam Noord, the district called Buiksloterham.","craft; wooden shipbuilding; quality; uniqueness","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architectural Engineering and Technology","","Interiors","",""
"uuid:7acb210c-a897-4d8a-94db-ef26b519fbdd","http://resolver.tudelft.nl/uuid:7acb210c-a897-4d8a-94db-ef26b519fbdd","The Water Institute","Huang, J.","Palmboom, J. (mentor); Van de Voort, J.A. (mentor)","2016","The design assignment is to design a water institute to use Amsterdam, an international port where talented scholars could gather, to deal with water related issues, especially ones happen in Ijsselmeer. The Water Institute is an educational facility which focus on the sustainable use and management of water resources to support health and prosperous communities. In the same time, public events would be held in the institute to raise the attention of citizens in Amsterdam to the issues mentioned above. With the increasing attention to the Ijsselmeer region, the connection between Amsterdam and Ijsselmeer is hoping to be reactive. In the perspective of architecture, water-related architecture will be explored to strengthen the relation between water and architecture users.","water related design; delta; flood resilience; institute; architecture","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architecture","","","",""
"uuid:731fb6bc-5c1f-42ae-a979-e343d9cabd81","http://resolver.tudelft.nl/uuid:731fb6bc-5c1f-42ae-a979-e343d9cabd81","Magnetic HUB: prototype to shorten the distance between Cd Juarez and El Paso","Huang, X.","Merkeley, T. (mentor); Janusz, S. (mentor); Vollers, K.J. (mentor)","2016","The aim of my project would be using the complex building as the activators for the cities to improve the urban decentralization around the border area.","complex; border; market","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architecture","","","",""
"uuid:9b04a293-c960-43ca-9f3f-8ed966bc0a38","http://resolver.tudelft.nl/uuid:9b04a293-c960-43ca-9f3f-8ed966bc0a38","An Intimate Neighborhood, Care living for Aged People","Huang, Y.","Zeinstra, J.S. (mentor); Alvarez, L. (mentor); Parravicini, M. (mentor)","2016","The purpose of the project is to understand how care is provided to aged people in today’s context, and discuss how care environment should be designed in order to fit in with today’s demands. The intention of design is to create an care living environment that offer several gradients of privacy so that it could suit the need of different aged group. The project also tries to find a proper position to its existing context, the Schilderswijk in Den Haag, by introducing a proper building scale. A passage was also created which links this new project to the existing neighborhood.","eldery home; care architecture","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architecture","","","",""
"uuid:e249abb9-bb0a-4482-aa5d-b5a2ba8b55ab","http://resolver.tudelft.nl/uuid:e249abb9-bb0a-4482-aa5d-b5a2ba8b55ab","Productive & Creative Dalang: towards a strategic framework to integrate urban migrants into industrial upgrading in the periphery of Shenzhen, China","Huang, K.","Sepúlveda Carmona, D.A. (mentor); Calabrese, L.M. (mentor); Koorstra, P. (mentor)","2016","","urban renewal; creative city; urban village; urban migrants; collective factory","en","master thesis","","","","","","","","","Architecture and The Built Environment","Urbanism","","","",""
"uuid:85c3338d-1f39-460a-abd6-bdf58ef52437","http://resolver.tudelft.nl/uuid:85c3338d-1f39-460a-abd6-bdf58ef52437","Personalized adaptive dentist game","Evers, B.; Huang, O.; Starre, R.A.N.","Bidarra, R. (mentor)","2016","The goal of this project was to develop a personalized adaptive game for use at the dentist or other dental treatment settings. Before the project started, a prototype game utilising the Unity game engine was alreadyavailable. The game’s purpose is to make dental treatment more comfortable by playing it during the treatment.Our goal for this project was to transform the existing prototype game into a personalized, adaptive versionof the game. The game experience should vary on the type of player who is playing the game, e.g. withrespect to the difficulty. Furthermore, the game should be playable by a very broad audience: from non-gamers to hardcore-gamers, and from young children to the elderly. To achieve this, we developed a game prototype that uses gameplay characteristics of the player to construct a model representing the player using a set of parameters. This player model is used to construct level generation parameters, which in turn are used by a level generator to generate an appropriate level. To determine what techniques were required to build the game, we conducted research on serious gamingand investigated several methods for player modelling and PCG in games. We found that it is important to keep a player engaged during a serious game in order for the game to have an optimal effect. We also discovered that using an event based player model construction method was the best option for this game. Finally, we chose to use a chunk based level generation mechanism to keep the level generation both varied and easy to control. The game has been tested twice. The first time, at a dental practice with patients of a dental hygienist. The patients found that the game was indeed distracting them from the treatment. The second time, the game was tested at the International Festival of Technology (IFoT) in Delft. Around 40 people played the game and most indicated that they enjoyed the game. However, people were divided on whether the game was challenging. We designed a player model and used it to generate suitable level generation parameters. Also, a controllable level generator was created to facilitate the adaptive experience. The system structure is flexible and allows easy addition, deletion, or modification of system components.","PCG; player model; flow; adaption; distraction; dentist; serious gaming; personalization","en","bachelor thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","Intelligent Systems","","Bachelor Computer Science","",""
"uuid:1684075c-e71c-4a36-94fc-1b328dde0023","http://resolver.tudelft.nl/uuid:1684075c-e71c-4a36-94fc-1b328dde0023","Content Aware Luggage: Enabling Virtual Access to Internal Contents","Huang, D.","Horváth, I. (mentor); de Smit, A. (mentor)","2016","The travel industry has changed a lot since the 1800’s - from ox-wagons, to horse and buggies, to trains and eventually, to airplanes. However, even with the current technology available, suitcases today still mostly focus only on material and structure changes when it comes to improvement. This may improve ergonomics and reliability of the suitcase itself, but it does not aid the user in the process of packing nor informing him/her about the items within the suitcase. By crossing the analog boundaries and entering the digital realm, it gives much possibility in the area of innovation. The result of this project was a concept design of a content aware luggage system, which consists of a technology embedded suitcase and a connected app. NARUS, the content aware luggage, succeeds in providing the user with a more efficient packing and travel experience through the use of cyber-physical systems. The main features of NARUS are: Packing List Generation Item Tracking Virtual Access The “Packing List Generation” feature shortens the planning and packing time for users by automatically extracting data from the user’s flight and hotel information and then generating a packing list based on the user’s previous preferences, duration, weather, and etc. This allows the user to confidently pack, without the unnecessary hassle of spending extra time looking up weather information and calculating how many outfits to bring for the trip. The “Item Tracking” feature uses the cameras embedded in the suitcase and object recognition to check items off the packing list and to remember the contents that were packed for the trip. The feature gives users’ peace of mind that they did not forget anything and that they will not forget anything on the way back. This feature also gives an estimate of the current weight of the suitcase as the user packs. The third feature, “Virtual Access,” allows the user to virtually look into their suitcase with their app. This is done through the 3D depth sensing cameras in the suitcase. This virtual access feature allows the user to travel more confidently and conveniently by giving the option to quickly look on their app to check for items and their location, without opening the physical suitcase. If the user is travelling with more than one suitcase, this feature also allows the user to virtually find things in a suitcase first, preventing them from opening multiple suitcases unnecessarily. User tests show that using this app before looking for an item in the suitcase led to significantly shorter search times.","suitcase; smart luggage; content aware","en","master thesis","","","","","","","Campus only","","Industrial Design Engineering","Design Engineering","","IPD","",""
"uuid:d792916f-fbaa-42a2-af67-4760f0af272d","http://resolver.tudelft.nl/uuid:d792916f-fbaa-42a2-af67-4760f0af272d","Water Valley: Border Water Research Center and Museum","Huang, K.","Merkeley, T. (mentor); Vollers, K.J. (mentor)","2016","","","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architectural Engineering +Technology","","","",""
"uuid:cbec7bdd-4bab-4132-93cd-359587b9bf46","http://resolver.tudelft.nl/uuid:cbec7bdd-4bab-4132-93cd-359587b9bf46","Exploiting Embedding in Content-Based Recommender systems","Huang, Y.","Larson, M.A. (mentor)","2016","XING is a leading career-oriented social networking site in Europe, which usually recommend job ads to their customers. One of the widely used methods in Recomender Systems is content-based filtering, which analyzes the description of item characteristics and the user profile illustrating user's preferences. Due to the sparsity of its dataset, i.e. many job postings are rarely interacted with, XING has been using content-based recommender system to promote the quality of the recommendations. Recent word embedding technique learns semantically meaningful representations for words from co-occurrence in sentences, which enables the effective comparison between words. Based on the Word2Vec technique, XING represents job postings by the average embedding over words they contain. This study explores three alternative methods to represent job postings for the task of recommending jobs to users. In the first experiment, we explore whether the use of a subset of words is more effective to represent the job postings. In the second experiment, instead of averaging over word embeddings, we directly learn document embeddings using Paragraph2Vec. And finally, the third experiment uses Word Mover's Distance to estimate the similarity between job postings. Our experiments show that the embeddings that are learned with Paragraph2Vec result in a better estimation of which job postings are similar, but only when high-dimensional settings are used. The Word Mover's Distance algorithm is computationally expensive, therefore we use existing lower-bounds that allowed us to complete a small-scale experiment within the available time. The results indicate that Word Mover's Distance is not as effective as the average over word embeddings and Paragraph2Vec. In the final part of this thesis, we present the Link2Vec, a novel item representation method based on Word2Vec, which learns semantic representations for items based on the context surrounding the hyperlinks that refer to the item, e.g. hyperlinks to the item's Wikipedia page. Our experiments show that the effectiveness of the embeddings learned with Link2Vec improves with the amount of training data. For the evaluation on the MovieLens dataset, we only obtained a limited set of hyperlinks, which resulted in results that approximate a baseline that uses the average over word embeddings.","","en","master thesis","","","","","","","","","Electrical Engineering, Mathematics and Computer Science","Intelligent Systems","","","",""
"uuid:5b0bfcd4-0cac-462b-8eef-704171cba41c","http://resolver.tudelft.nl/uuid:5b0bfcd4-0cac-462b-8eef-704171cba41c","L‐shaped Connection for Glass Portal Frame: Structural analysis and its application","Huang, W.Y.","Eigenraam, P. (mentor); Bergsma, A.C. (mentor); Louter, P.C. (mentor)","2017","","","en","master thesis","","","","","","","","","Architecture and The Built Environment","Architectural Engineering +Technology","","Building Technology","",""
"uuid:c4051fa6-70e5-4d0b-b510-89e01eca82d4","http://resolver.tudelft.nl/uuid:c4051fa6-70e5-4d0b-b510-89e01eca82d4","Through Stone Frames","Huang, Haiyang (TU Delft Architecture and the Built Environment)","Schreurs, E.P.N. (mentor); Zeinstra, J.S. (mentor); van der Meel, H.L. (mentor); Delft University of Technology (degree granting institution)","2017","This project has studied the different gates of Maastricht, looking for their grammar. The gates have turned into a public colonnade in his building that changes proportion and rhythm as you move through. To give the gates a contemporary form the natural stone has been replaced by precast concrete. The details work as modern ornaments that enhance the spatial experience and give a sense of direction.","Maastricht; material culture; stone","en","master thesis","","","","","","","","","","","","","Maastricht, City of Stone","50.852389, 5.687028"
"uuid:97e6a644-6c3d-48bd-835b-8402203c5377","http://resolver.tudelft.nl/uuid:97e6a644-6c3d-48bd-835b-8402203c5377","Design follows nature: Botanical garden design integrating with biomimetic technology and seismic principles","Huang, Yonghui (TU Delft Architecture and the Built Environment; TU Delft Architectural Engineering +Technology)","Snijders, Anne (mentor); van der Zaag, Engbert (mentor); Jennen, Pierre (mentor); Visscher, Henk (graduation committee); Delft University of Technology (degree granting institution)","2017","The graduation started from the seismic studio of architecture engineering and designing a earthquake proof architecture. The context of the design in located in the historical garden of Uithuizen in Groningen, which is a potential seismic area. The research focuses on the three different aspects which are seismic principles, biomimetic structure and biomimic climate. The final design is attempting to responding to the environmental, historical, social and seismic context with the method which I researched in the first part. The program of my design is a botanical education center for young children in uithuizen. As for technology part, I chose the solar-tracking panels and intelligent light diffusion glass to achieve my final goal: communicating with nature in the ways of architecture and human experience.","biomimectic structure; seismic arhitecture design; sun-tracing louver; botanical garden","en","master thesis","","","","","","","","","","","","","",""
"uuid:18fd54eb-65d0-4999-aa15-3e4c092ee54b","http://resolver.tudelft.nl/uuid:18fd54eb-65d0-4999-aa15-3e4c092ee54b","Transforming Danwei housing: How can the old residential courts from the 1980s to 1990s in Guangzhou respond to diversified demands in urban renewal?","Huang, Xin (TU Delft Architecture and the Built Environment; TU Delft Urbanism)","Qu, Lei (mentor); Harteveld, Maurice (mentor); Delft University of Technology (degree granting institution)","2017","Danwei housing is a typical and common residential type in Chinese cities. The radical social structure changing and urban development after the Economic Reform have influenced these old neighborhoods and even restructured them from all aspects. This thesis has looked into the current social, economic, and spatial transformation surrounding Danwei housing in Guangzhou, analyzed what has been happening, and revealed what driven forces have been embedded in this process. Finally, strategies including institutional suggestions, design principles and test designs are raised.","Danwei housing; urban renewal; industrial transformation; livable city; social changes; Guangzhou","en","master thesis","","","","","","","","","","","","","","113.23, 23.16"
"uuid:dffd6c65-4c06-4c57-ace9-660b7b0440f6","http://resolver.tudelft.nl/uuid:dffd6c65-4c06-4c57-ace9-660b7b0440f6","Complex Project Havana Studio Vedado Group | All for One, One for All: Spontaneous Community Prototype","Huang, Wei (TU Delft Architecture and the Built Environment)","Cournet, Paul (mentor); Mulder, Koen (mentor); Vande Putte, Herman (mentor); Delft University of Technology (degree granting institution)","2017","Cuba is facing badly lack of housing and in the high risk of building collapse. This project is to resolve the issues and stimulate the public life.","Housing; City; every life","en","master thesis","","","","","","","","","","","","","",""
"uuid:6a0cad26-fec1-4329-b408-6e9140573a31","http://resolver.tudelft.nl/uuid:6a0cad26-fec1-4329-b408-6e9140573a31","Flexural behaviour of reinforced concrete beams with a layer of SHCC in the tension zone: Experimental Study","Huang, Zhekang (TU Delft Civil Engineering and Geosciences; TU Delft Structural Engineering)","Hordijk, Dick (mentor); Lukovic, Mladena (mentor); Schlangen, Erik (mentor); Jonkers, Henk (mentor); Delft University of Technology (degree granting institution)","2017","","","en","master thesis","","","","","","","","","","","","","",""
"uuid:17f9df3a-df17-43f3-b92e-eeaf06a6903a","http://resolver.tudelft.nl/uuid:17f9df3a-df17-43f3-b92e-eeaf06a6903a","Multi-way Hash Join Based on FPGAs","Huang, Kangli (TU Delft Electrical Engineering, Mathematics and Computer Science)","Hofstee, H.P. (mentor); Fang, J. (graduation committee); Delft University of Technology (degree granting institution)","2018","The multi-way hash join is one of the commonly used and time-consuming database operations. Many algorithms have been developed to accelerate this operation, some of which use accelerators such as field programmable gate arrays (FPGAs). However, most of the previous work was focused on computation-intensive operations such as (de)compression, because the interface between the FPGA and the host can only provide relatively low bandwidth.\par
However, new generation high-bandwidth, low-latency interfaces to interconnect host processors and accelerators such as the open coherent accelerator processor interface(OpenCAPI) provide FPGAs with new opportunities to accelerate database operations. In this thesis, we explore the potential of using OpenCAPI-attached FPGAs to accelerate multi-way joins. Via the OpenCAPI, the FPGA can obtain a high-bandwidth communicating with CPUs and the main memory at 25.6GB/s. We first investigate the previous research in software-based multi-way joins and observe that this operation is limited by the bandwidth of main memory. Thus, the main challenge of designing the accelerator emerges as avoiding unnecessary memory accesses. We partition the build relations into the size that can build a hash table in Block RAMs (BRAMs), and avoid multiple-pass memory accesses. In our design, the intermediate join phase is pipelined with a partition phase to reduce the size of the intermediate results. The proposed design is configurable for the attached bandwidth, and it can achieve a throughput of 5 GB/s when a 25.6 GB/s bandwidth is provided.","Heterogeneous acceleration; FPGAs; Hash join; Multi-way Join; The relational database; TPC-H; OpenCAPI","en","master thesis","","","","","","","","","","","","Electrical Engineering | Microelectronics","","51.998758, 4.373626"
"uuid:ac890488-730a-4acf-aec9-ddedd18712d2","http://resolver.tudelft.nl/uuid:ac890488-730a-4acf-aec9-ddedd18712d2","Fab-lab Sloterdijk: Customized architecture through digital making","Huang, Leevan (TU Delft Architecture and the Built Environment)","de Koning, S. (mentor); Fokkinga, J.D. (mentor); Have, R. (graduation committee); Delft University of Technology (degree granting institution)","2018","The concept of Fab-lab Sloterdijk is based on increasing the porosity of the border condition of the highway A10, which aims at vitalizing the Ringzone for future economic development of Amsterdam, and empowering the people with tools to make their life. To stitch the disconnection between Amsterdam’s go-to and no-go areas, the design envisions downgrading the ring road and turning exit bypass into bicycle highway – a new frontage of buildings along it. Towards a future of digital production, Fab-lab combines typologies of fabrication workshop and co-working space to provide a platform for sharing economy and open access to knowledge. The project challenges the current model of fabrication that factories are all excluded from the city by bringing fabrication back to a vertical urban factory specializing at prototyping and customization of products. Local production of building material is made possible with integration of robotic arms and 3D printers to fabricate with local collected resource. By doing so, digital construction with recycled resources enables customized architecture and builds towards circular economy. Fab-lab which houses automated digital fabrication will manifest itself through system of digital construction. Empowered by Fab-lab, the future of economy lies in the hands of people, who makes their own city.","Digital architecture; Border condition; Urban intervention; Circularity","en","master thesis","","","","","","","","","","","","","",""
"uuid:681fbba0-2682-45ae-be43-115055b1da4f","http://resolver.tudelft.nl/uuid:681fbba0-2682-45ae-be43-115055b1da4f","Global Housing Graduation Studio: Mixing Mumbai. Affordable Housing for Inclusive Development","Huang, Xiaozhu (TU Delft Architecture and the Built Environment)","Mota, Nelson (mentor); Delft University of Technology (degree granting institution)","2018","","","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences | Global Housing","",""
"uuid:1e6b2745-e539-4752-86f2-ee658ca8222a","http://resolver.tudelft.nl/uuid:1e6b2745-e539-4752-86f2-ee658ca8222a","Spinsight: Fostering Millennial’s Social Vitality At Work","Huang, Min (TU Delft Industrial Design Engineering)","Keyson, David (mentor); Romero Herrera, Natalia (mentor); Werts, Tako (mentor); Delft University of Technology (degree granting institution)","2018","Worldwide, the concept of vitality has been trending and it stands for a positive status of human aliveness and energy correlated with physical and psychological well-being (Ryan & Frederick, 1997). However, vitality in the context of work does not attract much attention and the majority of existing workplace products are productivity-driven for employers’ benefit; this project and its partner OfficeVitae, aim to develop a Vitality Platform to fill in this gap.The project focuses on the millennial employees’ vitality at work as they are becoming the dominant workforce in the near future (Haworth, 2015). Through a series of literature and qualitative user-centric research (contextmapping), a holistic vitality model was formulated including intrapersonal, organizational, contextual and somatic factors. Millennial employees’ vitality at work is fluid and significantly affected by the intrapersonal (e.g. challenge, social interaction, flexibility) and organizational factors (e.g. work-life balance). Work-life balance (harmony) was further identified as the ultimate goal on account of the long-term influence and salient impact on millennial employees. They are seeking the harmony in the fulfillment of work and life achievement (work-life harmony). Then, three vitality directions were formulated accordingly: Pressure Tracker, Macro Management and Life Enrichment. The research phase was concluded with the selected vitality direction “Life Enrichment through drawing new inspirations from colleagues” on account of its positive approach (Social interaction) and the promotion of user agency and mindful person-product interaction (Active participation), which are successful long-term implementing criteria identified from digital health and existing workplace products.In the design phase, four concepts were tested in a Dutch startup company (PHYSEE). The results were accessed by the predefined vitality criteria (e.g. flexibility, social interaction, challenge, relaxation and growth), person-product interaction (Active participation) and the simplicity (Fog, 2009). In addition, the curiosity about colleagues was discovered as a strong intrinsic motivator during the test. Thus, Colleague Observation, answering a non-work-related random question about colleague, was selected for further refinement. Optimized person-product interactions and sustainable motivators (feedback) were explored through iterative research through design. At the end, The Spin Wheel was chosen for optimized interaction and better leveraging motivators (e.g. different difficulty levels of questions). Next, the design goal was reframed -- “A digital platform encouraging millennial employees to explore non-work-related aspects of colleagues with the aim of taking a mental switch from work.”; the interaction should be engaging, curious and relaxed like finding “Where is Waldo?”. The final concept “SpInsight” has three main functions: requesting and answering a random question, proposing a customized question and checking personal record. All the default questions are divided into six categories with different difficulty levels: appearance, belongings, character, experience and customized questions (time-bounded/ non-time-bounded). An interactive prototype was evaluated in four companies. The concept worked in the group of TOPdesk interns and it potentially triggered more face-to-face non-work-related interaction with colleagues, which in turn enhances vitality at work. However, employee participants showed less motivation because of less motivating questions, lack of feedback and trigger. Thus, two focus groups were conducted to clarify the critical long-term motivators. The curiosity about how colleagues perceive oneself was the most powerful spark (Fog, 2009) to enhance the retention (e.g. push notification like “You are mentioned in an answer.”). In general, SpInsight is feasible in a workplace and considered fun and engaging. There are some opportunities could also benefit from its advantage of getting to know people quickly, such as an introduction program in the educational setting. However, how to attract group participation and sustain millennial employees’ interest and motivations over time requires further research and evaluation on different working context (e.g. company scale, department, the stage of group development).","vitality at work; social interaction; positive design","en","master thesis","","","","","","","Campus only","","","","","Design for Interaction","",""
"uuid:fc9a9240-166d-4b90-99dc-98ebb925a4b6","http://resolver.tudelft.nl/uuid:fc9a9240-166d-4b90-99dc-98ebb925a4b6","A Dynamic Multipath File Transfer Engine for Software-Defined Networking","Huang, Yuchen (TU Delft Electrical Engineering, Mathematics and Computer Science)","Kuipers, F.A. (mentor); Delft University of Technology (degree granting institution)","2018","With the fast development of the internet, it is widely expected that data traffic will grow exponentially. To fulfill the internet users’ demand of Quality of Experience (QoE), the way we deal with “the tsunami of data” becomes a big problem. How to transfer data, especially those very big files, as fast as possible can be a very important part of that problem. One promising solution could be using multiple paths instead of a single path transmission. Different conditions on different paths make it difficult to handle multipath transmission well. However, Software-Defined Networking (SDN), a centralized network model, provides new solutions to make multipath transmission possible. In a SDN network, the network status can be monitored. With such monitoring information, an optimal multipath solution can be found to transfer a file as fast as possible.
In this thesis, the optimal multipath transmission problem is studied. The objective is to minimize file transfer time between two end systems in a given SDN network. First, we model this as a linear programming problem on a time-expanded network. The time-expanded network used makes that the complexity of this solution is pseudo-polynomial. From this solution, we are able to derive a Fully Polynomial-Time Approximation Scheme (FPTAS) where we can accurately control the speed versus accuracy tradeoff. Lastly, we have build an SDN-based proof-of-concept implementation through which we have evaluated our two algorithms.
As employed today, optogenetics requires methods for guiding sufficiently strong and precisely timed light to specific brain regions, while the experimental subject carries out behaviors of interest. For this role, miniaturized devices (namely optrodes) shall be properly engineered to hold the required components (e.g. light source, recording electrodes, etc) whilst complying with some surgical and biocompatibility issues.
In this work, an optrode was designed and fabricated using an in-house MEMS microfabrication technology. The custom-made device featured (a) low impedance level with TiN-coated microelectrodes, (b) sufficient optical power delivery through on-chip-uLEDs, and (c) miniaturized dimensions with tolerable tissue damage during long-term animal experiments. In addition, different optrodes were fabricated to allow different experiment conditions (i.e. chronic or acute implantation, multi-site or multi-layer studies). A MEMS cavity for the on-chip-uLED was engineered on the optrode's shaft in order to further minimize the induced tissue damage during the surgical implantation. Last but not least, this customized optrode is also compatible with our in-house CMOS technology and can be further upgraded with additional electronic functionalities, as well as with the deposition of novel materials.
After the microfabrication and system integration, in-vitro experiments on three different designs were performed to characterize electrically the electrode impedance, the control of uLED's light intensity and pulse frequency.","Optrode; Optogenetics; Electrophysiology; MEMS technology; Micro-LED; Microelectrodes; Microfabrication","en","master thesis","","","","","","","","","","","","","",""
"uuid:6d8fe884-740a-4947-8974-12d6f0237394","http://resolver.tudelft.nl/uuid:6d8fe884-740a-4947-8974-12d6f0237394","Enabling Human Computation through Text-based Conversational Agents","Huang, Owen (TU Delft Electrical Engineering, Mathematics and Computer Science; TU Delft Software Technology)","Bozzon, Alessandro (mentor); Mavridis, Panagiotis (mentor); Houben, Geert-Jan (graduation committee); Urbano Merino, Julian (graduation committee); Delft University of Technology (degree granting institution)","2018","Human Computation (HC) has established itself to be a powerful tool for carrying out certain simple and repetitive tasks in the form of microtasks, which to this day are still difficult for a machine to automate.
With the latest increase in interest in machine learning, HC has similarly gotten more attention as a popular way to acquire training data in large quantities.
Traditional microtask crowdsourcing platforms, such as Amazon Mechanical Turk (AMT) or Figure Eight, are typically built using web-based interfaces.
However, the speed and quality of data acquired via the crowd are naturally limited by the number of available workers and their skill set.
We perceive a grand opportunity in expanding the crowd by exploring alternative means to the traditional microtask crowdsourcing platforms that are reliant on the web-based interface.
More specifically, as popular messaging services such as Telegram, WhatsApp and Facebook Messenger are used on a daily basis by millions of people across the world, we propose to perform HC activities inside these services through a text-based conversational agent (or chatbot).
We foresee new opportunities arising in conducting HC inside the chatbot, that could leverage the access to a potentially larger and more diverse crowd.
In this thesis, we set the first step towards a new alternative to the typical web-based interface used in HC.
As a result, we set out to investigate the viability of facilitating microtask crowdsourcing inside chatbots.
To this end, we design and implement a chatbot that acts as a medium for the execution of microtask crowdsourcing activities, which is then used for conducting several pilot experiments.
In addition, we propose a mapping from Web to Chatbot tasks for several commonly found User Interface (UI) elements inside worker interfaces.
Thereafter, we conduct an elaborate experimental campaign to gauge the feasibility and interest of crowd workers to use the chatbot as a new medium for performing generic microtasks.
We designed, implemented and executed six common microtask crowdsourcing types; Information Finding, human OCR (CAPTCHA), Sentiment Analysis, Object Labelling, Image Annotation, and Speech Transcription.
For each task type, we implemented a microtask in both a web-based and conversational interface.
By measuring the execution time, quality of answers and surveying workers’ satisfaction of a total of 316 distinct workers recruited via Figure Eight, we show that chatbots can be effectively used as an alternative to the web-based interface to perform microtask crowd work.
We report that out of all workers who participated in the chatbot tasks, 98.3% of the workers indicated a positive experience and were satisfied with their interaction with the chatbot, while performance in terms of task execution time and output quality was in general comparable.","Chatbots; Human Computation; Conversational Agents; Microtask Crowdsourcing","en","master thesis","","","","","","","","","","","","Computer Science | Web Information Systems","",""
"uuid:95f9e5b9-1ab2-4b7d-bb0e-727d4573f432","http://resolver.tudelft.nl/uuid:95f9e5b9-1ab2-4b7d-bb0e-727d4573f432","Punctuation in Teusaquillo: Chair of Methods and Analysis Studio Positions in Practice","Borczyńska, Ksymena (TU Delft Architecture and the Built Environment); Çakir, Ege (TU Delft Architecture and the Built Environment); Gołębiewska, Emilia (TU Delft Architecture and the Built Environment); van der Heide, Iris (TU Delft Architecture and the Built Environment); Huang, Danlei (TU Delft Architecture and the Built Environment); Kao, Hsuanya (TU Delft Architecture and the Built Environment); Lam, Hiu Ching Debby (TU Delft Architecture and the Built Environment); Leone, Silvia (TU Delft Architecture and the Built Environment); Leung, Cherk Ga (TU Delft Architecture and the Built Environment); Logotheti, Ilianna (TU Delft Architecture and the Built Environment); Lopes Cardozo, Rebecca (TU Delft Architecture and the Built Environment); Panasiuk, Agnieszka (TU Delft Architecture and the Built Environment); Peluffo Navarro, Miguel (TU Delft Architecture and the Built Environment); Petrounine, Alexander (TU Delft Architecture and the Built Environment); Rossoni, Elena (TU Delft Architecture and the Built Environment); Słopnicka, Julia (TU Delft Architecture and the Built Environment); Stubbs, Robby (TU Delft Architecture and the Built Environment); Ulbrich, Isabel (TU Delft Architecture and the Built Environment)","Havik, K.M. (mentor); Mejia Hernandez, J.A. (mentor); Altes Arlandis, A. (mentor); Delft University of Technology (degree granting institution)","2019","","","en","student report","","","","","","","","","","","","Architecture, Urbanism and Building Sciences | Methods and Analysis | Positions in Practice","",""
"uuid:2bc14761-3800-4315-aa7b-0455b7e393cf","http://resolver.tudelft.nl/uuid:2bc14761-3800-4315-aa7b-0455b7e393cf","Machine Learning Based Error Modeling for Surrogate Model in Oil Reservoir Problem","Huang, Jie (TU Delft Electrical Engineering, Mathematics and Computer Science)","Lin, Hai Xiang (mentor); Heemink, Arnold (graduation committee); Cai, Juan Juan (graduation committee); Delft University of Technology (degree granting institution)","2019","This thesis focuses on the construction and optimization of a prediction model for the errors resulting from a model order reduction (MOR) procedure in oil reservoir simulation. MOR is a numerical technique that projects the physical based model, which is also called the high-fidelity model (HFM), into a lower dimension by using matrix decomposition, such that the computational speed can be greatly increased. The reduced order model (ROM) is also known as surrogate model. Obviously, error occurs during the projection process. We want to estimate this error and predict it through building an error model, and to fortify the surrogate model by adapting a parameter estimation. In this thesis, three statistical methods will be adapted to our problem, including least absolute shrinkage and selection operator (LASSO) and two machine learning (ML) methods: long short term memory (LSTM) and fully-connected recurrent neural network (RNN). The training data is the error of the ROM, which is defined as the difference between the ROM values and HFM values. Efforts have also been made to improve the performance of the error model, including the pre-processing of the data, and several model optimization techniques. The model order reduction method here is a non-intrusive subdomain POD-RBF algorithm, which treats subsurface oil-water flow data by adapting domain decomposition (DD), radial basis function (RBF) and proper orthogonal decomposition (POD). The high-fidelity model is generated by Matlab reservoir simulation toolbox (MRST). The error is defined as the difference between the HFM data and the ROM data. Through the comparison of several statistical models, this error can be best predicted by an optimized traditional recurrent neural network.","","en","master thesis","","","","","","","","","","","","Applied Mathematics","",""
"uuid:89facd19-09df-4e29-8c65-aa226ccb7c26","http://resolver.tudelft.nl/uuid:89facd19-09df-4e29-8c65-aa226ccb7c26","Naturally, a port city often shrinks: Nature-based adaptation for Wadden Sea Den Helder coast","Huang, Huang (TU Delft Architecture and the Built Environment)","Hooimeijer, F.L. (mentor); Kuzniecow Bacchin, T. (graduation committee); Delft University of Technology (degree granting institution)","2019","The North Sea has played an important role in European urbanization. Coastal cities thrive on the basis of port economy; but also shrink significantly once the dominated industry recessed. Today, under the threat of climate change, port-dominated homogenous development becomes rather vulnerable to disturbances. Den Helder is the Wadden port-city encountering severest shrinking rate. It is particularly sensitive to environmental change and economic shift, regarding to coexistence of tidal ecosystem protection, maritime activities and rising flood risk. To facilitate reciprocal collaboration between ecosystem and economy, the project explores ‘Nature-Based Solutions’ as an integrated coastal zone management approach for interdisciplinary risk adaptation. In design fiction workshop, a catastrophic 2053 flood is fabricated to facilitate local imaginations on a more nature-based future. Qualitative narratives were structured into a prospective Building-with-Nature scenario, challenging the Business-as-Usual projective scenario. Through backcasting, an adaptive pathway for current shrinking Den Helder is proposed, comprising three strategic phases: utilize, guide and oppose according to risk index. The spatial design employs these strategies in two transformation cores: port-front residential and suburban agricultural polders. By reusing existing canal system to deliver tidal ecosystem services, this backbone synergizes a holistic regeneration that aligns to conserve-release-reorganize natural adaptive cycle. An integrated package is proposed, combining technical renovation of houses, de-polders and a PPP insurance model to incentivize participation and to share the risk. The project is concluded with an open-ended scheme in which shrinking is addressed as part of natural secession. Sequence of actions are suggested based on economic vitality and capacity of ecosystem services.","Nature-based Solutions; Urban shrinkage; Den Helder; design fiction; Wadden Sea; Urban transformation; Integrated Coastal Zone Management Colombia; GeoDesign","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences","D-i 2017-2018 Studio – North Sea: Landscapes of Coexistence",""
"uuid:b8545f7a-6eb5-45b6-963b-1fd907130f73","http://resolver.tudelft.nl/uuid:b8545f7a-6eb5-45b6-963b-1fd907130f73","Feasibility Study of Driverless Maintenance in Highway Construction Zones","Huang, Ziye (TU Delft Civil Engineering and Geosciences)","van Arem, B. (mentor); Farah, H. (mentor); Annema, J.A. (mentor); Elbersen, Bert (mentor); Delft University of Technology (degree granting institution)","2019","Highway construction zones post a danger to both road workers and road users because of the change of road condition and speed variance. Driverless maintenance is expected to improve traffic safety by removing road workers from work zones. This study investigates the feasibility of implementing driverless maintenance in dynamic highway construction zones, including the stakeholder involvement, traffic impact analysis and cost-benefit analysis.","","en","master thesis","","","","","","","","","","","","Civil Engineering | Construction Management and Engineering","",""
"uuid:0a49762c-0d65-46d3-bce7-9097f352924b","http://resolver.tudelft.nl/uuid:0a49762c-0d65-46d3-bce7-9097f352924b","From Boundary to Border: Toward a resilient, dynamic and interactive urban edge of Northwest Miami","Huang, Cai (TU Delft Architecture and the Built Environment)","Nijhuis, S. (mentor); Lub, M. (graduation committee); Delft University of Technology (degree granting institution)","2019","On the northwest urban edge of Miami Dade County, the mining industry of the largest scale in Florida has existed for over 60 years. However, it is estimated to stop by 2050 as the reserves decline. As a consequence of limestone mining, more than 10,000 hectares of abandoned lakes will be left on the landscape. This project proposes land and water strategies to guide the future development of this post-mining lake area. It starts from the analysis on the existing hydrological, ecological, urban and mining conditions and define the existing situation as “boundary” that tends to establish static binary opposition between the urban and nature systems. Based on the site context, it proposes and explores “border” as a new urban edge condition that presents a dynamic interactive process in time. This process not only provides the possibility of regenerating potential of the post-mining area, but also increases resilience of the water system. What’s more, it creates conditions for the nature and urban systems to interact with each other and develop into an integrated whole.","Landscape urbanism; Landscape architecture; Landscape Approach; urban edge; mapping","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences","",""
"uuid:2488dcae-c7a6-4083-ad35-c58b106a9548","http://resolver.tudelft.nl/uuid:2488dcae-c7a6-4083-ad35-c58b106a9548","Living Together: Design a Parisian Neighbourhood both for Tourists and Residents","Huang, Wanying (TU Delft Architecture and the Built Environment; TU Delft Urbanism)","van den Burg, L.P.J. (mentor); Romein, A. (graduation committee); Delft University of Technology (degree granting institution)","2019","How to improve the residents living quality while developing tourism in a historical inner city neighbourhood? With its profound historical development and events, Paris has been shaped as a super glorious political centre, the most attractive tourist destination and the most beautiful city in the world. The tourism industry promised the preservation and gentrification of such neighbourhoods, such as Le Marais (Djirikian, 2004), while the over development of the tourism industry has become a problem for resident living quality in these neighbourhoods. The project conducts research into the problems caused by tourism development in an historical inner city neighbourhood in Paris. The aim of this study is to exterminate the coherence and incoherence of residents and tourists’ spatial demands, thus identify the essential spatial qualities related to the needs and behaviours of tourists and residents, at the end provide design proposals which improve the living quality of residents while developing tourism properly on the site. It is a guideline for design interventions in a historical and tourist neighbourhood in the inner city of Paris, moreover for the neighbourhoods that are confronting similar issue.","Tourism; Historical City Center; Liveability; Social sustainability; Urban design","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences","","48.8848, 2.337859999999978"
"uuid:6edb3603-31e3-4c21-8fed-774bc4ea54d4","http://resolver.tudelft.nl/uuid:6edb3603-31e3-4c21-8fed-774bc4ea54d4","Port of Rotterdam Intertidal wetland: Final Report","Bushell, Terry (TU Delft Civil Engineering and Geosciences); Jin, Yueyuan (TU Delft Civil Engineering and Geosciences); Huang, Haoxi","Delft University of Technology (degree granting institution)","2019","The Port of Rotterdam has many old harbours located close to the Rotterdam city center that are no longer suitable to be used for industrial purposes. Meanwhile due to expansion and population growth of the city, more recreational spaces are needed. The idea is to use the abundant dredged material from the Port of Rotterdam to fill in and construct intertidal wetland parks in some of these old harbours. They will serve as natural habitats for different types of flora and fauna such as migratory birds. These intertidal parks are also ideal recreational spaces for residents. This multidisciplinary project aims to provide a conceptual design of a tidal wetland in the Maashaven harbour. In this report, a general design is presented, and special attention is paid to technical issues that may occur in the construction process.","dredged sediment consolidation; wetland construction; conceptual design","en","student report","","","","","","","","","","","","","MDP291",""
"uuid:caa5dc7e-ad97-4c2c-827a-7019cdc56390","http://resolver.tudelft.nl/uuid:caa5dc7e-ad97-4c2c-827a-7019cdc56390","Analysing the polarisation sensitivity of the Near Infrared Spectrograph on board the James Webb Space Telescope","Huang, Jeffrey (TU Delft Aerospace Engineering)","Stam, D.M. (mentor); van der Wal, W. (graduation committee); Endo, A. (graduation committee); Giardino, G. (graduation committee); Ferruit, P. (graduation committee); te Plate, M.R.J. (graduation committee); Delft University of Technology (degree granting institution)","2019","The objective of this master thesis research project is to determine the overall polarisation sensitivity of the Near Infrared Spectograph (NIRSpec) on board the JamesWebb Space Telescope (JWST). Understanding the polarisation sensitivity is important to correctly interpret the output data and accurately calibrate the instrument during operational lifetime. As experimental research on this topic for NIRSpec was limited, a numerical code has been built to simulate the light following the optical path of NIRSpec. This numerical code is effectively a ray tracer with polarisation state analysis functions. They ray tracer is designed to be modular, making it straightforward to add new functions or optical elements, either for future work on NIRSpec or application to other instruments. The analyses regarding the polarisation sensitivity were performed in three main categories: the induced polarisation through reflections by mirrors, the grating efficiencies and overall throughput, and the effect on the calibration process. The JWST is a large space telescope that aims to help better understand every time period of the universe from the Big Bang till the present. The launch is currently scheduled in March 2021. The JWST shall provide new data by observing thermal radiation from various celestial objects. It houses four main science instruments, one of which is NIRSpec developed by the European Space Agency. The optical design of NIRSpec is based on three three-mirror anastigmats and six main opto-mechanical assemblies. Two of those assemblies are the grating wheel assembly which houses dispersive reflection gratings and the calibration assemblywhich is used to internally calibrate the instrument. These optical elements introduce a polarisation sensitivity, meaning that the instrument output data will depend on the polarisation state of the incoming radiation. Even though NIRSpec will mainly observe unpolarised light sources, a degree of polarisation will always be induced via reflections by themirrors. The optical path of the calibration beam differs from the nominal science path, so a different degree of polarisation will be induced via the calibration path compared to the nominal science path. Application of the calibration measurements to the science measurements can thus lead to errors on the deduced signals. The induced degree of polarisation for the nominal science path will likely remain below 2%. This degree of polarisation is slightly dependent on both wavelength and initial incidence angle, but not significantly. The analysis of the grating efficiencies clearly indicates a polarisation sensitivity up to 20% for the medium resolution gratings and up to 40% for the high resolution gratings. Due to the low estimated induced polarisation below 2%, the maximumuncertainty in the output data for unpolarised incoming light would be lower than 1%. Observing celestial objects with an inherent degree of polarisation, however, could introduce a significant uncertainty in the measurements. Finally, the calibration process has also been examined and it can be concluded that the induced degree of polarisation by the calibrationmirrors before the light reaches the grating will be 1 to 2% higher compared the nominal science path. Whether or not this difference should be taken into account will depend on the application. Recommendations for future work can be divided into four categories. First, the reflection grating efficiencies should be analysed in more details as the accuracy of the presented results is uncertain. Second, the filters and detector are modelled as single layer Fresnel surfaces, while in reality they consist of multiple layers of different materials. It should be researched how this assumption affects the presented results. Third, configurations using the long-slit spectroscopy and integral field spectroscopy have not been analysed while the microshutter assembly is modelled as ideal transmitter. Analysing these configurations would provide a more complete understanding ofNIRSpec’s polarisation sensitivity. Fourth, validation through measurement data would help determine the accuracy of the ray tracer presented in this master thesis research. This data could come from eithermeasurements of NIRSpec during operational lifetime or comparable instruments of which measurement data is available.","","en","master thesis","","","","","","","","","","","","Aerospace Engineering","",""
"uuid:6d09d700-2958-45ab-8952-18460852885f","http://resolver.tudelft.nl/uuid:6d09d700-2958-45ab-8952-18460852885f","Reinventing the (green) strips: An investigation on urban in-betweenness","Huang, Danlei (TU Delft Architecture and the Built Environment)","Mejia Hernandez, Jorge (mentor); Jennen, Pierre (graduation committee); Havik, Klaske (graduation committee); Delft University of Technology (degree granting institution)","2019","The green strips can be found in many roads/streets in Bogota as an urban infrastructure for dividing vehicles and traffic. However, on top of this regulating function, it can be observed that the citizens of Bogota have the tendency to spontaneously appropriate the green strips in ways that’s convenient for them.","Bogota; public space; strip; Intervention; in-betweenness","en","master thesis","","","","","","","","","","","","","",""
"uuid:a84b29d0-24d8-413e-be91-07377cc4ef24","http://resolver.tudelft.nl/uuid:a84b29d0-24d8-413e-be91-07377cc4ef24","Open Construction: Envisioning a network for construction circularity in an urbanising landscape in the province of South Holland","Carvajal Ordonez, Nicolas (TU Delft Architecture and the Built Environment); Conijn, Laura (TU Delft Architecture and the Built Environment); Hanse, Christiaan (TU Delft Architecture and the Built Environment); Huang, Yixiang (TU Delft Architecture and the Built Environment); Ruiz Carvajal, Federico (TU Delft Architecture and the Built Environment)","Dabrowski, M.M. (mentor); Rooij, R.M. (mentor); Forgaci, C. (mentor); Delft University of Technology (degree granting institution)","2020","A nationwide program for building one million dwellings aims to relieve the Netherland’s housing crisis: nearly a quarter of this construction will take place in South Holland. Currently, the construction industry needs a huge input of raw materials that is not only causing waste problems but is also decreasing environmental quality. A large part of construction and demolition waste (CDW) is being downcycled, losing economic and material value. This creates not only a need but an opportunity for a construction and demolition (C&D) industry based on circular flows and biobased materials. The goal of this project is to produce a vision with strategies for the implementation of circularity along with the resolution of spatial conflicts in different scales.An overview of the spatial, technical and economic needs of the C&D industry and its externalities in urban environments was made. This resulted in the understanding of the spatial conflicts currently taking place between these two spheres of development and the potentials that circularity will have on jobs and consumption patterns. From this, a proposal for a circularity model with three components was formulated: an open network with a central production hub and peripheric logistic hubs, an open program for these hubs that adapts to current and future needs, and open edges that create interactions with their built and social environment.","Province of South Holland; circular economy (CE); construction and demolition waste; construction hub; open scales; urbanisation","en","student report","","","","","","","","","","","","Architecture, Urbanism and Building Sciences","AR2U086 R&D Studio – Spatial Strategies for the Global Metropolis",""
"uuid:1461f4da-8cd4-4dc9-8d7e-6e38fffa9c10","http://resolver.tudelft.nl/uuid:1461f4da-8cd4-4dc9-8d7e-6e38fffa9c10","A Cluster Scale Decentralized Water Management System","Huang, Hongjie (TU Delft Architecture and the Built Environment)","Smit, Mo (mentor); Tsui, Tanya (mentor); van der Zaag, Engbert (mentor); Delft University of Technology (degree granting institution)","2020","Water is one of the long-standing problems in Sint Maarten. Water supply is scarce while water demand is high. Water pollution and incomplete infrastructure also needs to be tackled. How can a cluster scale decentralized water management system solve water challenges in the hurricane-prone environment of Sint Maarten is the research question. This paper answers this question from the following aspects. First, an analysis of existing water consumption amounts, water management systems, and water flows. Second, a case study of water management systems in other countries and regions, combined with a literature review to analyze how each system works. Third, develop a set of evaluation systems and analyze and evaluate each case. Then choose a new water management system for the Sint Maarten.","Decentralized water management system; circular housing cluster; water supply; greywater purification; wastewater treatment; community reactivation","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences | Building Technology | Sustainable Design","",""
"uuid:7b960d1e-6549-4b4c-b3ed-2ff41f3ff6f6","http://resolver.tudelft.nl/uuid:7b960d1e-6549-4b4c-b3ed-2ff41f3ff6f6","Design for future DDL workplace","Huang, X. (TU Delft Industrial Design Engineering)","Desmet, P.M.A. (mentor); Jaskiewicz, T.J. (mentor); Delft University of Technology (degree granting institution)","2020","A physical work environment is essential for creating and supporting different activities in the workplace, not only for work performance but also for physical and mental wellbeing. Studies have been conducted on the influence of the working environment on work performance and people’s wellbeing since the 1950s. Most of these studies have been published in the domains of ergonomics and human factors or in historical papers on the office environment (Katja, 2019). In recent years, motivated by increasing demand for wellness-focused design, companies and organizations are putting more effort into investing in properties that improve employee’s performance while enhancing their wellbeing in the workplace (Zack, 2019), exploring opportunities of new emerging technologies. The same applies to universities where they always seek for new approaches. Students are more willing to adapt to changes and to participate in experimental setups. Delft Design Labs offers multiple opportunities for student participation and master thesis project is one of them. Working on a graduation project is a challenging time and a graduation lab workplace should be an environment that can help. This project is focused on designing for the future Delft Design Labs workplace, which is being used by students who are working on their graduation projects for Delft Design Labs. The final design is a product system called ""Hexabond"" which encourages meaningful interactions between students, without disturbing everyone. It gives the user an opportunity to connect and interact with others, which can be a start point for students to get to know each other. The Hexabond is simple to set up and does not require a precious time investment. The aesthetic of the products is simple and minimalistic and makes it fit into any workplace. For validation of the Hexabond, some prototypes were created for user tests. The results of the test showed that the final design met the design goals well. The resulting product fulfills the need for encouraging students to offer and ask for help in the workplace, creating connections between students and making students feel a sense of belonging. However, there is still room for improvement for maintaining the connections between students. The biggest limitation during the project is the unfortunate pandemic. Making it impossible to do user tests in the DDL workplace or in general. The current design is still rather hypothetical and is not fully validated with the right usage. The product is rather a user-centered design that needs input and feedback from the user group. If it was possible to actually test the product in a shared workplace with the students, it would have yielded insightful feedback for iterations.
The first research question is to identify what factors contribute to the cold start. We first learn lessons from research on cold start in Serverless and examine the current service auto-scaling process powered by Horizontal Pod Autoscaler (HPA), then suggest five hypothetical factors that may affect cold-start performance. Our findings indicate that reactive autoscalers like HPA are dilatory in determining scale events and lack a coordination mechanism to scale correlated workloads in sync. Besides, different programming languages differ in code loading and execution time. The major factors lie in slow scale decision making and application code loading. In contrast, other factors such as cluster size, the choice of container runtimes and CNI network solutions are negligible.
In the next two research questions, we investigate how to mitigate cold start and how effective the proposed solutions are. Based on our study from the first research question, we conclude that extra efforts must be made to speed up scaling decision-making and reduce application startup time. We compare a few technical solutions to the hypothetical factors. According to the results, we encourage microservice application developers, especially Java developers, to try and test different programming language stacks, preferably Go, for rapid auto-scaling. In addition, we propose a coordinated horizontal pod autoscaler, named CHPA, a supplement to HPA, allowing a group of identified, correlated scale targets to scale out in sync, rather than each making independent scaling decisions. As a result, no laggard pod in the auto-scaling process, thereby mitigating the cold start problem holistically.","Kubernetes; Auto-scaling; Microservices","en","master thesis","","","","","","","","","","","","Computer Science","",""
"uuid:7b7ab297-e97f-4c42-9f4f-48b694172e09","http://resolver.tudelft.nl/uuid:7b7ab297-e97f-4c42-9f4f-48b694172e09","Finding Core-periphery Structure in Directed Networks: An Algorithm for Detecting Multiple-group Core-periphery Structure in Directed Netwoks","Huang, Hao (TU Delft Electrical Engineering, Mathematics and Computer Science; TU Delft Network Architectures and Services)","Kooij, R.E. (mentor); Dubbeldam, J.L.A. (graduation committee); Delft University of Technology (degree granting institution)","2021","The core-periphery structure is a mesoscale topological structure that refers to the presence of a dense core and a sparse periphery. The core-periphery structure has been discovered in financial, biological, and technological networks. Various methods for detecting core-periphery structure have been proposed, exploring different discrete or continuous models and single or multiple core-periphery groups. A method that implements multiple-group detection and edge-direction dependency to core-periphery detection is yet to be researched. This report proposes an algorithm to extract the core-periphery structure that satisfies multiple-group and edge-direction dependency requirements. This algorithm features a heuristic process and can process a large-scale network in an acceptable amount of time. Details of the theory behind the proposed algorithm are presented. The algorithm is tested on synthetic, random scale-free, and sampled dark web networks to verify the basic and advanced feasibility. Finally, in-depth analysis with the knowledge of core-periphery structure on a large-scale dark web network sample is presented.","Graph theory; Heuristic; Core-periphery Structure; Directed graph","en","master thesis","","","","","","","","","","","","","",""
"uuid:6f924cd6-7806-4eab-b68a-48d9ce081409","http://resolver.tudelft.nl/uuid:6f924cd6-7806-4eab-b68a-48d9ce081409","Recognition of CRISPR mutational signatures using matrix factorization methods","Huang, Olivia (TU Delft Electrical Engineering, Mathematics and Computer Science)","P. Gonçalves, Joana (mentor); Delft University of Technology (degree granting institution)","2021","Motivation: As one of the most common and life-threatening diseases in humans, cancer is a result of the accumulation of somatic mutations throughout the life cycle. Somatic mutation is a joint result of DNA lesion, which is a result of damage on DNA caused by mutagen, and the failure of DNA repair mechanisms. Therefore, understanding the mechanism of DNA repair is important for the development of cancer pathology. Research on mutational signatures in cancer genomic data has given us insights into the relationship between DNA repair pathway and certain types of cancer. However, close-up studies on DNA repair pathways still need to be carried out to understand repair behaviour further. The CRISPR-Cas9 technique can create double-strand break in DNA. This paper extracts mutational signature to observe the characteristic of the pathway for the CRISPR-mediated double-strand break repairing in order to obtain a deeper understanding on DNA repair mechanisms.
Results: By analyzing the mutational signature extracted from CRISPR-Cas9 mediated targets, we found out that the mutational processes involved in double-strand break DNA repair processes are simple and predictable compared to mutational processes involved in the formation of cancer cells. When comparing the mutational processes in wildtype and cNHEJ-deficient cells, the latter show a much higher frequency of micro-homology related deletions. However, no significant difference between the two types of cells on the mutational process is able to be captured by the mutational signature extraction algorithm. The experiments also show that the selection of mutational features could significantly influence the final signature extraction results.","mutational signature; DNA repair; CRISPR-Cas9","en","master thesis","","","","","","","","","","","","","",""
"uuid:d846c788-8f8c-489b-b354-b25b0a1bf2d0","http://resolver.tudelft.nl/uuid:d846c788-8f8c-489b-b354-b25b0a1bf2d0","An extended multiphase drift-flux model with a discretized form of population balance equations for flocculation and settling process of cohesive sediment in deep-sea mining plumes","Huang, Ziyang (TU Delft Mechanical, Maritime and Materials Engineering)","Helmons, R.L.J. (mentor); Keetels, G.H. (mentor); Elerian, M.F.A.I. (mentor); Breugem, W.P. (graduation committee); Chassagne, C. (graduation committee); Delft University of Technology (degree granting institution)","2021","To meet energy demand towards a low-carbon future, the global market demand is growing for metals such as cobalt and nickel which are major elements in batteries. Polymetallic nodules, which are formed on abyssal plains at depths ranging from 4 to 6 kilometres and are distributed in high abundance on the top of the seabed, contains several times more cobalt and nickel than the entire global terrestrial reserves. This has raised the interest to exploit these resources from the deep ocean. The seafloor mining tool (SMT) can move along the soft sea bottom and can collect polymetallic nodules. While doing so, it will also entrain sediments and water. The excess of water and sediment entrained is discharged at the back of the SMT, forming a sediment plume. The sediment plume dispersion has strong adverse impacts on deep-sea environment.Thus, it is essential to study the sediment plume behavior in order to limit plume dispersion and thus to reduce its environmental impact.
Experimental research is a powerful technique to study the plume behaviour. However, experiments sometimes take a long time due to complex set-up. In comparision, numerical analysis can save time and costs when solving complex problems. Furthermore, numerical modelling can provide deeper understanding and flexibility for boundary conditions and sediment types, which is applicable on both model and prototype scale. Previous numerical studies have noted the significant role of flocculation in limiting plume dispersion, but flocculation process has not been modelled explicitly. This study aims to establish a numerical model to study flocculation process and its effect on sediment transport.
Previous flocculation-fluid dynamics modelling has applied a Euler-Euler method with additional population balance equations. The disadvantage is that many equations need to be solved. To avoid excessive computational costs, the sediment transport is described by a multiphase drift-flux model in this study. The flocculation process is modelled by a discretized form of population balance equations. The author has found that, by multiplying the particle volume, the population balance can be efficiently incorporated in the phase continuity equations in the drift-flux model. The population dynamics of particle aggregation and breakup can thus be characterized by the phase transition terms in the phase continuity equations. Hence, no additional equation needs to be introduced and solved.
Verification is carried out to check conservation relationships and iterative convergence of numerical results. Then, an initial numerical investigation has shown the results can qualitatively show the three settling stages (i.e., flocculent settling, hindered settling and compression settling) found in the experimental studies. Afterwards, the collision efficiency is calibrated using the settling column tests conducted by Enthoven (2021). The results of calibration show a good fit to the experimental data. Another advantage is that numerical simulations can provide the particle size distribution over time, which is not measured in the experiments.
The major novelty of this study is the coupling of the drift-flux model and the population balance equations, which inherits both the characteristics of population balance and the merits of drift-flux model in reducing computational costs. The flocculation modeling technique as proposed in this study can be incorporated as a module into an extended drift-flux model to predict the dispersion of deep-sea mining plumes.","Cohesive Sediment; Flocculation; CFD; OpenFOAM; Drift-flux model; Population Balance; Settling; Deep-sea mining","en","master thesis","","","","","","","","2023-10-01","","","","Offshore and Dredging Engineering","",""
"uuid:b8b918e8-9aa9-4eb8-a911-35662ad5fdb5","http://resolver.tudelft.nl/uuid:b8b918e8-9aa9-4eb8-a911-35662ad5fdb5","Pop your Bubble: A Lesson Plan for Teenagers to Rethink their online Filter Bubbles","Huang, Xiao-Mei (TU Delft Industrial Design Engineering)","van Boeijen, A.G.C. (mentor); Keller, A.I. (graduation committee); Delft University of Technology (degree granting institution)","2021","This graduation thesis report describes the research activities investigating the education on filter bubbles in Dutch secondary schools towards teenagers between 14-16 years old, and the design to improve this through including critical thinking techniques.
During this research the context and two main target groups were explored through literature research, observations, generative sessions and interviews. Insights from this research led to the design brief containing the design goal, interaction vision, design criteria, and learning objectives.
The design brief was formulated after exploring the context, media literacy, and stakeholders and target group. From this research, it was found that Dutch secondary schools are still at the beginning stages of implementing media literacy in itself in their curriculums, which means that filter bubbles are even less discussed in schools. Teenagers are confident about their media literacy and often confuse this with tech-savviness. This results in that they often think they learn more through Social Media. But even though teenagers nowadays in 2021 are raised alongside Social Media, teenagers are not necessarily media literate. Especially when it comes to critical thinking about the media consumed. To stimulate critical thinking in education, pupils have to be encouraged to come up with their own ideas and opinions and be able to discuss the different ideas with other people. Pupils also have to be able to connect subjects to their daily lives. For this to happen, a safe space needs to be created for pupils to be able to share perspectives with each other.
Following these insights, the design goal was to design an intervention that can be used as an addition to the “social studies” course in secondary schools in The Netherlands. This intervention should teach teenagers to critically think about the content they consume within their filter bubbles, through meaningful conversations with other teenagers about the content.
Ideation involved creative sessions and individual brainstorming and soon went into testing and iterating concepts. The final concept was evaluated with Social Studies teachers and teenagers. In conclusion, the Pop your Bubble: Lesson plan has created an opportunity in class for pupils to explore their own filter bubbles and discuss them with each other. Though further testing in context and research on the long-term effects of this lesson plan is required, teachers and participants agreed that this is a useful way to teach pupils that filter bubbles can have an influence on opinions and that it helps teenagers discuss them.","Social Media; Education; filter bubble; Teenagers; Dutch education; Critical Thinking","en","master thesis","","","","","","","","","","","","Design for Interaction","","52.0021456446433, 4.369971709304539"
"uuid:8f40561a-80be-4047-9760-63ab27207ffc","http://resolver.tudelft.nl/uuid:8f40561a-80be-4047-9760-63ab27207ffc","Reduce model unfairness with maximal-correlation-based fairness optimization","Huang, Wenxuan (TU Delft Electrical Engineering, Mathematics and Computer Science)","Loog, M. (mentor); van Gemert, J.C. (graduation committee); Lofi, C. (graduation committee); Delft University of Technology (degree granting institution)","2022","Supervised machine learning is a growing assistive framework for professional decision-making. Yet bias that causes unfair discrimination has already been presented in the datasets. This research proposes a method to reduce model unfairness during the machine learning training process without altering the sample value or the prediction value. Using an objective function that identifies the biased feature with maximal correlation estimation, the method selects samples to train the updated classifier model. The quality of the sample selection determines the extent of unfairness reduction. With an adequate sample size, we demonstrate that the method is valid in reducing model unfairness without severely sacrificing classification accuracy. We tested our method on multiple benchmark datasets with demographic parity and feature independence as the notions for a statistically fair classification model.","Machine Learning; Fairness Optimization; Maximal Correlation; Demographic Parity","en","master thesis","","","","","","","","","","","","Computer Science","",""
"uuid:e736cf29-f463-4b1f-9e18-aa7532dc1209","http://resolver.tudelft.nl/uuid:e736cf29-f463-4b1f-9e18-aa7532dc1209","Physics-Informed Neural Networks for Fluid Mechanics","Huang, Dobbin (TU Delft Aerospace Engineering)","Doan, N.A.K. (mentor); Delft University of Technology (degree granting institution)","2022","Physics-informed machine learning is a novel approach to solving flow problems with physics-informed neural networks (PINNs), that combines physical knowledge and machine learning.
This study aims to investigate the potential of the application of PINNs in fluid mechanics problems by solving two practical flow problems.
The first case considers the reconstruction of the full, time accurate flow fields with PINNs from partial data in the wake of an airfoil with periodic vortex shedding.
The results have shown a decent success in flow reconstruction case, but has trouble maintaining a high accuracy at higher time values.
This is likely due to the lack of a mechanism forcing a time marching approach to prevent information flowing in the opposite direction of the positive time axis.
The second case attempts to train PINNs on a steady flow problems with parametric NACA airfoils first to devise a strategy for training PINNs on a parameteric airfoil and show its feasibility.
This is followed by using the found strategy to train PINNs for the more complex flow cases with PARSEC airfoils to use them as fast surrogate flow solvers, while still producing the full flow fields with a comparable accuracy to conventional CFD.
Overall, the flow fields inferred by the PINNs have shown a good qualitative match with the OpenFOAM validation data, even in the most complex case with a PARSEC airfoil, which makes them sufficiently accurate as a surrogate flow solver for a preliminary design optimization.
These results show not only the technical feasibility of PINNs for fluid mechanics, but also a practical value with accelerating the computation time up to a factor of 3.7 when accounting for the training time and producing the OpenFOAM training data.","PINNs; Airfoil optimisation","en","master thesis","","","","","","","","","","","","Aerospace Engineering","",""
"uuid:01f5e0c7-e649-44c9-a160-e8a3e5f08db0","http://resolver.tudelft.nl/uuid:01f5e0c7-e649-44c9-a160-e8a3e5f08db0","PLASTICITY: Shaping the transitions to a resilient and circular plastic manufacturing system","Huang, Chloe (TU Delft Architecture and the Built Environment); Koch, Matthijs (TU Delft Architecture and the Built Environment); YU, Zhuo (TU Delft Architecture and the Built Environment); van Hal, Sophie (TU Delft Architecture and the Built Environment)","Sepulveda Carmona, D.A. (mentor); van der Veen, R.J. (mentor); Van den Berghe, K.B.J. (mentor); Dabrowski, M.M. (mentor); Rocco, Roberto (mentor); Delft University of Technology (degree granting institution)","2022","Different government bodies, from the European Union down to the Port of Rotterdam Authority have implemented the policy goal to become circular by 2050 to minimize demand and dependence on finite resources. However, a circular economy - an economic model in which materials circulate in closed loops and waste is viewed as a resource - is vastly different from the current linear system of extraction, consumption and waste. The plastics industry that is currently present in the port of Rotterdam is one such industry where large amounts of raw material is being used and large amounts of waste generated. It is still far from circular. Thus, transitions in the industry itself and in our interaction with products are necessary. The question that arises is: how can the transition to circular plastic manufacturing in the Rotterdam maritime region contribute to a more sustainable, resilient and just economy?
Theory on transition management and socio-technical systems, analyses of spatial use and networks of the plastics industry in South Holland, and research on the developments in plastic manufacturing, has led to the understanding of the current networks and flows in the plastics industry. A subsequent analysis of stakeholders, policies and design options has led to a vision and strategy for the South Holland region, on how to shape a new circular plastics economy.
In the proposed strategy of Plasticity, (1) the strength of a strategic location in the port of Rotterdam is used to expand the renewable cycle of the bioplastics industry, and (2) by actively engaging citizens in reusing and recycling plastic products on a local level in the whole region, a technical circular cycle is enhanced in the whole province. Plastic is used as an example to demonstrate the contemporary issues around dependency on fossil material in the South Holland context, but similar principles regarding integrating the biological and technical cycle, facilitating space for innovation and growth of circular models, and engaging the whole socio-technical system in the transition process can be applied to other sectors and places. This expands the applicability of this vision and strategy beyond plastic.
These people use crowdsourcing platforms to complete these microtasks.
Crowd workers have to work in front of a screen to complete these microtasks, risking musculoskeletal problems and other mental problems.
Their working conditions look similar to desk workers, who are people that work remotely or at the office behind a desk.
This study aims to find the health differences between crowd workers and desk workers.
It will provide a general overview on the subjective well-being, experienced and mental health.
In order to analyze the differences in health, a survey will be deployed on a crowdsourcing platform in order to recruit crowd workers and desk workers will be recruited through snowball sampling.
The questions of the survey are divided into 5 groups, each representing a health category: general health, workspace quality, physical well-being, social well-being and emotional well-being.
For this study 17 crowd workers were recruited and 9 desk workers.
From the results, desk workers are healthier in general, have a healthier workspace because some desk workers work in ergonomically good offices, a healthier physical well-being, a healthier social well-being due to them having colleagues and a better emotional well-being. Crowd workers have a lower level of stress, because of the microtasks being mostly very simple, while desk workers have mentally demanding deadlines and projects to work on.","Crowdsourcing; Health","en","bachelor thesis","","","","","","","","","","","","Computer Science and Engineering","CSE3000 Research Project",""
"uuid:d752b4b9-0122-49db-89df-caf229407304","http://resolver.tudelft.nl/uuid:d752b4b9-0122-49db-89df-caf229407304","Implications on Learning Outcomes and Eye-strain of using Telepresence Robots as a new Distance Learning Medium","Huang, Stephen (TU Delft Electrical Engineering, Mathematics and Computer Science)","Limbu, B.H. (mentor); Specht, M.M. (mentor); Anand, A. (graduation committee); Delft University of Technology (degree granting institution)","2022","Distance learning brings all sorts of advantages. The ability to follow lectures at home can save people transportation costs and time. Teaching through videoconferencing software such as Zoom is one of the methods to learn remotely. To explore new and better teaching methods, the possibility of using a telepresence robot is investigated. To determine its worth, an experiment is done to compare the learning outcomes of telepresence robot lectures to Zoom lectures. Differences in risk of eye-strain is also compared, as most distance learning methods are digital. An increase in risk of eye-strain may negatively impact the choice of adopting the learning method. Due to the small sample size, non-parametric tests were conducted. Concluding from the research, neither Zoom nor telepresence robot lectures had better learning outcomes compared to the other. The learning outcomes of both lectures were similar. Risks of eye-strain also did not differ between the two. Further analysis was done comparing the telepresence robot lecture with a hologram and a virtual reality lecture, as these were also part of the experiment. Similarly to zoom, there was no significant evidence that telepresence robot lectures had different learning outcomes or risks of eye-strain than holograms and virtual reality lectures.","Distance learning; Hybrid learning; Holograms; Telepresence robot; Learning outcomes; Eye-strain","en","bachelor thesis","","","","","","","","","","","","Computer Science and Engineering","CSE3000 Research Project",""
"uuid:8ea8a403-6b81-43f0-b7c8-9fd0a5c57f48","http://resolver.tudelft.nl/uuid:8ea8a403-6b81-43f0-b7c8-9fd0a5c57f48","Mapping User Intents in Web Search Queries to Types of Commonsense Knowledge","Huang, Xiaoao (TU Delft Electrical Engineering, Mathematics and Computer Science)","He, G. (mentor); Gadiraju, Ujwal (mentor); Cruz, Luis (graduation committee); Delft University of Technology (degree granting institution)","2022","Commonsense knowledge is a type of knowledge consisting of facts that humans use every day. Humans make queries in search engines with different user intents, and some of them can be answered by knowledge tuples. Different types of knowledge are stored differently in the knowledge bases. Being aware of the types of commonsense knowledge required to answer the queries can accelerate the process of finding corresponding knowledge for the search engines to give a response to users. For some queries with specific user intents, it is not possible to be answered solely with commonsense knowledge because some analysis and judgment from humans are needed. On the other hand, some queries can be answered with commonsense knowledge tuples and the user intents can have a strong indication of what the knowledge type is required to answer. The research is to look into how to map queries and their user intents to knowledge types and explore the impacts of user intents in the knowledge type classification. There was no existing dataset that had annotations on both user intents and knowledge types. In this work, the described dataset was created. Observations of the created dataset and experiments on three classifiers with accuracy being around 0.99 were conducted. The results show that user intents generally help the classification of the type of commonsense knowledge.","Commonsense Knowledge; User Intent; Web Query","en","bachelor thesis","","","","","","","","","","","","Computer Science and Engineering","CSE3000 Research Project",""
"uuid:7687d42f-fc7f-4dbb-931f-f8a19b91d6d6","http://resolver.tudelft.nl/uuid:7687d42f-fc7f-4dbb-931f-f8a19b91d6d6","The Place to Celebrate Individuality: A study of personalization in secondary territory space in elderly residence","Huang, Baoky King Yang (TU Delft Architecture and the Built Environment)","Jurgenhake, B.M. (mentor); van Deudekom, A.B.J. (mentor); van Andel, F.M. (graduation committee); Delft University of Technology (degree granting institution)","2022","","Secondary Territory; Personalization; Self Actualization; Elderly Residence; Individuality","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences","This is me",""
"uuid:80a5ffcd-a32a-4a0f-bbae-b91659f168d6","http://resolver.tudelft.nl/uuid:80a5ffcd-a32a-4a0f-bbae-b91659f168d6","Enhancing Wake Mixing in Wind Farms by Multi-Sine Signals in the Helix Approach","Huang, Louis (TU Delft Electrical Engineering, Mathematics and Computer Science)","van Wingerden, J.W. (mentor); Mulders, S.P. (mentor); Bierbooms, W.A.A.M. (graduation committee); Viré, A.C. (graduation committee); Taschner, E. (graduation committee); Delft University of Technology (degree granting institution)","2022","The development of offshore wind technology has progressed rapidly since the first offshore wind farm came to birth in 1991. During the last three decades, offshore wind has become an economically attractive option of renewable energy source for many countries to fulfill their commitment to combat the climate crisis. However, an open challenge remains in offshore wind, namely the aerodynamic interactions between multiple turbines, referred to as wake effects. When the upstream turbines extract energy from wind, they generate the wake with low velocity and high turbulence level on the downstream turbines, which substantially reduces the overall wind farm performance. The annual power production loss due to wake effects is generally 10 - 40%, which limits the reduction of the levelized cost of electricity for offshore wind energy.
Therefore, developing effective wind farm control strategies which could mitigate the wake effect has become an emerging research area in the past decade. Recently, a novel wind farm control strategy called the Helix approach is proposed. The Helix approach adopts the individual pitch control technique to dynamically deform the wake into the helical shape, which induces wake instability and thereby stimulates wake recovery. This control strategy has demonstrated promising potential to mitigate the wake effect and to enhance the wind farm performance. To date, the Helix approach employs single harmonic pitch signals. However, more complex and higher-harmonic signals to potentially improve the effectiveness of the Helix approach have never been explored. Therefore, the purpose of this master thesis is to explore the potential of using multi-sine pitch profiles to further enhance the wake mixing.
The high-fidelity aeroelastic simulator OpenFAST with its recent free vortex wake code is adopted to simulate the dynamic wake evolution. A Fourrier stability analysis is used to quantitatively identify the wake breakdown position. According to the simulation results for the multi-sine pitch profiles, the wake breaks down at 1.75 D, which is earlier than the one at 2.50 D for the original single-sine Helix strategy. The earlier wake breakdown indicates the potential of faster wake recovery, which is required to be validated by the higher-fidelity model in the future studies.","wind farm control; wake effects; wind energy","en","master thesis","","","","","","","","","","","","Mechanical Engineering | Systems and Control","",""
"uuid:542b0cfe-a730-4710-8972-ed8f18a2864f","http://resolver.tudelft.nl/uuid:542b0cfe-a730-4710-8972-ed8f18a2864f","City Loneliness: A healing practice in Amsterdam","Huang, Yu-Ching (TU Delft Architecture and the Built Environment)","Cavallo, R. (mentor); Medici, P. (mentor); Harteveld, M.G.A.D. (mentor); Delft University of Technology (degree granting institution)","2022","As cities densify around the world, the quality of city spaces increasingly shows its importance, influencing citizens’ mental health. Loneliness has become a normal phenomenon in the city along with its development and can affect every person for different reasons and cause serious problems. This research targets Amsterdam and argues why a well-being city such as Amsterdam also suffers from loneliness, aiming to explore the relationship between loneliness and architecture and find architectural solutions to reduce loneliness in Amsterdam. The existing research has shown that belongingness can act as a way to reduce loneliness. Thus, the main research question is:
How can architecture create a belongingness environment to alleviate and heal the feeling of loneliness in Amsterdam?
This research focuses on the theory of human relationship belonging, the place belonging, and the construction of belonging, searching for architectural strategies that can alleviate loneliness. Further analysis of Amsterdam and Amsterdam southeast’s city space answers the question and raises the opportunities to improve and solve the problems. Creating a belongingness environment with architectural strategies, based on the research, in city public venues provides a way to heal this unpleasant loneliness in Amsterdam and leads to a better well- being future.","Loneliness; Belongingness; Amsterdam; Architecture","en","master thesis","","","","","","","","","","","","Architecture, Urbanism and Building Sciences","",""
"uuid:ab7a9147-2e58-460d-b5b3-d8741db52223","http://resolver.tudelft.nl/uuid:ab7a9147-2e58-460d-b5b3-d8741db52223","Numerical investigation of bubble entrapment with tip vortex via an Eulerian-Lagrangian approach: Bubble motion near a tip vortex","Huang, Tzu-Yao (TU Delft Mechanical, Maritime and Materials Engineering)","van Terwisga, T.J.C. (mentor); Lidtke, A. K. (mentor); Stigter, Marinus (mentor); van Rijsbergen, M. X. (mentor); Delft University of Technology (degree granting institution)","2022","Tip vortex cavitation around the marine propeller is the primary source of the underwater noises emitted by ships. Investigating the tip vortex inception is important to understand the aforementioned side effect. The water quality, highly related to the bubbles population, surrounding the tip vortex is crucial to the tip vortex cavitation inception. This research explores how bubble moves around the tip vortex and investigates its background mechanisms. A one-way coupled Lagrangian bubble tracking model is applied to the Lamb-Oseen vortex and the hydrofoil tip vortex flow field, where the tip vortex is simulated with an open-usage CFD software, ReFRESCO. A series of capture time models have been developed by exploiting the bubble force (acceleration) balance in the Lamb-Oseen vortex to identify the crucial parameters. The other aspect of the acceleration analysis reflects the role of the lift force as the system's stabilizer, which has long been ignored. In the CFD tip vortex flow simulation, the bubble population evolution is investigated from upstream to downstream. Several kinds of bubble behaviors around the tip vortex flow have been identified via the numerical simulation, and simplified models based on the bubble force analysis have been proposed in order to explain them. Mainly due to the stagnation bubble events, clustering of large bubbles has been discovered a short distance downstream of the foil tip, implying that this may be a possible hotspot for tip vortex cavitation inception. The stagnation bubble phenomenon still needs to be further investigated, particularly in terms of quantifying its dependence on various flow parameters. The results also need to be rigorously validated which has not been possible as of yet due to insufficient measurement data. Still, this research manages to explore the bubble motion around the tip vortex and their fundamental mechanism.","tip vortex; cavitation inception; water quality; bubble entrapment; ReFRESCO; Eulerian-Lagrangian Method","en","master thesis","","","","","","","","","","","","Marine Technology | Ship Hydromechanics","",""
"uuid:3db7b87b-61eb-44f5-ab70-36a788455403","http://resolver.tudelft.nl/uuid:3db7b87b-61eb-44f5-ab70-36a788455403","Design and Benchmark of Front-end Voltage Control for Wireless Power Transfer","Huang, Zian (TU Delft Electrical Engineering, Mathematics and Computer Science)","Bauer, P. (mentor); Dong, J. (mentor); Yu, G. (graduation committee); Lekic, A. (graduation committee); Delft University of Technology (degree granting institution)","2022","In recent years, the Wireless Power Transfer (WPT) system has become more and more popular due to its prominent advantages, especially for Electrical Vehicle (EV) charging. The WPT systems are required to follow the EV battery charging profiles, thus more and more voltage control methods with distinctive characteristics are proposed and studied. The goal of this thesis report is to conduct a comprehensive benchmark of the front-end voltage control solutions.
This thesis report focuses on the front-end voltage control solutions including the front-end buck converter and the phase shift control based on the primary inverter. Six different front-end voltage control scenarios are designed and compared in terms of system efficiency. There are four scenarios of the front-end buck converters including the single-phase buck converter working in Continuous Conduction Mode (CCM), the single-phase buck converter working in Triangular Current Mode (TCM), the two-phase interleaved buck converter working in CCM and the two-phase interleaved buck converter working in TCM. There are also two scenarios of primary inverter-based phase shift controls including phase shift with and without phase delay. The single-phase buck converter working in TCM has the highest efficiency reaching 95.5% at a light load. The phase shift control scenario with phase delay has the highest efficiency exceeding 96.5% at a heavy load.
Different from previous research on phase shift control, this thesis report conducts an in-depth harmonic analysis and compares the accuracy of harmonics analysis with the accuracy of fundamental wave analysis. The conclusion not only proves that fundamental wave analysis is reliable and accurate enough to calculate the phase shift parameters for the S-S compensation but also improves the calculation accuracy at a light load by harmonics calibration.","Wireless Power Transfer; TCM Buck Converter; Phase Shift Inverter; harmonic analysis; Two-phase interleaved buck converter","en","master thesis","","","","","","","","","","","","","",""
"uuid:68df6c57-5d34-4329-899a-a2130fad5544","http://resolver.tudelft.nl/uuid:68df6c57-5d34-4329-899a-a2130fad5544","Image-matching based navigation system for robotic ureteroscopy in kidney exploration","Huang, ZhiLi (TU Delft Mechanical, Maritime and Materials Engineering)","Lai, C. (mentor); Dankelman, J. (mentor); Della Santina, C. (graduation committee); Delft University of Technology (degree granting institution)","2022","Kidney stone disease has become the most common disease of the urinary tract. Flexible ureteroscopy (fURS) is one of the methods to perform diagnosis or treatment for the stones inside the kidney. However, because of the complex structure inside the kidney with multiple calyxes and the limitation of the ureteroscope, surgeons find it difficult to know which calyx is being observed and where the ureteroscope tip actually reaches during the ureteroscopy procedure by only using the ureteroscope camera views. To solve this problem, this thesis proposed an image-matching-based navigation system for robotic ureteroscopy in kidney exploration. The system consists of two parts: pre-operation and post-operation. During pre-operation, the virtual ureteroscopy (VURS) environment is rendered from the 3D kidney model, which is generated from computed tomography (CT) scan data. The VURS images of calyxes inside the kidney are collected and then processed to perform edge feature extraction as the matching virtual image database (VID). In post-operation, real calyx images (RCIs) are collected. For each RCI, image processing is used, and its edge features are extracted as the matching input. By performing the matching algorithm between edge features of the RCI and the VID, the best matching result image in the VID can be found according to the RCI. Then the location of the ureteroscope can be shown in the virtual ureteroscopy environment. This thesis uses an open source kidney model to replace the data from CT scans due to resource limitations. Unity software is used to generate the VURS. The VID is collected manually. A robotic ureteroscope prototype and a 3D-printing kidney phantom based on the open source kidney model are used to simulate the fURS procedure to get RCIs. After applying image processing techniques to RCIs, the shape context (SC) matching method is used to find the best matching image from the VID. The results are validated by the EMT system. The whole system is validated through both simulation images and the experiment. The successful rate of matching the simulation images is 92%, while it reduces to 62.5% when matching the RCIs. This performance difference is caused by the poor image quality of RCIs, which can be improved by selecting a more suitable light source and a digital camera.","Ureteroscopy; Navigation systems; Image Matching; Virtual Endoscopy","en","master thesis","","","","","","","","","","","","Mechanical Engineering | BioMechanical Design","",""
"uuid:c2dd652a-13ec-418d-a25e-5a1d9478892f","http://resolver.tudelft.nl/uuid:c2dd652a-13ec-418d-a25e-5a1d9478892f","Exploring Intelligent Technology for Older People through Speculative Design","Huang, Yu (TU Delft Industrial Design Engineering)","Rozendaal, M.C. (mentor); Lupetti, M.L. (mentor); van Grunsven, J.B. (graduation committee); Delft University of Technology (degree granting institution)","2022","This report first discusses the phenomenon of aging, how it is commonly understood, and the state-of-the-art of the technology for aging people (gerontechnology) (chapter 1). In the analysis, the author briefly describes the origin and development of the notion of aging through medical, social, and cultural lenses. How the negative narrative around aging has hamstrung the innovation for older people is presented by enumerating three types of design pitfalls identified in today’s mainstream gerontechnology. Drawing on a body of literature (e.g. the ‘successful aging model’ and the ‘personhood turn’ in the ‘care model’) and projects, the author shows new voices attempting to overturn this negative narrative. The Capability Approach (CA), especially Nussbaum’s capability theory which provides a concrete and substantive normative foundation for probing into older people’s lives is introduced (chapter 3 prologue). Interviews are conducted to obtain in-depth understanding of people's needs, wants, and challenges (chapter 3). Based on the literature research and empirical studies, a gap between the real needs and wants emerging in the aging process and what is provided by current mainstream gerontechnology is identified (tension 1) (chapter 4).
Informed by several inspiring design frameworks or theories (e.g. design for appropriation, end-user development, ambiguity in design, meta-design), the author proposed design for openness as a potential design strategy to address the first tension (chapter 5 prologue). What is so powerful about ‘openness’ in design is its potential to satiate various needs over time, in the meanwhile, promote autonomy in users. A theoretical model is theorized to provide firm design handles (chapter 5 prologue). Next, co-speculation sessions are conducted to gather situated knowledge and to experiment with the idea of design for openness (chapter 5). Findings from the sessions reveal the potential risk of leaving the design completely open: ineffective appropriation caused by misalignment between use and design (chapter 5). How to lower the seemingly paradoxical misalignment between design and use while still maintain the openness in design becomes the focus of the rest this research (tension 2) (chapter 5).
A concept artifact is crafted as an explorative attempt to address the misalignment between use and design (chapter 6). Next, the evaluation of the concept artifact is conducted which results in rich design implications (chapter 7). Insights from the evaluation sessions also help further develop the theoretical model (chapter 8). An alternative design process that's different from the traditional one is put forward and limitations are discussed and directions for future research are sketched out (chapter 8). The report closes by reflecting on the whole project and summarizing the main contributions of this project (chapter 9).
Based on the current research gaps, this study develops topology-based PTN hierarchy quantification and comparison methodologies. First, six topological characteristics of PTN hierarchy are identified from the element scale (vertex accessibility, element intermediacy and vertex cluster importance) and network scales (scale-free structures, high-clustering structures and vertex connection pattern). Second, six element-based or network-based topological indicators are selected to quantify the topological characteristics. For element-based indicators (vertex degree centrality, closeness centrality, betweenness centrality and eigenvector centrality), the coefficient of determination (R square) of the indicator's probability density distribution fitting the skewed normal distribution represents the PTN hierarchy. For network-based indicators (modularity coefficient and assortativity coefficient), the quantified indicator values represent the PTN hierarchy. Next, the radar chart is developed for comprehensively assessing the normalised six-dimension PTN hierarchy.
To evaluate the performance of the methodology, a database based on the GTFS data containing topological information of 63 high-capacity unimodal PTNs worldwide is applied with the hierarchy quantification methodology as a case study. In the PTN hierarchy comparison, the hierarchy in the closeness centrality and betweenness centrality are prone to be high and have higher importance for PTN operation, reflecting the hierarchical organisations of stops' accessibility and the traffic intermediacy on infrastructures. PTN hierarchy in the eigenvector centrality and network modularity dimensions reflect the mono-centric or multi-centric network structures. In the vertex degree centrality and network assortativity dimensions, the identified PTN hierarchy topological characteristics are less significant. In mode-wise effects analysis, the order of modes having PTN hierarchy from high to low is metro, tram and BRT networks. The continent-wise effects show that the European PTNs usually have a higher hierarchy than North American PTNs.
Overall, the research offers a unified topology-based PTN hierarchy as a network property. This study's quantification and comparison methodologies bring a comprehensive multi-dimension and intuitive perspective for PTN hierarchy with the radar chart representation. With the case study, the six-dimension PTN hierarchy, the mode-wise and continent-wise effects are analysed. The methodology benefits the universal PTN performance comparison with basic topological information.","hierarchy; public transport networks; network topology; multi-dimensional quantification; GTFS data; closeness centrality; betweenness centrality; unimodal PTN; high-capacity PTN; comparison","en","master thesis","","","","","","","","","","","","Civil Engineering | Transport and Planning","",""
"uuid:f52643f9-defa-4d74-9850-2d6ad25e874c","http://resolver.tudelft.nl/uuid:f52643f9-defa-4d74-9850-2d6ad25e874c","Adaptive regeneration of urban village: in Shenzhen in the context of rapid urbanization","Huang, Chloe (TU Delft Architecture and the Built Environment)","Qu, L. (mentor); Hausleitner, B. (graduation committee); Delft University of Technology (degree granting institution)","2023","Urban regeneration and urbanization are always concomitant topics and phenomena that appear in the history of China and other countries. Until the end of 2021, China's urbanization rate has reached 64.72%. Cities of different sizes and levels have been, are, or will soon be entering the era of inventory planning. Urban villages are the author's primary focus topic of urban regeneration under rapid urbanization. On the one hand, urban villages are the product of rapid urbanization.On the other hand, urban villages are also the key potential areas for urban regeneration. Urban villages have their inevitable ""dynamic"" and ""transitional"" nature in the process of urbanization. They are the link between urban and rural areas and the ""first stage for living"" for different groups.","Adaptive regeneration; rapid urbanization; Socio-Spatial Segregation; Resilience; uneven development; Shenzhen","en","student report","","","","","","","","","","","","Architecture, Urbanism and Building Sciences | Urbanism","",""
"uuid:91dba535-34d6-4c48-9529-670024713933","http://resolver.tudelft.nl/uuid:91dba535-34d6-4c48-9529-670024713933","Total Harmonics Distortion (THD) Reduction Techniques in Class D Amplifiers","Huang, Shijie (TU Delft Electrical Engineering, Mathematics and Computer Science)","Verhoeven, C.J.M. (mentor); Montagne, A.J.M. (mentor); Serdijn, W.A. (graduation committee); Stelwagen, Frank (graduation committee); Visee, Richard (graduation committee); Delft University of Technology (degree granting institution)","2023","Class D amplifiers find widespread application in audio devices for driving load speakers, primarily due to their remarkable efficiency. Nonetheless, this enhanced efficiency often comes at the expense of reduced linearity. Hence, techniques for reducing Total Harmonic Distortion (THD) are important in the context of class D amplifiers.
The analysis of the distortion mechanisms is first presented. Specifically, emphasis is placed on the distortion generated within the power stage, encompassing aspects such as deadtime distortion and rising and falling time distortion. Both of them are found to be related to the input signal. Subsequently, the compensation technique is applied to the conventional class D amplifier to reproduce and cancel the error. The idea of the compensation approach involves modifying the amplitude of the triangular waveform based on the input signal. A 12 dB THD improvement is achieved in the concept verification section, which is conducted in LTspice.
The negative feedback serves as another technique to achieve THD reduction. A straightforward two-step design methodology is presented to avoid design iterations in the concept design phase. The phantom zero technique is applied when doing the frequency compensation of the feedback loop. The validation of the concept is performed through the use of SLICAP, while the circuit implementation and simulations are carried out within Cadence. Remarkably, this technique results in an impressive -111.8 dB THD reduction, achieved when the output power equals 1 W.","Class-D amplifiers; THD reduction; Compensation; Feedback","en","master thesis","","","","","","","","","","","","Electrical Engineering","",""
"uuid:b009e5b3-03a8-4b2f-b89b-d8471fbdc30c","http://resolver.tudelft.nl/uuid:b009e5b3-03a8-4b2f-b89b-d8471fbdc30c","Securing an Efficient Lightweight AES Accelerator","Huang, Ruoyu (TU Delft Electrical Engineering, Mathematics and Computer Science)","Gaydadjiev, G. (mentor); Taouil, M. (mentor); Ma, Kezheng (mentor); Venkatesha Prasad, Ranga Rao (graduation committee); Delft University of Technology (degree granting institution)","2023","Internet of Things (IoT) devices regularly process sensitive data, including personal information. Therefore, ensuring their security is crucial to avoid damage and prevent data breaches. The Advanced Encryption Standard (AES) is generally regarded as one of the most popular cryptographic algorithms for ensuring data security. Typical lightweight implementations of the algorithm published in the literature focus on area and power optimization, while neglecting the performance. This paper presents a novel lightweight approach for the AES algorithm and considers both encryption and decryption. In terms of performance per unit area and performance per unit power, our 32-bit design outperforms the state-of-the-art by 1.69x and 1.27x, respectively. These improvements become even larger when implementing higher data-path designs, such as 64-bit or 128-bit designs. Our non-DOM AES design is secure against Correlation Power Analysis (CPA) but vulnerable to Template Based Attack (TBA) when more than 1500 traces are considered. To enhance its resilience against side channel attacks (SCAs), we modified our design by adopting and further improving on the most recent countermeasure, i.e., Domain-Oriented Masking (DOM). The results demonstrate that incorporating DOM into our design enables it to withstand against both CPA and TBA. Besides, our simplified eight-stage and five-stage 1st-order DOM SBOX designs achieve a reduction in area of 9.9% and 6.9% compared to the original proposed designs, respectively.","Advanced Encryption Standard; Domain Oriented Masking; Lightweight Accelerator; Internet of Things; Side Channel Attacks","en","master thesis","","","","","","","","2023-12-31","","","","Computer Engineering","",""
"uuid:009d5078-d129-4037-a3d7-85ab4e5c435e","http://resolver.tudelft.nl/uuid:009d5078-d129-4037-a3d7-85ab4e5c435e","Building a Sustainable Future of Education: An Investigation into the Sustainability of Digital Education Technologies in European Higher Education Institutions","Huang, Morris (TU Delft Technology, Policy and Management)","Okur, Ö. (mentor); van der Voort, H.G. (graduation committee); Huang, Yilin (graduation committee); Delft University of Technology (degree granting institution)","2023","The digitalization of European universities’ tool infrastructure has transformed how institutions operate and deliver education to students, from sharing content on learning management systems to hosting lectures on video-conferencing platforms. However, despite many new benefits of digital education technologies (DETs) and their contribution to reaching the United Nations Sustainable Development Goal 4 targets for Quality Education, it also comes with new challenges like user privacy, environmental impacts, and shifting power dynamics between institutions and service providers. Additionally, concerns have been raised regarding the responsible development and longevity of the university’s digital infrastructure given the recent rapid digitalization trend and how new DETs are selected.
Sustainability assessment can be a useful model to evaluate an institution’s DET selection process as it provides a holistic evaluation through a multidimensional perspective to develop a more responsible and future-proof approach to digital education infrastructure. However, a multidimensional sustainability analysis has not been applied in the context of DET selection. Therefore, it is unclear to decision-makers what sustainable DET looks like and what role sustainability plays in the DET selection process. This study addressed this gap by answering the following question: How are European higher education institutions incorporating sustainability into selecting digital education technologies?
The sustainability dimensions of DETs were formulated by conducting a literature review of contemporary models, encompassing the environmental, social, and technological aspects. A more sustainable DET increases the positive impact along each of these dimensions. An environmentally sustain- able DET preserves and protects natural resources by reducing the environmental impact through its hardware and software. A socially sustainable DET increases equal access to education for all learners, regardless of socioeconomic status, disabilities, or geographic location while preserving individual privacy. A technologically sustainable DET is long-lasting, possesses the necessary functionalities, and balances a tool’s simplicity, openness, and ownership. While most sustainability models include the economic dimension, due to the university’s non-profit nature and the common prioritization of economic factors above other criteria in decision-making, this study excluded the economic dimension to examine the other dimensions more closely. Furthermore, the pedagogical dimension was omitted due to its sustainability considerations typically arising after the implementation of a DET, rather than during its selection stage and therefore is beyond the scope of this research.
Four key actors involved in the DET selection process were identified through an actor analysis. These include the university’s Head of IT who oversees the institution’s infrastructure system and their IT tool specialists who provide technical expertise, service providers whose products comprise the DET market, and education associations who help universities procure DETs. Ten semi-structured interviews were conducted with European university Heads of IT to gather data on the current DET selection process and the challenges institutions face when incorporating sustainability into DET selection.
The sustainability dimensions were used in conjunction with grounded theory open and axial coding analysis to evaluate the sustainability of current DET selection processes. The results showed that decision-makers predominantly utilize the EU-regulated tendering process to select DETs, which comprises minimal sustainability criteria while assigning significant importance to the economic factor (i.e., DET price). Additionally, interviewees shared they prioritize social and technological sustainability, specifically the privacy, data security, and functionality of DETs over other sustainability criteria. On the other hand, environmental sustainability is underrepresented in DET selection criteria. This is primarily due to the lack of available data and initiatives collecting DET environmental impact metrics, making it difficult for decision-makers to create relevant requirements and kickout criteria to compare DET options based on environmental sustainability. Finally, the analysis illustrated the three most common challenges that hinder sustainable DET selection are the limited financial and human resources, the insignificant or lack of sustainability criterion weighting, and the long and inflexible tender process.
Overall, this study contributes to filling the knowledge gap in understanding the sustainability of current European universities’ DET selection process and highlights key challenges decision-makers and researchers should focus on to improve the sustainability of digital education technologies. Future research can build on this work by expanding the scope beyond Northwestern European institutions, interviewing other decision-maker actors, and developing a standardized selection process for sustainable DET selection.
Additionally, recommendations were made to the four actor groups as well as general advice for universities to increase DET sustainability. The Head of IT should prioritize the environmental aspect in DET criteria and collaborate with service providers to address environmental impact metrics. They should also encourage the development of new tools by teachers and students. The IT tool specialist should engage in co-development with service providers for better tool support and to ensure a secure and functional digital infrastructure. Service providers need to align their products with sustainability criteria, propose pilot projects to universities, and share environmental impact metrics with relevant stakeholders. Education associations should organize collective efforts to enhance the sustainability of the DET tendering process and offer streamlined services like joint procurement and model contracts to simplify the selection process. Universities could transition to renewable energy to reduce DET’s carbon footprint, implement e-waste recycling and disposal programs, and support research into sustainable DET.","Digital education; Sustainability","en","master thesis","","","","","","https://docs.google.com/spreadsheets/d/1K4XZEIYKSaIPBHQd7Cb-a6sEV8gq7yqTiyXoc1o3dNA/edit?usp=sharing Codebook","","","","","","Engineering and Policy Analysis","",""
"uuid:81e1c72d-fc90-42c2-8dd1-a8319d19b15f","http://resolver.tudelft.nl/uuid:81e1c72d-fc90-42c2-8dd1-a8319d19b15f","DOC and Ammonium Removal Processes in Slow Sand FIlters - Influence of Grain Size and Flow Rate","Huang, Yuwei (TU Delft Civil Engineering & Geosciences; TU Delft Water Management)","Trikannad, S.A. (mentor); van der Hoek, J.P. (graduation committee); van Halem, D. (graduation committee); de Kreuk, M.K. (graduation committee); Delft University of Technology (degree granting institution)","2023","Slow sand filters (SSFs) are essential for ensuring microbial quality and biological stability of drinking water in the Netherlands. However, gaps exist in understanding of removal processes of dissolved organic carbon (DOC) and ammonium and the effects of grain size, loading rate, and backwashing on removal in SSFs.
Four lab-scale SSF columns filled with fine (0.4-0.6 mm) and coarse (0.85-1.25 mm) sand were constructed and operated in two phases with a total of 165 days. In phase I, SSFs operated at a flow rate of 0.5 m/h to investigate the influence of grain size. After stabilization, higher loading rate of 2 m/h and backwashing procedure (20% expansion for 5 min) was applied during the phase II experiment. Various physicochemical and biological parameters, including DOC, ammnoium, phosphate, and ATP were analyzed in water along the filter depth. Additionally, biomass development on sand was quantified suing ATP measurement.
Results showed the stable SSF operation after 90-100 days, removing 100% of dosed 1.5 mg/L of DOC and 1.0 mg/L of ammonium. Compared with fine sand, coarse sand had similar removal performance but better backwashing effectiveness and lower clogging risk. Increased loading rate led to faster microbial growth, reducing operational lifespan, and poor removal performance. Backwashing showed minimal impact on DOC and ammonium removal capacity and microbial activity, which were recovered after backwashing within 7-14 days, indicating the potential for backwashing to prolong SSF’s operational lifespan.
This research investigated the DOC and ammnoium removal processes and the influence of grain size, loading rate, and backwashing on filter performance. Providing insights for optimized SSF design and operation. Future studies could delve into mechanisms using isotope analysis or metagenomics, along with more comprehensive sand sample analysis.
This study focused on optimizing BPMED for the recovery of ammonia and citric acid from ammonium citrate scrubber effluents. The impact of current density, membrane configuration, feed solution characteristics (pH and initial N concentration), and temperature on recovery efficiency, current efficiency, and energy consumption of a BPMED system was evaluated. The limiting current density (LCD), a key factor in the normal operating range of the system, was determined using the Cowan and Brown method, yielding a critical value of 1.01 A/m2.
Comparative experiments conducted on three BPMED configurations, including 3-chamber BPMED (BPCA), 2-chamber base BPMED (BPC), and 2-chamber acid BPMED (BPA), revealed the superior performance of the BPC in terms of current efficiency, energy consumption, and running time. The optimal operating time of BPC was determined to be 120 minutes, achieving a recovery efficiency of 55.9%, a current efficiency of 44.2%, and an energy consumption of 8.4 kWh/kg-N.
Moreover, regression models were established using Box-Behnken design (BBD) from response surface methodology (RSM) to optimize operating conditions (pH, initial N concentration, and temperature), maximize recovery efficiency, current efficiency, and minimize energy consumption. Verified by analysis of variance, normal probability plot, and residual analysis, the model showed high accuracy and significance.
Univariate analysis elucidated that pH and initial N concentration were found to be important variables, while temperature was not. Increasing pH (3–7) enhanced recovery and current efficiency while decreasing energy consumption. Higher initial N concentrations (2–10 g/L) improved current efficiency, decreased energy consumption, but reduced recovery efficiency, emphasizing the need for a careful balance. Temperature variations (20–40°C) had no significant impact on BPMED. Critical factors limiting ammonia recovery efficiency, current efficiency, and energy consumption were identified, including solution conductivity, H+ ion leakage, water migration, and NH3 diffusion.
Furthermore, the study revealed non-significant interactions between these variables through 3D response surface plots and 2D contour plots. Adjusting operational variables proved feasible for optimizing performance indicators. The optimized conditions (pH 6.05, initial N concentration 6.67 g/L, temperature 30°C) were experimentally verified, and the predicted values were in good agreement with the actual values, confirming the reliability of the optimization model. Specifically, the recovery efficiency was 52.9%, the current efficiency was 45.4%, and the energy consumption was 7.0 kWh/kg-N.
Energy evaluation of the BPMED system in BPC configuration under optimal conditions showed significant energy efficiency. Based on the comparison with the available literature, the integration of BPMED with air stripping and organic acid scrubbing could improve energy efficiencies and lower chemical consumption while offering a closed-loop system.
Future research should explore principles to inhibit ion leakage and water migration, analyze the combined effects of various operating variables using RSM, and validate the potential for lower energy consumption in full-scale BPMED. Developing continuous BPMED processes is crucial for full-scale application, and integrating BPMED with other processes such as air stripping and acid scrubbing may enhance ammonia recovery and production efficiency.
The insights gleaned from this study provided a solid foundation for enhancing ammonia recovery processes from ammonium citrate scrubber wastewater, thereby promoting sustainable and resource-saving industrial practices.