The present study was designed to gain a deeper understanding of RTI control and Supply Chain Coordination, with a specific focus on the practical challenges experienced in the reverse logistics by asset-owner and asset-users. A case study at EPS - an RTI owner - is performed and a practical problem has been addressed with a design science and TIL systems engineering approach. It was observed that a huge amount of deposit is allocated to a retailer's generic account. The current state analysis found that this problem is mainly due to inefficiency in the current identification process with physical SSCC labels. The design goal of minimising the "Delta" -the number of unidentifiable return packages- was defined. Ways to redesign the reverse logistics were determined with the aim that all return packages can be allocated to the retailer at shop level. Based on the future state requirements and the design goal, the concept of matchmaking is developed as a way to achieve the design goal. This thesis shows that a matchmaking system can improve the traceability of return packages and that it has the potential in bringing the Delta of return packages with missing shoplink to zero. The matchmaking system is defined as the framework that ensures matchmaking, which uses a "key" generated by the sender to represent the return package. If the receiver can find the key upon arrival of the return package at the depot, the sender can be identified. Seven matchmaking systems were considered. Five alternatives use unique tray identities as key. One alternative uses the load carrier as key and the last alternative uses the return package identity as key. The validation results show that an "all read" or "reading of all individual trays" is not a requisite for a working matchmaking system. By contrast, as long as a certain ratio of reading at two locations is reached, an all-read scenario can be mimicked. The assessment investigated the instances in which zero mismatch take place. Results show that the higher the data capture capability of both the sender and receiver, the higher the chance a match can take place and the smaller the chance of a mismatch. This thesis creates insights on requirements for enhancing traceability of RTI's in the return chain and developed a matchmaking concept that can address the practical problem of returns without traceability of shop origin. The developed matchmaking concept is the outcome of an analysis of the current state and makes use of data elements that are already being collected in the database, in the case of EPS. The study addresses how collected data can be leveraged for enhanced RTI management in the reverse logistics and may inspire practitioners to face challenges with a similar lean approach.

This research investigates the application of a digital twin in managing challenges of variability and complexity within systems by using a case study at KLM Engineering & Maintenance. Using the DMADV (define, measure, analyse, design and verify) methodology, the research evaluates the problem using a literature review, measures and analyses the current state of the Logistic Handling Area (LHA), designs a digital twin concept and verifies its value. The literature review highlights the variability in the Maintenance, Repair and Overhaul (MRO) industry, which enables the investigation of digital twin applications for dynamic coordination. The analysis phase reveals significant operational challenges arising from variability in inflows and processing times, enhanced by system complexity and integral coordination issues between departments. To address these challenges, a digital twin is designed that enables real-time monitoring of KPIs, testing of dynamic resource allocation and integral operational target setting. The value assessment shows that the digital twin can support process operators by managing variability through continuous monitoring and evaluation of resource allocation, ultimately achieving predictable and stable system performance in a complex and variable environment.

This research aim was to design a centralised model that redefines definitions, standardises maintenance by categorisation, and reduces waste by introducing new slot lengths, leading to an equilibrium between flights and maintenance. This equilibrium enhances the airline’s capacity to manage maintenance efficiently and ensures greater uptime. The model addresses the important aspects of airline planning, including maintenance, flight and operation planning. Lean Six Sigma theories serve as a framework to combine the different plannings. The key importance is that the model considers all the stakeholders instead of only one so that the equilibrium between excessive flying and excessive maintenance can be established. In striking such a balance, uptime is assumed to increase.

This paper focuses on the effect of different storage policies on the performance of RoboticMobile Fulfilment Systems (RMFSs). The research is conducted under the instructions of the Technical University of Delft and CEVA Logistics the Hague. The aim of the research is to develop a decision support tool that can aid companies in the choice of the storage policy to use for their RMFS. RMFSs have multiple different levels of decision problems that need to be solved. The performance of a RMFS highly depends on the algorithms that are applied to solve these decision problems. This research focuses only on the storage policies of a RMFS. In this case storage policy refers to the decision in which pod items should be stored and where on the storage area the pod should be positioned. In order to gain a good understanding of the effect of such a policy on the overall performance of a RMFS, experiments should be performed. Physical experiments are however very hard and costly to perform. This research therefore makes use of a simulation study to test different storage policies in different scenarios. The simulation model used is an adaptation on an agent-based semi-open queuing network framework model by Merschformann et al. (2018a). In the experiments four different storage policies are investigated under three different storage layouts. The results of the simulations are analysed via the throughput, the pile-on and the distance travelled during the simulation. After this a score is given to both the picking as well as the replenishment side of the system. It is important to investigate both sides of the system since the flaws on one side can negatively affect the other side. The scores of the replenishment and picking processes are then averaged to gain a final score which indicates the overall performance of the policies. Finally a fifth policy has been developed where each pod can contain multiple different sized compartments. Unfortunately testing and verification of this policy was not possible in the given time frame. For this reason it has been left out of the experiments.

The exponential growth in maritime trade during the 21st century has posed notable challenges for container terminals, resulting in congestion and operational inefficiencies. This study delves into the efficacy of Amphibious Automated Guided Vehicles (AGVs) as an innovative remedy to tackle these issues and facilitate the shift towards autonomous operations at container terminals. Motivated by the need to optimize spatial utilization and reduce reliance on conventional material handling equipment in port areas, this study employs an agent-based modeling approach. Subse- quently, the formulated model is applied in a case study focusing on major Ports of the World. This study undertakes a critical examination of the potential of Amphibious AGVs in alleviating congestion and operational challenges faced by container terminals in the context of an increasingly interconnected global trade setting. By conducting a thorough examination of existing literature and creating a generalised simulation model, this study aims to offer valuable insights that can influence the evolution of container terminal operations.

It is becoming increasingly clear that the effects of climate change should be decreased or even mitigated. Green alternative sources of energy are being explored, and wind energy emerges as an important option that can be exploited on a large scale. Wind turbines are placed more and more often offshore due to larger and more stable wind resources. The most common foundations for these turbines are monopiles. The future outlook for these turbines and their foundations is that they will become bigger. An important design characteristic of monopiles is the natural frequency of the pile. In order to keep dynamic effects to a minimum, excitation frequencies should not coincide with the natural frequency. The primary source of excitation of monopiles are bending moments. Therefore, this thesis will take a closer look at the dynamic bending capability of monopiles. There is a lack of knowledge on dynamic effects of bending moments on steel cylindrical shells (monopiles). While the dynamic axial buckling capacity of cylindrical shells has been researched extensively, there is little known on the dynamic bending buckling capacity of such shells. This thesis investigates the influence of loading rate on the dynamic buckling capacity of monopiles subjected to bending moments. For this, a finite element model is constructed which is validated by analytical models. Later on, the finite element model is used to conduct a parametric study to investigate the effect of loading rate on buckling capacity. The scope of this study excludes factors such as soil dynamics, fluid structure interactions, residual stresses, and lateral forces. The focus is solely on the cylindrical shell of monopiles, excluding secondary steel from consideration. Initial geometric imperfections are considered as local perturbations necessary to initiate buckling, while other factors that may affect lateral forces or overall structural capacity are excluded. This study will show that different parameters play part in the dynamic bending buckling behavior of cylindrical shells. The natural frequency of the cylinder, as well as the non-dimensional length together with the yield stress of the material play an important role in the dynamic buckling capacity. This research concludes that cylindrical shells with higher natural periods are more influenced by dynamic bending moments than cylinders with shorter periods. Next, shorter, stocky cylinders exhibit higher dynamic buckling capacities than slender cylinders. Also, imperfections are found to decrease the buckling capacity of cylindrical shells, but this effect diminishes for increasing loading rates. Keywords: Offshore wind energy; Cylindrical shells; Dynamic buckling; Loading rate; Imperfections; FEM;

The European Union has recently revealed a plan called ”Fit for 55.” The plan aims to reduce carbon dioxide emissions by 55% before 2030. It includes FuelEU Maritime, which will introduce new emission regulations for ships over 5000 gross tonnages. The regulations will require shipowners to reduce their carbon footprint. The European Union has decided not to wait for the International Maritime Organisation’s emission rules (IMO) and will enforce them for ships by 2024. By 2025, the rules will extend to offshore vessels with a gross tonnage of 400 or more and general cargo vessels carrying commercial goods between 400 and 5000 gross tonnages. Efforts are being made to find a hydrogen carrier that closely resembles conventional oil-based products to comply with these regulations. All these fuels need to be produced with renewable energy sources, which have their efficiency losses. Renewable fuel production is only estimated to have a chemical efficiency of 50%. Innovation in the shipping sector is necessary to reduce energy losses. The shipping sector fits the rules of rural society, where incremental innovations are preferred over radical changes. However, radical change is necessary to accomplish the energy transition in shipping. According to the DOI theory, innovators are the first group of adopters. Innovators are eager to try new ideas and have a cosmopolitan (global) network. These innovators will play a critical role in the energy transition in the shipping sector. The study’s objective is to analyse if it is possible to influence a given adoption of the innovator. First, the research outlines the theoretical framework for the study. The literature search aims to determine a transition framework to answer the research sub-questions. The framework’s scope will be refined to the innovator group and the maritime sector. A case study will be conducted to test the defined framework, and factors outside the scope may be included if needed. The literature collection approach involves determining the philosophical framework before researching the sociological framework. The mainstream innovation and inclusive innovation frameworks have been identified from a philosophical perspective. The mainstream innovation framework focusing on radical and technological typology is more appropriate for the research study. Rogers’s sociological framework can be used to describe the adoption process. The Scopus search has been used to identify different theories, including spatial innovation frameworks, sectoral innovation systems (SIS), technological innovation systems (TIS), and path development. Finally, the study provides an overview of the innovation systems and their corresponding frameworks……

Semiconductor product development becomes increasingly challenging due to diminishing product life cycles, miniaturization, introduction of new physical principles, and new manufacturing processes. These problems are compounded in the absence of standardized development processes for the most complex semiconductor products like MEMS technologies, because the manufacturing of these products is often outsourced. Suppliers play a pivoting role in the realization of the product, from product design until process design and ramp-up. The supplier selection problem in this industry denotes the challenges in finding the right supplier while meeting all the technical, process and business requirements. The contribution of this research is in presenting how to develop a generic methodology for data-driven co-development. Thereby, this work presents a novel product development framework that leverages co-development and supply chain integration through data-driven decision-making. Co-development is reached through standardized methods for generating the required engineering output for supplier selection. Supply chain integration is introduced in the early stages of product development. This synthesizes with the outsourced manufacturing processes. Clustering algorithms are used to effectively shortlist suppliers based on their competences, and provide insights into supplier profiles and gaps. The latter is used to draw strategies for developing unattainable technologies. Using the framework, the required engineering output for supplier selection was generated in 77% less time while reducing information asymmetries between actors in the product development process. Furthermore, the framework made it possible to quantify decisions, allowed for supplier profile recognition and gap identification through its hybrid automated approach, and supplier shortlisting in 95% less time. This efficiency does not only showcase the immediate benefits of the proposed methodology, but also lays the foundation for future research towards a fully automated approach in semiconductor product development. The developed framework includes information flows between actors and steps in the product development process, their interfaces and demonstrates its added value and potential for a fully automated yet efficient future approach in semiconductor product development.

This study entails the development of a planning model utilizing Centralized Model Predictive Control (CMPC) to optimize the flow of physical goods throughout a network of supply chain nodes, utilizing a Mixed-Integer Linear Programming (MILP) approach to determine the optimal decision variables. Specifically, a Current State CMPC model was created to reflect the current outbound logistic network at Heineken Zoeterwoude, where information asymmetries are known to impact the accuracy of the outbound logistic planning tool. The Current State model was compared against a Future State model, where real-time data is available, thereby eliminating the aforementioned information asymmetries. By assessing four key performance indicators, it was found that the Future State model enables considerably better performance of the logistic network, even during peak production.

Offshore wind farms are increasing in size and moving further from shore. Service operation vessels (SOVs) are used for offshore wind operation and maintenance (O&M) at these large far offshore sites. These large vessels typically have a smaller daughter craft (DC) on board that can assist them. This DC is however too small to provide the seakeeping capabilities needed at most far offshore sites, causing it to become essentially unusable. Previous studies at Siemens Gamesa Renewable Energy (SGRE) have looked into improving the capabilities of the DC while considering the constraints of the SOV, this was deemed insufficiently possible by Brans (2021). The second study looked at increasing the size of the DC, which saw significant improvements (Kamerbeek, 2022). The work of Kamerbeek (2022) however raises new questions such as what is the optimum number of these larger DCs? Would another type of craft serve as a better mothership or DC? Is having the mothership perform maintenance the most efficient? SGRE is therefore interested in exploring mother-daughter concepts to perform offshore wind farm O&M activities at large far offshore wind farms, to see if these can outperform the status quo. A mothership is the home of the technicians offshore and the daughters are the craft that bring the technicians from the mothership to and from the turbines. The main research question is therefore: What method can best be used to explore the design-space of mother-daughter concepts for offshore wind farm O&M? This research first focuses on understanding offshore wind farm O&M and finding the most important restrictions and challenges that need to be taken into account within a model. This has been done through a literature review and discussions with experts from SGRE. The work then focuses on selecting a modeling method and explaining the proposed method. This method is validated using a comparison with a real-life wind farm. A case study is done at the end using a dummy wind farm to demonstrate the workings of the method. The method uses a discrete-event simulation that simulates the transport of technicians to and from the turbines to estimate the performance of the concepts. Any wind farm, turbine failure rates, or fleet can be inserted into the model for analysis to ensure a wide range of applications. The performance of the fleets is assessed based on the estimated downtime/availability and emission estimates that the model produces. The financial and technical feasibility should be evaluated in the next stage when a selection of promising solutions has been made based on this first logistical analysis of the fleets. The visits are planned within the model based on the weather conditions, number of available technicians, craft availability, and the evacuation requirement. The design space of mother-daughter concepts should be explored by running the model using the exploratory set of fleet configurations and inputting various wind farm layouts with varying realistic visit agendas and weather conditions. The output of each of these cases should then be analyzed by dividing all the fleet configurations into groups based on the craft each fleet contains. This grouping allows the performance of each type of fleet to be compared to one another, while the performance difference within the groups shows the effects of different transfer limits. The analysis should then focus on identifying cross-over points between different configurations and on selecting specific fleets based on performance and expected configuration cost.

Offshore wind farms are increasing in size and moving further from shore. Service operation vessels (SOVs) are used for offshore wind operation and maintenance (O&M) at these large far offshore sites. These large vessels typically have a smaller daughter craft (DC) on board that can assist them. This DC is however too small to provide the seakeeping capabilities needed at most far offshore sites, causing it to become essentially unusable. Previous studies at Siemens Gamesa Renewable Energy (SGRE) have looked into improving the capabilities of the DC while considering the constraints of the SOV, this was deemed insufficiently possible by Brans (2021). The second study looked at increasing the size of the DC, which saw significant improvements (Kamerbeek, 2022). The work of Kamerbeek (2022) however raises new questions such as what is the optimum number of these larger DCs? Would another type of craft serve as a better mothership or DC? Is having the mothership perform maintenance the most efficient? SGRE is therefore interested in exploring mother-daughter concepts to perform offshore wind farm O&M activities at large far offshore wind farms, to see if these can outperform the status quo. A mothership is the home of the technicians offshore and the daughters are the craft that bring the technicians from the mothership to and from the turbines. The main research question is therefore: What method can best be used to explore the design-space of mother-daughter concepts for offshore wind farm O&M? This research first focuses on understanding offshore wind farm O&M and finding the most important restrictions and challenges that need to be taken into account within a model. This has been done through a literature review and discussions with experts from SGRE. The work then focuses on selecting a modeling method and explaining the proposed method. This method is validated using a comparison with a real-life wind farm. A case study is done at the end using a dummy wind farm to demonstrate the workings of the method. The method uses a discrete-event simulation that simulates the transport of technicians to and from the turbines to estimate the performance of the concepts. Any wind farm, turbine failure rates, or fleet can be inserted into the model for analysis to ensure a wide range of applications. The performance of the fleets is assessed based on the estimated downtime/availability and emission estimates that the model produces. The financial and technical feasibility should be evaluated in the next stage when a selection of promising solutions has been made based on this first logistical analysis of the fleets. The visits are planned within the model based on the weather conditions, number of available technicians, craft availability, and the evacuation requirement. The design space of mother-daughter concepts should be explored by running the model using the exploratory set of fleet configurations and inputting various wind farm layouts with varying realistic visit agendas and weather conditions. The output of each of these cases should then be analyzed by dividing all the fleet configurations into groups based on the craft each fleet contains. This grouping allows the performance of each type of fleet to be compared to one another, while the performance difference within the groups shows the effects of different transfer limits. The analysis should then focus on identifying cross-over points between different configurations and on selecting specific fleets based on performance and expected configuration cost.

Frugal innovation, an innovation philosophy encapsulating a significant reduction of costs and focus on core functionality of products is used by companies across the globe to reach expanded markets. Nevertheless, manufacturing processes seem to have largely been excluded from frugal innovation applications. Reconfigurable manufacturing systems offer large opportunities for increasing both the efficiency and flexibility of production systems yet have not considered manufacturing sustainability or resource-constraints. The combination of frugal and reconfigurable manufacturing into frugal, reconfigurable manufacturing systems (F-RMSs) therefore inherently offers opportunities to make frugal manufacturing viable and RMSs less wasteful. F-RMSs are explored in this paper. The opportunities inherent in their combination are explored, the exact meaning of F-RMSs delineated and criteria for its success defined. A list of core characteristics and enablers is also defined to further distinguish the F-RMS as a manufacturing system. As such the F-RMS is fully conceptualized. Subsequently, a design framework for F-RMSs is defined based on this definition and criteria. In this way F-RMS design is facilitated and its eventual implementation enabled. The framework is focused on a requirements gathering and basic design step, where advanced design and implementation guidelines are defined on a case-by-case basis. The thesis is finalized with a set of case studies where the framework is carried out at different companies to (re)design an F-RMS. The functioning of the F-RMS is thereby validated, with the opportunities inherent in their combination recognized in the practical designs created.

Frugal innovation, an innovation philosophy encapsulating a significant reduction of costs and focus on core functionality of products is used by companies across the globe to reach expanded markets. Nevertheless, manufacturing processes seem to have largely been excluded from frugal innovation applications. Reconfigurable manufacturing systems offer large opportunities for increasing both the efficiency and flexibility of production systems yet have not considered manufacturing sustainability or resource-constraints. The combination of frugal and reconfigurable manufacturing into frugal, reconfigurable manufacturing systems (F-RMSs) therefore inherently offers opportunities to make frugal manufacturing viable and RMSs less wasteful. F-RMSs are explored in this paper. The opportunities inherent in their combination are explored, the exact meaning of F-RMSs delineated and criteria for its success defined. A list of core characteristics and enablers is also defined to further distinguish the F-RMS as a manufacturing system. As such the F-RMS is fully conceptualized. Subsequently, a design framework for F-RMSs is defined based on this definition and criteria. In this way F-RMS design is facilitated and its eventual implementation enabled. The framework is focused on a requirements gathering and basic design step, where advanced design and implementation guidelines are defined on a case-by-case basis. The thesis is finalized with a set of case studies where the framework is carried out at different companies to (re)design an F-RMS. The functioning of the F-RMS is thereby validated, with the opportunities inherent in their combination recognized in the practical designs created.