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Date: 2023-05-30 Level: Master thesis in Business Administration, 15 cr Institution: School of Business, Society and Engineering, Mälardalen University Authors: Ramak Amyari Khamneh (84/01/29), Aymen Safi (00/03/27) Title: Artificial Intelligence as a Catalyst for Supply Chain Resilience: A Qualitative Study Comparing Scania and Volvo in the Construction Equipment Industry Supervisor: Emre Yildiz Keywords: Artificial Intelligence (AI), Supply Chain Resilience, Construction Equipment Industry, Disruptions, Agility, Redundancy Research question: How do Scania and Volvo interpret and implement Artificial Intelligence (AI) technologies to enhance supply chain resilience and mitigate disruptions in the construction equipment industry? Purpose: The purpose of this master thesis is to investigate how Scania and Volvo interpret and implement AI technologies to enhance supply chain resilience and mitigate disruptions in the construction equipment industry. Method: Qualitative Conclusion: The conclusion of the master thesis is that Scania and Volvo have successfully implemented AI technologies to enhance supply chain resilience in the construction equipment industry, despite challenges, and see AI as a critical component for future supply chain strategies.

Vital societal functions are as the name suggests critical for the continued function of society. One of these functions is hospitals. The purpose of this paper is to investigate continuity management within hospitals. Regulations and laws regarding the Swedish health system will be presented along with an overview of how hospital continuity management works today. A topic that will be discussed in depth is disruptions, especially power outages and disruptions in staffing. These disruptions will be further investigated through a survey where hospital staff can define how different disruption scenarios relate to each other based on severity and the given timeframe for the disruption. A case study will be presented regarding how hospitals in Region Skåne handle continuity management. The results suggest that there are several indexes to measure hospital resilience. The survey presented in this report could be one of these in the future, but there was not enough data from this report alone to evaluate its success. The results also suggest that there are some regional differences in how continuity management is done within hospitals which can be problematic for the central leadership. According to the case study power outages are well understood however staff shortages are not equally prioritized in the continuity planning. Future developments regarding continuity management should include a deepened understanding of implementing personnel insights in the decision-making process.

This Editorial Note accompanies the special issue devoted to the development of new concepts, theories and methods that address reliability and resilience related to the planning, dynamic operation, and level of service of novel mobility systems. This special issue on 'Reliability and Resilience of Emerging Mobility Systems' consists of seven papers which are dedicated to methodological and theoretical developments as well as advanced applications in this domain. Several of the contributions originated from works presented at INSTR2021 (the 8th International Symposium on Transport Network Reliability). In this Editorial note we reflect on the contributions made in each of the articles included in this special issue., QC 20230404

The purpose of this phenomenological study was to discover foster parent factors contributing to foster care disruptions. Disruptions of foster care children are detrimental to the safety and well-being of the children. There are implications of foster care disruptions producing short- and long-term negative outcomes for children and families. Research indicates the emotional trauma effects of placement instability negatively impact the child’s relationships, ability to form attachments, educational outcomes, and mental and developmental stability. Foster parent factors have been identified that predict the likelihood of the parents disrupting the child’s placement and strategies for increasing placement stability in various studies. Further exploration on understanding why foster parents disrupt placements should be considered in effort to increase placement stability and reduce foster care children’s negative impact of placement moves.

Time management is crucial for liner shipping services. A variety of unexpected events can disrupt liner shipping schedules. A real-time port capacity analysis and rescheduling the original ship operations would be necessary to counteract the negative effects of such disruptions. Different ship schedule recovery options can be adopted in response to disruptive events (e.g., ship sailing speed adjustment, skipping of disrupted ports). However, shipping lines face conflicting decisions when selecting ship schedule recovery options. As an example, the commonly-used ship speeding-up option could effectively reduce delays during the voyage but would increase the fuel cost. Similarly, the skipping of disrupted ports may substantially decrease the associated delays but would incur additional costs associated with supply chain disruptions and misconnected cargo. Nevertheless, there is a lack of analytical methods that enable the evaluation of competing objectives in ship schedule recovery and effective multi-objective solution approaches. Therefore, this study proposes a novel multi-objective model for ship schedule recovery that aims not only to minimize the total late ship arrivals at ports but also to minimize the total profit loss due to disruptive events that may occur at sea and/or at ports. An epsilon-constraint-based exact optimization algorithm is adopted to obtain optimal Pareto Fronts. The computational experiments conducted for a real-life transit route demonstrate that the adopted exact optimization algorithm is able to generate Pareto Fronts in a timely manner. Moreover, the conducted sensitivity analyses provide interesting insights regarding the effects of different disruption types and unit fuel costs on ship schedule recovery., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., System Engineering

In the wake of the 2015 Paris Agreement on climate change, global efforts have intensified to reduce carbon emissions and transition to renewable energy sources such as solar and wind power. However, the asymmetry in energy production and consumption among nations, coupled with the seasonal and temporal intermittency and geographical variations of renewables, has highlighted the need for efficient energy transport solutions. Hydrogen has emerged as a promising candidate due to its high energy density and the fact that it only produces water when burned. Governments, both at the national and international levels, have outlined ambitious roadmaps for green hydrogen production and utilization, as seen in the EU's REPowerEU package aligned with the EU Green Deal and Japan's "Basic H2 strategy." Two prominent importers of hydrogen, Japan and The Netherlands, have been actively involved in shaping the future of international green hydrogen supply chains (IGHSC). However, as plans for IGHSC development gain momentum, so does the recognition of the need for resilient characteristics within these supply chains. They must be designed to withstand, adapt to, and recover from unexpected disruptions effectively. This research aims to address this need by developing a guideline for establishing a resilience design methodology specific to IGHSC, using Japan and The Netherlands as examples of significant future importers. The primary research question guiding this thesis is: What guidelines can be established to design and maintain resilience within an international green hydrogen supply chain, with Japan and The Netherlands as exploratory importers? The research approach combines extensive literature review, analysis, and interviews within a qualitative exploratory framework. A theoretical framework was constructed to uncover the interconnections between various theories and fields of study. This framework not only unveiled previously unnoticed associati, Complex Systems Engineering and Management (CoSEM)

This paper introduces the hub location problem under interhub link failures, a hub location problem in which activated interhub links may fail with a given probability. Two different optimization models are studied, which construct hub backbone networks protected under interhub link disruptions by imposing that, for each commodity, an addi-tional routing path exists besides its original routing path. Both models consider the minimi-zation of the fixed costs of the activated hubs and interhub links plus the expected value of the routing costs of the original and alternative paths. The first model builds explicitly the alternative routing paths, whereas the second model guarantees that, for each commodity, at least one alternative path exists using a large set of connectivity constraints although the alternative paths are not built explicitly. The results of extensive computational testing allow us to analyze the performance of the two proposed models and to evaluate the extra cost required to design a robust backbone network under interhub link failures. The obtained results support the validity of the proposal.

Purpose - The purpose of this study is to explore order fulfilment under the pressure of disruptionin the supply chain of international private organisations in the context of economic sanctions. Aconcept’s development was intended with the newest academic stud ies when the paper was written. Methodology and approach - It is an empirical research which uses qualitative methods ofresearch. The methods are an integrative literature review and case studies with interviews ofcompanies’ workers on companies facing e nvironmental and economic sanctions. Findings - The private companies prepare the supply chain disruptions mainly after encounteringsuch problems. The strategies against the disruptions amongst the network improve the resilient.The risk mitigation and th e management of this type of crisis are discovered in this study. Research limitations and implications - The low number of respondents and authors reduces theimpact and the possibilities of the research. The methods used limit the results as well as thesampling method. Practical implications - The theories and strategies built from previous researches are facing thecases of companies. And it shows that the access to various markets by the companies have alsoeffects on the reactivity of the supply chain of the companies. Originality or value - The context of supply chain disruptions in environmental disruptions andeconomic sanctions in the case of European sanctions against the Russian federation and coups inAfrica are explored. Type of paper - Master thesis with empirical research.

This Editorial Note accompanies the special issue devoted to the development of new concepts, theories and methods that address reliability and resilience related to the planning, dynamic operation, and level of service of novel mobility systems. This special issue on ‘Reliability and Resilience of Emerging Mobility Systems’ consists of seven papers which are dedicated to methodological and theoretical developments as well as advanced applications in this domain. Several of the contributions originated from works presented at INSTR2021 (the 8th International Symposium on Transport Network Reliability). In this Editorial note we reflect on the contributions made in each of the articles included in this special issue., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Transport and Planning

Date: 2023-05-30 Level: Master thesis in Business Administration, 15 cr Institution: School of Business, Society and Engineering, Mälardalen University Authors: Ramak Amyari Khamneh (84/01/29), Aymen Safi (00/03/27) Title: Artificial Intelligence as a Catalyst for Supply Chain Resilience: A Qualitative Study Comparing Scania and Volvo in the Construction Equipment Industry Supervisor: Emre Yildiz Keywords: Artificial Intelligence (AI), Supply Chain Resilience, Construction Equipment Industry, Disruptions, Agility, Redundancy Research question: How do Scania and Volvo interpret and implement Artificial Intelligence (AI) technologies to enhance supply chain resilience and mitigate disruptions in the construction equipment industry? Purpose: The purpose of this master thesis is to investigate how Scania and Volvo interpret and implement AI technologies to enhance supply chain resilience and mitigate disruptions in the construction equipment industry. Method: Qualitative Conclusion: The conclusion of the master thesis is that Scania and Volvo have successfully implemented AI technologies to enhance supply chain resilience in the construction equipment industry, despite challenges, and see AI as a critical component for future supply chain strategies.

The COVID-19 pandemic exposed the existential public health and economic fragilities of the civil aviation industry. To prevent future public health disruptions, the civil aviation industry is gaining interest in becoming more “resilient” but rarely elaborates on its meaning, hampering decision-making and strategy development. When looking into the academic literature it seems that a proliferation of resilience-related concepts occurred. Although enriching resilience, it also dilutes its meaning and reduces its use for practice. This paper aims to create concept clarity regarding resilience by proposing a categorization of resilience. Based upon a scoping review, this categorization dissects resilience into four reoccurring aspects: fragility, robustness, adaptation, and transformation. This categorization is expected to support sensemaking in disruptive times while assisting decision-making and strategy development on resilience. When applying this categorization in the civil aviation and public health context, the transformative aspect seems underused. Further research will focus on maturing the categorization of resilience and its use as a sensemaking tool., Marketing and Consumer Research, Applied Ergonomics and Design

The exclusive and excessive use of long-distance road transportation is not suitable way to reduce the negative environmental impacts of logistics systems. Intermodal transport, combining road with other transport modes, has the potential to reduce both operating costs and carbon footprints. One of the reasons for the low share of intermodal transport is its requirement for the coordination of scheduled transport services that can result in reducing reliability in case of disruptions due to the arrival of new shipment orders, fluctuations in shipment quantities, delays, and service cancellations within the network. This calls for reliable and efficient algorithms to replan the shipments’ distribution. In this paper, the replanning problem is formulated as a path-based multi-commodity network flows. We provide two different network topologies, one of which is based on a time–space network, while the other embeds time aspect in a highly scalable alternative structure to large transportation networks. We propose a column generation method whose pricing sub-problems are presented as resource constrained shortest path problem solved via a tailored label-correcting algorithm. We look at the pros and cons of complete and partial replanning in case of disruption and provide managerial insights for intermodal networks. An extensive set of computational experiments is presented on realistic instances being generated with the consultation of our industrial partners for a logistic network including railways, waterways, and roads. The promising outcomes validate the efficiency of the proposed approach that can be easily adjusted to real-time intermodal logistic replanning., Transport and Planning

During railways operations, unplanned events might occur which can result in rail traffic being heavily impacted. The paper proposes a passenger-centred resilience assessment for disruption scenarios which consist of multiple simultaneous disruptions. It combines train traffic operations, passenger flows and network restoration. To evaluate resilience, an optimization-based approach has been developed for solving the new infrastructure restoration and transport management (IRTM) problem. Additionally, this approach develops mitigation plans for the best infrastructure restoration and traffic recovery and it captures the time-dependent transport network performance during disruptions. The approach is general with respect to types of disruptions, and can be applied for evaluation against short disruptions (1–2 h) as well as more substantial ones (multiple days or weeks). The performance of the proposed approach has been demonstrated on a Dutch railway network. Furthermore, the resilience of the system is assessed against the critical infrastructure disruption scenarios in the network. This optimization-based approach shall enable decision makers to quantify accurately impacts of multiple disruptions by considering the created inconveniences to passengers in the railway operation due to these disruptions., Transport and Planning

Airlines frequently deal with unexpected disruptions, which have to be resolved in order to resume their operations again. Decision-support tools help airlines with disruption management. However, long computational times are associated with integrated recovery models that compute globally optimal solutions, which makes these tools unfit for large airlines. Faster sequential approaches have been proposed, which recover one resource at a time, but often only provide local optima. This paper presents a real-time decision-support tool to solve the integrated airline recovery problem. The model simultaneously recovers the schedule and allocates aircraft and pilot pairs to the flights, while minimizing additional incurred costs. Passengers are implicitly recovered by considering missed connections. Recovery actions include delaying and cancelling flights, swapping aircraft, and swapping, deadheading or using reserve crew. A machine-learned ranking algorithm reduces the computational complexity of the problem by selecting a subset of the resources that are likely to be involved in the recovery plan, such that only part of the network is considered. The decision-support tool was evaluated on disruption scenarios of one of the largest airlines in the world: Delta Airlines. The results show that the machine learning selection reduces the average computational time 15- fold compared to the integrated recovery model that uses the complete network, increasing the percentage of solutions computed under two minutes from 13% to 96%. The proposed model is able to find globally optimal solutions in 58% of the cases and yields similar results in terms of delays, but more flight cancellations in comparison with the globally optimal solutions. The proposed integrated model found a feasible solution to all disruption instances, while a benchmarked sequential model returned infeasible solutions in 4.4% of the cases. Besides, the sequential model produces 68% more flight cancellations, 4, Aerospace Engineering | Air Transport and Operations

Globalisation and outsourcing have exacerbated the complexity of supply chains (Christopher, 2016). As a result, new business models have emerged to reduce the complexity of the supply chain by utilising supply chain management solutions. These business models serve as links in the supply chain that facilitate the integration of the functions of the primary organisation with those of other organisations. When disruptions occur in the supply chain, several parties are impacted. In this situation, supply chain and risk management methodologies can assist in assessing internal and external aspects during disruptive events. To understand the perspective of logistics service providers, this thesis examines Schenker Dedicated Services and Samskip's perceptions of disruptive events, the effects of these events, and how resilience plans are developed. In this context, a logistics service provider is an underlying link that helps its clients by applying supply chain management strategies such as coordinating, integrating, establishing connections, and cooperating. We assembled a panel of supply chain practitioners with different roles at third-party and fourth-party logistics companies to investigate these factors. This panel had a role in our qualitative investigation and expressed their perspectives. It was discovered that their views of interruptions in the supply chain are comparable but slightly different. These discrepancies may be attributable to the company's business style, logistical networks, and geographic location., Globalisering och outsourcing har gjort leveranskedjorna svårare (Christopher, 2016). Följaktligen har det växt fram nya affärsmodeller för att minimera komplexiteten i försörjningskedjan genom försörjningskedjehanterings verktyg. Dessa affärsmodeller fungerar som länkar i försörjningskedjan som i sin tur hjälper till att integrera den primära organisationens funktioner i andra organisationer. När störningar uppstår i försörjningskedjan påverkas många inblandade parter. I detta fall kan tillvägagångssätten för försörjningskedje - och riskhantering hjälpa till att mäta de interna och externa faktorerna under störningar. Schenker Dedicated Services och Samskips utformar den underliggande länken i försörjningskedjan. Detta leder till ett fokus på hanteringen av försörjningskedjan genom att samordna, integrera, upprätta länkar och samarbeta. Genom att undersöka Schenker Dedicated Services och Samskips uppfattning om störande händelser, dess effekter och hur motståndsplaner utformas fastställs logistiktjänsteleverantörernas perspektiv. För att undersöka dessa faktorer valde vi en grupp av personer som är insatta med roller inom Schenker Dedicated Services som är ett fjärdepartslogistik företag och Samskip som är ett företag med inslag av tredjepartslogistik och fjärdepartslogistiks verksamhet. Gruppen var med i vår kvalitativa studie och delade sina uppfattningar kring ämnet. Det visade sig att de har liknande uppfattningar om störningar i leveranskedjan men med små skillnader. Dessa skillnader kan ha kopplingar till arten av företagets affärsmodell, deras logistiska nätverk såväl som deras geografiska område.

Background: Reshoring is a growing phenomenon that refers to a company’s decision to move production back from a previously offshored location. There are many drivers and barriers to such decisions that display an increased complexity for managers. It gets even more challenging in a world with high levels of uncertainty shown in the past decade. Purpose: This study aims to investigate the drivers and barriers of reshoring and how managers perceive the risk of disruptive events as a driver of reshoring. Method: This study uses a qualitative method and deductive approach, where empirical evidence was collected through semi-structured interviews with eight managers at clothing companies. Conclusion: The findings of this study confirm several already established drivers and barriers to reshoring in the particular context of the clothing industry. Furthermore, the study shows that managers perceive an increased willingness to reshore as a response to disruptive events. This was to a large extent due to long lead times and higher coordination costs. Managers can use the findings as support in making decisions of where to locate their production.

Background: The pandemic disruption caused by COVID-19, which began at the end of 2019, hashad an impact on economies across the globe. A profound impact has been noticed in the Procurementfunction, which has suffered from supply disruptions. The importance of the procurement function indisruption management is stressed through its role as the window to the supplier base. Supply chain disruptions force firms to evaluate and create capabilities to mitigate the effect of risk sources andimprove resilience. By building resilience into supply networks, companies are better prepared fordisruptions and can thus bounce back easier and quicker. Purpose: The purpose of this research was to explore how procurement strategies have changed under the COVID-19 disruption to become more resilient. We focus on which changes firms have implemented to make their procurement more resilient, and why. To draw conclusions, proactive strategies the companies had in place, as well as reactive strategies that they implemented after the disruption, are explored. Method: This research was conducted through a qualitative case study design of 8 firms which were affected by disruptions emanating from the COVID-19 pandemic. Insights and facts on the purpose were obtained through interviews with 10 procurement professionals working in these case companies.The findings were analysed with the Supply Chain Resilience (SCRES) literature and theory. A crosscase analysis ultimately led to the final conclusions. Conclusion: All informants noted an improvement in their situation after implementing reactive strategy changes. The sample seemed to indicate a short-term perspective on the crisis, two years intothe pandemic. Long-term thinking or strategies are a rarity. The disruptions caused by the pandemic have improved risk-management and disruption-thinking. However, in most of our sample, this has hardly materialized into the development of mitigation strategies for future disruptions. The resilience-foc

The first year of university constitutes a crucial stage in students’ adjustment to university. The first-year experience (FYE) of students in Chile is the subject of public policy efforts and scholarly discussions about access to higher education and retention. While there have been some empirical studies investigating student attrition and retention in Chile, the research to date has been narrow in scope, focussing mainly on factors affecting access and attrition. There is limited research that captures the complexity of students’ experiences in the first year of university, and particularly their experiences of university in times of major social disruption. This mixed-methods study investigated the first-year student experience in Chile during a period of mass demonstrations and the Covid-19 pandemic and analysed the factors influencing students’ transition and adjustment to universities over two years. One hundred and seventy-nine first-year students responded to an online survey about their university experience. Eight students participated in a series of semi-structured interviews over the first two years of their university studies. The findings suggest that commencing university studies with clear goals fostered students’ motivation and engagement in their studies. Peer interactions encouraged students’ sense of belonging to university, providing vital academic and emotional support, especially during times of isolation. Supportive interactions with teachers and adjusting teaching to accommodate students’ circumstances promoted students’ engagement with their studies and supported their wellbeing in challenging times. The findings of the present study reaffirm that supportive experiences with peers and teachers can facilitate students’ transition and adjustment to university. This aligns with international evidence and highlights the critical role that peers and teachers play in challenging times. The findings provide insights into the complexity of student

The environment in which companies operate is increasingly volatile and complex. This results in an increased exposure to disruptions. Past disruptions have especially affected procurement. Thus, companies need to prepare for disruptions. The preparedness for disruptions in the context of procurement is significantly influenced by the design of the procurement strategy. However, a high number of purchased articles and a variety of influencing factors lead to high complexity in procurement. The systematic design of the procurement strategy should therefore take into account the criticality of the purchased articles. This enables to focus on the purchased articles that have a high impact on the disruption preparedness. Existing approaches regarding the design of the procurement strategy in uncertain environments either lack practical applicability and objective evaluation or focus on the criticality of raw materials rather than of purchased articles. Therefore, a data-based approach for the systematic design of the procurement strategy in the context of the Internet of Production has been proposed. One central aspect of this approach is the identification of success-critical purchased articles. Thus, this paper proposes a framework for characterizing purchased articles regarding supply risks by combining two systematic analyses. First, a systematic literature review is performed to answer the question of what factors can be used to describe the supply risks of purchased articles. The results are analyzed regarding sources and impacts of risks and thus contribute to a structured characterization of supply risks. Second, existing criticality assessment approaches for raw materials are analyzed to identify categories and indicators that describe purchased articles. The results of both reviews provide the basis for linking product characteristics with supply risks and assessing product criticality which will be integrated into an app prototype.

Companies operate in an increasingly volatile environment where different developments like shorter product lifecycles, the demand for customized products and globalization increase the complexity and interconnectivity in supply chains. Current events like Brexit, the COVID-19 pandemic or the blockade of the Suez canal have caused major disruptions in supply chains. This demonstrates that many companies are insufficiently prepared for disruptions. As disruptions in supply chains are expected to occur even more frequently in the future, the need for sufficient preparation increases. Increasing resilience provides one way of dealing with disruptions. Resilience can be understood as the ability of a system to cope with disruptions and to ensure the competitiveness of a company. In particular, it enables the preparation for unexpected disruptions. The level of resilience is thereby significantly influenced by actions initiated prior to a disruption. Although companies recognize the need to increase their resilience, it is not systematically implemented. One major challenge is the multidimensionality and complexity of the resilience construct. To systematically design resilience an understanding of the components of resilience is required. However, a common understanding of constituent parts of resilience is currently lacking. This paper, therefore, proposes a general framework for structuring resilience by decomposing the multidimensional concept into its individual components. The framework contributes to an understanding of the interrelationships between the individual components and identifies resilience principles as target directions for the design of resilience. It thus sets the basis for a qualitative assessment of resilience and enables the analysis of resilience-building measures in terms of their impact on resilience. Moreover, an approach for applying the framework to different contexts is presented and then used to detail the framework for the context of pro

Companies operate in an increasingly volatile environment where different developments like shorter product lifecycles, the demand for customized products and globalization increase the complexity and interconnectivity in supply chains. Current events like Brexit, the COVID-19 pandemic or the blockade of the Suez canal have caused major disruptions in supply chains. This demonstrates that many companies are insufficiently prepared for disruptions. As disruptions in supply chains are expected to occur even more frequently in the future, the need for sufficient preparation increases. Increasing resilience provides one way of dealing with disruptions. Resilience can be understood as the ability of a system to cope with disruptions and to ensure the competitiveness of a company. In particular, it enables the preparation for unexpected disruptions. The level of resilience is thereby significantly influenced by actions initiated prior to a disruption. Although companies recognize the need to increase their resilience, it is not systematically implemented. One major challenge is the multidimensionality and complexity of the resilience construct. To systematically design resilience an understanding of the components of resilience is required. However, a common understanding of constituent parts of resilience is currently lacking. This paper, therefore, proposes a general framework for structuring resilience by decomposing the multidimensional concept into its individual components. The framework contributes to an understanding of the interrelationships between the individual components and identifies resilience principles as target directions for the design of resilience. It thus sets the basis for a qualitative assessment of resilience and enables the analysis of resilience-building measures in terms of their impact on resilience. Moreover, an approach for applying the framework to different contexts is presented and then used to detail the framework for the context of pro

The COVID-19 global pandemic has had severe, unpredictable and synchronous impacts on all levels of perishable food supply chains (PFSC), across multiple sectors and spatial scales. Aquaculture plays a vital and rapidly expanding role in food security, in some cases overtaking wild caught fisheries in the production of high-quality animal protein in this PFSC. We performed a rapid global assessment to evaluate the effects of the COVID-19 pandemic and related emerging control measures on the aquaculture supply chain. Socio-economic effects of the pandemic were analysed by surveying the perceptions of stakeholders, who were asked to describe potential supply-side disruption, vulnerabilities and resilience patterns along the production pipeline with four main supply chain components: a) hatchery, b) production/processing, c) distribution/logistics and d) market. We also assessed different farming strategies, comparing land- vs. sea-based systems; extensive vs. intensive methods; and with and without integrated multi-trophic aquaculture, IMTA. In addition to evaluating levels and sources of economic distress, interviewees were asked to identify mitigation solutions adopted at local / internal (i.e., farm-site) scales, and to express their preference on national / external scale mitigation measures among a set of a priori options. Survey responses identified the potential causes of disruption, ripple effects, sources of food insecurity, and socio-economic conflicts. They also pointed to various levels of mitigation strategies. The collated evidence represents a first baseline useful to address future disaster-driven responses, to reinforce the resilience of the sector and to facilitate the design reconstruction plans and mitigation measures, such as financial aid strategies.

Background: The pandemic disruption caused by COVID-19, which began at the end of 2019, hashad an impact on economies across the globe. A profound impact has been noticed in the Procurementfunction, which has suffered from supply disruptions. The importance of the procurement function indisruption management is stressed through its role as the window to the supplier base. Supply chain disruptions force firms to evaluate and create capabilities to mitigate the effect of risk sources andimprove resilience. By building resilience into supply networks, companies are better prepared fordisruptions and can thus bounce back easier and quicker. Purpose: The purpose of this research was to explore how procurement strategies have changed under the COVID-19 disruption to become more resilient. We focus on which changes firms have implemented to make their procurement more resilient, and why. To draw conclusions, proactive strategies the companies had in place, as well as reactive strategies that they implemented after the disruption, are explored. Method: This research was conducted through a qualitative case study design of 8 firms which were affected by disruptions emanating from the COVID-19 pandemic. Insights and facts on the purpose were obtained through interviews with 10 procurement professionals working in these case companies.The findings were analysed with the Supply Chain Resilience (SCRES) literature and theory. A crosscase analysis ultimately led to the final conclusions. Conclusion: All informants noted an improvement in their situation after implementing reactive strategy changes. The sample seemed to indicate a short-term perspective on the crisis, two years intothe pandemic. Long-term thinking or strategies are a rarity. The disruptions caused by the pandemic have improved risk-management and disruption-thinking. However, in most of our sample, this has hardly materialized into the development of mitigation strategies for future disruptions. The resilience-foc

Globalisation and outsourcing have exacerbated the complexity of supply chains (Christopher, 2016). As a result, new business models have emerged to reduce the complexity of the supply chain by utilising supply chain management solutions. These business models serve as links in the supply chain that facilitate the integration of the functions of the primary organisation with those of other organisations. When disruptions occur in the supply chain, several parties are impacted. In this situation, supply chain and risk management methodologies can assist in assessing internal and external aspects during disruptive events. To understand the perspective of logistics service providers, this thesis examines Schenker Dedicated Services and Samskip's perceptions of disruptive events, the effects of these events, and how resilience plans are developed. In this context, a logistics service provider is an underlying link that helps its clients by applying supply chain management strategies such as coordinating, integrating, establishing connections, and cooperating. We assembled a panel of supply chain practitioners with different roles at third-party and fourth-party logistics companies to investigate these factors. This panel had a role in our qualitative investigation and expressed their perspectives. It was discovered that their views of interruptions in the supply chain are comparable but slightly different. These discrepancies may be attributable to the company's business style, logistical networks, and geographic location., Globalisering och outsourcing har gjort leveranskedjorna svårare (Christopher, 2016). Följaktligen har det växt fram nya affärsmodeller för att minimera komplexiteten i försörjningskedjan genom försörjningskedjehanterings verktyg. Dessa affärsmodeller fungerar som länkar i försörjningskedjan som i sin tur hjälper till att integrera den primära organisationens funktioner i andra organisationer. När störningar uppstår i försörjningskedjan påverkas många inblandade parter. I detta fall kan tillvägagångssätten för försörjningskedje - och riskhantering hjälpa till att mäta de interna och externa faktorerna under störningar. Schenker Dedicated Services och Samskips utformar den underliggande länken i försörjningskedjan. Detta leder till ett fokus på hanteringen av försörjningskedjan genom att samordna, integrera, upprätta länkar och samarbeta. Genom att undersöka Schenker Dedicated Services och Samskips uppfattning om störande händelser, dess effekter och hur motståndsplaner utformas fastställs logistiktjänsteleverantörernas perspektiv. För att undersöka dessa faktorer valde vi en grupp av personer som är insatta med roller inom Schenker Dedicated Services som är ett fjärdepartslogistik företag och Samskip som är ett företag med inslag av tredjepartslogistik och fjärdepartslogistiks verksamhet. Gruppen var med i vår kvalitativa studie och delade sina uppfattningar kring ämnet. Det visade sig att de har liknande uppfattningar om störningar i leveranskedjan men med små skillnader. Dessa skillnader kan ha kopplingar till arten av företagets affärsmodell, deras logistiska nätverk såväl som deras geografiska område.

Background: Reshoring is a growing phenomenon that refers to a company’s decision to move production back from a previously offshored location. There are many drivers and barriers to such decisions that display an increased complexity for managers. It gets even more challenging in a world with high levels of uncertainty shown in the past decade. Purpose: This study aims to investigate the drivers and barriers of reshoring and how managers perceive the risk of disruptive events as a driver of reshoring. Method: This study uses a qualitative method and deductive approach, where empirical evidence was collected through semi-structured interviews with eight managers at clothing companies. Conclusion: The findings of this study confirm several already established drivers and barriers to reshoring in the particular context of the clothing industry. Furthermore, the study shows that managers perceive an increased willingness to reshore as a response to disruptive events. This was to a large extent due to long lead times and higher coordination costs. Managers can use the findings as support in making decisions of where to locate their production.

The environment in which companies operate is increasingly volatile and complex. This results in an increased exposure to disruptions. Past disruptions have especially affected procurement. Thus, companies need to prepare for disruptions. The preparedness for disruptions in the context of procurement is significantly influenced by the design of the procurement strategy. However, a high number of purchased articles and a variety of influencing factors lead to high complexity in procurement. The systematic design of the procurement strategy should therefore take into account the criticality of the purchased articles. This enables to focus on the purchased articles that have a high impact on the disruption preparedness. Existing approaches regarding the design of the procurement strategy in uncertain environments either lack practical applicability and objective evaluation or focus on the criticality of raw materials rather than of purchased articles. Therefore, a data-based approach for the systematic design of the procurement strategy in the context of the Internet of Production has been proposed. One central aspect of this approach is the identification of success-critical purchased articles. Thus, this paper proposes a framework for characterizing purchased articles regarding supply risks by combining two systematic analyses. First, a systematic literature review is performed to answer the question of what factors can be used to describe the supply risks of purchased articles. The results are analyzed regarding sources and impacts of risks and thus contribute to a structured characterization of supply risks. Second, existing criticality assessment approaches for raw materials are analyzed to identify categories and indicators that describe purchased articles. The results of both reviews provide the basis for linking product characteristics with supply risks and assessing product criticality which will be integrated into an app prototype.

Urban metro and tram networks are regularly subject to planned disruptions, including closures, resulting from the need to maintain and renew infrastructure. In this study, we first empirically analyse the passenger demand response to planned public transport disruptions based on individual passenger travel behaviour, based on which we infer generalised journey time and cost elasticities for different passenger groups and time periods of the day. Second, we develop a model which enables predicting public transport demand for individual origin-destination pairs affected by a closure. The model is trained based on the empirically observed travel behaviour. The proposed method is applied to a case study closure in Amsterdam, the Netherlands, based on which we empirically derive generalised journey time and generalised journey cost elasticities of − 0.99 and − 1.11, respectively. Our results suggest that passengers’ demand response is lower for frequent users of the public transport network, as well as during weekdays - especially during the peak periods. Arguably, this stems from a higher share of captive passengers with a mandatory journey purpose in these segments, who will continue making their journey nevertheless. During weekends - with typically higher shares of leisure related journeys - a much more pronounced demand response is found. The estimated neural network regression model is able to predict passenger demand during public transport closures with a high level of accuracy. This provides public transport agencies more precise insights into the impact of closures on their revenue losses and on the potential need for resources reallocation., Transport and Planning

During railways operations, unplanned events might occur which can result in rail traffic being heavily impacted. The paper proposes a passenger-centred resilience assessment for disruption scenarios which consist of multiple simultaneous disruptions. It combines train traffic operations, passenger flows and network restoration. To evaluate resilience, an optimization-based approach has been developed for solving the new infrastructure restoration and transport management (IRTM) problem. Additionally, this approach develops mitigation plans for the best infrastructure restoration and traffic recovery and it captures the time-dependent transport network performance during disruptions. The approach is general with respect to types of disruptions, and can be applied for evaluation against short disruptions (1–2 h) as well as more substantial ones (multiple days or weeks). The performance of the proposed approach has been demonstrated on a Dutch railway network. Furthermore, the resilience of the system is assessed against the critical infrastructure disruption scenarios in the network. This optimization-based approach shall enable decision makers to quantify accurately impacts of multiple disruptions by considering the created inconveniences to passengers in the railway operation due to these disruptions., Transport and Planning

Airlines frequently deal with unexpected disruptions, which have to be resolved in order to resume their operations again. Decision-support tools help airlines with disruption management. However, long computational times are associated with integrated recovery models that compute globally optimal solutions, which makes these tools unfit for large airlines. Faster sequential approaches have been proposed, which recover one resource at a time, but often only provide local optima. This paper presents a real-time decision-support tool to solve the integrated airline recovery problem. The model simultaneously recovers the schedule and allocates aircraft and pilot pairs to the flights, while minimizing additional incurred costs. Passengers are implicitly recovered by considering missed connections. Recovery actions include delaying and cancelling flights, swapping aircraft, and swapping, deadheading or using reserve crew. A machine-learned ranking algorithm reduces the computational complexity of the problem by selecting a subset of the resources that are likely to be involved in the recovery plan, such that only part of the network is considered. The decision-support tool was evaluated on disruption scenarios of one of the largest airlines in the world: Delta Airlines. The results show that the machine learning selection reduces the average computational time 15- fold compared to the integrated recovery model that uses the complete network, increasing the percentage of solutions computed under two minutes from 13% to 96%. The proposed model is able to find globally optimal solutions in 58% of the cases and yields similar results in terms of delays, but more flight cancellations in comparison with the globally optimal solutions. The proposed integrated model found a feasible solution to all disruption instances, while a benchmarked sequential model returned infeasible solutions in 4.4% of the cases. Besides, the sequential model produces 68% more flight cancellations, 4, Aerospace Engineering | Air Transport and Operations

In modern construction, collaboration has become a key element for the success of projects. Both clients and contractors are aware of the importance of maintaining a solid relationship. However, as collaboration is subject to ambiguous factors that influence both the content of the project and the social elements, it is proven to be difficult to achieve this mission. Elemental differences in the goals, ambitions and responsibilities of clients and contractors during projects still exist and cause differences in perception. One of the elements collaborations are subject to, are external factors. These are especially hard to deal with due to the fact that the occurrence of said factors is beyond the control of the project team. This research provides insight in this volatile environment with the aim to increase the resilience of collaborations by answering the question: “What external factors are present during construction projects that influence the collaboration between client and contractors and how can the impact of these events be reduced up-front?”. To answer this question, a Q-study is performed. As input for this study, a model of the project environment distinguishing the internal and external project environment is created. The model defines 8 domains of external factors which influence client-contractor collaboration: economic, technological and political -context, the parent organisation of both client and contractor, subcontractors, related projects & surroundings and lastly the stakeholders. From the Q-study four perspectives on external factors are retrieved, confirming the difference in perception of the external factors for individuals, based on their respective role and organisations in the collaboration. To reduce the influence of external factors on the dynamics within the project team, a framework of measures to create resilient collaborations is composed. The measures are divided in three categories: preliminary organisation, creating flexib, Civil Engineering | Construction Management and Engineering

The way in which time is produced and consumed during everyday life has crucial implications for sustainable consumption. Social practice approaches in particular have directed attention to the intersection of personal and collective temporalities as important for the patterning of everyday consumption. This article examines the temporal dynamics of daily practice-arrangement bundles experienced in “locked down” households in Germany, Ireland, Italy, Norway, and the UK during the COVID-19 pandemic. Drawing on 97 in-depth interviews with participants in all five countries, we investigate quotidian experiences of the breaking and (re-)making of daily routines in response to the pandemic. In doing so, we explore and document the temporal processes by which daily practice-arrangement bundles become undone, reassembled, and reconfigured. Our analysis reveals the institutional ordering of temporal relations between practices in terms of how they hang together, synchronize, or compete for householders’ time. Giving particular attention to socially differentiated lockdown experiences, we analyze how disruption-induced changes to social institutions and systems of provision impact the hanging together of daily practice-arrangement bundles and the strategies employed to restructure and rebundle them in unequal ways. We further consider varied experiences in temporal reorganizations of daily life that support sustainable consumption of food and mobility and reflect on the implications of the analysis for sustainability governance.

JOREK is a massively parallel fully implicit non-linear extended magneto-hydrodynamic (MHD) code for realistic tokamak X-point plasmas. It has become a widely used versatile simulation code for studying large-scale plasma instabilities and their control and is continuously developed in an international community with strong involvements in the European fusion research programme and ITER organization. This article gives a comprehensive overview of the physics models implemented, numerical methods applied for solving the equations and physics studies performed with the code. A dedicated section highlights some of the verification work done for the code. A hierarchy of different physics models is available including a free boundary and resistive wall extension and hybrid kinetic-fluid models. The code allows for flux-surface aligned iso-parametric finite element grids in single and double X-point plasmas which can be extended to the true physical walls and uses a robust fully implicit time stepping. Particular focus is laid on plasma edge and scrape-off layer (SOL) physics as well as disruption related phenomena. Among the key results obtained with JOREK regarding plasma edge and SOL, are deep insights into the dynamics of edge localized modes (ELMs), ELM cycles, and ELM control by resonant magnetic perturbations, pellet injection, as well as by vertical magnetic kicks. Also ELM free regimes, detachment physics, the generation and transport of impurities during an ELM, and electrostatic turbulence in the pedestal region are investigated. Regarding disruptions, the focus is on the dynamics of the thermal quench (TQ) and current quench triggered by massive gas injection and shattered pellet injection, runaway electron (RE) dynamics as well as the RE interaction with MHD modes, and vertical displacement events. Also the seeding and suppression of tearing modes (TMs), the dynamics of naturally occurring TQs triggered by locked modes, and radiative collapses are being st, Energy Technology

JOREK is a massively parallel fully implicit non-linear extended magneto-hydrodynamic (MHD) code for realistic tokamak X-point plasmas. It has become a widely used versatile simulation code for studying large-scale plasma instabilities and their control and is continuously developed in an international community with strong involvements in the European fusion research programme and ITER organization. This article gives a comprehensive overview of the physics models implemented, numerical methods applied for solving the equations and physics studies performed with the code. A dedicated section highlights some of the verification work done for the code. A hierarchy of different physics models is available including a free boundary and resistive wall extension and hybrid kinetic-fluid models. The code allows for flux-surface aligned iso-parametric finite element grids in single and double X-point plasmas which can be extended to the true physical walls and uses a robust fully implicit time stepping. Particular focus is laid on plasma edge and scrape-off layer (SOL) physics as well as disruption related phenomena. Among the key results obtained with JOREK regarding plasma edge and SOL, are deep insights into the dynamics of edge localized modes (ELMs), ELM cycles, and ELM control by resonant magnetic perturbations, pellet injection, as well as by vertical magnetic kicks. Also ELM free regimes, detachment physics, the generation and transport of impurities during an ELM, and electrostatic turbulence in the pedestal region are investigated. Regarding disruptions, the focus is on the dynamics of the thermal quench (TQ) and current quench triggered by massive gas injection and shattered pellet injection, runaway electron (RE) dynamics as well as the RE interaction with MHD modes, and vertical displacement events. Also the seeding and suppression of tearing modes (TMs), the dynamics of naturally occurring TQs triggered by locked modes, and radiative collapses are being st

Recent developments have demonstrated the challenges and impacts of disruptions in supply chains. Current disruptions especially affected procurement and have indicated a lack of resilience. Resilience aims at being prepared, decreasing the impact, and enabling fast reactions and adaption in case of disruptions. The systematic design of resilience in procurement is significantly influenced by proactive and strategic actions before disruptions occur. Thus, the procurement strategy plays a major role when increasing resilience. The procurement strategy is influenced by various factors. Thus, a data-based approach for its systematic design is required. Based on the vision of the Internet of Production (IoP), this paper presents a data-based approach for designing procurement strategies. The IoP is a framework that enables cross-domain collaboration by providing semantically adequate and contextual data from production, development, and usage in real-time at an appropriate granularity. The presented approach is structured along the action research cycle and uses CRISP-DM to further detail the different steps. Moreover, the paper aims at analyzing the state of the art regarding the design of procurement strategy in uncertain environments and the identification of success-critical purchased articles. The paper also introduces the textile industry and its supply chains as a use case for the presented approach.

JOREK is a massively parallel fully implicit non-linear extended magneto-hydrodynamic (MHD) code for realistic tokamak X-point plasmas. It has become a widely used versatile simulation code for studying large-scale plasma instabilities and their control and is continuously developed in an international community with strong involvements in the European fusion research programme and ITER organization. This article gives a comprehensive overview of the physics models implemented, numerical methods applied for solving the equations and physics studies performed with the code. A dedicated section highlights some of the verification work done for the code. A hierarchy of different physics models is available including a free boundary and resistive wall extension and hybrid kinetic-fluid models. The code allows for flux-surface aligned iso-parametric finite element grids in single and double X-point plasmas which can be extended to the true physical walls and uses a robust fully implicit time stepping. Particular focus is laid on plasma edge and scrape-off layer (SOL) physics as well as disruption related phenomena. Among the key results obtained with JOREK regarding plasma edge and SOL, are deep insights into the dynamics of edge localized modes (ELMs), ELM cycles, and ELM control by resonant magnetic perturbations, pellet injection, as well as by vertical magnetic kicks. Also ELM free regimes, detachment physics, the generation and transport of impurities during an ELM, and electrostatic turbulence in the pedestal region are investigated. Regarding disruptions, the focus is on the dynamics of the thermal quench (TQ) and current quench triggered by massive gas injection and shattered pellet injection, runaway electron (RE) dynamics as well as the RE interaction with MHD modes, and vertical displacement events. Also the seeding and suppression of tearing modes (TMs), the dynamics of naturally occurring TQs triggered by locked modes, and radiative collapses are being studi, Peer Reviewed, Postprint (published version)

Place-based research faces multiple threats, including both natural and global health hazards and political conflicts, which may disrupt fieldwork. The current COVID-19 pandemic shows how these threats can drastically affect social-ecological research activities given its engagement with different local stakeholders, disciplines, and knowledge systems. The crisis reveals the need for adaptive research designs while also providing an opportunity for a structural shift towards a more sustainable and inclusive research landscape.

JOREK is a massively parallel fully implicit non-linear extended magneto-hydrodynamic (MHD) code for realistic tokamak X-point plasmas. It has become a widely used versatile simulation code for studying large-scale plasma instabilities and their control and is continuously developed in an international community with strong involvements in the European fusion research programme and ITER organization. This article gives a comprehensive overview of the physics models implemented, numerical methods applied for solving the equations and physics studies performed with the code. A dedicated section highlights some of the verification work done for the code. A hierarchy of different physics models is available including a free boundary and resistive wall extension and hybrid kinetic-fluid models. The code allows for flux-surface aligned iso-parametric finite element grids in single and double X-point plasmas which can be extended to the true physical walls and uses a robust fully implicit time stepping. Particular focus is laid on plasma edge and scrape-off layer (SOL) physics as well as disruption related phenomena. Among the key results obtained with JOREK regarding plasma edge and SOL, are deep insights into the dynamics of edge localized modes (ELMs), ELM cycles, and ELM control by resonant magnetic perturbations, pellet injection, as well as by vertical magnetic kicks. Also ELM free regimes, detachment physics, the generation and transport of impurities during an ELM, and electrostatic turbulence in the pedestal region are investigated. Regarding disruptions, the focus is on the dynamics of the thermal quench (TQ) and current quench triggered by massive gas injection and shattered pellet injection, runaway electron (RE) dynamics as well as the RE interaction with MHD modes, and vertical displacement events. Also the seeding and suppression of tearing modes (TMs), the dynamics of naturally occurring TQs triggered by locked modes, and radiative collapses are being st

JOREK is a massively parallel fully implicit non-linear extended magneto-hydrodynamic (MHD) code for realistic tokamak X-point plasmas. It has become a widely used versatile simulation code for studying large-scale plasma instabilities and their control and is continuously developed in an international community with strong involvements in the European fusion research programme and ITER organization. This article gives a comprehensive overview of the physics models implemented, numerical methods applied for solving the equations and physics studies performed with the code. A dedicated section highlights some of the verification work done for the code. A hierarchy of different physics models is available including a free boundary and resistive wall extension and hybrid kinetic-fluid models. The code allows for flux-surface aligned iso-parametric finite element grids in single and double X-point plasmas which can be extended to the true physical walls and uses a robust fully implicit time stepping. Particular focus is laid on plasma edge and scrape-off layer (SOL) physics as well as disruption related phenomena. Among the key results obtained with JOREK regarding plasma edge and SOL, are deep insights into the dynamics of edge localized modes (ELMs), ELM cycles, and ELM control by resonant magnetic perturbations, pellet injection, as well as by vertical magnetic kicks. Also ELM free regimes, detachment physics, the generation and transport of impurities during an ELM, and electrostatic turbulence in the pedestal region are investigated. Regarding disruptions, the focus is on the dynamics of the thermal quench (TQ) and current quench triggered by massive gas injection and shattered pellet injection, runaway electron (RE) dynamics as well as the RE interaction with MHD modes, and vertical displacement events. Also the seeding and suppression of tearing modes (TMs), the dynamics of naturally occurring TQs triggered by locked modes, and radiative collapses are being st, Energy Technology

Recent developments have demonstrated the challenges and impacts of disruptions in supply chains. Current disruptions especially affected procurement and have indicated a lack of resilience. Resilience aims at being prepared, decreasing the impact, and enabling fast reactions and adaption in case of disruptions. The systematic design of resilience in procurement is significantly influenced by proactive and strategic actions before disruptions occur. Thus, the procurement strategy plays a major role when increasing resilience. The procurement strategy is influenced by various factors. Thus, a data-based approach for its systematic design is required. Based on the vision of the Internet of Production (IoP), this paper presents a data-based approach for designing procurement strategies. The IoP is a framework that enables cross-domain collaboration by providing semantically adequate and contextual data from production, development, and usage in real-time at an appropriate granularity. The presented approach is structured along the action research cycle and uses CRISP-DM to further detail the different steps. Moreover, the paper aims at analyzing the state of the art regarding the design of procurement strategy in uncertain environments and the identification of success-critical purchased articles. The paper also introduces the textile industry and its supply chains as a use case for the presented approach.

Services, and failures associated with it, are nestled in systemic contexts. It is important to understand how disruptions might ripple out in services, as well as how actors influence disruptions and possible failures through their participation, as this can impact value creation. This paper reports the results of an interview study supported by a card mapping tool. The main contribution of this work is its generative methodological approach when exploring service disruptions from a systems lens. Using this method, we classify eight forms of disruption: request, query, hiccup, delay, mistake, flaw, breakdown and the unexpected, and associated systemic activation patterns. We suggest a disruption-activation ripple model and identify five tensions in responding to disruptions: competing priorities, dealing with difficult others, mismatching expectations, shouldering responsibility, and reluctant assistance. We posit that this generative tool can be used to understand the nature and extent of disruptions in situated service contexts. This understanding can provide direction on how to handle and/or absorb variety emerging in different interactions by clarifying frequency and predictability of certain kinds of disruptions in investigated contexts. We also argue that viewing service disruptions through a systems lens requires the designing of social service infrastructures that support employee relationships., Funding: This project received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 642116.

In large-scale urban agglomerations, heavy rail in the form of metro and commuter train serves as the backbone of the metropolitan public transport network. The objective of this paper is to investigate whether networks with strikingly different structure and development pattern exhibit different robustness properties in the event of random and targeted attacks. We adopt a complex network theory approach, investigating network performances under alternative sequential disruption scenarios corresponding to the successive closure of either stations or track segments. We also investigate the case where the removal of a network node or link implies the closure of all traversing lines Network performance is measured both in terms of the capacity of the network to function in terms of connectivity as well as the additional impedance induced for those that remain connected. An aggregate robustness indicator based on the integral of the deterioration of network performance is adopted. Three exemplary networks are selected, the urban rail networks of London, Shanghai and Randstad. These three networks offer showcases of short and long development patterns, mono- and polycentric agglomeration structures, including the largest and the oldest metropolitan heavy rail networks. The polycentric network of the Randstad was found the least robust in this analysis when compared to the more monocentric networks of London and Shanghai. The London network is in general more robust than the Shanghai network thanks to the presence of cycles beyond the core. Our findings provide more nuanced evidence on the relation between network structure and development pattern, and its robustness., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Transport and Planning

Disruptions in public transport can have major implications for passengers and service providers. Our study objective is to develop a generic approach to predict how often different disruption types occur at different stations of a public transport network, and to predict the impact related to these disruptions as measured in terms of passenger delays. We propose a supervised learning approach to perform these predictions, as this allows for predictions for individual stations for each time period, without the requirement of having sufficient empirical disruption observations available for each location and time period. This approach also enables a fast prediction of disruption impacts for a large number of disruption instances, hence addressing the computational challenges that rise when typical public transport assignment or simulation models would be used for real-world public transport networks. To improve transferability of our study results, we cluster stations based on their contribution to network vulnerability using unsupervised learning. This supports public transport agencies to apply the appropriate type of measure aimed to reduce disruptions or to mitigate disruption impacts for each station type. Applied to the Washington metro network, we predict a yearly passenger delay of 5.9 million hours for the total metro network. Based on the clustering, five different types of station are distinguished. Stations with high train frequencies and high passenger volumes located at central trunk sections of the network show to be most critical, along with start/terminal and transfer stations. Intermediate stations located at branches of a line are least critical., Transport and Planning

Transport infrastructure owners are moving from reactive toward proactive infrastructure management. This involves computation of costs associated with failure or maintenance, including expected transport delays. These delays are often computed by multiplying additional travel time by the number of travellers. However, this does not reflect the process of decision-making by travellers using the infrastructure asset, such as mode choices, departure time changes and trip cancellations to reduce time wasted in a traffic jam. Therefore, we introduce a multi-modal transport model that simulates travellers’ behaviour after a large-scale infrastructure failure at a critical node in the European TEN-T network. We use a novel approach of modelling the region around the infrastructure disruption in a very detailed manner, whereas the rest of Europe is modelled in a more basic way. This enables us to model impacts of disruptions in high detail, whereas also effects throughout Europe are considered, within reasonable computation time., Transport and Planning

The resilience of the Air Traffic Management (ATM) system to disturbances is required to maintain high operation performance. Before it can be improved, the resilience of the ATM system must be quantified. The measurement of resilience requires knowledge of a system reference state. This thesis proposes a novel methodology to detect disruptions without a pre-specified reference state and to quantify airspace resilience to disturbances. The method utilises residual-based anomaly detection to model a reference state based on historical values and detect deviations from it. The method has been tested in assessing the resilience of arrival time (airspace state)to high winds (disturbance) in 9 airports worldwide for a year. The results have shown that the method is capable of detecting disruptions as well as airports experiencing high wind conditions tend to be more resilient to them., Aerospace Engineering

Shrimp farming in Ecuador has become the main commercial activity for non-oil products, and its impact on the balance of trade dethroned the banana that for several years had been the biggest generator of wealth. The shrimp sector is prone to be affected by at least nine types of problems identified under the concept of disruptions, and the impact of these events has different degrees of affectation. The concept of resilience, which has its bases in psychology and physics, is used to apply it to the field of business management, in order to determine how the sector has responded to the disruptive events of the last decade, diagnosing its current situation and the evolution of the sector during the period 2010-2019. The present study is an exploratory research of qualitative character; it makes use of the documentary analysis taking official information of State organizations, articles of scientific magazines, articles of the local press and studies of academic repositories, and the focus group conformed by producers, distributors, exporters and workers of shrimp packing plants of the province of El Oro. The shrimp sector has grown considerably in the last ten years, and the decision making and commitment of the authorities and agencies that make up the sector is outstanding. There are still problems that represent discomfort mainly for producers, but they do not have a high impact on their performance. Considering the basis of the work done, the future for shrimp farming in Ecuador is encouraging., El cultivo de camarón en Ecuador se ha convertido en la principal actividad comercial de los productos no petroleros, y su impacto en la balanza comercial destronó al banano que por varios años había sido el mayor generador de riquezas. El sector camaronero es propenso a ser afectado por al menos nueve tipos de problemas identificados bajo el concepto de disrupciones, y el impacto de estos eventos tiene distintos grados de afectación. Se hace uso del concepto de resiliencia, que tiene sus bases en la psicología y la física, para aplicado al campo de la gestión empresarial permita determinar cómo ha respondido el sector ante los eventos disruptivos de la última década, diagnosticando su situación actual y la evolución sectorial que ha alcanzado en el período 2010 – 2019. El presente estudio es una investigación exploratoria de carácter cualitativo; se hace uso del análisis documental tomando información oficial de organismos del Estado, artículos de revistas científicas, artículos de la prensa local y estudios de repositorios académicos, y el focus group conformado por productores, distribuidores, exportadores y trabajadores de empacadoras de camarón de la provincia de El Oro. El sector camaronero ha crecido notablemente en los últimos diez años, se destaca la toma de decisiones y el alto compromiso que tienen las autoridades y agentes que lo conforman; aún existen problemas que representan malestar principalmente en los productores, pero no tienen una alta incidencia en su rendimiento. Considerando las bases del trabajo realizado, el futuro para la camaronicultura en Ecuador es alentador.

Shrimp farming in Ecuador has become the main commercial activity for non-oil products, and its impact on the balance of trade dethroned the banana that for several years had been the biggest generator of wealth. The shrimp sector is prone to be affected by at least nine types of problems identified under the concept of disruptions, and the impact of these events has different degrees of affectation. The concept of resilience, which has its bases in psychology and physics, is used to apply it to the field of business management, in order to determine how the sector has responded to the disruptive events of the last decade, diagnosing its current situation and the evolution of the sector during the period 2010-2019. The present study is an exploratory research of qualitative character; it makes use of the documentary analysis taking official information of State organizations, articles of scientific magazines, articles of the local press and studies of academic repositories, and the focus group conformed by producers, distributors, exporters and workers of shrimp packing plants of the province of El Oro. The shrimp sector has grown considerably in the last ten years, and the decision making and commitment of the authorities and agencies that make up the sector is outstanding. There are still problems that represent discomfort mainly for producers, but they do not have a high impact on their performance. Considering the basis of the work done, the future for shrimp farming in Ecuador is encouraging., El cultivo de camarón en Ecuador se ha convertido en la principal actividad comercial de los productos no petroleros, y su impacto en la balanza comercial destronó al banano que por varios años había sido el mayor generador de riquezas. El sector camaronero es propenso a ser afectado por al menos nueve tipos de problemas identificados bajo el concepto de disrupciones, y el impacto de estos eventos tiene distintos grados de afectación. Se hace uso del concepto de resiliencia, que tiene sus bases en la psicología y la física, para aplicado al campo de la gestión empresarial permita determinar cómo ha respondido el sector ante los eventos disruptivos de la última década, diagnosticando su situación actual y la evolución sectorial que ha alcanzado en el período 2010 – 2019. El presente estudio es una investigación exploratoria de carácter cualitativo; se hace uso del análisis documental tomando información oficial de organismos del Estado, artículos de revistas científicas, artículos de la prensa local y estudios de repositorios académicos, y el focus group conformado por productores, distribuidores, exportadores y trabajadores de empacadoras de camarón de la provincia de El Oro. El sector camaronero ha crecido notablemente en los últimos diez años, se destaca la toma de decisiones y el alto compromiso que tienen las autoridades y agentes que lo conforman; aún existen problemas que representan malestar principalmente en los productores, pero no tienen una alta incidencia en su rendimiento. Considerando las bases del trabajo realizado, el futuro para la camaronicultura en Ecuador es alentador.

Ports are located in low-lying coastal and riverine areas making them prone to the physical impacts of natural disasters. The consequential disruptions can potentially propagate through supply chains, resulting in widespread economic losses. Previous studies to quantify the risks of port disruptions have adopted various modelling assumptions about the resilience of individual ports and marine network logistics. However, limited empirical evidence is available to validate these modelling assumptions or to provide deeper understanding of the ways in which operations are adapted during and after disruptions. Here, we use vessel tracking data to analyse past port disruptions due to natural disasters, evaluating 141 incidences of disruptions across 74 ports and 27 disasters. Results show a median disruption duration of six days with a 95th percentile of 22.2 days. All analysed events show multiple ports being affected simultaneously, challenging some of the studies that only focus on single port disruptions. Moreover, we find that the duration of the disruption scales with the severity of the event, with an increment of 1.0 m storm surge or 10 m/s wind speed associated with a two day increase in disruption duration. In contrast to commonplace assumptions in model studies, substitution between ports is rarely observed during short-term disruptions. On the other hand, production recapture happens in practice in many cases of port disruptions. In short, empirical vessel tracking data provides valuable insights for future modelling studies in order to better approximate the extent of the disruption and the potential resilience of the port and maritime network.

Disruptions in public transport can have major implications for passengers and service providers. Our study objective is to develop a generic approach to predict how often different disruption types occur at different stations of a public transport network, and to predict the impact related to these disruptions as measured in terms of passenger delays. We propose a supervised learning approach to perform these predictions, as this allows for predictions for individual stations for each time period, without the requirement of having sufficient empirical disruption observations available for each location and time period. This approach also enables a fast prediction of disruption impacts for a large number of disruption instances, hence addressing the computational challenges that rise when typical public transport assignment or simulation models would be used for real-world public transport networks. To improve transferability of our study results, we cluster stations based on their contribution to network vulnerability using unsupervised learning. This supports public transport agencies to apply the appropriate type of measure aimed to reduce disruptions or to mitigate disruption impacts for each station type. Applied to the Washington metro network, we predict a yearly passenger delay of 5.9 million hours for the total metro network. Based on the clustering, five different types of station are distinguished. Stations with high train frequencies and high passenger volumes located at central trunk sections of the network show to be most critical, along with start/terminal and transfer stations. Intermediate stations located at branches of a line are least critical., Transport and Planning

In large-scale urban agglomerations, heavy rail in the form of metro and commuter train serves as the backbone of the metropolitan public transport network. The objective of this paper is to investigate whether networks with strikingly different structure and development pattern exhibit different robustness properties in the event of random and targeted attacks. We adopt a complex network theory approach, investigating network performances under alternative sequential disruption scenarios corresponding to the successive closure of either stations or track segments. We also investigate the case where the removal of a network node or link implies the closure of all traversing lines Network performance is measured both in terms of the capacity of the network to function in terms of connectivity as well as the additional impedance induced for those that remain connected. An aggregate robustness indicator based on the integral of the deterioration of network performance is adopted. Three exemplary networks are selected, the urban rail networks of London, Shanghai and Randstad. These three networks offer showcases of short and long development patterns, mono- and polycentric agglomeration structures, including the largest and the oldest metropolitan heavy rail networks. The polycentric network of the Randstad was found the least robust in this analysis when compared to the more monocentric networks of London and Shanghai. The London network is in general more robust than the Shanghai network thanks to the presence of cycles beyond the core. Our findings provide more nuanced evidence on the relation between network structure and development pattern, and its robustness., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Transport and Planning

Transport infrastructure owners are moving from reactive toward proactive infrastructure management. This involves computation of costs associated with failure or maintenance, including expected transport delays. These delays are often computed by multiplying additional travel time by the number of travellers. However, this does not reflect the process of decision-making by travellers using the infrastructure asset, such as mode choices, departure time changes and trip cancellations to reduce time wasted in a traffic jam. Therefore, we introduce a multi-modal transport model that simulates travellers’ behaviour after a large-scale infrastructure failure at a critical node in the European TEN-T network. We use a novel approach of modelling the region around the infrastructure disruption in a very detailed manner, whereas the rest of Europe is modelled in a more basic way. This enables us to model impacts of disruptions in high detail, whereas also effects throughout Europe are considered, within reasonable computation time., Transport and Planning