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Supplier selection based on multi-stakeholder Best- Worst Method
Get PDFSupplier selection and supplier segmentation are two interdependent crucial steps of effective supplier relationship management. Supplier selection is formulated as a multi-criteria decision-making problem, in which evaluation criteria play a critical role in a realistic assessment of the suppliers. The evaluation criteria can be used to link supplier selection and segmentation steps to have a more efficient and effective supplier relationship management. A multi-stakeholder Best-Worst Method (BWM) is used for supplier selection. The proposed method is a proper tool to handle the optimal weights of the BWM, which are in the form of intervals. The proposed approach enables decision-makers to avoid information loss within their decision-making procedure resulting in more realistic decisions. A real-world case study is used to illustrate the proposed decision-making framework. The final results show the best suppliers based on both capabilities and willingness dimensions which can be selected by the case company
‘What are people for?’: Ecologists and the Articulation of the Built Environment
Get PDFThis article revisits previously overlooked exchanges between pre-eminent figures in British architecture and ecology, William Holford, Julian Huxley, and Max Nicholson, which were incorporated in one of the earliest uses of the term ‘built environment’ in 1964. By examining how an energy-entropy interpretation of the ecosystem had shaped their views on the natural, human-made, and psychosocial milieu, I will consider the way cybernetics conditioned the articulation of the built environment. Contextualising their exchanges in the socio-cultural climate of the early 1960s, I trace an almost concurrent environmental turn made by architecture and ecology. Moreover, the exchange between architecture and ecology has engendered an environmental conception that prioritised the transformative and reciprocal relationship between humans and what surrounds them. In this effort, I pay particular attention to a co-evolutionary view of the technosphere, biosphere, and political sphere formulated by Nicholson. I also discuss the infiltration of eugenic and technocratic views in this reconceptualisation of the environment. Despite the peculiarities of these theories, their conceptualisation of the environment had pointed towards an important question in employing the ecosystemic metaphor: what are people for
What is really uncovered by mixing different model structures: contrasts between latent class and model averaging
Get PDFLatent class models have long been a tool for capturing heterogeneity across decisionmakers in the sensitivities to individual attributes. More recently, there has been increased interest in using these models to capture heterogeneity in actual behavioural processes, such as information/attribute processing and decision rules. This often leads to substantial improvement in model fit and the apparent finding of large clusters of individuals making choices in ways that are substantially different from those used by others. Such findings have however not been without criticism given the potential risk of confounding with other more modelspecific heterogeneity. In this paper, we consider an alternative approach for exploring the issue by contrasting the findings obtained with model averaging, which combines the results from a number of separately (rather than simultaneously) estimated models. We demonstrate that model averaging can accurately recover the different data generation processes used to create a number of simulated datasets and thus beused to infer likely sources of heterogeneity. We then use this new diagnostic tool on two stated choice case studies. For the first, we find that the use of model averaging leads to significant reductions in the amount of heterogeneity of the type analysts have sought to uncover with latent class structures of late. For the second, results from model averaging show clear evidence of the existence of both taste and decision rule heterogeneity. Overall, however, our results suggest that heterogeneity in the sensitivities to individual attributes rather than the behavioural process per se could be the key factor behind the improvements gained through the adoption of latent class models for heterogeneity in behavioural processes
A vulnerability analysis of rail network disruptions during winter weather in the Netherlands
Get PDFThis paper presents a rail network vulnerability analysis to identify which links within the Dutch rail network are most vulnerable to winter weather. A vulnerability index was developed to measure rail vulnerability during winter weather based on switch-related disruptions, integrating both node and link components into a probabilistic measure of vulnerability. The analysis looked at disruption data for 379 Dutch stations during the years 2007-2017. Links in dense population areas, which operate a high number of switches, are most susceptible to winter disturbances. Particularly, three main railway stations (Utrecht, Amersfoort and Zwolle) are the most critical locations within the network in terms of extreme winter conditions and disruptions. In addition, we developed two scenarios to analyse implications of different railway switch reduction strategies on rail vulnerability. The proposed rail vulnerability index can be a useful tool to define operational strategies to reduce the vulnerability of the Dutch railway network. Decreasing the number of switches at station areas appears to be more effective for reducing railway vulnerability than decreasing the number of switches throughout the entire network
Impact of COVID-19 lockdown on commuting: A multi-country perspective
Get PDFWe carried out an international online survey about changes in everyday mobility during the COVID-19 outbreak in 21 languages, collecting more than 11,000 responses from more than 100 countries. In this paper, we present our analysis about commuting travels of the responses between 23 March and 12 May 2020 from the fourteen countries with 100 or more responses, namely Austria, Brazil, Bulgaria, Czechia, Germany, Hungary, Iran, Italy, Japan, Malaysia, Slovakia, Slovenia, Thailand, and the UK. Home office is used typically by between 40% and 60% of working respondents. Among people with workplaces with possibility for home office, the percentage is between 60% and 80%. Among people with workplaces where presence is essential, the percentage does not typically go beyond 30%. This result potentially implies an ultimate magnitude of a strong home office measure. Among those who continued to commute but switched commuting transport modes from public transport to others, the COVID-19 infection risk in public transport is the reason that is most often referred to, but many of those who changed to private cars and to bicycles report reduced travel time, too. Measures to encourage the use of active travel modes where possible are strongly recommended, as this would potentially mitigate undesirable modal shift towards private motorized modes triggered by perception of infection risks while travelling with public transport
The acceptance of conditionally automated cars from the perspective of different road user groups
Get PDFThe foreseeable advent of conditionally automated cars (CACs) at SAE Level 3 opens a range of opportunities along with numerous questions that must be addressed to safely adopt this new vehicle technology. While public acceptance and the acceptance of potential users have already been intensively researched, this study investigates the acceptance of CACs from the point of view of different road user groups, such as pedestrians, cyclists and riders of powered two-wheelers (PTWs) as so-called vulnerable road users (VRUs), as well as the drivers of conventional cars. The study measures a priori road user acceptance of CACs using an international population survey that was conducted within the framework of the EU-funded project ‘BRidging gaps for the adoption of Automated Vehicles’ (BRAVE) in the participating countries France, Germany, Slovenia, Spain and Sweden as well as in Australia and the USA. Including 5,827 respondents, the study findings disclose a rather positive acceptance of CACs from the perspective of different road user groups. However, concerns are also apparent. Results from multivariate analyses indicate that the acceptance of CACs differs between road user groups in that VRUs demonstrated lower acceptance than non-automated car drivers. The role of trust in the new vehicle technology also appears to be remarkable. Consequently, future developments of CACs should also focus on communication between automated cars and bystanders (e.g. via external human-machine interfaces) to reduce uncertainties and promote trust
Tracing the Effects of the Covid-19 Pandemic on Car Usage in Germany - an Analysis of the German Mobility Panel
Get PDFBeing a vast external influence, the COVID-19 pandemic causes major changes in travel behavior on the individual level. This exceptional situation and the political measures such as the lockdown lead to decreased overall travel demand and shifts in mode choice. To understand these effects, the analysis of car usage in private households offers explanatory insights. To this aim, this study provides a differentiation of car usage before and during the COVID -19 pandemic in spring 2020. Furthermore, insights into structural changes of car usage in private households based on German Mobility Panel data are presented. The results show that during the COVID -19 pandemic car usage was affected, and overall mileage decreased. Especially newer cars with large cubic capacity show a large decrease in mileage by 39 % between 2019 and 2020. In addition, we see that the type of car usage (business/private) and the household characteristics are related to different magnitudes of change in car usage. Overall, it becomes evident that examining identical households and cars before and during the pandemic allows for a deeper understanding of the impacts of the COVID -19 pandemic
Curbing cost overruns in infrastructure investment: Has reference class forecasting delivered its promised success?
Get PDFInfrastructure projects around the world have long been notorious for exceeding their budgets. To address persistent cost overruns, the American Planning Association urged planners to adopt reference class forecasting alongside traditional methods but the practice has not caught on in the U.S. Conversely, the U.K. adopted Kahneman’s Nobel Prize-winning theory to challenge biases in human judgment and mandated reference class forecasting for major projects in 2003. Has reference class forecasting, originally developed to rectify honest mistakes, brought the promised success in the public sector wherein political pressure is significant? Through before-and-after and with-and-without comparisons of 107 major projects, this empirical study examines the practical relevance of reference class forecasting for infrastructure investments. A before-and-after comparison reveals that the average cost overrun declined from 38% to 5% following the introduction of reference class forecasting. A with-and-without comparison also demonstrates that the U.K. surpassed its targeted probability of completing projects within budget by 12% using reference class forecasting, whereas the U.S. underperformed by 17%. Thus, reference class forecasting has engendered notable improvements in estimation in the U.K. This empirical study demonstrates the benefits of supplementing or replacing the current forecasting method. The findings can be used to reduce substantial financial risks for the government as well as social and economic welfare losses for society
Spatial water calendar: An illustrative workbook for adaptive transformation
Get PDFIn this paper, concepts for deploying climate resilient design in deltaic regions which encounter environmental challenges are explored. Today, most deltas experience persistent flooding and long-term waterlogging which adversely affects the livelihood of its inhabitants. A new approach was formulated to rethink design and planning pedagogies in the discipline of landscape architecture at Delft University of Technology, to visualize open-ended spatial transformations involving both the landscape architect and the inhabitants over longer periods of time. The graduates proposed flexible spatial frameworks that integrate time and people1. This results in design interventions that do not rely on a fixed plan, but rather propose and visualize a process using a ‘water calendar’ as the driving force. The spatial water calendar is a chart that helps to represent time linked to space and water which can be useful to enumerate, elucidate, and determine time-based fluctuations in a landscape and make decisions accordingly. The idea was prompted by ancient calendars that were based on the rhythm of seasons – a method which farmers often used. However, the spatial water calendar also integrates other processes which are influenced by water, focussing specifically on the spatial impact, thereby becoming a design tool for landscape architects. The calendar developed in the Circular Water Stories lab is an open-ended framework stirred by a sequence of spatial drawings showing the temporal and social processes in relation to human-made interventions, resulting in spatial transformations through time and scale. Because working with a calendar is highly participatory in nature, the spatial water calendar will be more meaningful in vulnerable geographies2 where there is still a strong connection between people and landscape. Nevertheless, in other parts of the world, we imagine that this approach also opens new possibilities for landscape architects to engage with dynamic sites. 
Getting to ecosystem-based function: Exploring the power to influence Columbia River Treaty modernization towards ecosystem considerations
Get PDFGovernance of international rivers is shifting to include a diversity of actors below the nation state, and interests beyond those traditionally conceived to facilitate economic growth and security, such as hydropower and flood risk management. Consequently, the degree and mechanisms of influence and power of these new actors is of increasing interest in transboundary water governance scholarship, to understand whose voices are heard and whose interests are included in decision-making processes. We introduce a typology of power developed by Barnett and Duvall (2005) to illustrate the influence of Indigenous nations and local actors to position ecosystem-based function as a primary objective for modernization of the 1964 Columbia River Treaty (CRT) in the Pacific Northwest of North America. We identify four themes that emerged from the data analysis that explain the influence of Indigenous nations and local actors on CRT modernization: a shift in the legal landscape regarding Indigenous rights and title in resource management; an evolution in societal values regarding environmental issues; efforts of Indigenous nations and local actors to frame the issues for CRT modernization; and, engagement of Indigenous nations in transboundary collaboration for CRT modernization. The conclusion draws lessons for how these types of power can shape the course of traditionally state-centric transboundary water governance processes. 
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