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Electric Vehicle Demand-Responsive Transport with Transit Integration
Full text linkIntegrated Demand-Responsive Transport (IDRT), which combines demand-responsive transport services with regular transit systems, is widely recognized as an effective strategy to mitigate the impact of standalone demand-responsive services on traffic congestion and the environment. However, successful implementation of such service must address customer inconvenience, as transfers between demand-responsive vehicles and transit services often discourage ridership. As the transition towards sustainable mobility accelerates, it is essential to incorporate electric vehicles into IDRT to enhance environmental benefits. Involving electric vehicles in the IDRT system also brings additional challenges, particularly in managing charging operations and ensuring service reliability. This dissertation introduces an Electric Integrated Demand-responsive Transport (EIDRT) service, in which electric buses operates with fixed-route transit to effectively meet customer demand.
To address the complexity of the EIDRT problem, we first investigate a meeting-point-based first mile feeder service utilizing electric buses. The objective is to minimize bus operational costs and customer inconvenience, including reducing customers’ waiting time at transit stations. Bus charging operations consider capacitated charging stations. A Mixed-Integer Linear Programming (MILP) formulation is developed using a layered graph structure and a metaheuristic solution algorithm is proposed. Computational experiments demonstrate that the metaheuristic produces good-quality solutions with around 1 or 2 minutes to solve 100-customer test instances. Results also show that the layered-graph significantly reduces computational time.
Next, we extend the meeting-point-based first-mile feeder service to a many-to-many EIDRT service that connects customers from their origins to destinations. A MILP formulation is proposed with the objective function minimizing both bus operational costs and customer travel times. To reduce customer inconvenience, the service incorporates synchronization between demand-responsive buses and transit departures, along with a maximum inter-modal transfer time. Capacitated charging stations are also included to reflect realistic recharging operations. The MILP formulation is built on a departure-expanded transit graph, incorporating the layered graph concept to better represent the transit network within a service area. A hybrid large neighborhood search algorithm is proposed to efficiently solve the problem, addressing the challenges of multi-modal routing and capacitated charging stations. The algorithm is benchmarked against eight-hour solutions by a MILP solver, demonstrating efficiency and better solution quality for up to 100 customers with two transit lines.
Lastly, the performance of the EIDRT is assessed by a set of experiments on scenarios reflecting real-world problem size and a case study. The findings provide valuable insights for operators regarding the trade-offs between operational costs and customer convenience, particularly focus on fleet size, buses’ state-of-charge, and transit networks. Results indicate that while the EIDRT service saves vehicle kilometers traveled compared with non-integrated demand-responsive services, maintaining a high-quality service might still require the same or a larger bus fleet size. Moreover, the results show that the service performs the best when the transit network in the service area is well-connected. The case study further compares the EIDRT service with existing transportation options, confirming significant reductions in bus operating costs relative to non-integrated demand-responsive services. Similar results are found that bus travelling costs are saved significantly compared to non-integrated demand-responsive services. In terms of customer travel experiences, EIDRT achieves substantially lower customer travel times compared to traditional public transport.9. Industry, innovation and infrastructure11. Sustainable cities and communitie
Biodiversity loss and entrepreneurship: Empirical evidence on threat perceptions among primary-sector entrepreneurs in 28 European countries
No full textpeer reviewedBiodiversity loss is widespread and accelerating, threatening ecological systems and human well-being. Entrepreneurship and biodiversity loss are intertwined: entrepreneurs—especially in the primary sector—are both causing and suffering from this loss in biodiversity. However, little is known about the biodiversity-entrepreneurship nexus, in particular, how primary sector entrepreneurs perceive the negative effects of their activities on nature and biodiversity loss. Addressing this glaring and policy-relevant research gap, we empirically investigate how 3,469 entrepreneurs across 28 European countries perceive threats to biodiversity. Despite their close dependence on nature, our multilevel analyses show that primary sector entrepreneurs perceive activities related to the primary sector (e.g., intensive farming, intensive forestry, and overfishing) as less threatening to biodiversity loss than entrepreneurs in other sectors. However, this difference diminishes in countries with stronger reliance on the primary sector, suggesting a nuanced interplay between economic dependencies and biodiversity threat perception. Our study contributes to research on biodiversity and entrepreneurship, identifies crucial future research areas, and offers policy implications that can help societies leverage biodiversity entrepreneurs, and entrepreneurship more generally, as a vehicle to combat biodiversity loss.14. Life below water15. Life on land8. Decent work and economic growt
Congruence theorems for triangles and convex quadrilaterals involving heights
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Gathering Electronic Evidence in the Digital Era: A Jigsaw Puzzle of Technological and Legal Challenges
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Kummer theory for function fields
Full text linkpeer reviewedWe develop Kummer theory for algebraic function fields in finitely many transcendental variables. We consider any finitely generated Kummer extension (possibly, over a cyclotomic extension) of an algebraic function field, and describe the structure of its Galois group. Our results show in a precise sense how the questions of computing the degrees of these extensions and of computing the group structures of their Galois groups reduce to the corresponding questions for the Kummer extensions of their constant fields.Studies In The Explicit And The Statistical Aspects Of Modular Forms And Elliptic Curve
Review of Victor Grandaubert, L’immunité d’exécution de l’Etat étranger et des organisations internationales en droit international, Pedone, 2023
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Enhancing Regional NWP Model with GNSS Zenith Total Delay Assimilation: A WRF and WRFDA 3D-Var Approach in the Greater Region of Luxembourg
No full textAI Risk Assessments in EU Large-Scale IT Systems for Third-country Nationals and Access to Remedies: A Bumpy Road Ahead
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Memory function and early exit from paid employment through different pathways among ageing European workers.
Full text linkpeer reviewed[en] OBJECTIVES: Understanding memory function's role in early workforce exit is key in supporting sustainable employment among ageing workers. This study examined the impact of memory function on early exit from paid employment, analyzed changes in memory function before, during and after such transitions, and assessed memory function trajectories in relation to the presence or absence of effort-reward imbalance at work.
METHODS: This study included 16 339 respondents from the Survey of Health, Ageing, and Retirement in Europe (SHARE) between age 50 and the country-specific retirement age. The effects of objective and subjective memory functioning on early exit were assessed using Cox proportional hazards with Fine-Gray sub distribution models. Changes in memory function before and after a transition to non-employment were assessed using generalized linear mixed-effects models. These changes were described and compared based on exposure to job effort-reward imbalance.
RESULTS: Workers with poor subjective memory were 2.3 times more likely to exit employment prematurely due to disability ([sub-distribution hazard ratio (SHR) 2.30, 95% confidence interval (CI) 1.77-3.00] and 1.3 times more likely to exit through unemployment (SHR 1.29, 95% CI 1.06-1.55). Workers with low objective memory were 1.6 times more likely to exit through unemployment (SHR 1.56, 95% CI 1.30-1.87). Subjective memory generally declined prior to, and during early exit from paid employment. While subjective memory generally improved post-exit, objective memory function declined after exiting. An accelerated decline in objective memory functioning was noted among early retirees who had been exposed to effort-reward imbalance at work (β -0.45, standard error 0.16).
CONCLUSION: Workers with poor memory function are at higher risk of early involuntary exit from paid employment. Promoting memory function and balancing job efforts and rewards may help mitigate the risk of a premature exit.3. Good health and well-bein