This research develops a novel cross-disciplinary framework that bridges financial systemic risk modeling with supply chain network analysis to advance resilience assessment and policy guidance.The approach integrates...This research develops a novel cross-disciplinary framework that bridges financial systemic risk modeling with supply chain network analysis to advance resilience assessment and policy guidance.The approach integrates established financial contagion frameworks with the topology of the supply chain network,introducing the concept of“too central to fail”suppliers through systematic importance scoring methodologies.The framework reveals striking asymmetries in supply chain vulnerability patterns.While the majority of suppliers demonstrate systemic importance within network structures,financial fragility analysis indicates remarkable overall network robustness,with minimal nodes exhibiting high vulnerability thresholds.Most significantly,comprehensive stress testing exposes a critical paradox:networks demonstrate moderate resilience to random disruptions yet remain substantially vulnerable to strategic targeting of central nodes.Cascade failure analysis through multiple simulation approaches unveils the dual nature of supply chain risk propagation.Random shock scenarios generate manageable failure rates,while targeted attacks on high-centrality suppliers achieve disproportionate network impact.Most alarmingly,liquidity crisis simulations demonstrate how financial contagion mechanisms can affect nearly half of all network participants,highlighting the interconnected nature of operational and financial vulnerabilities.These findings establish quantitative foundations for the assessment of systemic risk in supply chains,with immediate implications for regulatory frameworks,early warning systems,and resilience enhancement strategies.The integrated financial-operational risk framework advances the theoretical understanding of the propagation of cross-sector vulnerability while providing systematic methodologies for identifying critical suppliers whose failure could trigger systemic collapse.展开更多
The constraints of transportation networks are fundamental to disaster planning.Having the capability of evaluating the emergent dynamics of such networks in the context of large traffic incidents can inform the desig...The constraints of transportation networks are fundamental to disaster planning.Having the capability of evaluating the emergent dynamics of such networks in the context of large traffic incidents can inform the design of traffic management strategies.On February 7,2019,the Richmond-San Rafael Bridge in the San Francisco Bay Area,connecting multiple cities and carrying over 100000 vehicles daily,had to be suddenly closed for over 9 hours due to a structural failure of its upper deck.This incident caused major disruptions in the region as the typical traffic was interrupted and detoured as travelers found alternate routes.In this study,we demonstrate the capability of large-scale traffic impact assess-ments of major network disruptions using the Richmond-San Rafael Bridge closure as a case study.Using a high-performance,parallel-discrete event traffic simulation,we assess the traffic impacts resulting from the bridge closure at both the regional system and city levels.Our model estimates that the region incurred an additional 14000 vehicle hours of delay and 600000 vehicle miles in distance due to the bridge closure.The incident affected over 55000 trips;certain trips experienced an increase of 46 min in delay and 26 miles in travel distance.The median traffic volume on neighborhood streets in San Francisco,Vallejo,and San Rafael increased by 30%,22%,and 13%,respectively.The results suggest that the cities’local roads provided the additional adaptive capacity to disperse the traffic.With large-scale modeling of a critical network disruption using dynamic rerouting capability,complete road network,and full demand,we provide valuable insights into the response dynamics of this specific event.In doing so,the value of such regional analyses to incident and disaster planning is demonstrated.展开更多
The Alps are highly impacted by debris flows that cause major problems for companies and transport networks located in the valley bottoms. One such event occurred in the Rif Blanc catchment and affected the road netwo...The Alps are highly impacted by debris flows that cause major problems for companies and transport networks located in the valley bottoms. One such event occurred in the Rif Blanc catchment and affected the road network in the French Alps, as well as adjacent areas across the Italian border, for several days in June 2012. This article presents two independent approaches to vulnerability assessment. Based on investigations conducted during a survey of local authorities following the event, we compared theoretical risk management and real crisis management in terms of decision making and modes of intervention. Functional vulnerability and territorial consequences were analyzed using a best travel time model of accessibility. We show that a bottom-up approach is practiced in case of actual management planning with a central coordination of general council. Conversely theoretical crisis management shows prefect as the key actor supported by several other state institutions. Our analysis also revealed that a debris flow event with a local impact on the road network has territorial consequences at a regional scale. This study contributes to the discussion about how to minimize the vulnerability of alpine transport networks prone to debris flows. Our results could serve as a decision support tool for public authorities.展开更多
文摘This research develops a novel cross-disciplinary framework that bridges financial systemic risk modeling with supply chain network analysis to advance resilience assessment and policy guidance.The approach integrates established financial contagion frameworks with the topology of the supply chain network,introducing the concept of“too central to fail”suppliers through systematic importance scoring methodologies.The framework reveals striking asymmetries in supply chain vulnerability patterns.While the majority of suppliers demonstrate systemic importance within network structures,financial fragility analysis indicates remarkable overall network robustness,with minimal nodes exhibiting high vulnerability thresholds.Most significantly,comprehensive stress testing exposes a critical paradox:networks demonstrate moderate resilience to random disruptions yet remain substantially vulnerable to strategic targeting of central nodes.Cascade failure analysis through multiple simulation approaches unveils the dual nature of supply chain risk propagation.Random shock scenarios generate manageable failure rates,while targeted attacks on high-centrality suppliers achieve disproportionate network impact.Most alarmingly,liquidity crisis simulations demonstrate how financial contagion mechanisms can affect nearly half of all network participants,highlighting the interconnected nature of operational and financial vulnerabilities.These findings establish quantitative foundations for the assessment of systemic risk in supply chains,with immediate implications for regulatory frameworks,early warning systems,and resilience enhancement strategies.The integrated financial-operational risk framework advances the theoretical understanding of the propagation of cross-sector vulnerability while providing systematic methodologies for identifying critical suppliers whose failure could trigger systemic collapse.
基金supported by the U.S.Department of Energy(DOE)Vehicle Technologies Office(VTO)under the Big Data Solutions for Mobility Program,an initiative of the Energy Efficient Mobility Systems(EEMS)Program.The research used resources of the National Energy Research Scientific Computing Center,a DOE Office of Science User Facility supported by the Office of Science of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231.
文摘The constraints of transportation networks are fundamental to disaster planning.Having the capability of evaluating the emergent dynamics of such networks in the context of large traffic incidents can inform the design of traffic management strategies.On February 7,2019,the Richmond-San Rafael Bridge in the San Francisco Bay Area,connecting multiple cities and carrying over 100000 vehicles daily,had to be suddenly closed for over 9 hours due to a structural failure of its upper deck.This incident caused major disruptions in the region as the typical traffic was interrupted and detoured as travelers found alternate routes.In this study,we demonstrate the capability of large-scale traffic impact assess-ments of major network disruptions using the Richmond-San Rafael Bridge closure as a case study.Using a high-performance,parallel-discrete event traffic simulation,we assess the traffic impacts resulting from the bridge closure at both the regional system and city levels.Our model estimates that the region incurred an additional 14000 vehicle hours of delay and 600000 vehicle miles in distance due to the bridge closure.The incident affected over 55000 trips;certain trips experienced an increase of 46 min in delay and 26 miles in travel distance.The median traffic volume on neighborhood streets in San Francisco,Vallejo,and San Rafael increased by 30%,22%,and 13%,respectively.The results suggest that the cities’local roads provided the additional adaptive capacity to disperse the traffic.With large-scale modeling of a critical network disruption using dynamic rerouting capability,complete road network,and full demand,we provide valuable insights into the response dynamics of this specific event.In doing so,the value of such regional analyses to incident and disaster planning is demonstrated.
基金supported by the project Eranet Circle-Mountain Arnica ‘‘Assessment of Risks on transportation Networks resulting from slope Instability and Climate change in the Alps’’
文摘The Alps are highly impacted by debris flows that cause major problems for companies and transport networks located in the valley bottoms. One such event occurred in the Rif Blanc catchment and affected the road network in the French Alps, as well as adjacent areas across the Italian border, for several days in June 2012. This article presents two independent approaches to vulnerability assessment. Based on investigations conducted during a survey of local authorities following the event, we compared theoretical risk management and real crisis management in terms of decision making and modes of intervention. Functional vulnerability and territorial consequences were analyzed using a best travel time model of accessibility. We show that a bottom-up approach is practiced in case of actual management planning with a central coordination of general council. Conversely theoretical crisis management shows prefect as the key actor supported by several other state institutions. Our analysis also revealed that a debris flow event with a local impact on the road network has territorial consequences at a regional scale. This study contributes to the discussion about how to minimize the vulnerability of alpine transport networks prone to debris flows. Our results could serve as a decision support tool for public authorities.
