We apply a flow-based location model,called Multipath Refueling Location Model(MPRLM),to develop an electric vehicle(BV)public charging infrastructure network for enabling long-haul inter-city EY trips.The model consi...We apply a flow-based location model,called Multipath Refueling Location Model(MPRLM),to develop an electric vehicle(BV)public charging infrastructure network for enabling long-haul inter-city EY trips.The model considers multiple deviation paths between every origin-destination(O-D)pairs and relaxes the commonly adopted assumption that travelers only take a shortest path between O-D pairs.This model is a mixed-integer linear program,which is intrinsically difficult to solve.With greedy-adding based heuristics,the MPRLM is applied to optimally deploy EV fast charging stations along major highway corridors in South Carolina.Compared to engineering methods,the optimization model reduces the capital cost of establishing a fast charging network by two thirds.We also explore the interplay between the spatial distributions of cities,vehicle range,and routing deviation tolerance as well as their impacts on the locational strategies.展开更多
Many older highway bridges in the United States(US)are inadequate for seismic loads and could be severely damaged or collapsed in a relatively small earthquake.According to the most recentAmerican Society of Civil Eng...Many older highway bridges in the United States(US)are inadequate for seismic loads and could be severely damaged or collapsed in a relatively small earthquake.According to the most recentAmerican Society of Civil Engineers’infrastructure report card,one-third of the bridges in the US are rated as structurally deficient and many of these structurally deficient bridges are located in seismic zones.To improve this situation,at-risk bridges must be identified and evaluated and effective retrofitting programs should be in place to reduce their seismic vulnerabilities.In this study,a new retrofit strategy decision scheme for highway bridges under seismic hazards is developed and seamlessly integrate the scenario-based seismic analysis of bridges and the traffic network into the proposed optimization modeling framework.A full spectrum of bridge retrofit strategies is considered based on explicit structural assessment for each seismic damage state.As an empirical case study,the proposed retrofit strategy decision scheme is utilized to evaluate the bridge network in one of the active seismic zones in the US,Charleston,South Carolina.The developed modeling framework,on average,will help increase network throughput traffic capacity by 45%with a cost increase of only$15million for the Mw 5.5 event and increase the capacity fourfold with a cost of only$32m for the Mw 7.0 event.展开更多
文摘We apply a flow-based location model,called Multipath Refueling Location Model(MPRLM),to develop an electric vehicle(BV)public charging infrastructure network for enabling long-haul inter-city EY trips.The model considers multiple deviation paths between every origin-destination(O-D)pairs and relaxes the commonly adopted assumption that travelers only take a shortest path between O-D pairs.This model is a mixed-integer linear program,which is intrinsically difficult to solve.With greedy-adding based heuristics,the MPRLM is applied to optimally deploy EV fast charging stations along major highway corridors in South Carolina.Compared to engineering methods,the optimization model reduces the capital cost of establishing a fast charging network by two thirds.We also explore the interplay between the spatial distributions of cities,vehicle range,and routing deviation tolerance as well as their impacts on the locational strategies.
基金supported by the National Science Foundation,under Grant No.NSF-1011478.
文摘Many older highway bridges in the United States(US)are inadequate for seismic loads and could be severely damaged or collapsed in a relatively small earthquake.According to the most recentAmerican Society of Civil Engineers’infrastructure report card,one-third of the bridges in the US are rated as structurally deficient and many of these structurally deficient bridges are located in seismic zones.To improve this situation,at-risk bridges must be identified and evaluated and effective retrofitting programs should be in place to reduce their seismic vulnerabilities.In this study,a new retrofit strategy decision scheme for highway bridges under seismic hazards is developed and seamlessly integrate the scenario-based seismic analysis of bridges and the traffic network into the proposed optimization modeling framework.A full spectrum of bridge retrofit strategies is considered based on explicit structural assessment for each seismic damage state.As an empirical case study,the proposed retrofit strategy decision scheme is utilized to evaluate the bridge network in one of the active seismic zones in the US,Charleston,South Carolina.The developed modeling framework,on average,will help increase network throughput traffic capacity by 45%with a cost increase of only$15million for the Mw 5.5 event and increase the capacity fourfold with a cost of only$32m for the Mw 7.0 event.
