Bus electrification is widely cited as a key technique to reduce carbon emissions and mit-igate climate change.In some Chinese cities,the electrification rate of buses has even reached 100%.However,compared with diese...Bus electrification is widely cited as a key technique to reduce carbon emissions and mit-igate climate change.In some Chinese cities,the electrification rate of buses has even reached 100%.However,compared with diesel buses(DBs),electric buses(EBs)cause scheduling problems during urban flash floods due to their limited wading performance.This study proposes a mixed EB-DB fleet strategy to mitigate bus fleet problems during urban flash floods.The difference in wading height thresholds between EBs and DBs is con-sidered in the fleet schedule.Utilizing a two-fleet strategy,the requisite number of DBs for bus depots is calculated.The mixed bus assignment problem is then solved by linear pro-gramming to establish the optimal dispatch scheme for the individual bus route.This study emphasizes the advantages of mixed bus fleets in emergency response,and contributes to improving urban transportation resilience.展开更多
In order to facilitate the scientific management of large-sized shipping companies, fleet planning under complicated circumstances has been studied. Based on multiple influencing factors such as the techno-economic st...In order to facilitate the scientific management of large-sized shipping companies, fleet planning under complicated circumstances has been studied. Based on multiple influencing factors such as the techno-economic status of ships, the investment capacity of company, the possible purchase of new ships, the buying/selling of second-hand vessels and the chartering/renting of ships, a mixed-integer programming model for fleet planning has been established. A large-sized shipping company is utilized to make an empirical study, and Benders decomposition algorithm is employed to test the applicability of the proposed model. The result shows that the model is capable for multi-route, multi-ship and large-scaled fleet planning and thus helpful to support the decision making of large-sized shipping companies.展开更多
基金supported by the National Key R&D Program of China under Grant No.2023YFC3804004the Fundamental Research Funds for the Central Universities(Grant No.2022-5-YB-02).
文摘Bus electrification is widely cited as a key technique to reduce carbon emissions and mit-igate climate change.In some Chinese cities,the electrification rate of buses has even reached 100%.However,compared with diesel buses(DBs),electric buses(EBs)cause scheduling problems during urban flash floods due to their limited wading performance.This study proposes a mixed EB-DB fleet strategy to mitigate bus fleet problems during urban flash floods.The difference in wading height thresholds between EBs and DBs is con-sidered in the fleet schedule.Utilizing a two-fleet strategy,the requisite number of DBs for bus depots is calculated.The mixed bus assignment problem is then solved by linear pro-gramming to establish the optimal dispatch scheme for the individual bus route.This study emphasizes the advantages of mixed bus fleets in emergency response,and contributes to improving urban transportation resilience.
基金the Doctoral Programs Foundation ofMinistry of Education of China(No.20102125110002)
文摘In order to facilitate the scientific management of large-sized shipping companies, fleet planning under complicated circumstances has been studied. Based on multiple influencing factors such as the techno-economic status of ships, the investment capacity of company, the possible purchase of new ships, the buying/selling of second-hand vessels and the chartering/renting of ships, a mixed-integer programming model for fleet planning has been established. A large-sized shipping company is utilized to make an empirical study, and Benders decomposition algorithm is employed to test the applicability of the proposed model. The result shows that the model is capable for multi-route, multi-ship and large-scaled fleet planning and thus helpful to support the decision making of large-sized shipping companies.
