摘要
Abstract
To enhance the interconnectivity between the transportation scheme and the time-varying container flow demand,this paper optimized the transportation scheme of high speed railway express considering the container flow transit scenario by leveraging the piggyback transportation mode of existing passenger-carrying trains.In view of the dual dependence of the container flow transportation scheme on the occupation of train time and space resources,a time-space network consisting of four types of nodes and five types of arc segments was constructed,with the train and express container serving as the research objects.On this basis,this paper formulated a time-space network optimization model for the transportation scheme,with the objective of minimizing the total delivery time of express containers.Furthermore,the constraints of train loading capacity,container flow boarding,transit,and conservation were considered.According to the model characteristics,the paper designed a Lagrangian relaxation algorithm to solve the problem.By decomposing the original problem into a subproblem of determining the shortest transportation path of a single express container,the paper developed an upper-bound feasibility algorithm that focused on eliminating the conflict of violating the train capacity constraints.Lastly,the paper utilized the Xi'an-Lanzhou High Speed Railway as a case study for verification,and the results indicate that the proposed model and algorithm can rapidly generate an acceptable solution,effectively increasing the full load factor of the trains.Moreover,compared with the case of direct transportation,container flow transit can effectively address the congestion issue of express containers.关键词
高铁快运/运输方案/箱流中转/时空网络/拉格朗日松弛Key words
High Speed Railway Express/Transportation Scheme/Container Flow Transit/Time-Space Network/Lagrangian Relaxation Algorithm分类
交通运输
