Research On Express Network Optimization Based On Multiple Transportation Modes

With the rapid development of China's e-commerce and express logistics industry,the application of multimodal transport has become the focus of the research field of express logistics.In the multimodal transport network or express delivery network,how to reduce costs and improve efficiency at the same time is particularly important.Based on the real logistics transportation network and hub-spoke express delivery network,this paper uses mathematical modeling and heuristic algorithm to optimize the transportation route and express delivery network structure of the real road network.This paper toke into account the constraints of multimodal transport,time window and volume constraints.The main works we did are as follows:(1)Based on the real physical flow transport network,this paper established a comprehensive optimization model for the mode and route selection of multimodal transport network.The optimization model takes into account such factors as transportation cost,transportation time,transshipment cost and transshipment time.This paper proposed an improved A*algorithm with time window to solve the optimization problem of real road network gridding multimodal transport network.The numerical example shows that the improved algorithm can obtain the best transportation route and mode at the same time.(2)Based on Hub-and-Spoke express network,this paper established a comprehensive optimization model of network node allocation and transportation path for express delivery based on multimodal transport.The model considers transportation cost,sorting cost,transportation time,transit cost,waiting time and other factors.Based on this model,this paper proposed an optimization algorithm for express delivery network based on simulated annealing algorithm.This paper analyzed the efficiency and results of the algorithm under the given hub set and the given hub set respectively.(3)Based on the second part,this paper used theory of division of labor in new classical economics and Inframarginal analysis,this paper discusses the division of labor between hub and spoke,optimizes and preprocesses the situation without any hub and non-hub,obtains the alternative hub and non-hub,and makes the solution of the optimal express network structure more efficient.