VLSN Algorithm Based Hub Location & Service Frequencies Determinations In Intermodal Freight Transportation Network

As a very important aspect of the construction of freight network under intermodal transportation system,the hub location problem is now attracting more and more researchers' attention on intermodal transport.Traditional logistics center location or hub location methods for single transport mode(road,rail or other modes) are now not able to meet the development requirements of intermodal transportation due to the aspects concerned unable to accord with the reality.This paper establishes the hub location model for the intermodal freight transportation network on the basis of describing the intermodal freight network and characteristics of the hubs.In the hub location model,we insert service frequency as decision variables,solve the problem with very large scale neighborhood search(VLSN) algorithm in the process of iteration,and determine the hubs of the intermodal freight network under the circumstances of service frequency unchanged and the freight assignments between hubs for different transport modes.The main work of this thesis includes the following aspects:1.Analyzing the hub characteristics of intermodal freight network and the establishing method of the network;2.Analyzing the methods of hub location of the freight network or logistics center and the influence factors of the hub location problem for the intermodal freight network;3.Establishing the hub location model of the intermodal freight network with service frequency taken into account,give the solution steps with iteration,transform the hub location problem to the capacitated minimum spanning tree problem(CMST);4.Solving the capacitated minimum spanning tree problem(CMST) with VLSN algorithm;5.Analyzing the computational experiment and prove the reliability of the model and the effectiveness of the algorithm.