Drop And Pull Vehicle Routing Problem Based On Hub And Spoke Network

In the recent years,with the rapid development of China’s economy,the domestic logistics industry has developed rapidly.However,the "small,scattered and chaotic" situation of domestic logistics is still very serious.The overall logistics and transportation efficiency is low,and the total social logistics cost stays in a high level.The state has raised a series of measures in order to solve these difficult problems,the promotion of Drop and Pull Transport has a high position in it.As the most popular and advanced transport in the world,Drop and Pull Transport occupies 70%~80% transportation volume in some developed countries.The main advantage is that it can fully utilize the characteristics of tractor and semitrailer which can flexible separation and combination,to achieve the loading point loading,unloading point and unloading operations and synchronize to road transport operations,so as to shorten the suspend operation time which caused by tractor waiting for the unloading,maximize the transportation efficiency,reduce logistics cost.When most domestic logistics enterprises use the drop and pull transport,the problem of inefficient transportation and logistics is still very serious due to the unreasonable transportation mode and imperfect formulation of scheduling schemes.Therefore,the research on the problem of hanging and hanging transportation has become one of the important subjects of many scholars,which has important practical significance.The main work and contribution of this article are as follows:(1)Put forward the organization model of "shaft and spoke network dump".This is a mixed organization model which is raised after fully analyzing the four basic transport organization models.(2)Design a vehicle scheduling model based on hub and spoke network.The model is combined with the organization model of "spokes network dump" and the actual express company situation.It is more practical.(3)Improved greedy algorithm.Greedy algorithm is outstanding in many algorithms because of its simple calculation process and high calculation speed,but greedy algorithm itself is prone to local optimum problem.Therefore,the aim of this paper is to improve the greedy algorithm,and get the solution which is closer to the global optimal.Finally,this article analyse the case based on the real data collection from BEST FREIGHT.The result of case analysis shows that the model and algorithm of the dump transport vehicle scheduling based on the hub and spoke network and the algorithm are practical and effective.It is of great significance to improve the efficiency of logistics transportation.