Research On Optimization Of Transportation Organization Of China Railway Express Based On Hub Assembly

CHINA RAILWAY(CR)Express is an is an important means of land transport connecting China and Europe to implement the Belt and Road Initiative.Its operation and development open the overland trade channel between Asia and Europe,conform to the historical trend of realizing the great rejuvenation of the Chinese nation.As the pandemic spreads around the world,international flights have been slashing,global shipping congestion has been aggravating.However,CR Express persist in operating despite sea and shipping disruptions,which has continued to play a role in the prevention and control of the epidemic,the resumption of production,and the assurance of the global supply chain.But there are also some development barriers with CR Express at present.We will focus on optimizing the transportation organization of CR Express,solve the existing problems of CR Express,improve the service level,brand image and timeliness of transportation services,and inject transportation vitality into the Silk Road Economic Belt.The research content of this paper mainly includes the following three parts:(1)Optimize the transportation organization mode of CR Express,put forward the transportation organization mode based on hub assembly,and give the implementation strategy.This paper analyzes the current situation of the development and the main bodies of the freight transportation organization system of CR Express,summarizes existing problems of CR Express,including single transport mode,very long assembling time,low load factors,difficult implementation of the "3 trains to 2 trains" policy and so on,with all the problems into four categories: transport organization,service level,hardware facility and policy.In view of the above problems,this paper proposes the transportation organization mode of CR Express based on hub assembly,which has the characteristics of fixed train formation,loading and unloading on arrival and departure lines,diversified transportation,and can make the policy of "3 trains to 2 trains" implemented.In order to optimize the transportation organization mode,this paper puts forward the implementation strategies,including building a unified combined transportation service platform,optimizing transportation organization,and promoting extensive consultation,joint contribution and shared benefits among countries along the Belt and Road.(2)Comprehensively optimize the hub station location scheme and operation plan of CR Express.Making the minimal comprehensive transportation cost and station reconstruction cost as objective,we build a comprehensive optimization model for the hub station location scheme and operation plan of CR Express with the constraints on the transportation demand,the operation capacity of the hub station,the reloading capacity of the port station,etc.,to optimize the key problems of transportation organization such as the route selection,the transit hub station location scheme and the train operation plan.16 domestic freight stations and 11 foreign stations are selected in case study.We call GUROBI,a large-scale solver of operational research problems,to solve the model through MATLAB platform.The sensitivity analysis is carried out on the operation capacity of the hub station,the reloading capacity of the port station,etc.The experimental results show that the total cost of the transportation organization mode based on hub assembly is lower than that of the all-direct mode,which reflects the better economy and timeliness of the new transportation organization mode.(3)Compile the planning diagram.To ease the operation pressure of transport corridors and port stations,and coordinate the contradiction between the weekly operation plan of CR Express and the daily railway train diagrams,we construct the compilation model of CR Express planning diagram based on consolidation of train paths,which takes the minimization of the total container consuming time,container consuming time due to train stop and so on as the objective functions,takes the transportation demand,station interval time,the feasible region of train departure time,consolidation of train paths and so on as the constraint conditions.In this paper,14 domestic and 11 foreign railway stations are selected as examples,a weekly planning diagram is compiled,and the operation results and train stop time are analyzed.The calculation results show that the planning diagram compiled by the model makes the time for trains to start,pass through trunk lines and arrive at port stations more uniform and orderly by consolidating the CR Express paths on trunk lines,which helps to relieve the capacity strain of transport channels and port stations.There are 19 figures,18 tables and 86 references in this paper.