Research On Organization Optimization Of Local Scattered Freight Express Train Considering The Transit Time Limit

The railway freight reform of China happened in 2013.From then on,Chinese Railway has gradually attached importance to the transportation of scattered goods.In order to compete for scattered goods market,all railway bureaus have dispatched inner and inter bureau cargo express trains,which accept scattered goods widely in any time and provide“door to door“transport service.And the railway enterprise reform the transportation organization mode,in which it can make transport plan to arrange shipment timely and to improve transport efficiency according to customer's transport demand.As the first unit to implement the reform of Chinese Railway,Beijing Railway Bureau dispatched JingJinJi cargo express trains according to the characteristics of the stations and railway lines,covering almost all districts and counties of Beijing,Tianjin and Hebei.And it not only provides a more efficient,safe and economical transport mode for people,but also creates a way for the integration of Beijing,Tianjin and Hebei.But JingJinJi cargo express trains operate for a short time have no systematic management idea or advanced technology.And with the continuous development of freight volume,ability of some stations becomes tight.It is difficult to ensure the goods delivery deadline.Therefore,the job of this paper is to compress the overall transport time and ensure the goods delivery deadline by arranging the train stop choice and operation time reasonably in the precondition basic station operating requirements.The main work of this article is as follows.(1)This article analyzed the present situation of the railway freight transportation development in our country,and clarified the background and significance of the research.Then it summarized and analyzed the transit time limit,cargo express service and freight transportation organization at home and abroad.(2)This article made the introduction of the development status quo of Chinese scattered express,and made clear of the cargo express service processes and express train operation organization mode.And it introduced the concept and calculation method of transit time limit,and made an analysis of the problems of transit time limit guarantee.(3)This article established the optimization model of cargo express train operation organization.Taking account of the operational requirements and the ability of the train,the model took the reasonable stop choice and the amount of loading and unloading as the decision variables to achieve the purpose of speeding up the organization of train operation and shortening the time of freight transportation.(4)Then we designed the algorithm for the model.Using the penalty function method,we transform the model into another optimization problem without constraints,and then the microevolution algorithm is used to solve the model.(5)The last part was the example analysis.Beijing-Tianjin-Hebei link cargo express was taken as the example of the analysis object.Based on the actual data,we wrote algorithm code in the MATLAB software,and then run the solution.Then the results of the operation were analyzed,and we verified the correctness of model and feasibility of algorithm.