Study On LRP Model Of Express Network On Combined Transport By Highway And Railway

With the extensive development of the modern electronic commerce,the requirements of express consignment currency are increasingly high,as well as wide application and the advantage in transportation of high-speed railway network.it is possible for road-rail multimodal transport based on high-speed railway express.And the highway transportation network as an important part of highway and railway combined transport network,whether the location allocation problem and vehicle routing problem are reasonable or not play a very important role in the efficiency of express delivery to the customer and logistics cost savings.Therefore,studying how to build terminal distribution network of the road-rail multimodal transport express delivery and implement Door-to-Door Transportation is of great practical significance to the development of modern logistics.Firstly,this paper elaborates correlation theory about road-rail multimodal transport,express network,delivery and pickup,define the meaning of express network of combined transport by highway and railway,meanwhile the location routing problem is introduced.It points out the meaning of location allocation problem,vehicle routing problem,location routing problem and the inherent link between them,and illustrates solution of location routing problem,at last,the theory of genetic algorithm is introduced.Then,based on the analysis the problems of railway freight,the high-speed railway express delivery experience of developed country,considering the cost and efficiency of high-speed railway express,the result shows that the implementation of the necessity and feasibility of high-speed railway express.Meanwhile,After the study of transport mode and development countermeasure of high-speed railway express,this paper puts forward development of highway and railway combined transport and designs the express network,through the analysis of the characteristics of the network.In the end,the research object is identified for the location routing problem of express terminal distribution network.Finally,in the background of express terminal distribution network,through the analysis of the vehicle capacity and time window constraints,this paper builds a location routing problem model with soft time windows and integrated delivery and pickup.Then,according to the model,this paper designs the genetic algorithm program,and analyses the program by numerical simulation.Moreover the validity of the model and algorithm is verified in this paper.though the sensitivity and stability of the algorithm are studied by using different parameters and the performance of the algorithm is also analyzed.The main innovation of this paper is to define the meaning of express network of combined transport by highway and railway and build the express network based on the characteristics of high-speed railway express.the research object of this paper is the location routing problem of express terminal distribution network.According to the rail-road combined transportation with high added value,high efficiency of the characteristics and the actual node demand,this paper builds the model of location routing problem with soft time windows and integrated delivery and pickup,Considering the minimum cost of logistics system,a genetic algorithm with a stage of solving LRP model is designed.