Research On Node Layout And Scheme Of Railway Express Freight Transportation

In recent years,China's logistics industry has developed rapidly,and the total market traffic has been rising.In the traditional logistics industry,road transport and air transport are the main modes of transport.However,with the continuous development of China's high-speed railway,the transportation mode of railway express freight transportation referred to as railway express)has gradually developed.Although the railway express has the advantages of safety,convenience and high efficiency,due to the unreasonable node layout and the immature transportation scheme,the railway express cannot fully adapt to the current market competition environment of the logistics industry,and the development is relatively slow.In order to improve the transportation mode of the existing railway express,the Railway Corporation has implemented the reform of railway freight transport,starting from the improvement of profitability and vigorously developing the railway express business.In this context,this thesis takes the layout of railway express nodes and reduces the cost of railway express as the research direction.(1)Analyze the research status of railway express at home and abroad,and find that the research results at home and abroad are mainly concentrated on the feasibility study of railway express and the mode of transportation organization.There is little research on the layout and transportation scheme of railway express node.The research direction provides clues.(2)Analyze the system and market of railway express,analyze it from the aspects of market traffic volume,transportation organization mode and input and output,and find that the railway express train model is more suitable for the future logistics development environment,potentially huge market share.(3)Analyze the problem of railway express service network,and construct a bi-level planning model of railway express service network.The model takes the lowest cost of railway express transportation as the objective function,the volume distribution and transportation route are selected as decision variables,and the optimized is designed.Plant growth simulation algorithm that use variable step sizes to search for solution space.(4)Analyze the data factors affecting the layout of railway express nodes,and rationally arrange the nodes of railway express.Apply Python programming to calculate the shortest path between nodes,provide data foundation for model solving,and then apply the plant growth simulation algorithm to the bi-level planning of transportation service network based on the OD data between nodes in the actual project "Railway Layout Planning and Implementation Plan".Applying plant growth simulation algorithm to solve the bi-level planning model of transportation service network.The research results show that the model can be applied to the existing road network structure and get the optimal transportation plan,so that the transportation cost of the railway express delivery enterprise is the smallest.