Study Of Optimizing Model On Railway Empty Car Distribution

The adjustment of empty wagon is one of the important elements of railway transportation technical program and is also significant guidance to transport production. Obviously, empty wagon distribution plays an important role in the effieiency of rail car utilization,the degree of meeting freight demand,and the modernization of railway operation.lt represents technically an optimizing problem of reasonably wagon usage.The research on models and algorithms of empty wagon distribution makes signifigant sense in both theory and practice.The paper focuses on theoretical research, plentifully uses former results for reference, introduces systematic science、analogy and means of mathematic models, and combines theoretics of correlated knowledge, such as discrete math, optimization and computation etc. to deeply analyze the optimizing problem of empty wagon distribution among railway nodes to achieve the purpose of providing a new modeling thought and resolving algorithm.The main content and conclusion includes:(1) Depicting and analyzing the sources, adjusting principles and ways of empty wagons in detail.(2)Through analyzing the characteristics of traditional empty car distribution model, based on the model of empty wagon distribution with multiple car types, paper constructs the Model of Empty Car Distribution with substitution of car Types(IMEDST).Its objective function is as the maximum of total transportation’s benefit. And it analyzed in detail the characteristics of model and determined the relevant technical index.The two core problems of empty car distribution are quantity distribution and network matching flow. After describing abstractly the problem, they were optimized separately. Then coordinating them according the characteristics between them, the TP model is constructed.(3)It introduced the principle, algorithm form and application circs of ACO which is selected to be the method to solve the optimizing model of empty wagon distribution. Then the ACO of TP model is designed. After the example analysis of IMEDST, the model is proved to be closer to empty car distribution practice.(4) Based on the analysis of the existing algorithm, ACO algorithm of empty wagon distribution is devised. At the same time, parameters in the algorithm and its convergence and time.complexity are analyzed. With instances, the paper compares the validity of varied algorithms and draws the conclusion that ACO is superior for TP model.The research work and conclusion of the paper are hopeful to advance more development in the empty wagon distribution problem.