An Improvement To Table-Working Method And Its Application To Approximate Supply And Demand Balancing Problems

With the development of market economy of China, the logistics, which regardedas the third profit source, has become more and more important. The distribution ofmaterials plays an important role between the supply-side and the demand-side, andwins the widespread concern. Thus, the rational optimization of delivery vehiclerouting, which also called VRP (Vehicle Routing Problem), become extremelyimportant. It can help reduce logistics cost as while improve efficiency. We analyzethe vehicle routing problem, and then make the further study of vehicle routingproblem based on multi-distribution center. The important research of this paper list asfollows:First of all, this paper makes the research on the classical algorithm of vehiclerouting problem and the new study of this field in recent years. At the same time,analyzes and summarizes the connotation of the vehicle routing problem, the basicidea, the classification and description of the algorithm. Among, we introduce theexact algorithm, the traditional heuristic algorithm and the classical heuristicalgorithm. And around this, we make analysis and comparison of the above algorithm.Secondly, this paper describes the study on transportation problem in recentyears. We divided the transportation problem into four categories, and gave thecorresponding mathematical model respectively. This paper also introduces the newstudy of the single-objective and the multi-objective transportation problem, in whichit highlights the study of the Tabular method and the steps of the specific algorithm. Inaddition, this paper introduces the specific adjustment steps for different situations.Then, on the basis of the brief introduction of the background of the vehiclerouting problem and the transportation problem, and based on the study of existingmaterial distribution vehicle routing problem, we propose a new way based on theminimum element method for solving the single distribution center vehicle routingproblem. Firstly, increase the corresponding temporary node C to meet a certainamount of the materials for all the demand points. Secondly, improve the process ofmaterial distribution to raise the quality of service. This can not only save transportcosts effectively, but also reduce the number of vehicle scheduling. At the same time, it gives the applicable standards for this improved method.Next, we analyze the complex logistics network environment presently.According to the vehicle routing problem based on the two layer distribution centerwe propose a new method based on the improved table-manipulation to solve it. Thismethod establish in the four layers involves the supply-side, two-layer logisticdistribution and the demand-side of logistics network model. The Dijkstra algorithmis used to calculate the shortest distance between supply-side and demand-side, andtransform it into the supply and demand balance table. Then it makes use of algorithmwhich combines the Tabular method and save-mileage method to solve the model offour-layer logistics network. The results show that this algorithm can guarantee theleast total cost of transportation, at the same time, it can effectively reduce the numberof vehicle schedule in the process of delivery.After that, based on the description of the logistic network model, this papergives the definition of the issues approximate to balance between supply and demandpoints. After the convention into the supply and demand balance table, this papersolves the problems with the Tabular method.Finally, work of the thesis is summarized, and some recommend is proposed forsolving the existing problems.