Research On Optimization Of Urban Logistics Distribution Path Based On Dynamic Traffic Network

Vehicle routing problem(VRP)is a very important problem in modern logistics management research.With the rapid development of society and economy,people's demand for cargo transportation and distribution is increasing,the proportion of door-to-door logistics services is rising,and the distribution pressure is the outstanding problem faced by the logistics enterprises responsible for the end logistics and distribution.At the same time,The increasing number of residents,the continuous expansion of urban scale,traffic congestion has seriously affected the logistics of the end of the distribution efficiency,which is the city logistics enterprises are facing another prominent problem.How to effectively arrange the logistics transport vehicles in a limited time,through a reasonable arrangement of distribution vehicles and travel time to overcome the traffic congestion in the case of the minimum distribution costs to complete the distribution task to achieve efficient logistics and distribution system cost The operation of today's logistics industry is an urgent problem to be solved.Therefore,it is of great practical significance to study the vehicle routing problem based on dynamic traffic network.According to the above background,this paper studies the Time-dependent Vehicle Routing Problem With Time Windows(TDVRPTW)based on dynamic traffic network.Based on the theory of urban logistics distribution and dynamic transportation network,aiming at the problem of the vehicle routing planning with time window(VRPTW),considering the influence of logistics operation,the distance of distribution and the timeliness of distribution on the distribution cost,The VRPTW path planning model with the minimum delivery cost is the penalty function,and then the VRPTW path planning model is expanded considering the dynamic traffic environment,and the TDVRPTW pathplanning model in time-varying environment is constructed.Through the comparison and analysis of various algorithms,the genetic algorithm is used as the solution algorithm of the logistics distribution path planning model in this paper.The chromosomal coding method and the selection of genetic evolution function,cross,mutation and so on are designed to solve the problem model.Based on the mentioned model and optimization method,we use the internationally accepted standard example library and Shenzhen real logistics distribution case to verify.The experimental results show that:(1)According to the VRPTW model under non-time-varying conditions,the genetic algorithm designed in this paper is used to verify the internationally accepted standard example library.The solution is close to the existing optimal solution.And the algorithm is effective and feasible;(2)The VRPTW model and the TDVRPTW model are compared with the results obtained by the algorithm in the dynamic traffic network.It is found that the total distance and the total time of the vehicle traveling in the TDVRPTW model result are in a certain degree.It proves that traffic factors have an impact on logistics distribution;(3)The logistics distribution in the dynamic traffic network environment is closer to the reality of urban logistics and distribution.