The Application Of Simulated Annealing In Vehicle Routing Problem With Time Windows

Modern logistics, an advanced technology for companies, which plays a significant role in the development of economy and society, is regarded as an important way of lowering cost and enhancing productivity. In the distribution system, a scientific and rational vehicle routing method will not only reduce the cost, but also increase the circulation speed, improve the operation efficiency and raise the service level.In the distribution system, the vehicle routing problem is a NP-hard problem, which was first raise by Dantzig and Ramser in 1959. As many problems can be attributed to this problem abstractly, many experts and scientists in the area of operation research, application mathematics, combination mathematics, logistics science, compute science and transportation planner attach great importance about it, and it always be the hottest problem in the area of operation research and combination optimization in recent years.Based on the work already achieved, the vehicle routing problem with time windows (VRPTW) is studied in this paper. VRPTW consists of designing vehicle routes and schedules for users who have some quantity of good to deliver and a service time window, the object is to serve all users and have a lowest costs. The property of this problem is analyzed and the simulated annealing is used to solve this problem. Firstly, the initial feasible solution is constructed by the sweep method and secondly, the simulated annealing and 2-interchange technical are used to improve the solution. The simulation of this algorithm is processed, and it can solve the VRPTW for a number of customers. In the end, the analysis of the parameter is given.