Researches On Some Optimization Problems In Logistics Distribution Under E-Commerce

With quickly development of networking and information technology, Electronic Commerce, which is a new type of business operation, is penetrating every aspects of our life. It fluctuates the base of traditional business operations and marketing theory from many aspects. It also changes practice operation mode of enterprises’external management and trade. Logistics distribution is the key link of carry out Electronic Commerce, and it decides Electronic Commerce’s development level. Research about enterprises’distribution system and their management under Electronic Commerce is significant for enterprises’ success.Logistics distribution under Electronic Commerce has characteristics such as information, networking, automation, intelligence, flexibility, etc. Considering theses characteristics, this paper researches some key optimal problems in logistics distribution, that is, selection of distribution routes and distribution center location problem. The major work focuses on the following five sections:(1) The paper surveys a large number of correlative literatures, and reviews current researches about optimization problems about vehicle scheduling, routes optimization, and distribution center location problem. It discusses status and roles about logistics distribution in Electronic Commerce. It summarizes new characteristics about order delivery problem under Electronic Commerce.(2) Considering characteristics of order delivery problem under Electronic Commerce, this paper constructs single stage and multi-stage mathematical models about vehicle routing problem with information flow, and designs a two-stage heuristics algorithm to solve them. In the first stage, it uses Tabu Search algorithm to solve order delivery problem about orders that have to be delivered at the planning day, that is, basic delivery problem. In the second stage, it considers future information about orders and uses greedy insert algorithm based on evaluation to solve the problem. By using this method, it can delivery part of orders that not arrive the given due date with basic delivery plan and the given method could improve the ratio of usefulness about vehicles and delivery enterprise’s efficiency.(3) According to characteristics of VRPTW under Electronic Commerce, the paper constructs one objective and multi-objective mathematical models about delivery problem. For one objective problem, it researches soft time windows and hard time windows delivery problems, and uses improved Ant Colony algorithm to solve them. For multi-objective problem, objectives are minimization numbers of used vehicles, minimization sum of all vehicles’traveling distance, minimization vehicles’average waiting time, and maximization customers’average satisfaction. Each objective has the same importance. It uses similar Pareto optimal solution set to direct pheromone-updating tactics. This method can let customers have higher satisfaction, reduce vehicles’waiting time, and make delivery enterprises have better fame and higher delivery efficiency.(4) Considering characteristics of backhaul problems under Electronic Commerce, the paper discusses static and dynamic mathematical models about backhaul problem, and designs Adaptive Memory Programming algorithm to solve them. For static problem, it researches mixed vehicle routing problem with backhauls. For dynamic problem, firstly, it decides static delivery route at the beginning of each working day. Secondly, it detects the appearance of new pick-up demand at the end of each time division, and inserts them into the best position of current routes (the position where added distance is minimization). By using this method, it can dynamic adjust vehicle traveling routes according to customers’ demand and vehicles’traveling state, and it can satisfy customers’requirement.(5) The paper discusses the appearance, development of researches about distribution center location problem in logistic distribution. It reviews basic models about distribution center location problem, and reveals the process of intensive study about this aspect. It also discusses construction of mathematical model about distribution center location problem under Electronic Commerce. Based on the existing basic models, it analyzes feasibility of constructing a unitive model. It unifies a lot of basic mathematical models about location problem into one model and this work provides mathematical foundation for the development of distribution center location optimal system under Electronic Commerce.