Research On Facility Location In Return Network Of Reverse Logistics Based On Heuristics Algorithm

Following the enforcement of environmental protection, the appearance of the relative law and regulations and the endorsement of the economic benefit, the Reverse Logistics has been paid the attention by governments,enterprises and the researchers. The executive of Reverse Logistics can not only make the full use of the resource, protect the environment and promote the continuous economic development of our country; but also accumulate the data of the products for the enterprises and provide the basis for the prediction and decision-making. Nowadays, many famous enterprises in the world have been developed the Reverse Logistics activities, and those have been acted as the effective methods for improving the competence of the enterprises and wining the more economic benefit and the social benefit.The effectiveness of the Reverse Logistics system directly relays on the structure of the Reverse Logistics and also has been limited by it, Thus, a suitable reverse logistics return network must be designed, that is, determine the whole flow channel structure of the return products from the end-users to the originals, including all kinds of facilities, amount and position in reverse logistics and the transportation modes of the return products between the facilities etc. Therefore, to the enterprises, designing the suitable return logistics of the reserve logistics has the great significance in the theory research and in the application. But now seldom research results on the return networks designation of reverse logistics has been obtained in our country.Based on the above background and the research results obtained, the return flows of the products have been analyzed and the return networks designation of reverse logistics has been studied. Firstly, the reverse logistics and the relative concepts have been stated and the activities and the relative technologies of the reverse logistics have been reviewed. Secondly, the reverse logistics network and facilities location have been studied and the different structures of the return networks have been discussed according to the different products and return modes. The location methods on reverse logistics facilities have been summarized. Further, the facilities location problems of the single-period static return networks and multi-period dynamic return networks have been propose din this thesis. With the thought of the mixed integer programming, the return networks of the products in which the nodes are points of return products, the return centers and production sites and the background is considered as markets, return products and resources. The facilities location problems of the single-period static return networks considers the just one location problem, that is, once the position of the facilities has been chosen, it can not be changed. But the facilities location problems of the multi-period dynamic return networks consider the change of the customer demands, that is, the position of the facilities can be change within the different periods because of the change of the customer demands. Finally, the meta-heuristic algorithms have been designed to the single-period static return networks and the multi-period dynamic return networks based on genetic algorithm.By the simulation experiments, considering the trade-off of the transportation fees and deposit fees, the optimal goals of the total cost minimum in reverse logistics have been realized. The comparison analysis has been performed among the results proposed in the thesis and those by the classic genetic algorithm and simulation anneal algorithm to the facilities location of the single-period static return networks problems. The simulation experiments have demonstrated the performance proposed in this thesis to the facilities location of the multi-period dynamic return networks problems.