Optimal Design Of Remanufacturing Logistics Networks With Original Equipment Manufacturer Management

Remanufacturing is the process of transforming used products into those which satisfy exactly the same quality and other standards as the new products. Remanufacturing is accomplished through necessary disassembly, inspection and repair as well as replacement of components or parts. Because remanufacturing reuses affiliated value of the used product as possible as it can, also plays an important role in reducing environment pollution, saving natural resource and promoting sustainable development of national economy, special attention is given to remanufacturing in many countries, especially advanced industrial countries. Up to now, the product that is suitable for remanufacturing is mostly used mechanical or electronic product. Due to the obligation of extended producer responsibility and the requirement of the corporation's inner benefit, original equipment manufacturer (OEM) answering for remanufacturing becomes a developing and further tendency, so it is the time that OEM must face and consider the management problems of its remanufacturing logistics. When OEM manages remanufacturing logistics, OEM can plan its all logistics activities as a whole and the logistics network is more complex than traditional network. Therefore, it is worthy to do an in-depth study about this kind of network's design problems.Based on the existing literatures and aiming at the characteristics of remanufacturing logistics networks, the multi-period location models under certainty and some approaches under uncertainty for optimal design of the manufacturing/remanufacturing (M/R) logistics networks are studied respectively. The main contents of this dissertation are as follows:(1) The developing progress of the optimal design of remanufacturing logistics networks at home and abroad is reviewed, the shortcomings of existing research on the problems are pointed out and research framework of this dissertation is put forward.(2) The connotations of remanufacturing and remanufacturing logistics are discussed, the characteristics and structural features of remanufacturing logistics networks are summarized and the preparative work before the network's optimal design is expounded.(3) The multi-period location models with OEM management under certainty for optimal design of the remanufacturing logistics networks are studied.Firstly, considering the design parameter's difference between different periods in a short planning horizon, a multi-period static location model for optimal design of the M/R logistics network is presented. The model solves the integrated design problems by treating traditional logistics network and remanufacturing logistics network as well as forward logistics facilities and reverse logistics facilities simultaneously. It links up the logistics of every inter-related time period into a single stretch by the lack or oversupply amount of the new product or remanufacturing product and the quantity of unreturned used product at every period-end at every consumer zone. The conclusion resulting from the model is suitable for tactical logistics operation management or corresponding schedule arrangement of the corporation.Secondly, considering the design parameter's difference between different periods in a long planning horizon, a multi-period dynamic location model for optimal design of the M/R logistics network is developed based on the multi-period static location model. This model takes into account time value of expense, establishing time of logistics facility and the relation between establishing time and operation period of logistics facility simultaneously. With the help of the model, appropriate sites of all logistics facility types and sound logistics volume between corresponding facilities of every period can be obtained. The conclusion resulting from this model is suitable for strategic logistics operation management or corresponding schedule arrangement of the corporation.Finally, considering the possibility of logistics facility's capacity expansion, an extended multi-period dynamic location model for optimal design of the M/R logistics network is proposed based on aforementioned model. The extended model takes into account facility's dynamic location, dynamic enlarging and facility capacity's dynamic expanding simultaneously. With the help of the model, appropriate open sites and open numbers of all logistics facility types and associated logistics volume between corresponding facilities of every period can be got, while the sites and numbers of facilities that need expanded and the standard modules that will be expanded at necessary facilities of every period can be achieved. Since these models are mixed integer non-linear programming models, some mixed genetic algorithms are presented and associated numerical examples are given respectively.(4) Some approaches with OEM management under uncertainty for optimal design of the remanufacturing logistics networks are studied.Firstly, considering uncertainty of new product's demand and used product's return, a two-stage stochastic programming model is developed by the way of Monte Carlo simulation sampling techniques. The model's computation efficiency is administrated by sample quantity and the model can be solved by the calculations of mixed genetic algorithm. According to sample average approximation method, optimal value's upper and lower bounds approaching techniques to acquire good objective value and corresponding feasible solutions are expounded. In order to get a robust M/R logistics network, the feasible networks resulting from time after time necessary optimizations are estimated by using a group of larger quantity samples and logistics network's optimal design steps based on two-stage stochastic programming are summarized.Secondly, with respect to shortcomings of sample average approximation method and owner's desire to logistics network, the sample average approximation method is extended by introducing network's applicable probability and network's applicable confidence level. The extended method takes into account calculation accuracy of optimal value under given confidence level. With the help of the extended method, the stochastic programming problem's robust solution that can meet owner's desire can be got. Therefore, the extended model has good maneuverability.Thirdly, regarding product's absolute quantity as decision-making variable of logistics distribution, a fuzzy mixed integer linear programming model is presented. The model treats the quantity of recycled product, the demand of new or remanufactured product and the production or processing capability of logistics facility as the type of triangle or tolerance fuzzy parameters, and can optimize facility open site and facility type simultaneously. The model's confidence level of fuzzy constraint is independent, so it is convenient for the application of fuzzy chance constrained programming method. In order to appraise the confidence level of fuzzy constraint, an analysis method for judging the confidence level's importance degree is presented.Finally, the optimal design approach with fuzzy and stochastic parameters for integrated M/R logistics network is discussed based on aforementioned research. These means effectively decrease decision-making risk under uncertain information.