Reseach On Remanufactuing Inventory Control Theory And Application Under Reverse Logistics Environment

The economy of China in future greatly depends on the sustainable development.It is a great challenge for China to promote sustainable development in an economical way.The industry of circular economic and green manufacturing is developed rapidly and becomes an important power of its economic growth.Remanufacturing is an important branch of green manufacturing which is different from traditional manufacturing.It is used to rebuild products containing the same performance as the original manufactured products,using the end of life products.Remanufacturing logistics involves movement of used products from customers to the remanufacturing facilities,it is different and critical as compared to the forward logistics used for trasporting products from manufacturing facilities to the customers.Moreover,reverse logistics in remanufacturing is complex due to the uncertainity in the returning products.Current research is focused on the methods of optimizing inventory cost in related working areas of reverse logistics by using the traditional logistics inventory control strategies for reference.The proposed inventory strategies are applied to remanufacturing logistics inventory management to analyze the feasibility,significance and limitations of the proposed strategies.The main contribution of this study is divided into four major parts,as described below:1)Research on remanufacturing logistics in the context of deterministic inventory control:The first contribution of the current research is focused mainly on the inventory of recycled products and finished products.Firstly,the research clearly identified and defined the factors of the inventory cost which are composed of inventory cost,remanufacturing cost,replenishment cost and switching cost.Secondly,an inventory control model which is based on economic order quantity(EOQ)method is developed with an aim to minimize total cost in the manufacturing-remanufacturing hybrid systems to determine optimal order quantity and the order batch.The conclusion from the analysis of the proposed model indicates that the proposed inventory control model is an optimal inventory control strategy when the order batch for remanufacturing and manufacturing is odd number.However,the proposed inventory control model is not significant when the order batch for remanufacturing and manufacturing is even number.2)Research on inventory control of stochastic remanufacturing logistic:The second main contribution of the current research is implementation of the proposed inventory model to solve the inventory problems related with recycled products and finished products.Moreover,the proposed model is expanded for discrete stochastic process of remanufacturing production in the current study.Furthermore,a dynamic programming model is made and the inventory variable is assumed to obey Markov chain property for the proposed problem.Additionally,different scenarios are considered for ordering cost and switching cost.Moreover,an improved inventory control strategy(s'S)equation is considered as constraint of the problem which is solved to get optimal cost under the constraint of different scenarios.The results based on the proposed inventory policy are compared with the results obtained from the real optimal strategy which do not have any inventory policy to constraint the cost.The results indicate that the proposed improved inventory control strategy(s'S)can greatly enhance the computational efficiency and keeps the error within acceptable limits.3)Research on inventory control of remanufacturing logistic oriented for enterprise resource scheduling:The third main contribution of the current research is the extension of research to multi material and multi-level inventory problem.The problem of the remanufacturing process,i.e.,recycle,disassembly,remanufacturing etc.is took into consideration during allocation of different resources of company.The proposed research formulated a general mathematical model for the multi replenishment methods in remanufacturing process.Moreover,the proposed general model is simplified according to the case company problem.In addition,the capacity constraint equations for each remanufacturing process are prepared for enterprise resource allocation.Furthermore,an optimization algorithm for the corresponding case company problem is designed to investigate different inventory control policies for different resource allocation methods to provide guidance for enterprise practice.4)Development of management platform for remanufacturing inventory control:The fourth main contribution of the current work is the implementation of the proposed mathematical models to develop management platform for the case company.Current research presented the requirement for the development of management platform for the case company investigated.Furthermore,the functional structure of software platform is presented on basis of the theoretical research of the current study and the business processes of real remanufacturing case company,In addition,the rest of this dissertation introduces the function module and characteristic of the proposed platform.Moreover,the performance of the proposed platform used in the real project of the case company is also presented in the current research.At the end,the conclusion of the whole research is summarized and the research forcus in future is described.