Research On Reverse Logistics And Its Some Key Issues

Reverse logistics mainly focuses on how to take back the returns and recycle them efficiently and economically. Its goal is to extract more value from the returns or deal with them correctly. It is favorable to saving natural resource, protecting environment, enhancing enterprises competition and increasing economic benefits for enterprises to implement the reverse logistics. As a powerful tool to solve the problems of resource shortage and environment pollution, reverse logistics is paid more attention by academic circles and enterprise circles. Many scholars and companies have studied on it. However, by reviewing the present situation of reverse logistics at home and abroad, it is known that the theoretical studies, the forecasting return and production planning for the hybrid system are still unsatisfactory although substantial results having been achieved in some areas such as reverse logistics network design, inventory control and production planning & shop schedule for remanufacturing. So it is worth for us to keep on studying on it. Aiming at solving the above problems, several research works are done as follows:1. The application backgrounds of reverse logistics are introduced. Its current researches are analyzed and some existing problems are described. The investigative objects are proposed, as well as the research methods2. The conceptual framework of reverse logistics is studied. Based on its present status, a three-layer wheel-shaped conceptual framework is put forward, which is composed of a conception level, an enabler level and an infrastructure level. In the first level, the connotation, elements, classification, basic characteristics, research contents and operation obstacles of reverse logistics are addressed in detail. The enable techniques are analyzed in the second level. The base facilities are discussed in the third level. Some key issues of reverse logistics are presented. The conceptual architecture should make up the gap that the theoretical studies on reverse logistics laged behind its engineering applications.3. Information architecture of reverse logistics is studied. The definition and the function requirements of it are presented. Having considered the shortcomings of the existing information architecture, an information architecture is constructed, which consists of a strategic management system, a planning & resource scheduling system, a coordinated control system, a decision supporting system, a transaction processing systems and information infrastructure. The components of each system and their functions are discussed in detail. The information architecture proposed in this paper possesses such merits, as the rational hierarchical structure and perfect functions, so that it may provide guidance for the designing of the enterprises'reverse logistics information systems.4. Forecasting the return of scrapped products is studied. The concept and the classification of forecasting are addressed. Aiming at the disadvantages of the current forecasting models, such as requirement for more data and narrow application extent, an improved GM(1,1)-transfer function-noise model for forecasting is proposed. In the first stage, the GM(1,1) model improving the generation method of neighborhood system is adopted so as to fulfil the forecasting by only using a few of data. In the second stage, the transfer function-noise model is performed when data amounts reached to 50. The hidden mathematical relationships between the sale quantity and the return quantity are established by the model. Its parameters are determined through model identification, parameters estimation and diagnostic checking. Then, forecasting return is accomplished. Because of being free of probability distribution suppositions for the sale quantity and the return quantity, such as the binomial distribution and the polynomial distribution, the model is more flexible compared to previous forecasting models.5. Production operation management for the hybrid system is studied. The factors leading to the existence of the hybrid system are discussed. After introducing the literatures recently in the field, a production operation model is presented, which integrates disassembly, manufacturing, remanufacturing and procurement. The existing conditions for remanufacturing are evaluated. The influences of the component recovery rate and the minimum returns lag time on the least production cost are analyzed. At the same time, the optimal solution to the integrated production planning is worked out. A numerical example is illustrated to show the feasibility and effectiveness of the operation model. Some practical guidelines are given.6. Considering the engines remanufacturing in Shanghai Volkswagen Allied Developing Company Power Train Branch, a prototype of the reverse logistics production management system (RLPM) is proposed based on the above researches. Its architecture, the characteristics and main functions are introduced. Taking both functions of the forecasting of returns and the production management as examples, it is shown that satisfactory results may arise in the remanufacturing industry when implementing RLPM.