Design and analysis of disassembly and remanufacturing systems in the electronics industry.

摘要

Interest in the area of disassembly and remanufacturing in the electronics industry has intensified in recent years. The abundance of scrapped products after their use has triggered a demand for reusable electronic components, priced at a fraction of the new components. As a result, manufacturers have started to realize that they must turn their attention to the development of new methodologies for reverse logistics. This dissertation addresses this need.; The reverse logistics problem encompasses many different characteristics of environmentally conscious manufacturing and planning, including disassembly, reuse, recycling, and remanufacturing. Reverse logistics is gaining increased attention not only because of environmental factors but also for economic reasons.; In this research, five main techniques are employed to solve five different problems.; The first technique addresses the need for designing products for disassembly. Product design is the dominant factor that influences the ease by which the product can be taken apart at the end of its life. All efforts involved in reverse logistics would be futile without initially designing products for disassembly. The technique involves solving the problem in one of two ways. The first way enumerates the different combinations for retrieving the components based on an objective function consisting of four variables in order to find the largest value of the Design for Disassembly Index (DfDI). The second way employs an Integer Programming (IP) approach to find the optimal DfDI.; The second technique develops a heuristic scheduling methodology to solve the sequencing of a two-stage disassembly/retrieval process. A scheduling heuristic is used to optimize the processing time of the overall process with respect to the product structure. The uniqueness of this approach is that it allows a process planner to breakdown the product's bill-of-materials into modules, each consisting of functional component groups. The heuristic first optimizes the processing time of each stage (resulting in an optimal sub-sequence) and later combines the sub-sequences to make a complete optimal disassembly/retrieval process plan.; The third technique uses Case-Based Reasoning (CBR) to quickly generate disassembly process plans in order to prevent interruptions during disassembly operations. CBR is a technique which allows a process planner to rapidly retrieve, reuse, revise, and retain solutions to past disassembly problems. As a result, CBR allows uninterrupted disassembly of a variety of products in a multiple-product/multiple-manufacturer environment.; The fourth technique addresses the lot-sizing problem for product disassembly. For disassembly, reverse logistics usually consists of a mixed batch of products. Since different products yield different combinations of components, finding an optimal lot-size of products to disassemble is often desired. In this dissertation, this problem is solved using Integer Programming.; The final technique optimizes a bi-directional supply chain system using a sophisticated reverse flow (from the end of lease, end-of-life, and/or returned products) for product remanufacturing. With a forecasted demand for certain remanufactured items within a planning horizon, the technique uses a modification of the Materials Requirements Planning (MRP) approach to find the number of components to retrieve in different periods for remanufacturing. After remanufacturing, the “like-new” products are reintroduced back to consumers.; In sum, the above-mentioned innovative approaches to problems associated with reverse logistics, lead to optimum use of resources without compromising the quality of our environment.