Events like the 9/11 terrorist attack on the World Trade Center and the 11-day work stoppage at 29 West Coast ports have exposed the vulnerabilities of a key element of America's economic infrastructure-business supply chains. To sustain business in today's new risk environment, it is necessary to assess the vulnerability of business chains and develop continuity and operational plans to mitigate consequences and assure continuation of critical processes. This paper reviews existing techniques used in decision making for risk analysis and presents a modeling and analysis framework for assessing business risk and evaluating safeguards to secure the supply chain.

An algorithm is developed to determine disassembly levels and bins to maximize the profit from a used product through balancing the resource invested in disassembly processes, the return realized from them and the environmental impact. The algorithm utilizes the information from a computer aided design (CAD) system and requires minimal user input with the computational complexity of O(n), where n is the number of parts and final subassemblies in a product. It has been successfully used in the development of a demanufacturing stage of a multilifecycle assessment and analysis (MLCA) tool. The benefit of the proposed algorithm is illustrated through an example.

As an integral part of a product life cycle, demanufacturing is a process of disassembling a product and assigning collection bins for the resultant subassemblies and parts, which are then reused, remanufactured, reengineered, or disposed of. This paper proposes an algorithm to determine disassembly levels and bins in an integrated way to maximize the profit from a used product through balancing the resource invested in disassembly processes, the return, and the environmental impact caused by them. The algorithm utilizes the information from a computer-aided design system and requires minimal user input with the computational complexity of O(n/sup 2/+mn), where n is the number of parts and final subassemblies in a product, and m is the number of collection bins. It has been successfully used in the development of a demanufacturing stage of a multi-life cycle assessment and analysis tool. The benefit of the proposed algorithm is illustrated through a laptop computer example.

A Multi-Lifecycle Assessment and Analysis (MLCA) Tool is developed to apply the MLCA methodology on electronic products and help designers evaluate environmental performance of their products. The design and development of a demanufacturing stage, one of the main stages in the MLCA tool, is emphasized. The work includes disassembly planning, bin specification, bin process definition and analysis report. The developed algorithm for bin assignment requires minimal user input. An improved algorithm, which requires more data information, is proposed to achieve more benefits from a used product. Based on the data associated with each process for bins, the reports about cost, environmental burden, and energy consumption can be obtained so that users cart make the best decisions on the end-of-life management of a product by balancing economical and environmental needs.

Industrial demanufacturing is a practice of growing importance due to increasing environmental and economic pressures. However, very little research focuses on it from a system perspective. This paper presents a disassembly planning and demanufacturing scheduling method for an integrated flexible demanufacturing system. Workstation Petri net and Product Petri net are proposed for its hierarchical and modular modeling in order to derive the disassembly path with the maximal end-of-life value. Scheduling Petri net is introduced to schedule the demanufacturing resources. The proposed methodology and algorithms are demonstrated through the disassembly of personal computers in an integrated flexible demanufacturing system.

Industrial recycling and remanufacturing is practice of growing importance due to the increasing environmental and economic pressures. It involves product disassembly to retrieve the desired parts and/or subassemblies by separating a product into its constituencies. The disassembly process modeling and planning is more challenging than assembly since its termination goal is not necessarily fixed depending on the system status. Moreover, it is uncontested that disassembly is charged with more uncertainty in system structures and component conditions than assembly. The paper reviews methods for modeling and process planning in disassembly. Its purpose is to survey the state-of-the-art of this emerging area to supply important information for future study.

Presents a life cycle engineering approach to the development of flexible manufacturing systems (FMSs). FMS machine selection and decisions along its life are considered. The latter include, for example, how many times a particular FMS component should be upgraded. Life cycle decision-making is based on cost, benefit, and environmental impact of an FMS. The proposed approach provides a new way to develop cost-effective, high-quality, and environmentally conscious FMS.

Design-for-retirement is a concept that allows one to design a product such that its retirement time and post-life treatment are optimized, i.e., its environmental impact is minimized and financial gain is maximized. Retired products face four primary multilifecycle engineering treatments: 1) to recondition for reuse in the next lifecycle; 2) to convert into a material form for recycling back into new parts, 3) to disassemble into several components for further assessment and 4) to landfill. Each option has a different environmental cost-benefit ratio. This paper proposes several matrices to represent the connection information, interference directions among nodes, and disassembly complexity. It presents a method to evaluate a design in terms of cost and apply it to two personal computer designs.

This paper presents a hybrid search algorithm for scheduling flexible manufacturing systems (FMS). The algorithm combines heuristic best-first strategy with controlled backtracking strategy. Timed (place) Petri nets are used for problem representation. Their use allows to explicitly formulate concurrent activities, multiple resources sharing, precedence constraints and dynamic routing in FMS operation. The hybrid heuristic search algorithm is combined with the execution of the timed Petri nets to search for an optimal or near-optimal and deadlock-free schedule. The backtracking strategy is controllable. One can only employ the pure best-first search to obtain an optimal schedule thanks to a proposed admissible heuristic function. The presented method is illustrated through an FMS scheduling problem.