Applied Optimization Research Papers - Academia.edu (original) (raw)

Today's supply chains are becoming not only more efficient with the aid of advanced information technologies, but also riskier due to the tight interconnectedness of numerous chain links that are prone to breakdowns, disruptions or... more

Today's supply chains are becoming not only more efficient with the aid of advanced information technologies, but also riskier due to the tight interconnectedness of numerous chain links that are prone to breakdowns, disruptions or disasters. Although many studies focusing on business risks in various contexts have been presented in the literature over the years, research effort devoted to understanding the risks associated with suppliers and the supply market has been limited, especially from a quantitative point of view. In this chapter, we first, through extensive literature view, present a taxonomy of supply-side risks, a four-step supply risk management process, and a list of techniques that help accomplish each step. Then we propose two optimization-based decision tree models that effectively formulate two decision-making situations in which the questions of how many suppliers should be used and whether to use standby suppliers are addressed. Future research directions are also suggested.

This paper addresses logistics decisions for an aviation firm and its joint venture in Chengdu, China. The major logistics cost items for outsourcing aircraft engine components to the joint venture are identified and a number of... more

This paper addresses logistics decisions for an aviation firm and its joint venture in Chengdu, China. The major logistics cost items for outsourcing aircraft engine components to the joint venture are identified and a number of transportation alternatives are examined based on cost effectiveness. Under the current structure of the company’s global supply chain, we have evaluated five transportation options for moving materials inbound and outbound: all air, water-railfull container load, water-rail less than container load, water-truck full container load, and water-truck less than container load. A cost optimization model for each of these transportation modes using shipping quantity as a major decision variable is developed and the associated solution procedure is provided. These models provide useful guidelines for formulating sound transportation policies. Although the evaluation framework is established based on a particular company’s global supply chain, it is applicable for many companies that are practicing global sourcing strategies.

This text proposes a mathematical programming approach to design international production-distribution networks for make-to-stock products with convergent manufacturing processes. Various formulations of the elements of... more

This text proposes a mathematical programming approach to design international production-distribution networks for make-to-stock products with convergent manufacturing processes. Various formulations of the elements of production-distribution network design models are discussed. The emphasis is put on modeling issues encountered in practice which have a significant impact on the quality of the logistics network designed. The elements discussed include the choice of an objective function, the definition of the planning horizon, the manufacturing process and product structures, the logistics network structure, demand and service requirements, facility layouts and capacity options, product flows and inventory modeling, as well as financial flows modeling. Major contributions from the literature are reviewed and a number of new formulation elements are introduced. A typical model is presented, and the use of successive mixed-integer programming to solve it with commercial solvers is discussed. A more general version of the model presented and the solution method described were implemented in a commercial supply chain design tool which is now available on the market.

Current surveys reveal that the practice of Supply Chain Management has had little impact upon business performance. This opportunity loss stands in stark contrast to the wealth of knowledge, and volumes of materials available to both... more

Current surveys reveal that the practice of Supply Chain Management has had little impact upon business performance. This opportunity loss stands in stark contrast to the wealth of knowledge, and volumes of materials available to both researchers and practitioners alike. The dissemination of Supply Chain Management theory, from its roots in Operations Research to its application in business operations, is

ABSTRACT A line balancing problem is defined by a line along which vehicles go througth and are progressivly assembled. The assembly operations are performed by workstations spread along the line. The objective is to assign operations to... more

ABSTRACT A line balancing problem is defined by a line along which vehicles go througth and are progressivly assembled. The assembly operations are performed by workstations spread along the line. The objective is to assign operations to workstations in order to minimize, for instance the number of required workstations. The basic constraints are cycle time and precedence constraints. To solve this problem, we have firstly used a genetic algorithm with different operators (some of them have been proposed in the literature). We suggest to couple this genetic algorithm with some heuristics (which have been previously published). We then obtain hybrid methods that improve the obtained offsprings, before inserting them in the population. We have tested these methods on literature instances (one range of vehicles and cycle time and precedence constraints), and on generated and industrial data. These real instances represent a real problem in the automotive industry.