Mixed Integer Programming Approaches to Planning and Scheduling in Electronics Supply Chains

This paper discusses mixed-integer programming (MIP) approaches to planning and scheduling in electronics supply chains. First, the short-term detailed scheduling of wafer fabrication in semiconductor manufacturing and detailed scheduling of printed wiring board assembly in surface mount technology lines are discussed. Then, the medium-term aggregate production planning in a production/assembly facility of a consumer electronics supply chain is described; and finally, the coordinated aggregate planning and scheduling of the manufacturing and supply of parts and production of the finished products is presented. The decision variables are defined, and the MIP modeling frameworks are provided. Two decisionmaking approaches are discussed and compared: an integrated (simultaneous) approach, in which all required decisions are made simultaneously using a complex, large monolithic MIP model; and a hierarchical (sequential) approach, in which the required decisions are made successively using the hierarchies of simpler and smaller-sized MIP models. The paper also highlights the research on stochastic MIP applications to the planning and scheduling in electronics supply chains with disrupted material and information flows due to natural or man-made disasters.