Improved Lower Bounds for the Proportional Lot Sizing and Scheduling Problem
نویسنده
چکیده
Where standard MIP{solvers fail to compute optimum objective function values for certain MIP{model formulations, lower bounds may be used as a point of reference for evaluating heuristics. In this paper, we compute lower bounds for the multi{level proportional lot sizing and scheduling problem with multiple machines (PLSP{MM). Four approaches are compared: Solving LP{relaxations of two di erent model formulations, solving a relaxed MIP{model formulation optimally, and solving a Lagrangean relaxation.
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تاریخ انتشار 1996