Modelos e métodos de resolução para problemas integrados de dimensionamento de lotes de produção com decisões de distribuição e arranjo de carga

Abstract

In this research, we study lot sizing problems with decisions on product distribution and, also, problems that integrate lot sizing decisions and product packing in the vehicles (bins). In general, these problems involve a trade-off among production costs, holding costs and distribution costs. The lot sizing problems consider limitations in the production capacity and demand delivery deadline. The distribution decisions are related to the product loading into the unit load device (pallets, containers or trucks). The packing problems may involve one, two or three dimensions relevant to the product loading. The problems are modeled by mathematical programming and solved by the branch-and-cut method of an optimization package, and then, the performance and the results obtained are analyzed. Furthermore, heuristic methods are specifically developed in order to provide an approximate solution for these problems. The heuristic methods are built according to the lagrangian relaxation and ant colony optimization. All the methods are tested and evaluated, regarding the solutions found by the optimization package for the proposed models.