MODELING AND MIP-HEURISTICS FOR THE GENERAL LOTSIZING AND SCHEDULING PROBLEM WITH PROCESS CONFIGURATION SELECTION

In some industrial contexts, such as in the molded pulp, paper, furniture and electro fused grain industries, items or final products are obtained by processes that can produce several types of simultaneously. These considered here any specific mode operation configuration a production system different simultaneously varied quantities. The planning scheduling these contexts involve decisions of: i) selection processes; ii) lot sizing selected configurations; iii) configurations. this work, mixed integer programming model (MIP) is presented to adequately represent integrated problem, called general problem with process selection. order achieve effective plans at acceptable computational times practice, Relax-and-Fix Fix-and-Optimize heuristics based on also presented. Computational experiments were performed solving an optimization solver applying proposed examples inspired packaging companies. results show MIP-heuristics solve more effectively (good quality solution time) than simply using for mathematical model.