ANALYSIS OF THE IMPACT OF THE POSSIBILITY OF SETUP CROSSOVER ON THE LOT SIZING PROBLEM

Abstract

The lot sizing problem consists of determining the quantity of products to be produced in each period of a finite time horizon, in order to meet the demand and optimize an objective function, for example, to minimize costs. With the natural evolution of the industrial decisions making process due, among others factors, the strong competition imposed by the globalized market, different strategies have been used to improve the decisions, making them more complex. Among these strategies, recently it has appeared studies which consider that some data, although deterministic, have certain flexibility, making the problem similar to what happens in practice. This project is in line with this trend of the evolution of the decision process. Despite the relevance, there are few works that make a detailed study about adding flexibility in lot sizing problems. Note that in the supply chain literature, for example, it has been shown that adding flexibility on the production process can provide good results. In this project, we intend to study the setup flexibility. We consider an extension of the standard problem in which any period of the planning horizon starts with the setup to produce the first item to be produced in the period. In several practical applications it is possible to start a period with production (setup carryover) or to finish a setup that was started in the previous period (setup crossover). This provides more flexibility in planning and increases the possibility of finding more feasible and better solutions compared to the standard assumption.