METAHEURÍSTICAS COM BUSCA LOCAL PARA O PROBLEMA DE JUST-IN-TIME JOB-SHOP SCHEDULING

This article describes a combination of metaheuristcs and local search for the just-in-time job- shop scheduling problem, with earliness and tardiness penalties. In this problem, each operation of each job has a specific machine to be processed in a specific order and a process time, a due date, and earliness and tardiness costs, which will be paid if the operation ends before or after the due date. Besides the application of two metaheuristics, problem specific operators and local search methods are proposed. Finding the exact solution is hard even for small instances, but the proposed algorithm showed to be efficient when compared to results of others methods recently published on the literature. The methods were tested with instances from the literature with up to 20 jobs and 10 machines, and obtained solutions with higher quality than those already published.