Mathematical modeling and solution development for “dynamic facility layout problem” in job shop process using meta-heuristic algorithms

Cost reducing is one of the main strategies for a manufacturing plant to able to survive in market competitions. Large amount of production operation costs refer to material handling costs which can be decreased with a suitable layout for the equipment. Under these conditions, dynamic facility layout problem (DFLP) for the finding of equipment site in manufacturing environment based on multi period planning horizon is raised. In this paper, DFLP for the case of job shop process is investigated. Among machines (or departments) transportation costs and rearranging costs changes from one period to another one. The other new hypothesis which adds to the problem is considering time value of money. Regarding these conditions, a new mathematical model for the problem is suggested. Since the type of the problem is a NP-hard one, for solving it two meta-heuristic algorithms - a simulated annealing(SA) and a tabu search(TS) one - are suggested. The computational results of the study show that tabu search algorithm is better for the problem of this study.