Hybrid ant systems for the dynamic facility layout problem

Today's consumer market demands that manufacturers must be competitive. This requires the efficient operation of manufacturing plants and their ability to quickly respond to changes in product mix and demand. In addition, studies show that material-handling cost make up between 20 and 50 percent of the total operating cost. Therefore, this paper considers the problem of arranging and rearranging, when there are changes in product mix and demand, manufacturing facilities such that the sum of material handling and rearrangement costs is minimized. This problem is called the dynamic facility layout problem (DFLP). In this paper, hybrid ant systems (HASs) are developed to solve the DFLP. To test the performance of the meta-heuristics, two data sets taken from the literature are used in the analysis. The results show that the HASs are efficient techniques for solving the DFLP. More importantly, HASs found new best solutions for more than one-half of all the test problems. (c) 2004 Elsevier Ltd. All rights reserved.