A clonal selection algorithm for dynamic facility layout problems

The dynamic facility layout problem (DFLP) aims to minimize the sum of handling and re-layout costs by devising an individual layout for each distinctive production period. It is a complex combinatorial optimization problem. This paper proposes a clonal selection algorithm (CSA) for DFLP. The algorithm is capable of being extended to more general cases although equal area machines and standardized handling equipments with identical unit costs are assumed for the time being. The performance of the proposed algorithm is examined by using three test problems from the literature. CSA reached the best known solutions–even found better solutions for large sized problems–in 88% of the instances, while each of the former methods was successful only in a small fraction of those 50 problems. CSA also outperformed all the present methods as regards solution times.