Reactive grasp and tabu search based heuristics for the single source capacitated plant location problem

This paper considers the Single Source Capacitated Plant Location Problem (SSCPLP). SSCPLP is a discrete location problem. It allows capacities on the plants to be opened and constrains each client to be served by a single open plant. The following algorithms are proposed: A Reactive GRASP heuristic; a Tabu Search heuristic; and two different hybrid approaches that combine elements of the GRASP and the Tabu Search methodologies. The elements of the proposed heuristics are presented. The Reactive GRASP algorithm is a self-tuning heuristic in which the calibration process is replaced by an automated criterion for selecting the parameter value. The Tabu Search heuristic provides the framework for the first of the hybrid approaches. It consists of two phases. The GRASP methodology is used for the first one, which can be viewed as a strong diversification mechanism. The second one consists of an intensification phase. The second hybrid algorithm follows the framework of the Reactive GRASP heuristic. It also consists of two phases and Tabu Search is used in the second phase as a mechanism to strengthen the Local Search. Computational experiments have been performed to evaluate the behavior of the proposed methods. The results on two different sets of test problems show that the proposed methods are very efficient. In particular, all of them outperform previous heuristic approaches in small computation times. Moreover, the outcome of different series of experiments carried out with CPLEX confirms the quality of all the heuristics and, in particular, of the two hybrid approaches.