Bounds for the single source modular capacitated plant location problem

In this paper, we propose a discrete location problem, which we call the Single Source Modular Capacitated Location Problem (SS-MCLP). The problem consists of finding the location and capacity of the facilities, to serve a set of customers at a minimum total cost. The demand of each customer must be satisfied by one facility only and the capacities of the open facilities must be chosen from a finite and discrete set of allowable capacities. Because the SS-MCLP is a difficult problem, a lagrangean heuristic, enhanced by tabu search or local search was developed in order to obtain good feasible solutions. When needed, the lower bounds are used in order to evaluate the quality of the feasible solutions. Our method was tested computationally on randomly generated test problems some of which are with large dimensions considering the literature related to this type of problem. The computational results obtained were compared with those provided by the commercial software Cplex.