GRASP and VNS for solving the p-next center problem

Abstract

This paper presents two metaheuristic algorithms for the solution of the p-next center problem: a Greedy Randomized Adaptive Search Procedure and a Variable Neighborhood Search algorithm, that will be sub- sequently hybridized. The p -next center problem is a variation of the p-center problem, which consists of locating p out of n centers and assigning them to users in order to minimize the maximum, over all users, of the distance of each user to its corresponding center plus the distance between this center to its closest alternative center. This problem emerges from the need to reach a secondary help center in the case of a natural disaster, when the closest center may become unavailable.