K-Center Location

Let V be the set of nodes of a complete undirected graph of n nodes with edge weights cij ≥ 0 associated with edge (i,j) for all nodes i, j in V; and cii = 0. Given an integer k, l ≤ k ≤ n, the k-center location problem is to find a subset S of V of size at most k such that $$ Z = \mathop{{\max }}\limits_{{i \in V}} {\mkern 1mu} \mathop{{\min }}\limits_{{j \in S}} {\mkern 1mu} {{c}_{{ij}}} $$ is minimized.