The bi-objective covering tour problem

The paper discusses the definition and solution of a bi-objective routing problem, namely the bi-objective covering tour problem. The bi-objective CTP is a generalization of the covering tour problem, which means that the covering distance and the associated constraints have been replaced by a new objective. We propose a two-phase cooperative strategy that combines a multi-objective evolutionary algorithm with a branch-and-cut algorithm initially designed to solve a single-objective covering tour problem. Experiments were conducted using both randomly generated instances and real data. Optimal Pareto sets were determined using a bi-objective exact method based on an epsilon-constraint approach with a branch-and-cut algorithm. (c) 2005 Elsevier Ltd. All rights reserved.