The bi-objective stochastic covering tour problem

Comput Oper Res. 2012 Jul;39(7):1582-1592. doi: 10.1016/j.cor.2011.09.009.

Abstract

We formulate a bi-objective covering tour model with stochastic demand where the two objectives are given by (i) cost (opening cost for distribution centers plus routing cost for a fleet of vehicles) and (ii) expected uncovered demand. In the model, it is assumed that depending on the distance, a certain percentage of clients go from their homes to the nearest distribution center. An application in humanitarian logistics is envisaged. For the computational solution of the resulting bi-objective two-stage stochastic program with recourse, a branch-and-cut technique, applied to a sample-average version of the problem obtained from a fixed random sample of demand vectors, is used within an epsilon-constraint algorithm. Computational results on real-world data for rural communities in Senegal show the viability of the approach.

Keywords: Branch-and-cut; Covering tour problem; Disaster relief; Multi-objective optimization; Stochastic optimization.