Simulated annealing based robust algorithm for routing-scheduling problem with uncertain execution times

Abstract

A routing-scheduling problem treated as a generalization of a traditional task scheduling problem is investigated in the paper. The generalization deals with the necessity to drive-up of executors, being the performers of tasks, to workstations where the tasks are carried out. An uncertain version of a simple problem with the makespan as the performance index is considered. It is assumed that execution times are not known a priori, but they are elements of given intervals. The uncertain decision-making problem is formulated with the performance index being the absolute regret based on the makespan. A heuristic solution algorithm, which uses a simulated annealing metaheurisics, is proposed. The property of the performance index is shown, which makes easier its calculations. Selected results of numerical experiments are given which evaluate the quality of the uncertain problem in terms of the absolute regret and the time of computation.