A tabu search algorithm for the open shop scheduling problem

An approximation algorithm of finding a minimum makespan in a nonpreemptive open shop is presented. The algorithm is based on the tabu search technique with a neighborhood structure defined using blocks of operations on a critical path. An efficient procedure is also developed for evaluating a neighborhood. The algorithm is tested on 450 randomly generated problems and a set of 60 benchmarks. Computational results show that the algorithm finds extremely high-quality solutions for all of the test problems in a reasonable amount of computation time, and hence demonstrate the potential of the algorithm to efficiently schedule open shops.