A New Heuristic for Minimal Makespan in No-Wait Hybrid Flowshops

The no-wait hybrid flowshop scheduling problem is studied to minimize the makespan. This class of problem is characterized by the processing of n jobs through m stages with one or more machines at each stage, and there is no-wait restriction between stages. An integer programming model is first formulated. Then the complete scheduling scheme for a given job sequence is built, and a new heuristic based on the scheduling scheme is proposed. Computational experience demonstrates the effectiveness of the heuristic algorithm in finding near optimal schedules.