Rescheduling on Unrelated Parallel Machines with Rush Order

In a production system, the stability of a production schedule may be affected if the associated order is changed. Rescheduling methods are usually adopted to reduce the impacts caused by the job sequence changes. In the past decades, rescheduling attracts lots of attentions, and most of the existing studies focus on the optimization of production efficiency (for example, makespan and tardiness) rather than the production stability after rescheduling. In this paper, an event-driven complete rescheduling strategy is proposed in consideration of rush order insertion to a hybrid multi-machine production system. The impact of rush order is considered as a deviation cost and merged into the total cost when optimizing rescheduling. Genetic algorithm is adopted to optimize the rescheduling with the objective of minimizing the total cost. The effectiveness of this paper is demonstrated by a numeric example and the comparison with the baseline scheduling strategy and right-shift rescheduling strategy.