The optimal number of used machines in a two-stage flexible flowshop scheduling problem

作者：Gerstl Enrique; Mosheiov Gur^*

来源：Journal of Scheduling, 2014, 17(2): 199-210.

DOI：10.1007/s10951-013-0343-z

• Scheduling
• Sequencing
• Deterministic
• Flowshop
• Makespan
• Flowtime

We study practical scheduling problems with a major decision referring to the number of machines to be used. We focus on a two-stage flexible flowshop, where each job is processed on the first (critical) machine, and then continues to one of the second-stage parallel machines. Jobs are assumed to have identical processing times, and are processed in batches. A setup time is required when starting a new batch. We consider two objective functions: minimum makespan and minimum flowtime. In both cases, a closed form expression for the optimal number of machines to be used is introduced, and a unique and unusual sequence of decreasing batch sizes is shown to be optimal.

• 出版日期2014-4