Flow shop scheduling for separation model of set-up and net process based on Branch-and-Bound method

Lots of research reports on flow shop scheduling problems have been reported. Generally speaking, these models are applicable to a simple model with no separation of set-up processes and net ones. In many production lines, we cannot ignore the set-up times in comparison with the net processing times. We can expect to shorten the total processing time by executing the set-up processes and net ones in parallel. We need a parallel operation model to improve schedule results. We will propose a new scheduling method for multi-stage flow shops. The aim of the method is to shorten the total processing time by operating the set-up processes and the net ones of each job in parallel. We applied the Branch-and- Bound method and developed a new calculation algorithm for the lower bound estimation of the total processing time. Finally, we will evaluate our proposed method by some numerical experiments using actual production line data. 2008 Elsevier Ltd. All rights reserved.