Two-Machine Flowshop Scheduling with Consecutive Availability Constraints

In this paper we study a special case of the two-machine flowshop problem with an availability constraint imposed on each machine. The two availability constraints are consecutive. We establish some basic properties for the semiresumable case, i.e. if a job cannot be finished before the next down period of a machine, then the job will be partially restarted when the machine becomes available again. We provide a heuristic for the problem and show that it has a worst-case error bound of 2/3 for the nonresumable case.