We consider in this paper the two-machine no-wait flowshop scheduling problem in which each machine may have an unavailable interval. We present a polynomial time approximation scheme for the problem when the unavailable interval is imposed on only one machine, or the unavailable intervals on the two machines overlap.

Minimizing the total completion time (TCT) is essential in numerous manufacturing settings. Since such a problem considered NP-hard, it not likely that an optimal solution exists. Accordingly, many papers scheduling literature look for dominance relation as to minimizing TCT. Furthermore, due wide range of unpredictability settings, consider settings with uncertain and bounded setup times. None...

We introduce a new technique for solving several sequencing problems. We consider Gilmore and Gomory’s variant of the Traveling Salesman Problem and two variants of no-wait flowshop scheduling, the classical makespan minimization problem and a new problem arising in the multistage production process in steel manufacturing. Our technique is based on an intuitive interpretation of sequencing prob...

this article addresses a multi-stage flowshop scheduling problem with equal number of unrelated parallel machines. the objective is to minimize the makespan for a given set of jobs in the system. this problem class is np-hard in the strong sense, so a hybrid heuristic method for sequencing and then allocating operations of jobs to machines is developed. a number of test problems are randomly ge...

This paper considers a no-wait multi product flowshop scheduling problem with sequence dependent setup times. Lot streaming divide the lots of products into portions called sublots in order to reduce the lead times and work-in-process, and increase the machine utilization rates. The objective is to minimize the makespan. To clarify the system, mathematical model of the problem is presented. Sin...

The two-stage assembly flowshop scheduling problem is addressed with the objective of minimizing total tardiness. An insertion algorithm, a genetic algorithm, and a hybrid of the insertion and genetic algorithms, are developed for the problem. Conducted computational experiments reveal that the hybrid algorithm significantly outperforms the genetic algorithm while the best performing algorithm ...