A new hybrid flow shop scheduling problem with blocking is studied. The problem is characterized by multistage unrelated parallel machines and no intermediate buffer. Firstly, the math model of the hybrid scheduling problem is constructed. And then the computation method of production period is given. Due to there is no intermediate buffer, and there are unrelated parallel machines in multi-sta...

We focus on the two-center hybrid flow shop scheduling problem with identical parallel machines and removal times. The job removal time is the required duration to remove it from a machine after its processing. The objective is to minimize the maximum completion time (makespan). A heuristic and a lower bound are proposed for this NP-Hard problem. These procedures are based on the optimal soluti...

Parallel machine scheduling problems concern the scheduling of n jobs on m machines to minimize some function of the job completion times. If preemption is not allowed, then most problems are not only NP-hard, but also very hard from a practical point of view. In this paper, we show that strong and fast linear programming lower bounds can be computed for an important class of machine scheduling...

In many practical manufacturing environments, setups consume a significant amount of industrial resources. Therefore, reducing setups in a non-identical parallel machine environment will significantly enhance a company’s performance level. In this thesis, the problem of minimizing total completion time with load balancing and sequence-dependent setups in a non-identical parallel machine environ...

in this paper, a multi-product single machine scheduling problem with the possibility of producing defected jobs, is considered. we concern rework in the scheduling environment and propose a mixed-integer programming (mip) model for the problem.  based on the philosophy of just-in-time production, minimization of the sum of earliness and tardiness costs is taken into account as the objective fu...

we study the nonpreemptive parallel machines scheduling problem where some of the machines are planned to be shutdown. We apply LPT algorithm to the problem and analyze its performance. Our analysis shows that the makespan of the LPT schedule is bounded by twice the optimum makespan if no more than half of the machines are allowed to be shutdown simultaneously. We also show that this bound ls t...