Appropriate scheduling and sequencing of tasks on machines is one of the basic and significant problems that a shop or a factory manager encounters with it, this is why in recent decades extensive researches have been done on scheduling issues. A type of scheduling problems is just-in-time (JIT) scheduling and in this area, motivated by JIT manufacturing, this study investigates a mathematical ...

We show a close connection between structural hardness for k-partite graphs and tight inapproximability results for scheduling problems with precedence constraints. Assuming a natural but nontrivial generalisation of the bipartite structural hardness result of [1], we obtain a hardness of 2 − for the problem of minimising the makespan for scheduling precedence-constrained jobs with preemption o...

This paper studies a combination problem of parallel machine scheduling and the covering problem. We say a combinatorial optimization problem is a covering problem if it minimizes a linear objective function under some constraints and the variables are binary. The covering problem generalizes many classic combinatorial optimization problems, e.g. the shortest path problem, the vertex cover prob...

We consider the parallel machine scheduling problem where jobs have different earlinesstardiness penalties and a restrictive common due date. This problem is NP-hard in the strong sense. In this paper we define an exponential size neighborhood for this problem and prove that finding the local minimum in it is an NP-hard problem. The main contribution of this paper is to propose a pseudo-polynom...

This paper presents a new mixed-integer goal programming (MIGP) model for a parallel machine scheduling problem with sequence-dependent setup times and release dates under the hypothesis of fuzzy processing time’s knowledge. Two objectives are considered in the model to minimize the total weighted flow time and the total weighted tardiness simultaneously. At the end, the effectiveness of the pr...

In the literature, most of the parallel-machine scheduling problems, in which the processing time of a job is a linear function of its starting time, are proved to be NP-hard. In this paper, we study a parallel-machine scheduling problem in which the processing time of a job is a linear function of its starting time. The objectives are to minimize the total completion of all jobs and the total ...

This paper discusses a parallel machine scheduling problem in which the processing times of jobs and the release dates are independent uncertain variables with known uncertainty distributions. An uncertain programming model with multiple objectives is obtained, whose first objective is to minimize the maximum completion time or makespan, and second objective is to minimize the maximum tardiness...

This paper considers a scheduling problem of a set of independent jobs on unrelated parallel machines (UPMs) that minimizesthe maximum completion time (i.e., makespan or ), maximum earliness ( ), and maximum tardiness ( ) simultaneously. Jobs have non-identical due dates, sequence-dependent setup times and machine-dependentprocessing times. A multi-objective mixed-integer linear programmi...

This paper proposes a mixed integer programming model to solve a non-identical parallel machine (NIPM) scheduling with sequence-dependent set-up times and human resiliency engineering. The presented mathematical model is formulated to consider human factors including Learning, Teamwork and Awareness. Moreover, processing time of jobs are assumed to be non-deterministic and dependent to their st...