Proper scheduling of tasks leads to optimum using of time and resources, in order to obtaining best result. One of the most important and complicated scheduling problems is open shop scheduling problem. There are n jobs in open shop scheduling problem which should be processed by m machines. Purpose of scheduling open shop problem is attaining to a suitable order of processing jobs by specified...

This paper considers a flowshop scheduling problem of a manufacturing cell that contains families of jobs whose setup times are dependent on the manufacturing ............ sequence of the families. Two objectives, namely the makespan and total flow time, have been considered simultaneously in this work. Since minimization of each of these two objectives is an NpHard problem, a Multi-Objective G...

In the present work, an industrial case study has been considered for multi-objective flow shop scheduling problem including the sequence dependent set up time. The multi-objectives include the minimization of sum of total weighted squared tardiness, total weighted squared earliness, makespan and number of tardy jobs. Industries can select the optimal sequence with respect to required objective...

The flexible flow-shop group scheduling problem is investigated in this paper to minimize the makespan. Two algorithms have been proposed to solve the problem with two machine centers, which have the same number of parallel machines. The first one is a heuristic algorithm. It first determines the sequence of jobs in each group by Sriskandarajah and Sethi’s approach of solving the flexible flow-...

In this paper we confront the job shop scheduling problem with total flow time minimization. We start extending the disjunctive graph model used for makespan minimization to represent the version of the problem with total flow time minimization. Using this representation, we adapt local search neighborhood structures originally defined for makespan minimization. The proposed neighborhood struct...

We consider the NP-hard problem of scheduling n jobs in m two-stage parallel flow shops so as to minimize the makespan. This problem decomposes into two subproblems: assigning the jobs to parallel flow shops; and scheduling the jobs assigned to the same flow shop by use of Johnson’s rule. For m = 2, we present a 32 -approximation algorithm, and for m = 3, we present a 12 7 -approximation algori...

Flexible job shop scheduling problem (FJSP) is an important extension of the classical job shop scheduling problem, where the same operation could be processed on more than one machine. A Variable Neighborhood Genetic Algorithm (VNGA) is proposed for the problem with makespan criterion, consisting of a combination of the variable neighborhood search (VNS) and genetic algorithm (GA). Variable ne...

Proper scheduling of tasks leads to optimum using of time and resources, in order to obtaining best result. One of the most important and complicated scheduling problems is open shop scheduling problem. There are n jobs in open shop scheduling problem which should be processed by m machines. Purpose of scheduling open shop problem is attaining to a suitable order of processing jobs by specified...

The job shop problem is among the class of NPhard combinatorial problems. This Research paper addresses the problem of static job shop scheduling on the job-based representation and the rule based representations. The popular search techniques like the genetic algorithm and simulated annealing are used for the determination of the objectives like minimizations of the makespan time and mean flow...