This paper studies no-wait flowshop scheduling problems to minimize total tardiness. This paper mathematically formulates the problem as an effective mixed integer linear programming model. Moreover, this paper proposes solution methods based on variable neighborhood search and simulated annealing algorithms. Besides, some well-known heuristics of classical flow shops are adapted to the case of...

This paper studies the problem of scheduling N jobs in a hybrid flowshop with unrelated parallel machines at each stage. Considering practical application presented problem, no-wait constraints and objective function total flowtime are included problem. A mathematical model is constructed novel genetic simulated annealing algorithm so-called GSAA developed to solve this In algorithm, firstly mo...

This paper studies the two-machine flowshop scheduling problem with class setups in a no-wait processing environment to minimize the maximum lateness. The jobs are divided into job classes and a setup is required at the initial processing of a job or between the processing of jobs of different classes. In a no-wait environment, a job must be processed from start to finish without interruptions ...

Flowshop scheduling problems have been extensively studied by several authors using different approaches. A typical flowshop process consists of successive manufacturing stages arranged in a single production line where different jobs have to be processed following a predefined production recipe. In this work, the scheduling of a complex flowshop process involving automated wet-etch station fro...

We consider a variant of no-wait flowshop scheduling that is motivated by continuous casting in the multistage production process in steel manufacturing. The task is to find a feasible schedule with a minimum number of interruptions, i.e., continuous idle time intervals on the last production stage. Based on an interpretation as Eulerian Extension Problems, we fully settle the complexity status...

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...

We address the no-wait k-stage flexible flowshop scheduling problem where there are m identical machines at each stage. The objectives are to schedule the available n jobs so that makespan and mean tardiness of n jobs are minimized. Sequence-dependent setup times are treated in this problem as one of the prominent practical assumptions. This problem is NP-hard, and therefore we present a new mu...

In this work we study a flowshop scheduling problem in which jobs are not allowed to wait in-between machines, a situation commonly referred to as no-wait. The concerned criterion is to minimize a weighted sum of makespan and maximum lateness. A dominance relation for the case of three-machine is presented and evaluated by experimental designs. Several heuristics and local search methods are pr...

We consider in this paper the two-machine no-wait flowshop problem in which each machine may have an unavailable interval. We present 3 2 -approximation algorithms for the problem when the unavailable interval is imposed on only one machine, or the unavailable intervals on the two machines overlap. These algorithms improve on existing results.