In view of the difficulty of obtaining the optimal solution to the multi-objective scheduling of flexible job-shop by the general genetic algorithm, this paper takes into account the shortest processing time and the balanced use of machines, and puts forward the multi-population genetic algorithm based on the multi-objective scheduling of flexible job-shop. The method attempts to minimize the l...

Batch and setup times are two important factors in practical job shop scheduling. This paper proposes a method to model job shop scheduling problems including batches and anticipatory sequence-dependent setup times by timed Petri nets. The general modeling method is formally presented. The free choice property of the model is proved. A case study extracted from practical scheduling is given to ...

Flexible job shop scheduling problem (FJSP) is an extended traditional job shop scheduling problem, which more approximates to real scheduling problems. This paper presents a multi-objective genetic algorithm (GA) based on immune and entropy principle to solve the multi-objective FJSP. In this improved multi-objective GA, the immune and entropy principle is used to keep the diversity of individ...

Scheduling is a scientific domain concerning the allocation of limited tasks over time. The goal of scheduling is to maximize (or minimize) different criteria of a facility as makespan, occupation rate of a machine, total tardiness ... In this area, scientific community usually group the problem with, on one hand the system studied, defining the number of machines (one machine, parallel machine...

This paper reports an ongoing project of applying CSP algorithms CDGT and CDBT to solving job shop scheduling problems with non-relaxable time windows. A simpliied job shop scheduling task is presented to illustrate the procedure where the given task is converted into a CSP and the synthesis algorithm CDGT is combined with the search algorithm CDBT to nd a feasible or the optimal schedule. The ...

In this paper, we propose 260 scheduling problems whose size is greater than that of the rare examples published. Such sizes correspond to real dimensions of industrial problems. The types of problems that we propose are : the permutation flow shop, the job shop and the open shop scheduling problems. We restrict us to basic problems : the processing times are fixed, there are neither set-up tim...

This paper reviews modern genetic algorithm based approaches for solving job shop scheduling problems Genetic algorithms represent one of the most popular and mostly used metaheuristic methods applied for solving many optimization problems within last few decades. Job shop scheduling represents one of the hardest combinatorial optimization problems where number of possible schedules drastically...

This paper deals with scheduling of tasks in cyclic flexible job shop scheduling problem (CFJSSP). We have proposed a new method of computing cyclic time for CFJSSP. This method is based on the known properties of the job shop problem as well as new properties of cyclic scheduling. We have developed two versions of proposed method: sequential and parallel. The parallel version is dedicated to t...

This paper discusses the scheduling of precedence-related jobs non-preemptively in a job shop environment with an objective of minimizing the makespan. Due to the NP-hard nature of the scheduling problems, it is usually difficult to find an exact optimal schedule and hence one should rely on finding a near to optimal solution. This paper proposes a computationally effective powers-of-two heuris...