In this paper, scheduling problems in Flexible Manufacturing Cells (FMC) are studied. The scheduling objective is to minimize the makespan. We used a genetic algorithm (GA) for solving the optimization scheduling problem. We have developed one FMC with industrial characteristics with the objective of studying scheduling problems in these types of manufacturing systems (single machine scheduling...

We consider several combinatorial optimization problems which combine the classic shop scheduling problems, namely open shop scheduling or job shop scheduling, and the shortest path problem. The objective of the obtained problem is to select a subset of jobs that forms a feasible solution of the shortest path problem, and to execute the selected jobs on the open (or job) shop machines to minimi...

This paper presents a state of the art overview on Ants Systems. Initially the work proposes the fundamental concepts of Ants Theory and offers a description of the main algorithms (based on Ants Theory) and the respective fields of application. Among different fields of application, the paper focuses on industrial plants scheduling problems in open shop, flow shop and job shop systems. The las...

production planning is performed through diverse methods according to the type of the system it is structured upon. one of the most important steps before production planning is to determine which system best fits the firm, and how the facilities should be designed. both job-shop and group-technology systems have their own cons and pros, each of which is suitable to a specific kind of factory. ...

Job Shop Scheduling is an important combinatorial optimisation problem in practice. It usually contains many (four or more) potentially conflicting objectives such as makespan and mean weighted tardiness. On the other hand, evolving dispatching rules using genetic programming has demonstrated to be a promising approach to solving job shop scheduling due to its flexibility and scalability. In th...

Typically, general job shop scheduling problems assume that working times of machines are equal, for instance eight hours a day. However, in real factories, these working times are different because the machines may have different processing speeds, or they may require maintenance. That is, one machine may need to be operated only half day whereas other machines may have to be operated for the ...

We consider a general class of multiprocessor shop scheduling problems, preemptive or nonpreemptive, with precedence constraints between operations, with job or operation release dates, and with a class of objective functions including weighted sums of job, operations and stage completion times. We present a general approximation method combining a linear programming relaxation in the operation...

This paper deals with the Job Shop scheduling problem with constraints of minimum and maximum Time Lags (JSTL). This problem is an extension of the job shop scheduling problem, with additional constraints of minimum and maximum time lags existing between successive operations of the same job. In this work, we investigate Parallel Tabu Searches implemented by competitive agents for the Job Shop ...

Examination of the job-shop scheduling literature uncovers a striking trend. As methods for the deterministic job-shop problem have gradually improved over the years, they have come to rely on neighbourhoods for selecting moves that are more and more constrained. We document this phenomenon with a historical sketch of job-shop neighborhoods, which leads us to focus particularly on the approach ...

A Job-Shop Scheduling is a process–organized manufacturing facility. Its main characteristics are that a great diversity of jobs is performed. A Job-Shop produces goods (parts) and these parts have one or more alternatives process plans. Each process plan consists of a sequence of a operations and these operations require resources and have certain (predefined) duration on machines. The Job-Sho...