Title
Genetic tabu search for the fuzzy flexible job shop problem.
Abstract
This paper tackles the flexible job-shop scheduling problem with uncertain processing times. The uncertainty in processing times is represented by means of fuzzy numbers, hence the name fuzzy flexible job-shop scheduling. We propose an effective genetic algorithm hybridised with tabu search and heuristic seeding to minimise the total time needed to complete all jobs, known as makespan. To build a high-quality and diverse set of initial solutions we introduce a heuristic method which benefits from the flexible nature of the problem. This initial population will be the starting point for the genetic algorithm, which then applies tabu search to every generated chromosome. The tabu search algorithm relies on a neighbourhood structure that is proposed and analysed in this paper; in particular, some interesting properties are proved, such as feasibility and connectivity. Additionally, we incorporate a filtering mechanism to reduce the neighbourhood size and a method that allows to speed-up the evaluation of new chromosomes. To assess the performance of the resulting method and compare it with the state-of-the-art, we present an extensive computational study on a benchmark with 205 instances, considering both deterministic and fuzzy instances to enhance the significance of the study. The results of these experiments clearly show that not only does the hybrid algorithm benefit from the synergy among its components but it is also quite competitive with the state-of-the-art when solving both crisp and fuzzy instances, providing new best-known solutions for a number of these test instances.
Year
DOI
Venue
2015
10.1016/j.cor.2014.08.023
Computers & Operations Research
Keywords
Field
DocType
Genetic algorithms,Neighbourhood structure,Local search,Heuristics,Flexible job shop scheduling,Fuzzy processing times
Mathematical optimization,Job shop scheduling,Job shop,Fuzzy logic,Heuristics,Local search (optimization),Fuzzy number,Genetic algorithm,Mathematics,Tabu search
Journal
Volume
Issue
ISSN
54
C
0305-0548
Citations 
PageRank 
References 
5
0.42
0
Authors
5
Name
Order
Citations
PageRank
Juan José Palacios1596.73
Miguel A. González215312.44
Camino R. Vela334631.00
Inés González Rodríguez4726.52
Jorge Puente517113.16