Title: Two-machine flowshop scheduling with fuzzy processing times and flexible operations

Authors: Zeynep Uruk; Ayten Yılmaz Yalçıner

Addresses: Department of Industrial Engineering, Sakarya University, Sakarya, Turkey ' Department of Industrial Engineering, Sakarya University, Sakarya, Turkey

Abstract: This paper considers a two-machine flowshop scheduling problem with fuzzy processing times and flexible operations to minimise makespan. The jobs have three operations, one of which is a flexible operation that can be processed on one of the machines. The flexible operation should be assigned to one of the machines. Moreover, the processing times on the machines are not fixed but fuzzy processing times which are assumed to have triangular possibility distributions. Firstly, a possibilistic mathematical model is proposed with fuzzy processing times and then it is converted to an auxiliary crisp model using the weighted average defuzzification method. For the large cases where the exact algorithm may not be efficient, a heuristic algorithm is proposed. [Received: 24 May 2022; Accepted: 18 October 2022]

Keywords: scheduling; flowshop; makespan; fuzzy processing times; flexible operations.

DOI: 10.1504/EJIE.2024.135387

European Journal of Industrial Engineering, 2024 Vol.18 No.1, pp.100 - 119

Received: 24 May 2022
Accepted: 18 Oct 2022
Published online: 08 Dec 2023 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article