The job shop scheduling problem is considered NP-hard. In real applications, the processing time of each task is often imprecise. Therefore, this paper deals with the job shop scheduling problem, where the processing time of each task is modeled by triangular fuzzy numbers (NTF). The aim of the problem is to find a schedule that minimizes the fuzzy makespan. In this approach it was worked with the memetic algorithm (MA) and the algorithm of ant colony system (ACS) to solve the problem. A hybridization of these two approaches called MA-ACS(CC-MO) is proposed, and to compare the efficiency of the approach is realized a comparison between three algorithms AG-ACS, ACS-ΜΑ (MO) and MA-ACS (CC-MO), using eight of the OR-Library problems.
Fuzzy job shop scheduling problem; Ant colony system; memetic algorithm