An immune-based algorithm for the multi-maintenance with sequential operations

Abstract

In this study, we investigate a new multi-maintenance with sequential operation (MMSO) problem, in which a variety of tasks must be processed on multiple machines. In the MMSO problem, each task has multiple sequential operations that must be processed for each machine. In addition to maintenance, the MMSO problem has many other practical applications, such as physical examination scheduling. The proposed MMSO, which is an NP-hard problem, generalizes typical job shop scheduling problems. Thus, a novel encoding scheme, which is embedded into an immune-based algorithm (IBA), is proposed in this study to convert any sequence of random numbers into a feasible solution of the MMSO problem to solve the MMSO problem. Numerical results of applications in aircraft maintenance and physical examination scheduling are reported and compared with those of particle swarm optimization and genetic algorithm. Experimental results show that IBA outperforms the two other algorithms.