حسن رسائی

In this paper, emphasizing the real conditions prevailing in production industries, a new optimization model is developed in order to optimally schedule preventive maintenance and repair activities in a multi-component maintainable manufacturing system addressing a novel approach. It is assumed that failures or inspections are not only causes of stopping devices but also some other activities (non-failure stops) may interrupt the production process. The presented mathematical model utilizes these interruptions as opportunities to perform some maintenance activities. Failure interaction between components is also considered and the rate of failure of each component due to shocks from other components may be increased by a certain percentage. In addition to preventive maintenance and repairs, in the case of sudden failure of any component, corrective maintenance is implemented. Besides, the cost of stopping the system for performing maintenance activities is considered dependent on the duration of maintenance execution. Due to the complexity of the structure of the proposed model, the Genetic algorithm is adapted as the solution approach and its parameters are adjusted by the Taguchi method. A numerical example is solved and analyzed. Finally, a comparison between the exact method and the developed algorithm is provided to examine its efficiency and the impacts of the rise in problem sizes on the performance of the algorithm.