A Multi-Objective Approach to Optimize a Periodic Maintenance Policy

The present paper proposes a multi-objective approach to find an optimal periodic maintenance policy for a repairable and stochastically deteriorating multi-component system over a finite time horizon. The tackled problem concerns the determination of the system elements to replace at each scheduled and periodical inspections ensuring the simultaneous minimization of both the expected total maintenance cost and the expected global system unavailability time. It is assumed that the failed system elements are repaired by means of minimal repair actions in order to rapidly restore the system. A non-linear integer mathematical programming model is developed to solve the treated multi-objective problem while the Pareto optimal frontier is described by the Lexicographic Goal Programming and the epsilon-constraint methods. To explain the whole procedure a numerical application related to a case study is given.