General Efficiency Modeling with Planned Preventive Maintenance

We propose in this article, a general model of the joint effect of corrective and preventive maintenance for repairable systems in degradation. The assessing criterion of the maintenance efficiency is supported with the failure intensity in the bath-tub form. The maintenance effect is expressed by the change induced on the failure intensity before and after maintenance. The modeling frameworks are proposed and studied in order to generalize several models to the planned preventive maintenances. The generalization of the models suggested makes it possible to integrate the dependence between corrective and preventive maintenances. The likelihood functions are derived, so parameter estimation and assessment of the maintenance efficiency are possible. Relevant results relating to the theoretical properties of the maintenance efficiency estimators allow to better understand the system behavior. Finally, results are illustrated on a basis of real data issued from industry.