Aven, T.

replacement model framework cycle failure function system block replacement model opportunity decision condition cycle length block result dekker policy section maintenance repair length age t analysis european journal probability research cost criterion time t cost analysis maintenance models renewal age replacement model component approach criterion journal theorem theorem 1 research logistics process optimization optimality assumption paper interval european example value cost approach replacement models change section 2 notice cost interpretation nonhomogeneous poisson process survival control set-up number formula logistic preventively interpretation structure replacement times hazard application replacement policies non-increasing elsevier reliability condition b procedure problem limit equation action poisson survey q /ex cost rate