age replacement model of a used system

As there are various replacement policies for maintaining and improving operating and non-operating systems, this paper investigated the properties of an age replacement model of a used series system of a certain age. the system is subjected to two types of failures: type i and type ii. it is assumed that, type i failure is a repairable one, while type ii failure is a non-repairable one. an analytical expression of the expected cost rate for a used series system with n components was obtained. a simple illustrative numerical example was made available to analyze the effectiveness and properties of the constructed replacement model.