Altered quasi-renewal concepts for modeling renewable warranty costs with imperfect repairs

We introduce the concepts of altered quasi-renewal based on the ordinary quasi-renewal process. The first is called the altered quasi-renewal process with random parameters and the other is called the mixed quasi-renewal process with considerations of replacement and repair strategies. Based on the proposed altered- and mixed- quasi-renewal processes, we develop the warranty cost models and also derive various reliability measures. This study can help the policy makers to make appropriate decisions related to the warranty polices with the objective of downsizing manufacturer’s warranty costs. Also, the results of this study using mixed and altered quasi-renewal processes can be found helpful for practitioners to analyze the system’s warranty cost. An application for practical and numerical examples is discussed to demonstrate the applicability of the proposed concepts.