On the Maintenance Modeling of a Hybrid Model with Exponential Repair Efficiency

Wassila Nissas,Soufiane Gasmi

doi:10.33889/ijmems.2021.6.1.016

Wassila Nissas, Soufiane Gasmi

Open Access

https://doi.org/10.33889/ijmems.2021.6.1.016

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Abstract

In the reliability literature, maintenance efficiency is usually dealt with as a fixed value. Since repairable systems are subject to different degrees and types of repair, it is more convenient to regard a random variable for maintenance efficiency. This paper is devoted to the statistical study of a general hybrid model for repairable systems working under imperfect maintenance. For both failure improvement and virtual age reduction of the system, maintenance efficiency is assumed to be random, with an exponential distribution as a probability density function. The likelihood function of this model is provided, and the estimation of the model parameters is computed by considering the maximization likelihood procedure. Obtained results were tested and applied to simulated and real data sets. To construct confidence intervals, the bias-corrected accelerated bootstrap method has been used.

Highlights

Modeling the maintenance efficiency on a repairable system has been widely studied in the literature, according to this efficiency, models for the failure process are classified as perfect, minimal and imperfect maintenance
The most known models for imperfect maintenance are virtual age models, which are characterized by a set of random variables {ai}i≥1 called reduction factor in the virtual age and represent the maintenance efficiency
This paper is intended for the study of a general hybrid reliability model, which combines the failure rate and the virtual age classes

Summary

Introduction

Modeling the maintenance efficiency on a repairable system has been widely studied in the literature, according to this efficiency, models for the failure process are classified as perfect, minimal and imperfect maintenance. Kijima proposed and discussed Kijima’s type 1 and type 2 models (Kijima et al, 1988; Kijima, 1989), which are both practical in different kinds of system and maintenance activities. Another known class of imperfect maintenance model are the failure rate models. This work considers known parameters for the failure intensity of systems, which is not necessarily the case in practice, statistical studies are needed to estimate the model parameters. This paper is intended for the study of a general hybrid reliability model, which combines the failure rate and the virtual age classes. The discussed model considers the random feature for maintenance efficiency

Imperfect Repair Model

Conclusion