# Reliability Analysis of Random Fuzzy Repairable Series System

• Ying Liu
• Xiaozhong Li
• Guanglei Yang
Conference paper
Part of the Advances in Intelligent and Soft Computing book series (AINSC, volume 78)

## Abstract

Usually, the lifetimes and repair times of series systems are assumed to be random variables. The probability distributions of the random variables have crisp parameters. In many practical situations, the parameters are difficult to determine due to uncertainties and imprecision of data. So it is appropriate to assume the parameters to be fuzzy variables. In this paper, the lifetimes and repair times of components are assumed to have random fuzzy exponential distributions, then the limiting availability, steady state failure frequency, mean time between failures (MTBF), mean time to repair (MTTR) of the repairable series system are proposed. Finally, a numerical example is presented.

## Keywords

Limiting availability steady state failure frequency mean time between failures mean time to repair series system random fuzzy variable

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