Parameter interval estimation of system reliability for repairable multistate series-parallel system with fuzzy data.
Wimonmas Bamrungsetthapong1, Adisak Pongpullponsak1
1Department of Mathematics, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand.
Thescientificworldjournal
|July 3, 2014
Summary
This study develops a fuzzy confidence interval for the reliability of repairable multistate series-parallel systems (RMSS). The method provides a reliable interval estimation for system reliability, especially with larger sample sizes.
Area of Science:
- Reliability Engineering
- Fuzzy Set Theory
- System Analysis
Background:
- Assessing the reliability of complex systems like repairable multistate series-parallel systems (RMSS) is challenging due to inherent uncertainties.
- Traditional reliability estimation methods may not adequately capture the vagueness associated with system parameters such as failure and repair rates.
Purpose of the Study:
- To construct a two-sided fuzzy confidence interval for the reliability of RMSS.
- To evaluate the performance of the fuzzy confidence interval based on coverage probability and expected length.
- To apply fuzzy set theory to address uncertainties in RMSS reliability estimation.
Main Methods:
- Utilized fuzzy set theory to model system reliability under uncertainty.
- Employed fuzzy numbers with triangular membership functions for fuzzy failure and repair rates.
- Developed a method for interval estimation of fuzzy system reliability for RMSS.
Main Results:
- The proposed fuzzy confidence interval demonstrates effective performance, characterized by good coverage probabilities and narrow expected lengths.
- The interval estimator is particularly effective for sample sizes greater than or equal to 100.
- Optimal alpha-cuts were identified to minimize both lower and upper expected lengths of the confidence interval.
Conclusions:
- The presented fuzzy interval estimation method is effective for assessing the reliability of RMSS with uncertain parameters.
- The approach provides a valuable tool for reliability engineers dealing with complex, repairable systems.
- Further investigation into optimal alpha-cuts can refine the precision of reliability estimations.
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