Comparison of two-lifetime models of solid-state lighting based on sup-entropy
1Natural Sciences, Mathematics and Technology Unit, Effat University, Jeddah, 21478, Saudi Arabia.
Heliyon
|October 25, 2019
Summary
This study compares lognormal and Weibull distributions for modeling solid-state lighting luminaire lifetime. The Weibull distribution demonstrated superior performance in estimating mean time to failure.
Area of Science:
- Engineering
- Statistics
- Materials Science
Background:
- Solid-state lighting (SSL) luminaire lifetime is critical for system reliability and maintenance planning.
- Accurate lifetime modeling is essential for predicting SSL performance and ensuring long-term viability.
- Existing models may not fully capture the complexities of SSL degradation and failure patterns.
Purpose of the Study:
- To compare the performance of lognormal and Weibull distributions in modeling censored solid-state lighting luminaire lifetime data.
- To evaluate the efficacy of the Kittaneh and Beltagy efficiency function for assessing model fit.
- To determine the most accurate distribution for estimating the mean time to fail for SSL luminaires.
Main Methods:
- Utilized censored samples from lognormal and Weibull distributions.
- Applied the Kittaneh and Beltagy efficiency function to compare model performance.
- Correlated model accuracy with the estimation of mean lifetime to fail.
Main Results:
- The Weibull distribution generally outperformed the lognormal distribution in fitting censored SSL luminaire lifetime data.
- The Kittaneh and Beltagy efficiency function showed strong correlations with the accuracy of mean lifetime estimations.
- The study validated the utility of the efficiency function in selecting appropriate lifetime models.
Conclusions:
- The Weibull distribution is a more suitable model than the lognormal distribution for censored solid-state lighting luminaire lifetime data.
- The Kittaneh and Beltagy efficiency function is a valid and useful tool for evaluating lifetime model performance.
- Accurate lifetime modeling is crucial for optimizing the design and deployment of SSL systems.
Keywords:
Applied mathematicsCensored sampleEntropyLognormal distributionMean lifetimeSSL luminaireSup-entropyWeibull distributionMore Related Videos
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