指数寿命产品的寿命性能评估

Estimation of lifetime performance exponential products

传统的统计过程控制理论假设过程的质量特性值服从正态分布,然而在实践过程中这一假设并不成立。本文假设产品的质量特性值服从指数分布,基于定数截尾样本,用过程能力指数评估产品的寿命性能,给出寿命性能指数CL的一致最小无偏估计及其置信区间,提出一种新的方法对CL进行检验。最后通过实例表明,此检验方法不仅简单易行,而且还可以用来判断产品是否达到所要求的水平。

The traditional statistical process control theory is to assume that the characteristic value of qua-lity of the process is normal distribution.However,in the practical process this hypothesis is untenable.The quality characteristic of the products is assumed to obey exponential distribution,and the process capability index is used to evaluate the lifetime performance of products based on the type II right-censored sample.This study constructs a uniformly minimum variance unbiased estimator（UMVUE）,and the confidence interval of the lifetime performance index is also given.Then the UMVUE of the lifetime performance index is utilized to develop a new hypothesis testing.Finally,a practical example is illustrated that the test method is simple and easy to operate.Moreover,this method can be employed to determine whether the products achieve the required level.