双参数指数分布下定数截尾恒加试验的统计分析

Statistical Analysis of Type Ⅱ Censoring Data from Constant-Stress Accelerated Life Testing Method under Two-Parameter Exponential Distribution Law

设产品寿命服从双参数指数分布，尺度参数（失效率）为λ＞０，位置参数（保证寿命）为μ＞０，在加速应力水平Ｓｉ下，失效率和保证寿命的加速模型分别为本文给出了定数截尾情况下对由恒定应力加速寿命试验得到的数据进行统计分析的方法。获得了参数β０，β１，β２的ＢＬＵＥ（最佳线性无偏估计）以及α０，α１的近似ＢＬＵＥ。然后由模型可以求得在正常应力水平Ｓ０下各种可靠性特征量的估计。随机模拟的结果表明，本文给出的统计方法具有较高的精度。

Suppose that the distribution of the life time of the products follows the twoparameter exponential law,the scale parameter (failure rate) is λ>0, and the location parameter(guarantee) is μ>0. Under the stress Si, the failure rate accelerated model and the guarantee accelerated model areandrespectively. In this paper, the statistical analysis of type Ⅱ censoring data is given with theconstant--stress accelerated life testing method. The Best Linear Unbiased Estimator (BLUE)of the coefficients β0, β1, and β2 of the failure rate accelerated model,and the approximate BLUEof the coefficients α0 and α1 of the guarantee accelerated model are obtained. Using these twomodels,the estimators of the various reliability characteristics under the usual stress S0 are obtained too. The results of random simulation show that the methods given above have highprecision.