双应力恒加试验Weibull分布型产品置信可靠性评估模型

为了有效快速评估高可靠性长寿命产品在正常应力条件下的可靠性，提出了一种双应力恒加试验Weibull分布型产品置信可靠性评估模型。首先，采用加速寿命试验(accelerated life test，ALT)技术，建立广义Eyring-Weibull可靠性模型，假定试验各应力水平组合下Weibull分布的形状参数相同，且尺度参数与各应力水平组合间呈对数线性关系。其次，给出了Weibull分布定时截尾双应力恒加试验的极大似然估计(maximum likelihood estimation，MLE)方法、与似然函数相关的Fisher信息矩阵以及模型参数的渐近协方差矩阵，构造了模型参数和一些可靠性指标的渐近置信区间。最后，通过仿真算例证明了所提方法的可行性。

Confidence reliability evaluation model of dual constant-stress accelerated life test for Weibull distribution product

In order to evaluate the reliability of high reliability and long life products under normal stress conditions effectively and quickly, a confidence reliability evaluation model of dual constant-stress accelerated life test (DCSALT) for Weibull distribution product is proposed. Firstly, the generalized Eyring-Weibull reliability model is established by using the accelerated life test (ALT) technology. In this model, it is assumed that the Weibull distribution has constant shape parameter and a log-linear relation between its scale parameter and each stress level combination. Secondly, a maximum likelihood estimation (MLE) method for DCSALT with fixed time censoring of the Weibull distribution, the Fisher information matrix realted to the likelihood function, and the asymptotic covariance matrix of the model parameters is presented. Furthermore, the asymptotic confidence intervals of the model parameters and some reliability indexs are constructed. Finally, the simulation example demonstrates the feasibility of the proposed method.