混合威布尔分布参数估计的L-M算法

混合威布尔分布模型常用来分析具有多种失效模式的机械系统或零部件的可靠性寿命数据,为提高混合威布尔分布未知参数估计的精度,利用非线性最小二乘理论,建立了小子样条件下两重混合威布尔分布参数优化估计模型,将L-M算法用于优化求解。以概率图参数估计法的结果作为迭代初始值,提高了迭代求解的速度。计算实例表明利用该方法估计混合威布尔分布参数是可行的,而且能够获得较精确的结果。

Parameters Estimation for Mixed Weibull Distribution Using L-M Algorithm

Mixed Weibull distribution is usually used to model reliability of products with more than one failure modes. Due to the difficulty of estimation of distribution parameters, it has not been widely used. In this paper, a mixed model involving two Weibull distributions is considered; and its parameters estimation model is established using nonlinear least square theory. Levenberg-Marquardt algorithm is used to solve the optimization problem. To reduce iterative time, the estimator from graphical method is used as initial value. A numerical example is employed to illustrate the feasibility and accuracy of the proposed method.