含模糊随机变量的多模式系统广义失效概率计算的内插迭代线抽样方法  

General Failure Probability Assessment for Multi-Mode System with Fuzzy-Random Variables by Improved Line Sampling

作　　者：王宏伟[1,2] 吕震宙[1] 赵洁[1] 

机构地区：[1]西北工业大学,西安710072 [2]中国人民解放军96411部队,宝鸡721013

出　　处：《应用力学学报》2009年第2期365-369,414,共5页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(10572117,50875213);新世纪优秀人才支持计划(NCET-05-0868);航空科学基金(2007ZA53012);民口863计划(2007AA04Z401)

摘　　要：通过正则化基本变量的度量空间,定义了单个基本变量同时具有模糊和随机双重不确定性时的广义失效概率。在广义失效概率的计算中,模糊随机变量被等价变换为随机变量,从而使得广义失效概率的计算变换为随机失效概率的计算。当模糊随机变量的密度函数和隶属函数均为正态型时,推导了其等价概率密度函数的形式和参数。采用自适应线抽样方法对基本变量同时具有模糊和随机不确定性时的多模式广义失效概率进行了计算,并采用数值算例对自适应线抽样广义失效概率计算方法的效率和精度进行了验证。算例分析表明该方法的计算结果是合理的,并且由于自适应线抽样法具有较高的效率和精度,因而所提方法具有一定的工程意义。Normalizing the measurement of basic variable space,the general failure probability where the basic variable possesses both fuzzy uncertainty and random uncertainty,called fuzzy-random variable,simultaneously is defined.In the calculation of the defined general failure probability,the fuzzy-random variable is transformed into a random variable equivalently,and then the general failure probability is transformed into an equivalent random failure probability.As both probability density function(PDF) describing the randomness and membership function describing the fuzziness of the fuzzy-random variable are normal,the formulation and parameters of the equivalent PDF are derived in this contribution.Adaptive line sampling method is employed to assess the general failure probability of the structural system with multiple failure modes.The numerical examples demonstrate the precision and the efficiency of the adaptive line sampling based on the general failure probability assessment.

关 键 词：自适应线抽样 模糊性 随机性 广义失效概率 

分 类 号：TB114.3[理学—概率论与数理统计]