CAJ | 학술논문

当模糊变量的隶属函数为正态型时,可以将模糊随机可靠性及可靠性灵敏度转化为随机可靠性及可靠性灵敏度,并利用复合函数求导法则求解模糊随机失效概率对正态型隶属函数分布参数的灵敏度.对于对称抛物型隶属函数,文中提出了"改进最大最小"法和"改进等面积"法两种近似等价正态化方法,从而将模糊随机可靠性问题转换为随机可靠性问题,并利用线抽样方法分析之.算例结果表明,由于"改进最大最小"法所得的等价正态型隶属函数能在函数图形尾部更好地近似对称抛物型隶属函数,因而"改进最大最小"法更适用于模糊变量的隶属函数为对称抛物型分布时模糊随机可靠性及可靠性灵敏度的近似计算.
당모호변량적대속함수위정태형시,가이장모호수궤가고성급가고성령민도전화위수궤가고성급가고성령민도,병이용복합함수구도법칙구해모호수궤실효개솔대정태형대속함수분포삼수적령민도.대우대칭포물형대속함수,문중제출료"개진최대최소"법화"개진등면적"법량충근사등개정태화방법,종이장모호수궤가고성문제전환위수궤가고성문제,병이용선추양방법분석지.산례결과표명,유우"개진최대최소"법소득적등개정태형대속함수능재함수도형미부경호지근사대칭포물형대속함수,인이"개진최대최소"법경괄용우모호변량적대속함수위대칭포물형분포시모호수궤가고성급가고성령민도적근사계산.
In the case of the fuzzy variables possess Gaussian membership functions, the fuzzy random failure probability and reliability sensitivity can be transformed into the random ones. After that the chain rule was employed to obtain the sensitivity of the fuzzy random failure probability with respect to the distribution parameters of Gaussian membership function. For the symmetric parabolic membership function, the improved max-min method and the improved equivalent-area method were presented to transform the symmetric parabolic membership function to Gaussian one equivalently. The fuzzy random reliability problem can be transformed into the random one, which can be analyzed by the line sampling method. Since the symmetric parabolic membership function can be well approximated by equivalent Gaussian one based on the improved max-min method at the tail of the membership function graph, which is illustrated by the examples. Hence the improved max-min method is more suitable for the estimation of the fuzzy random failure probability and reliability sensitivity, where the fuzzy variables possess the symmetric parabolic membership functions.