首项近似法的误差及使用条件的分析

Error of Leading Approximation Progress and Analysis of Its Use Conditions

针对在使用事故树法中采用首项近似法计算顶上事件的发生概率时可能出现的误差情况进行分析,结果表明:使用首项近似法计算顶上事件的发生概率可能出现误差很大,甚至会出现大于1的概率现象。由此认为用首项近似法计算顶上事件的发生概率除受到给定条件的限制外,还应受到其它条件如最小割集组数的限制。

Analysis was made in the light of the possible errors witch may be produced when the leading calculation progress in fault tree analysis is used to calculate the occurrence probability of top events. The analysis results ind icated that large errors may be produced or even the probability is larger tha n 1 when the leading calculation progress in fault tree analysis is used to cal culate the oc-currence probability of top events. From this it is considered tha t the use of leading calculation progress for the calculation of the occur-rence probability of top events is not only limited by the given con-ditions, but al so by other conditions such as the number of minimum cut-set groups.