中文摘要：

针对冗余复杂系统的多故障诊断问题，为减小计算量和期望测试费用，设定一个概率值作为概率阈，忽略发生概率低于这个值的多故障状态，提出了一种基于概率阈的冗余多故障诊断策略。该策略首先对相关矩阵模型进行转化，并舍弃概率低于概率阈故障状态，然后用Roll—out算法对基于信息熵的诊断策略进行优化，并给出了计算步骤与方法。实例表明，与文献中方法相比该策略虽然降低了一定的准确度，但减少了更大比例的期望测试费，而且降低了相关性矩阵模型的规模，缩短了计算时间。

英文摘要：

Aimed at the problem of the multiple fault diagnosis of redundant system, a multiple fault diag- nosis strategy for redundant system based on probability is proposed to reduce the computation and the ex- pectant costs under condition that a probability value is set as a probability threshold and the multi-fault state whose probability is lower than the value of this probability threshold is neglected. First, this strate- gy is used to optimize the relation matrix model, and give up the multi-fault states whose probability is lower than the probability threshold. And then, Rollout algorithm is used to optimize the information en- tropy based diagnosis strategy. The example demonstrates that though the expectant costs are lowered by the strategy into a certain accuracy, a great proportion of the expectant test costs is reduced , the size of the fault-test relation matrix model is minimized, and the calculation time is reduced.