中文摘要：

在已知系统组成单元的区间可靠度或单元区间失效概率前提下,根据扩张原理,利用区间分析方法,分析了串联系统、并联系统、先串后并系统、先并后串系统、r/n（G）系统等典型系统的区间可靠性。基于区间数比较的可能度公式,提出了准一致性概念。分析了典型系统的区间可靠度特性与其点可靠度特性之间的准一致性。这一结果进一步完善了系统区间可靠性分析理论。

英文摘要：

The interval reliability of some typical systems, such as series system, parallel system, seriesparallel system, parallel-series system, and r/n （G） system, etc. is studied based on the extension principle and the interval analysis. The interval reliability or interval failure probability of elements is analyzed. On the basis of the possibility degree for ranking interval numbers, a new concept the quasi-consistency is proposed. The conclude is that there is a quasi-consistency relationship between the characteristics of the interval reliability and point reliability for a typical system. The result improves the theory of system interval reliability.