为了确保高的可用性，在重大工程实践中往往采用具有容错结构的计算机双系统。双系统处理得到两个结果的异同性，历来是研究双系统容错的技术重点和难点。文章在双系统可用性分析、结果判错与选择、以及双工切换技术方面都有突破性的进展，并在重点工程中得以实现，取得显著效果。

To ensure the high availability, the duplex-computer system with fault tolerance architecture is used in crucial projects. The similarites and differences of the two results from the duplex system have been the key difficulty of this domain. In this paper, there are great progresses in the analysis of availability, the judgement over of two results and the switch over two systems. The techniques have been realized in an important project with significant effect.