The varied knowledge expressions,such as the compound belief networks,the automatic identifying faults knowledge and multiple in ference patt ern,are also put forwared.

• 提出复合嵌套概率推理网络多种知识表达方式、故障知识的自动识别处理及多推理方式并存的推理机制等系统特点。通过诊断实例，验证了系统诊断的可行性。