Aiming at the problems that traditional fuzzy Petri nets can't give consideration to the fuzziness and randomness of un-certain knowledge,the expression of causality in complex fault,quantitative reasoning is lack of hierarchy and can not be solved locally,a hierarchical fuzzy Petri net based on cloud model is constructed to strengthen fuzzy Petri net The ability of knowledge representation and the efficiency of reasoning process are improved.The causal relationship between system failure modes and fail-ure causes is modeled by expert knowledge and Petri net hierarchical decomposition principles,which makes the fault modeling more structured and more flexible;the cloud model is applied to deal with the fuzziness and uncertainty of knowledges;the corre-sponding reasoning is given by reasonably considering local weight and global weight,combining with Petri net hierarchical de-composition principles and cloud aggregation operators.Example verification shows that the proposed method can effectively as-sess the risk of the system,and is superior to other methods in knowledge representation and reasoning.
Risk AssessmentFuzzy Petri Net(FPN)Cloud ModelHierarchical Decomposition Principles
万方数据
维普
