The Analysis Method Of Causality Diagram Structure Important Degree

Research on Causality Diagram mainly to the fault diagnosis, especially for complex systems provides a method of fault diagnosis. In recent years, the application on the causality diagram has been extensively studied, both in industry and in many major security incidents aspects have been extensively studied in fault diagnosis of complex systems, how to quickly identify the cause of the malfunction, take immediate and the development of remedial measures to prevent recurrence failure is the main task of our study. Important structural analysis method is based on a qualitative analysis of cause and effect diagram minimal cut sets on the proposed remedy the difficulties encountered when computing complex causal model problem;while visually analyze the accident from the causal diagram construction the reason,the paper rise building fire Case-depth study of the structural importance of the analytical procedures. Research and development status from the background to understand cause and effect diagram, and analyzes causal map has been made of the research results, and then be inspired: on the one hand, studies the relationship between each event from the causal graph structure, analyze the impact on the outcome of an event cause event degree. High-rise building fire, for example, to establish a causal graph model by calculating the structure importance coefficient(we used)(iI?to represent, what short)(iI?), obtained from the analysis of cause of the accident causal structure of FIG findings. On the other hand, the rate of change from the perspective of the accident probability study cause of the accident, with the rate of change of the accident probability(ip)(I) to indicate the extent of its impact on the top event; first calculate the probability of top event expression based on the actual problem, followed by the top event the probability of seeking the first partial derivatives outcome probability rate of change, and by comparing the results of)(iI?andip)(I concluded that use)(iI?to study the structural problems of causality diagram practicable.Throughout the course of the study the probability of expression issues related to demand top event, calculated from the actual problems encountered told us that in order to obtain accurate results in the causal diagram is difficult to achieve, even whenthe practical problems encountered in It is known that the probability of a larger event causality and very complex situations, accurate calculation will spend a lot of time or even impossible to achieve less than desired results. To solve this problem, we use approximate calculation approximate solutions, after a detailed analysis of the calculation process, and can be seen from the calculation process this solution process is calculated in comparison with the exact solution is greatly simplified.