船舶驾驶失效搁浅概率的混合事件树分析

Hybrid Event Tree Calculation of Ship Grounding Probability Caused by Piloting Failure

针对传统事件树不能分析和考虑人因错误为主的基本事件的发生概率及其敏感性和不确定性这一问题 ,通过引入模糊错误率及模糊错误概率的概念 ,将传统事件树中人因错误为主的基本事件的发生概率用模糊错误率表示 ,非人因错误为主的基本事件的发生概率用模糊概率表示 .采用混合事件树方法得到了船舶驾驶失效引起的搁浅的模糊概率 ,定义了模糊敏感性和不确定性因子并对其进行了分析 ,制定了减小船舶搁浅事故发生概率的相关措施 .计算结果表明 ,本文提出的方法在处理包含人因错误为主的事件的船舶搁浅概率计算问题时是有效的 .

The probability of occurrence of human-error-dominated event can not be effectively handled by using conventional event tree method, in which it is also impossible to consider the sensitivity and uncertainty of basic events' probabilities. To overcome these disadvantages, the concepts of fuzzy error rate and fuzzy error possibility were introduced to represent the failure probability of human-error-dominated event, while the fuzzy probability was used to represent the failure probability of non-human-error-dominated event. Based on it, the fuzzy probability of ship grounding with piloting failure was calculated by a hybrid event tree method. Moreover, the fuzzy sensitivity index and the fuzzy uncertainty index were defined. Some grounding probability reducing measures were verified by the sensitivity and uncertainty analysis. The results indicate that the proposed approach is useful in analyzing the probability of occurrence of human-error-dominated event.