ExpertFTA: an expert's knowledge based software tool for fault tree analysis

Having an effective and systematic risk analysis and safety management strategy is imperative to avoid unwanted accidents in any process facility. Fault Tree Analysis (FTA) is a frequently used technique by design engineers for Probabilistic Risk Assessment (PRA). Imprecise, incomplete and vagueness of data can result uncertainty in output from FTA. The Dempster-Shafer Theory of Evidence (DST) addresses the incompleteness in data while fuzzy theory handles impreciseness or vagueness in data. -- A computer aided tool for FTA, ExpertFTA- is introduced in this thesis. Both DST and fuzzy theory arc considered to develop this software tool in order to aggregate knowledge from multiple experts. ExpertFTA can assists users (with little knowledge of FTA) to draw a fault tree and perform the analysis effectively. ExpertFTA helps users to create a fault tree, modify it and store (profiling) data for future reference. Users can perform qualitative, quantitative and sensitivity analysis of the fault tree from DST and fuzzy point of view. It also provides a report based on the generated fault tree. Several established design patterns arc implemented and object oriented concepts of Java, XML and XSLT are used in the development of ExpertFTA. -- None of the currently available commercial software for FTA has the capability of performing analysis based on DST and fuzzy logic. This tool is developed with the anticipation of using it for research purposes and also for industry personnel for detailed risk analysis. It is designed such a way that it can be extended with more functionality in the future