TREEZZY2, a Fuzzy Logic Computer Code for Fault Tree and Event Tree Analyses

  • Salvatore Bellini
  • Maddalena Casamirra
  • Francesco Castiglia
Conference paper


In conventional approach to reliability analysis using logical trees methodologies, uncertainties in system components or basic events failure probabilities are approached by assuming probability distribution functions. However, data are often insufficient for statistical estimation, and therefore it is required to resort to approximate estimations. Moreover, complicate calculations are needed to propagate uncertainties up to the final results. In our work, in order to take account of the uncertainties in system failure probabilities, the methodology based on fuzzy sets theory is used both in fault tree and event tree analyses. This paper just presents our work in this issue, which resulted in a computer program named TREEZZY (TREE fuZZY).


Failure Probability Fault Tree Failure Data Fault Tree Analysis Event Tree Analysis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag London 2004

Authors and Affiliations

  • Salvatore Bellini
    • 1
  • Maddalena Casamirra
    • 1
  • Francesco Castiglia
    • 1
  1. 1.Mariarosa Giardina Department of Nuclear EngineeringUniversity of PalermoItaly

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