Conversion of Fault Tree into Credal Network for Probabilistic Safety Assessment of a Nuclear Power Plant

Lye, AT ORCID: 0000-0002-1803-8344, Estrada Lugo, Hector ORCID: 0000-0001-5929-6414 and Patelli, E ORCID: 0000-0002-5007-7247
(2019) Conversion of Fault Tree into Credal Network for Probabilistic Safety Assessment of a Nuclear Power Plant. In: 3rd International Conference on Nuclear Power Plants: Structures, Risk and Decommissioning, 2019-06-10 - 2019-06-11, London.

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The harnessing of nuclear energy as means to provide an alternative source of energy has helped provide numerous benefits in today's world such as cheap electricity and reduced carbon emissions. However, the use of such technology comes with its risks as history would point us to the Chernobyl nuclear reactor disaster, Three-mile Island Accident, and the most recent Fukushima-Daiichi catastrophe. With the current issue of global warming, the increased in demand for electricity world-wide, and the strong consideration by many countries in adopting nuclear power, this brings an even greater need to look into probabilistic safety assessment methods to quantify the risks associated with nuclear power plants. This conference paper seeks to apply the probabilistic concepts of statistical dependence of events and logical gate theory to transform a Fault-Tree model into a credal network to perform probabilistic safety assessment. The so called Fault-tree to Credal network conversion technique adopts probabilistic intervals to represent the imprecise state of the components of complex systems as well as allowing perform prediction and diagnostic analyses, differently from the Fault-Tree analysis. The imprecision is referred here as the epistemic uncertainty due to the lack of information or inconsistent data. In the scope of risk assessments, this model allows for the study of the dependability of the elements in the system and analyse the outcomes of different possible scenarios with its associated uncertainty. The Fault-tree to credal network conversion method is applied to produce a probability model for safety assessment of the reactor core system within the Three-Mile Island nuclear reactor as it is the critical system associated with loss of coolant accidents. This case study allows to show the capabilities of Fault-tree to credal network conversion.

Item Type: Conference or Workshop Item (Unspecified)
Depositing User: Symplectic Admin
Date Deposited: 20 Jun 2019 13:45
Last Modified: 09 Nov 2021 08:22