Record Details

Quantification of epistemic and aleatory uncertainties in level-1 probabilistic safety assessment studies

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Quantification of epistemic and aleatory uncertainties in level-1 probabilistic safety assessment studies
 
Creator DURGA RAO, K
KUSHWAHA, HS
VERMA, AK
SRIVIDYA, A
 
Subject mathematical models
monte carlo methods
risk assessment
safety factor
 
Description There will be simplifying assumptions and idealizations in the availability models of complex processes and phenomena. These simplifications and idealizations generate uncertainties which can be classified as aleatory (arising due to randomness) and/or epistemic (due to lack of knowledge). The problem of acknowledging and treating uncertainty is vital for practical usability of reliability analysis results. The distinction of uncertainties is useful for taking the reliability/risk informed decisions with confidence and also for effective management of uncertainty. In level-1 probabilistic safety assessment (PSA) of nuclear power plants (NPP), the current practice is carrying out epistemic uncertainty analysis on the basis of a simple Monte-Carlo simulation by sampling the epistemic variables in the model. However, the aleatory uncertainty is neglected and point estimates of aleatory variables, viz., time to failure and time to repair are considered. Treatment of both types of uncertainties would require a two-phase Monte-Carlo simulation, outer loop samples epistemic variables and inner loop samples aleatory variables. A methodology based on two-phase Monte-Carlo simulation is presented for distinguishing both the kinds of uncertainty in the context of availability/reliability evaluation in level-1 PSA studies of NPP.
 
Publisher Elsevier
 
Date 2009-05-18T12:10:33Z
2011-12-08T07:22:06Z
2011-12-26T13:02:07Z
2011-12-27T05:48:06Z
2009-05-18T12:10:33Z
2011-12-08T07:22:06Z
2011-12-26T13:02:07Z
2011-12-27T05:48:06Z
2007
 
Type Article
 
Identifier Reliability Engineering and System Safety 92(7), 947-956
09518320
10.1016/j.ress.2006.07.002
http://hdl.handle.net/10054/1377
http://dspace.library.iitb.ac.in/xmlui/handle/10054/1377
 
Language en