The Experts below are selected from a list of 171 Experts worldwide ranked by ideXlab platform
Jinho Oh - One of the best experts on this subject based on the ideXlab platform.
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development of network based probabilistic safety assessment a tool for Risk Analyst for nuclear facilities
Progress in Nuclear Energy, 2019Co-Authors: Shinyoung Kwag, Jinho OhAbstract:Abstract The probabilistic safety assessment (PSA) methodology has been developed and utilized to assess the overall Risks to a nuclear facility. However, PSAs are challenged when it comes to accurately describing relations among events, or to accommodate newly observed data, or to consider severe accident scenarios within a current framework. To overcome such challenges and take advantage of the merits of recent systems analysis concepts, this paper develops an improved PSA approach, by integrating the current fault tree-based PSA framework with a Bayesian network. The proposed approach enables one to account for event relations beyond logic gates, to incorporate additional field observations and to conduct vulnerability assessments in an accident condition. To demonstrate the proposed Bayesian-based method, it is applied to a nuclear research reactor recently constructed in JUST, Irbid, Jordan. Several case studies are conducted to demonstrate how realistic information about events and from field inspections changes the core damage Risk. In addition, critical scenarios are investigated for an accident, to perform vulnerability assessment beyond a design-basis event. Consequently, it is shown that the proposed approach provides an enhanced framework for Risk assessments at nuclear facilities. This framework is ultimately expected to improve decision support for Risk-informed designs.
Shinyoung Kwag - One of the best experts on this subject based on the ideXlab platform.
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development of network based probabilistic safety assessment a tool for Risk Analyst for nuclear facilities
Progress in Nuclear Energy, 2019Co-Authors: Shinyoung Kwag, Jinho OhAbstract:Abstract The probabilistic safety assessment (PSA) methodology has been developed and utilized to assess the overall Risks to a nuclear facility. However, PSAs are challenged when it comes to accurately describing relations among events, or to accommodate newly observed data, or to consider severe accident scenarios within a current framework. To overcome such challenges and take advantage of the merits of recent systems analysis concepts, this paper develops an improved PSA approach, by integrating the current fault tree-based PSA framework with a Bayesian network. The proposed approach enables one to account for event relations beyond logic gates, to incorporate additional field observations and to conduct vulnerability assessments in an accident condition. To demonstrate the proposed Bayesian-based method, it is applied to a nuclear research reactor recently constructed in JUST, Irbid, Jordan. Several case studies are conducted to demonstrate how realistic information about events and from field inspections changes the core damage Risk. In addition, critical scenarios are investigated for an accident, to perform vulnerability assessment beyond a design-basis event. Consequently, it is shown that the proposed approach provides an enhanced framework for Risk assessments at nuclear facilities. This framework is ultimately expected to improve decision support for Risk-informed designs.
Antoine Rauzy - One of the best experts on this subject based on the ideXlab platform.
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notes on computational uncertainties in probabilistic Risk safety assessment
Entropy, 2018Co-Authors: Antoine RauzyAbstract:In this article, we study computational uncertainties in probabilistic Risk/safety assessment resulting from the computational complexity of calculations of Risk indicators. We argue that the Risk Analyst faces the fundamental epistemic and aleatory uncertainties of Risk assessment with a bounded calculation capacity, and that this bounded capacity over-determines both the design of models and the decisions that can be made from models. We sketch a taxonomy of modelling technologies and recall the main computational complexity results. Then, based on a review of state of the art assessment algorithms for fault trees and event trees, we make some methodological proposals aiming at drawing conceptual and practical consequences of bounded calculability.
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Notes on Computational Uncertainties in Probabilistic Risk/Safety Assessment
Entropy (Basel Switzerland), 2018Co-Authors: Antoine RauzyAbstract:In this article, we study computational uncertainties in probabilistic Risk/safety assessment resulting from the computational complexity of calculations of Risk indicators. We argue that the Risk Analyst faces the fundamental epistemic and aleatory uncertainties of Risk assessment with a bounded calculation capacity, and that this bounded capacity over-determines both the design of models and the decisions that can be made from models. We sketch a taxonomy of modelling technologies and recall the main computational complexity results. Then, based on a review of state of the art assessment algorithms for fault trees and event trees, we make some methodological proposals aiming at drawing conceptual and practical consequences of bounded calculability.
G. C. Avontuur - One of the best experts on this subject based on the ideXlab platform.
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an implementation of reliability analysis in the conceptual design phase of drive trains
Reliability Engineering & System Safety, 2001Co-Authors: G. C. Avontuur, K Van Der WerffAbstract:Abstract Reliability analysis will have a major influence on the design, if it is applied during the conceptual design phase. This will result in more reliable and less expensive structures; a structure that is reliable in concept is less expensive than a structure that is not reliable in concept, but is improved in a later phase of the design process. The introduction of reliability analysis in the conceptual design phase will have important consequences for the design process. The designer and Risk Analyst would have to work closely together and the Risk Analyst has to make fault tree analyses for many design solutions, increasing the cost of the design. Automation can make the analysis less complex, can reduce the time of an analysis, and can prevent errors. An implementation in software can take over complex parts of the analysis from the designer and Risk Analyst, and it can execute these tasks much faster and more accurate. If the designer can execute the analysis himself, he does not depend on the availability of a Risk analysis expert. Then, he can immediately decide if and how the design needs improvement. Also, the designer can optimise a structure by analysing a number of concepts. Thus, reliability analysis can be applied in many more cases than before, which will lead to better designs. This article discusses the role of reliability analysis in the design process of drive systems at the Mechanical Engineering Department of the Construction Division of the Ministry of Transport, Public Works and Water Management. It gives an abstract description of the functions of a drive system to find an automated reliability analysis method.
Ian Savage - One of the best experts on this subject based on the ideXlab platform.
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RAILROAD SAFETY AND PUBLIC POLICY
2015Co-Authors: Ian SavageAbstract:This paper discusses the safety challenges faced by railroads in the United States. It discusses and evaluates public policy dealing with trespassing, grade crossing collisions, occupational injuries and operational accidents. The primary conclusion is that the government oversight body, the Federal Railroad Administration (FRA), should take on the role of teacher and Risk Analyst rather than that of police officer. By doing so the FRA can more effectively target safety problems, and do so at reduced cost
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Railroad safety and public policy
Journal of the Transportation Research Forum, 1999Co-Authors: Ian SavageAbstract:This paper discusses the safety challenges faced by railroads in the U.S. It discusses and evaluates public policy dealing with trespassing, grade crossing collisions, occupational injuries and operational accidents. The primary conclusion is that the government oversight body, the Federal Railroad Administration (FRA), should take on the role of teacher and Risk Analyst, rather than that of police officer. By doing so, the FRA can more effectively target safety problems and do so at reduced cost.
