• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.545-548
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• 2008

In this study, the concept of safety impact assessment to achieve 'Design-for-Safety' in design phase is introduced. For this purpose, safety impact assessment model was devised and a methodology using the risk-based safety impact assessment approach for NATM of tunnel projects is suggested. The suggested methodology includes safety information survey, classification of safety impact factors caused by design and construction, and quantitative estimation of magnitude and frequency of safety impact factors. A real-world case study on the safety impact assessment of a tunnel construction project is also provided in the paper.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1372-1386
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• 2018

Despite recent advances in multi-hazard analysis, the complexity and inherent nature of such problems make quantification of the landslide effect in a probabilistic safety assessment (PSA) of NPPs challenging. Therefore, in this paper, a practical approach was presented for performing an earthquake-induced landslide PSA for NPPs subject to seismic hazard. To demonstrate the effectiveness of the proposed approach, it was applied to Korean typical NPP in Korea as a numerical example. The assessment result revealed the quantitative probabilistic effects of peripheral slope failure and subsequent run-out effect on the risk of core damage frequency (CDF) of a NPP during the earthquake event. Parametric studies were conducted to demonstrate how parameters for slope, and physical relation between the slope and NPP, changed the CDF risk of the NPP. Finally, based on these results, the effective strategies were suggested to mitigate the CDF risk to the NPP resulting from the vulnerabilities inherent in adjacent slopes. The proposed approach can be expected to provide an effective framework for performing the earthquake-induced landslide PSA and decision support to increase NPP safety.

• Journal of the Korea Safety Management & Science
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• v.20 no.1
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• pp.1-9
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• 2018

As the chemical industry becomes more advanced, the awareness of chemical accidents is rising, and legal systems for chemical safety management are strengthened. In this study, quantitative risk assessment of liquid chlorine leak was conducted. Risk assessment was performed in the order of frequency analysis, consequence analysis, and risk calculation. The individual risk was presented in the form of contour lines. The social risk was expressed by the FN curve. The risk of day and night was in an unacceptable area, so it was required to mitigate risk. Therefore in-building, which could trap the pool, was selected as a risk mitigation measure. As a result of the cost benefit analysis, it was concluded that this measure should be reasonably implemented.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.3
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• pp.61-74
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• 2001

The prevention of marine accidents has been a major topic in marine society and various policies and countermeasures has been developed, applied to the industries. Formal Safety Assessment is a structured and systematic methodology, aimed at enhancing maritime safety, including protection of life, health, the marine environment and property, by using risk and cost-benefit assessments. In addition, it provides a means of being proactive, enabling potential hazards to be considered before a serious accident occurs. In this paper, we has been screening and ranking of hazards using fuzzy structural modeling method and quantitative risk assessment for the ship's collision in the last 10 years marine accidents.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.1
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• pp.1-9
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• 2017

LNG has significant advantages in regard to environmental aspects comparing with conventional fuel oil. In fact, it is estimated that NOx and SOx emission can be reduced by about 90% and 100%, respectively in case of using LNG as a fuel. LNG-fuelled ship has been considered to be the best option both from an environmental and an economic point of view. Along with these trends, some major shipyards and Classification Societies have started to carry out the risk-based system design for LNG-fuelled ship such as passenger ship, platform supply vessel and large container vessel etc. However, new conceptual gas fuelled ship has high risk level compared with vessel using traditional crude oil especially in view of gas explosion accident. Therefore safety area where installed fuel gas supply system is required risk based system design with special considerations. On this paper, the entire process necessary for the quantitative risk analysis was explained to meet the satisfactory safety level of gas fuelled ship.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.59-73
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• 2016

The demand for subsurface transport is increasing. The users and the operators of road tunnels are exposed to risks with different causes. One main cause, however, is the traffic situation in the event of accidents. The importance of a Quantified Risk Assessment is increasing to quantify the safety of road tunnels and to balance the requirements (capacity, reliability, availability, maintainability and safety) of various stakeholders. Although there are classical methods for risk assessments, such as ETA and FTA. These methods are used for relatively simple cases because it could not relevantly reflect the diversity and relationship of the parameters. Therefore, a quantitative risk assessment based on Bayesian Probabilistic Networks considering interdependence between the parameters of a complex underground system as a double deck tunnel is provided.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.34-34
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• 2018

• Journal of the Korean Society of Safety
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• v.14 no.2
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• pp.97-102
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• 1999

This study is to develope the quantitative risk assessment program for consequence analysis of fire and explosion (PML-Chem), which is applicable to the chemical plants. The advantages of PML-Chem is easy to use and acquire results. Especially, PML-Chem was embedded real weather condition database for major chemical plants in ${\bigcirc}{\bigcirc}$ complex in country. Also, reliability of PML-Chem was verified through comparing PML-Chem with PHAST-Professional which is already commercial.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.197-197
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• 2002

In terms of the risk assessment, qualitative and quantitative informations are needed to estimate the exposures of environmental pollutants, which may create risks, and those are the information according to the changes caused by the movement of substances from the pollutant and duration.(omitted)

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.37-41
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• 2018

Process safety technology has developed from qualitative methods such as HAZOP (hazard and operability study) to semi-quantitative methods such as LOPA (layer of protection analysis), and quantitative methods are actively studied these days. Quantitative risk assessment (QRA) is often based on fault tree analysis (FTA). FTA is efficient, but difficult to apply when failure events are not independent of each other. This problem can be avoided using a Markov process (MP). MP requires definition of all possible states, and thus, generally, is more complicated than FTA. A method is proposed in this work that uses an MP model and a Weibull distribution model in order to construct a reliability model for multiple dependent failures. As a case study, a pressure safety valve (PSV) is considered, for which there are three kinds of failure, i.e. open failure, close failure, and gas tight failure. According to recently reported inspection results, open failure and close failure are dependent on each other. A reliability model for a PSV group is proposed in this work that is to reproduce these results. It is expected that the application of the proposed method can be expanded to QRA of various systems that have partially dependent multiple failure states.