• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.195-195
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• 2002

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.198.2-198
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• 2002

• Proceedings of the Korean Nuclear Society Conference
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• 2003.10a
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• pp.513-513
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• 2003

• Proceedings of the Korean Nuclear Society Conference
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• 2003.10a
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• pp.137.1-137.1
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• 2003

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.257-258
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• 2018

• Nuclear Engineering and Technology
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• v.46 no.4
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• pp.541-546
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• 2014

Probabilistic Safety Assessment (PSA) has been widely used to estimate the overall safety of nuclear power plants (NPP) and it provides base information for risk informed application (RIA) and risk informed regulation (RIR). For the effective and correct use of PSA in RIA/RIR related decision making, the risk estimated by a PSA model should be as realistic as possible. In this work, a best-estimate thermal-hydraulic analysis of loss-of-coolant accidents (LOCAs) for the Hanul Nuclear Units 3&4 is first carried out in a systematic way. That is, the behaviors of peak cladding temperature (PCT) were analyzed with various combinations of break sizes, the operating conditions of safety systems, and the operator's action time for aggressive secondary cooling. Thereafter, the results of the thermal-hydraulic analysis have been reflected in the improvement of the PSA model by changing both accident sequences and success criteria of the event trees for the LOCA scenarios.

• Archives of Craniofacial Surgery
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• v.19 no.1
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• pp.41-47
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• 2018

Background: The number of surgical risks recalled by a patient after surgery can be used as a parameter for assessing how well the patient has understood the informed consent process. No study has investigated the usefulness of a self-developed mobile application in the traditional informed consent process in patients with a nasal bone fracture. This study aimed to investigate whether delivery of information, such as surgical risks, through a mobile application is more effective than delivery of information through only verbal means and a paper. Methods: This prospective, randomized study included 60 patients with a nasal bone fracture. The experimental group (n=30) received preoperative explanation with the traditional informed consent process in addition to a mobile application, while the control group (n=30) received preoperative explanation with only the traditional informed consent process. Four weeks after surgery, the number of recalled surgical risks was compared for analysis. The following six surgical risks were explained: pain, bleeding, nasal deformity, numbness, nasal obstruction, and nasal cartilage necrosis. Results: The mean number of recalled surgical risks among all patients was $1.58{\pm}0.56$. The most frequently recalled surgical risk was nasal deformity in both groups. The mean number of recalled surgical risks was $1.72{\pm}0.52$ in the experimental group and $1.49{\pm}0.57$ in the control group. There was a significant association between mobile application use and the mean number of recalled surgical risks (p=0.047). Age, sex, and the level of education were not significantly associated with the mean number of recalled surgical risks. Conclusion: This study found that a mobile application could contribute to the efficient delivery of information during the informed consent process. With further improvement, it could be used in other plastic surgeries and other surgeries, and such an application can potentially be used for explaining risks as well as delivering other types of information.

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.157-163
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• 2018

This paper describes design improvement to a research rector for safety enhancement using Probabilistic Safety Assessment (PSA). This PSA under reactor design was undertaken to assess the level of safety for the design of a research reactor and to evaluate whether it is probabilistically safe to operate and reliable to use. The scope of the PSA reported here is a Level 1 PSA, which addresses the risks associated with the core damage. The technical objectives of this study were to identify accident sequences leading to core damage and to derive design improvement from the dominant accident sequences through the sensitivity analysis. The AIMS-PSA and FTREX were used for the this PSA of the research reactor. The criterion for inclusion was all sequences with a point estimate frequency greater than a truncation value of 1.0E-14/yr. The final result indicates a point estimate of 6.79E-05/yr for the overall Core Damage Frequency (CDF) attributable to internal initiating events for the research reactor under design. Based on the dominant accident sequences from the PSA, the seven kinds of sensitivity analysis were performed and some design improvement items were derived. When the five methods to improve the safety were all applied to the reactor design and emergency operating procedure, its risk was reduced to about 1.21E-06/yr from 6.79E-05/yr. The contribution of LOCA and LOEP with high CDF were significantly reduced by the sensitivity analysis. The safety of the research reactor was well improved and the risk was reduced than before adapting the design improvement gotten from the sensitivity analysis. The present study indicated that the research reactor has the well-balanced safety in regard to each initiating event contribution to CDF. The PSA methodology is very effective to improve reactor safety in a conceptual design phase and especially, Risk-informed design(RID) is very nice way to find the deficiencies of research reactor under design and to improve the reactor safety by solving them.

• Journal of Applied Reliability
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• v.10 no.1
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• pp.73-91
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• 2010

All activities relate to railway traffic involve risk and that these arise from a combination of the nature of operating activities. Proper management system is required to provide the organizational capability to reveal, analyse and address these weaknesses over time and in reasonably practicable ways, which will determine the rate at which risks can be further reduced. This paper presents a systematic risk analysis approach to safety planning and decision making, informed by a range of risk assessment techniques. An railway organization's safety management system is also presented that shows the approaches taken to minimize the external risks, and identify the shared risks and explain how they will be controlled through collaboration with others.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.793-794
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• 2005