• 한국압력기기공학회 논문집
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• 제10권1호
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• pp.7-14
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• 2014

There has been extensive experience associated with the operation of SGs wherein it was believed, based on NDE, that throughwall tube indications were present within the tubesheet. The installation of the SG tubes usually involves the development of a short interference fit, referred to as the tack expansion, at the bottom of the tubesheet. The tack expansion was usually effected by a hard rolling process and thereafter, in most instance, by the expansion of a urethane plug inserted into the tube end and compressed in the axial direction. The rolling process by its very nature is considered to be intensive with regard to metalworking at the inside surface of the tube and would be expected to lead to higher residual surface stresses. Alternate repair criteria(ARC) in the tack expansion area have been developed and applied to nuclear power plants in USA, however domestic nuclear power plants have not applied ARC for tubes in tubeheet area yet. In consideration of the degradation characteristics of tubes in the Steam Generator tubesheet, this paper suggests ARC application for tubes in the steam generator tubesheet of the domestic nuclear power plants in order to assure life time of the steam generator as well as nuclear power plants.

• 에너지공학
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• 제26권2호
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• pp.50-63
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• 2017

복잡하고 다양한 계통으로 구성된 원자력발전소에서의 안전문화 저하 징후는 설비의 안전성능 저하를 유발할 수 있으며, 이에 대한 적절한 후속조치가 없을 경우 대형 사고를 발생시킬 수 있는 잠재적 원인이 된다. 따라서 원전의 안전성능에 대한 감시와 더불어 조직 및 관리측면에서의 안전문화를 모니터링 함으로써 안전문화 저하 징후를 파악할 필요가 있다. 따라서 본 논문에서는 원전 문제점 혹은 사건이 발생할 경우, 설비 측면보다는 조직의 안전문화관점에서 사건의 근본원인에 기여한 안전문화 취약요소를 평가하여 개선할 수 있는 사건기반 평가 방법론을 정립하였다. 이를 위해 국내 외 산업계에서 활용되고 있는 평가사례들을 검토하여 국내 원전 실정에 적합한 평가 방법론을 제안하였다.

• 수산해양교육연구
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• 제27권4호
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• pp.938-947
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• 2015

As many offshore plants are built domestically, many workers get various jobs in the offshore plants directly or indirectly. But workers(including seaman and non-seaman) still have hard time to getting the job in offshore plants because they still rely on personal contacts and limitation of adaptable positions. Now people who want to work at offshore plants have to get safety training under the regulation and request of IMO/STCW and OPITO. Recently OPITO reinforced offshore safety training and discussed the mutual agreement between IMO/STCW and OPITO. Therefore this study searched legal standards for offshore plant work and the trend of offshore safety training. Base on a survey among domestic delegates who completed BOSIET course from 2010, we now understand the actual situations in finding an effective way on how to advance domestic workers in the offshore plant industry.

• 한국압력기기공학회 논문집
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• 제9권1호
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• pp.35-39
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• 2013

The Operating Experience Report(OER) has written about the event and accident happened at a Nuclear Power Plant(NPP). The purpose of publishing the OER is to prevent the similar event or accident repeatedly by spreading the experience of a single plant to other plants personnel. Before initiating the analysis mentioned in this paper, 2,298 review reports for the same number of OER published from 2007 to June 2012 have been written to achieve the correct and objective statistics. The analysis introduced in this paper is performed with the various factors such as year, plant type, equipment, type of work, root-cause. The root-cause analysis is showed that the equipment problem is the major factor in domestic NPPs, but on the other hand human-error is the main part of the foreign NPPs. Moreover, while the number of the man-made event is decreasing, the equipment-made event is rapidly increasing in domestic NPPs.

• Journal of Radiation Protection and Research
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• 제23권4호
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• pp.251-257
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• 1998

국내 원전에 적용하기 위한 기체 방사성 물질 확산 및 피폭 평가 코드를 개발하였다. 정상 운전에 의한 기체 방사성 물질 확산 및 피폭 평가에는 직선 궤도 가우시안 플륨 모델을 사용하는 XOQDOQ 코드가 사용되어 왔다. 본 연구에서는 이 코드의 단점인 발전소 주변 지역에서의 바람 방향의 영향, 산악 지형에 대한 모델, 습식 침적에 대한 개선이 이루어졌다. 현실적인 유효 고도 보정 및 산악 침투 모델을 통해서 산악 지형에 대한 고려를 하였고, 바람 발생 확률 빈도를 수정하여 직선 궤도 모델을 보완하였다. 개발된 코드는 영광원전의 주민피폭선량평가를 위해 채택되었으며, 산악이 많은 우리 나라 다른 발전소에 적용하기 위해 산악지형 입력변경을 통하여 적절히 사용될 수 있을 것이다.

• 한국지진공학회논문집
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• 제24권3호
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• pp.123-128
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• 2020

Analysis of the 2016 Gyeongju earthquake and the 2017 Pohang earthquake showed the characteristics of a typical high-frequency earthquake with many high-frequency components, short time strong motion duration, and large peak ground acceleration relative to the magnitude of the earthquake. Domestic nuclear power plants were designed and evaluated based on NRC's Regulatory Guide 1.60 design response spectrum, which had a great deal of energy in the low-frequency range. Therefore, nuclear power plants should carry out seismic verification and seismic performance evaluation of systems, structures, and components by reflecting the domestic characteristics of earthquakes. In this study, high-frequency amplification factors that can be used for seismic verification and seismic performance evaluation of nuclear power plant systems, structures, and equipment were analyzed. In order to analyze the high-frequency amplification factor, five sets of seismic time history were generated, which were matched with the uniform hazard response spectrum to reflect the characteristics of domestic earthquake motion. The nuclear power plant was subjected to seismic analysis for the construction of the Korean standard nuclear power plant, OPR1000, which is a reactor building, an auxiliary building assembly, a component cooling water heat exchanger building, and an essential service water building. Based on the results of the seismic analysis, a high-frequency amplification factor was derived upon the calculation of the floor response spectrum of the important locations of nuclear power plants. The high-frequency amplification factor can be effectively used for the seismic verification and seismic performance evaluation of electric equipment which are sensitive to high-frequency earthquakes.

• 한국방사선학회논문지
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• 제9권5호
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• pp.269-277
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• 2015

세계적으로 수명을 다한 원자력발전소들이 증가하면서 노후화 된 원전의 해체에 대한 관심도 커져가고 있다. 특히 국토가 좁고 자원이 부족한 국내의 경우 원전을 해체하는데 있어 부지 재이용 문제는 하나의 중요한 사안이지만, 아직까지 부지 재이용을 위한 구체적인 법적 부지해제기준이 마련되어 있지 않다. 따라서 본 연구에서는 부지해제를 위한 IAEA의 국제적 안전기준(Safety Guide No. WS-G-5.1) 및 국내 관련기준, 미국 유럽 등 선진국들의 부지해제 사례들을 분석하였으며, 이를 바탕으로 적절한 선량기준 및 국내 부지해제 기준 수립 시 고려해야하는 사항들을 제언하였다. 이는 원전 해체 후 부지 재이용을 위한 국내 부지해제 기준 수립을 위한 기초자료로 활용될 것으로 판단된다.

• 한국안전학회지
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• 제39권1호
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• pp.82-95
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• 2024

Analyzing the aftermath of events at domestic nuclear power plants brings in the question: "Why do workers not comply with the prescribed procedures?" The current investigation of nuclear power plant events identifies their reasons considering the factors affecting the workers' behaviors. However, there are some complications to it: in addition to confirming the action such as an error or a violation, there is a limit to identifying the intention of the actor. To overcome this limitation, the study analyzed and examined the reasons for non-compliance identified in nuclear power plant events by Reason's rule-related behavior classification. For behavior analysis, I selected unit behaviors for events that are related to human and organizational factors and occurred at domestic nuclear power plants since 2017, and then I applied the rule-related behavior classification introduced by Reason (2008). This allowed me to identify the intentions by classifying unit behaviors according to quality and compliance with the rules. I also identified the factors that influenced unit behaviors. The analysis showed that most often, non-compliance only pursued personal goals and was based on inadequate risk appraisal. On the other hand, the analysis identified cases where it was caused by such factors as poorly written procedures or human system interfaces. Therefore, the probability of non-compliance can be reduced if these factors are properly addressed. Unlike event investigation techniques that struggle to identify the reasons for employee behavior, this study provides a new interpretation of non-compliance in nuclear power plant events by examining workers' intentions based on the concept of rule-related behavior classification.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.124.1-124
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• 2001

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.55.2-55
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• 2001