• 대한기계학회논문집A
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• 제32권8호
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• pp.668-677
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• 2008

In nuclear power plants, ferritic low alloy steel nozzle was connected with austenitic stainless steel piping system through alloy 82/182 butt weld. Accurate estimation of residual stress for weldment is important in the sense that alloy 82/182 is susceptible to stress corrosion cracking. There are many results which predict residual stress distribution for alloy 82/182 weld between nozzle and pipe. However, nozzle and piping system usually connected through safe end which has short length. In this paper, residual stress distribution for pressurizer nozzle of Kori nuclear power plant was predicted using FE analysis, which consideded safe end. As a result, existing residual stress profile was redistributed and residual stress of inner surface was decreased specially. It means that safe end should be considered to reduce conservatism when estimating the piping system.

• Journal of Nuclear Fuel Cycle and Waste Technology
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• 제1권1호
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• pp.37-47
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• 2013

This paper describes basic plans for the development of a radioactive waste disposal facility with the introduction of Nuclear Power Plants (NPPs) for Kenya. The specific objective of this study was to estimate the total projected waste volumes of low- and intermediate-level radioactive waste (LILW) expected to be generated from the Kenyan nuclear power programme. The facility is expected to accommodate LILW to be generated from operation and decommissioning of nuclear power plants for a period of 50 years. An on-site storage capacity of 700 $m^3$ at nuclear power plant sites and a final disposal repository facility of more than 7,000 $m^3$ capacity were derived by considering Korean nuclear power programme radioactive waste generation data, including Kori, Hanbit, and APR 1400 nuclear reactor data. The repository program is best suited to be introduced roughly 10 years after reactor operation. This study is important as an initial implementation of a national LILW disposal program for Kenya and other newcomer countries interested in nuclear power technology.

• 대한기계학회논문집A
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• 제21권7호
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• pp.1089-1096
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• 1997

In this paper, Rancho Seco transient which is reported as a typical pressurized thermal shock event is postulated to be occuring in the Kori unit 1 plant, the oldest nuclear power plant in Korea. For the given material properties, transient history such as temperature and pressure, and postulated flaw, the stress distribution is obtained to calculate stress intensities for a wide range of assumed crack sizes. The stress intensities are compared with the fracture toughness, which is determined using the material properties and the distribution of the nil ductility transition temperature, to determine if cracking is expected to occur during the transient. The allowable operating year for the transient is determined and the evaluation results are discussed.

• Nuclear Engineering and Technology
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• 제26권1호
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• pp.41-53
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• 1994

1991년 2월 미하마원전에서 발생한 증기발생기 세관 파열사고에 대한 경험을 바탕으로, 본 사고에 대한 고리 1호기의 대처능력을 평가하기 위하여 해석을 수행하였다. 고리 1호기의 계통설계 및 운전조건은 미하마 2호기와 아주 유사하기 때문에 고리 1호기에서 발생한 가상의 증기발생기 세관 파열사고시의 사고경위 및 전개에 대한 평가가 필요하였다. 해석은 고리 1호기 EOP를 근거로 현실적으로 가능하게 수행되었다. 해석결과, 파열된 세관을 통한 누출은 사고후 약 40분 후에 정지되었으며, 고리 1호기는 유사한 증기발생기 세관 파열사고의 경우 충분한 대처능력이 있음을 보였다. 그러나, SI 신호작동후 소외전원으로 부터의 비안전등급 AC전원으로 단절되는 설계에 대한 재고가 필요하며, EOP의 운전절차가 운전원의 적절한 판단을 요구하기에는 다소 충분치 못함을 보였다. 또한 미하마 원전의 사고를 실험적으로 모사한 LSTF의 실험결과를 이용 해석코드인 RELAP5/MOD3의 평가능력에 대하여 해석을 수행하였다. 해석결과 코드는 사고 초기의 누설량 예측을 제외하고는 일반적으로 실험결과와 잘 일치하고 있음을 보였다.

• 한국방사선학회논문지
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• 제11권1호
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• pp.19-25
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• 2017

본 연구는 부산광역시 거주민을 대상으로 원전주변 갑상선암 논란에 따른 원자력에 대한 전반적 인식을 분석하기 위해 위험도, 발전방식에 대한 선호도 및 경제성, 사전-사후 원자력에 대한 인식 등을 조사하였다. 그 결과, 원전 주변 갑상선암 논란을 계기로 국민들의 원자력에 대한 인식에 변화가 있는 것으로 나타났으며, 특히 사건 이전과 비교하여 위험성 요인에서 가장 큰 폭의 상승을 보였다(p<0.05). 이러한 원자력 위험성에 대한 부정적 인식은 집단의 차이에 의해 다르게 표출되는 것으로 분석되었다. 이는 과학적이고 객관적인 근거에 입각하기보다는 개인마다 상이한 선행경험이나 다른 사람과의 상호작용을 통해 획득한 정보에 기인하는 것으로 판단된다. 향후 국민들의 수준을 고려한 원자력 정책을 수립하기 위해서는 국민들의 원자력에 대한 태도와 견해를 이해하려는 노력과 무엇보다도 원자력에 대한 과학적 신뢰가 보장되어야 할 것으로 사료된다.

• Journal of Radiation Protection and Research
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• 제42권4호
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• pp.222-228
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• 2017

Background: On June 18, 2017, Korea's first commercial nuclear reactor, the Kori Nuclear Power Plant No. 1, was permanently suspended, and the capacity of nuclear power generation facilities will be adjusted according to the governments denuclearization policy. In these circumstances, it is necessary to assess the quality of radiation safety management in nuclear power plants in Korea by evaluating the radiation dose associated with them. Materials and Methods: The average annual radiation dose per unit, the annual radiation dose per person, and the annual dose distribution were analyzed using the radiation dose database of nuclear reactors for the last 5 years. The results of our analysis were compared to the specifications of the Nuclear Safety Act and Medical Law in Korea. Results and Discussion: The annual average per unit radiation dose of global major nuclear power generation was 720 man-mSv, while that of Korea's nuclear power plants was 374 manmSv. No workers exceeded 50 mSv per year or 100 mSv in 5 years. The individual radiation dose according to occupational exposure was 0.59 mSv for nuclear workers, 1.77 mSv for non-destructive workers, and 0.8 mSv for diagnostic radiologists. Conclusion: The radiation safety management of nuclear power plants in Korea has achieved the best outcomes worldwide, which is considered to be the result of the as-low-as-reasonably-achievable (ALARA) approach and strict radiation safety management. Moreover, the occupational exposures were also very low.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2003년도 추계학술대회 및 정기총회
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• pp.159-164
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• 2003

DCS (Distributed Control System) is adapted in the most fossil power plant in our country but that is not true in the nuclear power plant (NPP) because of the safety problem. KEPRI has developed many simulators for the training of the operators working in power plants. With this accumulated high technology we are developing a DCS simulator for the performance verification of the developed DCS for the make-up demin-water treatment system of Kori #3&4. In this paper we explain how we develop the system model and show a simulation result.

• Nuclear Engineering and Technology
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• 제30권4호
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• pp.308-317
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• 1998

Ensuring occupational radiation exposure(ORE) as low as is reasonably achievable(ALARA) has been one of very important requirements in a nuclear power plant. It is well known that about 70 percent of occupational dose has incurred from maintenance jobs in the outage period. To reduce occupational dose effectively, the high-dose jobs in the outage period should be identified with their dose reduction potentials and methods. In this study, a PC-based ORE database program, INSTORE, is developed to evaluate ORE doses in individual jobs, and the ORE data of Kori Units 3 and 4 are assembled to the database. Based on customary job classification, radiation work is classified into 26 main jobs which comprise 61 detailed jobs, and occupational doses are assessed according to each detailed job. As a result, high-dose jobs are identified with dose reduction priority in terms of collective ORE dose. It is recommended that adeqaute dose reduction methods for these jobs should be prepared to improve their working conditions and procedures.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6297-6304
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• 2015

우리나라 최초의 원자력발전소인 고리 원전 1호기의 폐쇄가 결정됨에 따라 원전 해체가 화두가 되고 있다. 원전 해체는 우리나라에서 한번도 경험해 보지 못한 일로 해체 과정도 어렵고 시간도 많이 소요된다. 그 일부분인 해체물량 또한 파악이 어렵다. 본 연구에서는 최근 건설산업에 많이 활용되고 있는 BIM 기술을 원전 해체 물량산출에 활용할 수 있는 방안을 제시하였다. 그 결과, 원전 해체 공법선정 및 공정 확립, BIM 모델링 환경 준비, 작업분류체계 구축, 객체분류체계 구축, BIM 통합모델 작성, BIM 객체에 물량 속성 배분 등의 방안을 제시하였다. 제시한 방안은 영구정지 대상 원전이 집중적으로 발생하는 시기부터 유용하게 활용될 수 있다. 이에 기반한 기술확보를 통해 나아가 해외 원전 해체 사업 수주에도 유리하게 작용할 것으로 기대된다.

• 산업경영시스템학회지
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• 제34권3호
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• pp.79-89
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• 2011

Since commercial operation of Kori-1 nuclear power plant in 1978, twenty units are under operation and six units are under construction at 2011 present. Nuclear power become a main energy source in our country. However, the plant was constructed by a USA vendor in its beginning period, the Quality Assurance requirements of USA was applied. Even though Quality Assurance requirements were newly established to the Korea Atomic Energy Act, its contents are quite similar to those of USA. And 10 CFR 50 App.B, ASME NQA-1 apply to most of nuclear industries as a quality assurance plan. In this paper, Quality Assurance requirement of domestic nuclear industries has been investigated and applicable method of ISO Quality Assurance application to the nuclear industries is suggested by a comparison ISO 9000 and nuclear quality assurance specification.