• 대한기계학회논문집A
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• 제26권7호
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• pp.1376-1383
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• 2002

Seismic qualification of the Air Cleaning Units for nuclear power plant Ulchin 5&6 has been performed with the guideline of ASME Section III and IEEE 344 code. By using the structural and geometrical similarity analysis, the three models to be analyzed are condensed into a single model and, at the same time, the excitation forces and other operating loads for each model are encompassed with respect to different loading conditions. As the fundamental frequencies of the structure are found to be less than 33Hz, which is the upper frequency limit of the seismic load, response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the structural and electric stability of the major components, modal analysis theory is adopted to derive the required response spectrum at the component locations. As the all combined stresses obtained from the above procedures are less than allowable stresses and no mechanical or electrical failures are found from the seismic testing, the authors confirm the safety of the nuclear equipments Air Cleaning Units studied in this paper.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.404-409
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• 2001

Seismic qualification of the Air Cleaning Units for nuclear power plant Ulchin 5&6 has been performed with the guideline of ASME Section III and IEEE 344 code. By using the structural and geometrical similarity analysis, the three models to be analyzed is condensed into a single model and, at the same time, the excitation forces and other operating loads for each model are encompassed with respect to different loading conditions. As the fundamental frequencies of the structure are found to be less than 33Hz, which is the upper frequency limit of the seismic load, response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the structural and electric stability of the major components, modal analysis theory is adopted to derive the required response spectrum at the component locations. As the all combined stresses obtained from the above procedures are less than allowable stresses and no mechanical or electrical failures are found from the seismic testing, the authors confirm the safety of the nuclear equipments Air Cleaning Units studied in this paper.

• 한국소음진동공학회논문집
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• 제12권11호
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• pp.856-863
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• 2002

Seismic qualification of the main control board(MCB) for the nuclear power plant Ulchin 5 and 6 has been performed with the guideline of ASME Section III and IEEE 344 code. As the size and weight of the MCB are too large and heavy to excite using the excitation table, finite element analysis is used in order to investigate the dynamic behaviors and structural integrity of the MCB. As the fundamental frequencies of the equipment are found to be less than 33 Hz, which is the upper frequency limit for the dynamic analysis, response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the electrical stability of the major components of the MCB. modal analysis theory has been adopted to derive the required response spectra at the component locations. As the all combined stresses obtained from the above procedures are less than the allowable stresses and no mechanical or electrical failures are found from the seismic testing, the authors can confirm the safety of the nuclear equipment MCB under the given seismic loading conditions.

• 한국기계가공학회지
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• 제17권1호
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• pp.122-129
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• 2018

This study conducted a seismic qualification analysis of small savonius style vertical axis wind turbine(VAWT) using finite element method(FEM). The modal analysis was performed on the wind turbine structure to check the occurrence of resonance caused by the rotation of gearbox and windmill blades. Next, it conducted a seismic response spectrum analysis due to horizontal and vertical seismic load of required response spectrum of safe shutdown earthquake with 5 % damping(RRS/SSE 5%) of KS C IEC 61400 and conducted a static analysis due to deadweight and wind load. The total maximum stress of the VAWT structure was calculated by adding the maximum stresses due to each load case using the square root of the sum of the squares(SRSS) method. Finally, the structural safety of the VAWT structure was verified by comparing the total maximum stress and the allowable stress.

• Nuclear Engineering and Technology
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• 제48권3호
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• pp.831-839
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• 2016

Seismic qualification by test is widely used as a way to show the integrity and functionality of equipment that is related to the overall safety of nuclear power plants. Another means of seismic qualification is by direct integration analysis. Both approaches require a series of time histories as an input. However, in most cases, the possibility of using real earthquake data is limited. Thus, artificial time histories are widely used instead. In many cases, however, response spectra are given. Thus, most of the artificial time histories are generated from the given response spectra. Obtaining the response spectrum from a given time history is straightforward. However, the procedure for generating artificial time histories from a given response spectrum is difficult and complex to understand. Thus, this paper presents a simple time-domain method for generating a time history from a given response spectrum; the method was shown to satisfy conditions derived from nuclear regulatory guidance.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.498-503
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• 2000

A safety-related equipment for use in Nuclear Power Plant should be needed an Equipment Qualification. This paper presents the approach, methods, philosophies, and procedures for qualifying the large squirrel-cage induction electric pump motors for use in ULCHIN 5&6 Nuclear Power Plants. In this paper, the method of qualification is a combination of type test and analysis method, which is composed of Radiation exposure test, Seismic simulation test, Thermal aging analysis for non-metallic materials and Seismic analysis. It is found that the motor performs its safety function with no failure mechanism under postulated service conditions.

• 한국정밀공학회지
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• 제24권6호
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• pp.72-77
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• 2007

A safety-related equipment for the nuclear power plant should be needed an equipment qualification. In this paper, the approach, methods, philosophies, and procedures for qualifying the large squirrel-cage induction electric pump motors for use in ULCHIN 5, 6 Nuclear Power Plants were presented. The method of qualification is a combination of experimental test and analytic method, which is composed of radiation exposure test, seismic simulation test, thermal aging analysis for non-metallic materials, and seismic analysis. The results showed that the motor performed its safety function with no failure mechanism under postulated service conditions.

• 대한기계학회논문집A
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• 제35권1호
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• pp.47-52
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• 2011

이 논문은 내진검증을 수행하기 위한 유한요소 모델의 개발에 대하여 논의한다. 모델개발에 사용된 기기는 미국의 아칸사스 원자력 발전소의 전자기기 함으로써 유한요소해석 모델개발 과정을 보여준다. 증명된 모델은 진동수 50Hz 이하의 모든 주요모드에서 고유진동수가 5% 이내의 정확치를 가져온다. 유한요소모델은 질점질량과 강성도 방법을 사용한 COSMOSM 이라는 소프트웨어를 채용하여 수학적 모델의 eigenvalue 해석 및 동적해석이 수행되었다. 이 모델은 지정된 하중조건에서 AISC에서 규정한 허용응력치 이하를 나타내었다. 이모델에서 얻는 값들은 참고문헌에서 나타내는 내진 규정에 잘 부합하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1211-1211
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• 2007

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1992년도 가을 학술발표회 논문집
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• pp.148-155
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• 1992

A method to verify seismic qualification of the plant protection system cabinet for a nuclear power plant is presented. A finite element model of the cabinet is developed and correlated to the dynamic properties observed during in-situ vibration test of the actual structure. The results of the modal analysis provide insight into the fundamental dynamic properties of the structure. Techniques for verifying structural integrity and operability are exemplified by summarizing response spectrum and time history analyses of the structure.