• 한국지진공학회논문집
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• 제14권1호
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• pp.35-42
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• 2010

한반도의 Gutenberg-Richter b값에 관한 기존 국내 연구결과로부터 최적값을 전문가 패널을 통해 도출하였다. 전문가 패널에 의한 평가 결과, Gutenberg-Richter b값은 지진원 구역에 상관없이 한반도 전체에 걸쳐 비교적 일정하며 그의 평균값은 0.96으로 추천되었다. 지진지체구조는 4가지로 의견이 수렴되었다. 패널평가 결과를 신울진 1.2호기 원전부지에 적용하여 지진재해도에 미치는 영향을 분석하였다. 연구대상 부지의 평균재해도 수준은 전문가 패널평가결과 적용 이전에 비해 0.2g에서 최소 약 70-80% (0.6-0.7 order) 감소하였고, 지진재해도의 불확실성 폭은 0.2g (15%-85% 신뢰구간)에서 현저하게 감소하였다. 향후, 지진재해도분석 시 b값을 지진원 전체에 균일하게 보수적으로 0.95를 적용할 것을 제안하였다.

• 한국공작기계학회논문집
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• 제15권5호
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• pp.104-113
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• 2006

The main objective of this study is to investigate the effect of compounded welding by using acoustic emission (AE) signals and doing a source location for weld heat affected zone (HAZ) through tensile testing. This study was carried out an SWS 490A high strength steel for electric shield metal arc welding, SMAW; $CO_2$ gas metal arc welding, GMAW($CO_2$); and gas tungsten arc welding, GTAW/TIG. Data displays are based on the measured parameters of the AE signals, along with environmental variables such as time and load. For instance, Gutenberg-Richter magnitude-frequency relationship (G-R MFR) offers useful b-value in data analysis. Namely event identification, source location gives the X- and Y-coordinates of the AE source. And K-means clustering analysis by Euclidean distance confirmed that was powerful to source location. Generally, strength of welded metal zone was stronger than strength of base metal. As the result, confirmed certainly that fracture is produced in HAZ instead of welded metal zone from source location.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.64-71
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• 1999

Seismicity of the Korean Peninsula shows intraplate seismicity that has irregular pattern in both time and space. Seismic data of the Korean peninsula consists of historical earthquakes and instrumental earthquakes. In this study we devide these data into complete part and incomplete part and considering earthquake size uncertainty estimate seismic hazard parameters - activity rate λ, b value of Gutenberg-Richter relation and maximum possible earthquake IMAX by statistical method in each major tectonic provinces. These estimated values are expected to be important input parameters in probabilistic seismic hazard analysis and evaluation of design earthquake.

• 지질공학
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• 제8권2호
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• pp.99-114
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• 1998

양산단층계는 한반도의 동남부에 위치한 백악기 경상분지내의 주요한 구조대로서 지금까지 많은 역사지진의 기록이 남아있으며 최근에 북부, 중부, 남부의 세 구역으로 나뉘어질 가능성이 시사된 바도 있다. 서기 2년부터 1997년까지 양산단층의 주변에서 발생한 지진자료를 조선시대 이전의 불완전한 자료와 그 이후의 완전한 자료로 구분하여 최우도 방법을 적용하여 단층 전체와 각 지진구역에 대하여 지진발생률, 규모-빈도 관계의 b값, 최대가능규모 등의 지진활동 매개변수들을 결정하였다. 그 결과 양산단층의 지진활동은 각각의 구역에 따라 많은 차이를 보임을 알 수 있었으며 단층 전체에 대한 b값은 대략 0.85로 나타났다. 북부, 중부 및 남부구역에 대한 최대 가능규모는 각각 5.2, 6.8 6.0으로 나타났으며 이들의 재래주기는 1000년을 초과하는 것으로 나타났다. 또한 각각의 지진구역 및 전 단층대에 대하여 지진자료의 규모-빈도 관계식을 분석하여 지진 발생모델 중 Gutenberg-Richter 모델과 특성지진모델에 대한 적합성을 검증하였다. 이 결과 양산단층의 지진활동은 Gutenberg-Richter 모델보다 특성지진모델에 적합한 모양임을 알 수 있었으나 각각의 구역에 대한 검증은 자료가 부족한 관계로 의미있는 결과를 얻지 못하였다.

• Nuclear Engineering and Technology
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• 제41권10호
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• pp.1223-1234
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• 2009

The outlines of seismic PSA implementation standards and seismic hazard evaluation procedure were shown. An overview of the cause investigation of seismic motion amplification on the Niigata-ken Chuetsu-oki (NCO) earthquake was also shown. Then, the contents for improving the seismic hazard evaluation methodology based on the lessons learned from the NCO earthquake were described. (1) It is very important to recognize the effectiveness of a fault model on the detail seismic hazard evaluation for the near seismic source through the cause investigation of the NCO earthquake. (2) In order to perform and proceed with a seismic hazard evaluation, the Japan Nuclear Energy Safety Organization has proposed the framework of the open deliberation rule regarding the treatment of uncertainty which was made so as to be able to utilize a logic tree. (3) The b-value evaluation on the "Stress concentrating zone," which is a high seismic activity around the NCO hypocenter area, should be modified based on the Gutenberg-Richter equation.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.23-30
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• 1998

An estimation of seismic risk parameters by seismic zones of the Korea Peninsula in order to calculate the seismic hazard values using these was erformed. Seven seismic source zones were selected in consideration of seismicity and geology of Korean Peninsula. The seismicity parameters that should be estimated are maximum intensity, activity rate and b value in the Gutenberg - Richter relation. For computation of these parameters, least square method or maximum likelihood method is applied to the earthquake data in two ways; the one for the data without maximum intensity and the other with maximum intensity. Earthquake data since Choseon Dynasty is regarded as complete and estimation of parameters was made for these data using above two ways. And recently, a new method is published that estimate the seismicity parameters using mixed data containing large historical events and recent complete observations. Therefore, this method is applied to the whole earthquake data of the Korean Peninsula. It turns out that the b value computed considering maximum intensity is slightly lower than that computed considering without maximum intensity, and it becomes still lower when the incomplete data prior to Choseon Dynasty is used. In the case of the activity rates, the values obtained without maximum intensity and that with maximum intensity are similar, though they are lower when the incomplete data is used. The values of maximum intensities are usually lower when considering incomplete data. In the seismic source zone including the Yangsan Fault zone, however, the values are higher when considering the incomplete data.