• 대한토목학회논문집
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• 제39권6호
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• pp.821-831
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• 2019

9.12지진(2016.9.12., M_L=5.8)과 포항지진(2017.11.15., M_L=5.4)은 사회·경제적 피해를 야기시켰고, 이로 인해 지진에 대한 국민의 관심이 과거보다 크게 높아졌다. 지진 빈도가 높은 미국, 일본, 칠레 등 불의 고리 인근의 국가에서는 이미 지진재난에 대비·대응을 위하여 지진재해도(PSHA), 지반운동예측모델(GMPE) 등을 기반으로 인프라 시설을 관리하고 있다. 국내도 앞서 설명된 PSHA, GMPE가 개별 연구자들을 통해 독자적으로 개발되고 있지만, 모델 개발시 생성한 기초 데이터 산출 방법, 최종 결과물의 주요 요소 등이 제한적으로 공개되었다. 이는 해마다 발생하는 지진의 추가를 통한 모델 개선이 아닌 과거 지진에 대해 매번 새롭게 자료 구축을 해야 한다는 문제점을 내포하고 있다. 따라서, 본 연구에서는 GMPE 개발의 기초자료인 플랫파일 생성 방법과 지진 관측자료의 지진파형의 계기보정 방법, 계기진도 생성 방법 등을 기술하였다.

• Earthquakes and Structures
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• 제10권2호
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• pp.389-408
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• 2016

Recently, seismic hazard analysis has become a very significant issue. New systems and available data have been also developed that could help scientists to explain the earthquakes phenomena and its physics. Scientists have begun to accept the role of uncertainty in earthquake issues and seismic hazard analysis. However, handling the existing uncertainty is still an important problem and lack of data causes difficulties in precisely quantifying uncertainty. Ground Motion Prediction Equation (GMPE) values are usually obtained in a statistical method: regression analysis. Each of these GMPEs uses the preliminary data of the selected earthquake. In this paper, a new fuzzy method was proposed to select suitable GMPE at every intensity (earthquake magnitude) and distance (site distance to fault) according to preliminary data aggregation in their area using ${\alpha}$ cut. The results showed that the use of this method as a GMPE could make a significant difference in probabilistic seismic hazard analysis (PSHA) results instead of selecting one equation or using logic tree. Also, a practical example of this new method was described in Iran as one of the world's earthquake-prone areas.

• 한국수자원학회논문집
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• 제53권9호
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• pp.661-670
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• 2020

최근 지진재해의 규모가 점차 증대됨에 따라 세계적으로 개별 시설물에 대한 내진성능평가와 관련한 연구가 다수 진행되고 있다. 상수도 시스템은 타 기반 시설에 비해 설치범위가 광범위하고 그 구성요소가 다양해 고려할 것이 많아 지진에 대한 안정성을 정확하고 효과적으로 확보하기 힘든 실정이다. 따라서 지진을 대비한 상수도 시스템의 내진성능 평가 방안을 연구하고 개발할 필요가 있다. 지진에 의한 상수도 시스템의 내진성능을 평가하기 위해 지반운동예측식(Ground Motion Prediction Equation, GMPE)이 활용된다. GMPE는 지진 규모 등과 같은 독립변수 와 PGV (Peak Ground Velocity), PGA (Peak Ground Acceleration)와 같은 지반운동 등을 고려하여 산정하게 된다. 우리나라에서 발생된 높은 강도의 지진 데이터는 현재까지 많이 축적되지 않아 특정 지진에 국한된 데이터를 활용하여 GMPE를 결정하는 등의 연구가 진행되었다. 본 연구에서는 우리나라에서 계측된 지진 데이터를 활용하여 국내 지진 모의에 적합한 GMPE를 선정하고자 하였으며, 이를 위해 기존 국내 지진을 기반으로 산정된 GMPE식을 분석하고 그 결과를 제시하였다. 본 연구를 통해 결정된 적정 GMPE는 상수도관망의 수리학적 내진성능 평가에 직접적으로 활용 가능하다. 즉, 파손확률 모형과의 연계를 통한 지진시 관로 파손률의 정량화가 가능하며, 파손 및 누수에 의한 단수지역 파악 등과 같은 피해범위 산정시 보다 객관적이며 합리적인 결과 도출이 가능하다. 최종적으로 이와 같은 내진 성능 정량화 결과는 지진재해가 발생하였을 경우 그 피해를 최소화할 수 있는 최적 복구방안 마련과 선제적 관망 내진설계의 기준 자료로 활용될 수 있다.

• Earthquakes and Structures
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• 제15권1호
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• pp.29-44
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• 2018

A ground-motion prediction equation (GMPE) for the Korean Peninsula, especially for South Korea, is developed based on synthetic ground motions generated using a ground motion model derived from instrumental records from 11 recent earthquakes of $M_L$>4.5 in Korea, including the Gyeongju earthquake of Sept. 12. 2016 ($M_L$5.8). PSAs of one standard deviation from the developed GMPE with $M_W$ 6.5 at hypocentral distances of 15 km and 25 km are compared to the design spectrum (soil condition, $S_B$) of the Korean Building Code 2016 (KBC), indicating that: (1) PSAs at short periods around 0.2 sec can be 1.5 times larger than the corresponding KBC PSA, and (2) SD's at periods longer than 2 sec do not exceed 8 cm. Although this comparison of the design spectrum with those of the GMPE developed herein intends to identify the characteristics of the scenario earthquake in a lower-seismicity region such as South Korea, it does not mean that the current design spectrum should be modified accordingly. To develop a design spectrum compatible with the Korean Peninsula, more systematic research using probabilistic seismic hazard analysis is necessary in the future.

• Natural Product Sciences
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• 제22권3호
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• pp.147-153
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• 2016

Inflammation plays an important role in host defense against external stimuli such as infection by pathogen, endotoxin or chemical exposure by the production of the inflammatory mediators that produced by macrophage. Anti-inflammatory factor is important to treat the dangers of chronic inflammation associated with chronic disease. This research aims to analyze the anti-inflammatory effects of Garcinia mangostana L. peel extract (GMPE), ${\alpha}$-mangostin, and ${\gamma}$-mangostin in LPS-induced murine macrophage cell line (RAW 264.7) by inhibiting the production of inflammatory mediators. The cytotoxic assay of G. mangostana L. extract, ${\alpha}$-mangostin, and ${\gamma}$-mangostin were performed by MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) to determine the safe and non-toxic concentration in RAW 264.7 for the further assay. The concentration of inflammatory mediators (COX-2, IL-6, and IL-$1{\beta}$) were measured by the ELISA-based assay and NO by the nitrate/nitrite colorimetric assay in treated LPS-induced RAW 264.7 cells. The inhibitory activity was determined by the reducing concentration of inflammatory mediators in treated LPS-induced RAW 264.7 over the untreated cells. This research revealed that GMPE, ${\alpha}$-mangostin, and ${\gamma}$-mangostin possess the anti-inflammatory effect by reducing COX-2, IL-6, IL-$1{\beta}$, and NO production in LPS-induces RAW 264.7 cells.

• Earthquakes and Structures
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• 제11권5호
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• pp.779-807
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• 2016

Ground Motion Prediction Equations (GMPEs) are essential tools in seismic hazard analysis. With the introduction of probabilistic approaches for the estimation of seismic response of structures, also known as, performance based earthquake engineering framework; new tasks are defined for response spectrum such as the reference criterion for effective structure-specific selection of ground motions for nonlinear time history analysis. One of the recent efforts to introduce a high quality databank of ground motions besides the corresponding selection scheme based on the broadband spectral consistency is the development of SIMBAD (Selected Input Motions for displacement-Based Assessment and Design), which is designed to improve the reliability of spectral values at all natural periods by removing noise with modern proposed approaches. In this paper, a new global GMPE is proposed by using selected ground motions from SIMBAD to improve the reliability of computed spectral shape indicators. To determine regression coefficients, 204 pairs of horizontal components from 35 earthquakes with magnitude ranging from Mw 5 to Mw 7.1 and epicentral distances lower than 40 km selected from SIMBAD are used. The proposed equation is compared with similar models both qualitatively and quantitatively. After the verification of model by several goodness-of-fit measures, the epsilon values as the spectral shape indicator are computed and the validity of available prediction equations for correlation of the pairs of epsilon values is examined. General consistency between predictions by new model and others, especially, in short periods is confirmed, while, at longer periods, there are meaningful differences between normalized residuals and correlation coefficients between pairs of them estimated by new model and those are computed by other empirical equations. A simple collapse assessment example indicate possible improvement in the correlation between collapse capacity and spectral shape indicators (${\varepsilon}$) up to 20% by selection of a more applicable GMPE for calculation of ${\varepsilon}$.

• Earthquakes and Structures
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• 제6권1호
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• pp.1-18
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• 2014

The main focus of this paper is the analysis of the different components of the variability for strong ground motions recorded from earthquakes produced by the Vrancea subcrustal seismic source. The analysis is performed for two ground motion prediction equations: Youngs et al. (1997) and Zhao et al. (2006), recommended within the SHARE project for the Vrancea subcrustal seismic source and which are proposed in the work of Delavaud et al. (2012) and graded best in Vacareanu et al. (2013c). The first phase of the analysis procedure consists of a grading procedure. In the second phase, the single station sigma procedure is applied for both attenuation models in order to reduce some parts of ground motion models' variability produced by the ergodic assumption. The strong ground motion database which is used throughout the study consists of over 400 accelerograms recorded from 9 Vrancea intermediate-depth seismic events. The results of the single station sigma analysis show significant reduction of the standard deviations, especially in the case of the Youngs et al. (1997) attenuation model, which is also graded better than the other selected GMPE.

• Earthquakes and Structures
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• 제7권4호
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• pp.485-510
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• 2014

In performance-based seismic design procedures Peak Ground Acceleration (PGA) and pseudo-Spectral acceleration ($S_a$) are commonly used to predict the response of structures to earthquake. Recently, research has been carried out to evaluate the predictive capability of these standard Intensity Measures (IMs) with respect to different types of structures and Engineering Demand Parameter (EDP) commonly used to measure damage. Efforts have been also spent to propose alternative IMs that are able to improve the results of the response predictions. However, most of these IMs are not usually employed in probabilistic seismic demand analyses because of the lack of reliable Ground Motion Prediction Equations (GMPEs). In order to define seismic hazard and thus to calculate demand hazard curves it is essential, in fact, to establish a GMPE for the earthquake intensity. In the light of this need, new GMPEs are proposed here for the elastic input energy spectra, energy-based intensity measures that have been shown to be good predictors of both structural and non-structural damage for many types of structures. The proposed GMPEs are developed using mixed-effects models by empirical regressions on a large number of strong-motions selected from the NGA database. Parametric analyses are carried out to show the effect of some properties variation, such as fault mechanism, type of soil, earthquake magnitude and distance, on the considered IMs. Results of comparisons between the proposed GMPEs and other from the literature are finally shown.

• 한국지반공학회논문집
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• 제36권10호
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• pp.57-71
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• 2020

본 연구에서는 2017년 11월 15일 포항지진 시 액상화 위험도가 높았던 5개소의 부지에 대해 액상화 가능성을 재분석하였다. 액상화 지진 하중은 포항 지진파를 지반예측운동방정식(Ground motion prediction equation, GMPE)로 산정한 응답스펙트럼에 보정한 결과를 입력 지진파로 사용하였다. 지반의 액상화 저항력은 현장 시험 중 표준관입시험(Standard Penetration Test, SPT)과 콘관입시험(Cone penetration test, CPT)을 통해 결정되었다. 한편, 액상화 발생 가능성은 지반 액상화 지수(LPI)를 통해 정량화되었으며 이를 기존 연구 결과와 비교하였다.

• 한국버섯학회지
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• 제9권1호
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• pp.22-26
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• 2011

국내 재배비중이 가장 높은 큰느타리2호의 단점을 보완하고 버섯의 국내 육성품종 다양화하고 보급을 확대시키기 위해 육성한 "곤지3호"의 주요 품종특성은 다음과 같다. 균사생장적온은 $26{\sim}29^{\circ}C$, 버섯발생 및 생육적온은 $14{\sim}18^{\circ}C$였으며, 배양일수 30일, 초발이소요일수 8일, 생육일수 5일로 전체 생육일수는 46일로 큰느타리2호와 대등하였다. 유효경수는 병당 2.4개, 대굵기 43.7mm, 대길이 123.8mm, 갓직경 64.9mm로 큰느타리2호와 비슷하였지만, 갓표면의 색도에 있어 명도값(L값)이 54.4로 큰느타리2호 58.2보다 낮아 전체 적으로 진회색을 나타내었다. 병당 수량 182g/1100cc 내외로 통계적 유의성은 없었으나 큰느타리2호 보다 높은 경향을 나 타내었다. 자실체의 단단한 정도(경도)는 $7,790g/cm^2$로 큰느타리2호 $5,650g/cm^2$보다 높았고, 탄력성, 씹음성, 탄력성 등 전체적인 물리적 지표들이 큰느타리2호보다 높았다.