• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.1
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• pp.31-40
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• 2003

Due to the random nature of earthquake, the definition of the input excitation is one of the major uncertainties in the seismic response analysis. Furthermore, ground motions that correspond to a limited number of design parameters are not unique. Consequently, a brood range of response values can be obtained even with a set of motions, which match the same target parameters. The paper presents a practical probabilistic approach that can be used to systematically model the stochastic nature of seismic loading. The new approach is based on energy-based RMS hazard and takes account for the uncertainties of key ground motion parameters. The simulations indicate that the new RMS procedure is particularly useful for the rigorous probabilistic seismic response analysis, since the procedure is suitable for generation of large number of hazard-compatible motions, unlike the conventional procedure that aim to generate a small number of motions.

• Annual Conference of KIPS
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• 2013.05a
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• pp.850-852
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• 2013

산업발전에 따라 초정밀 가공/생산/검사 장비를 설치, 운용하는 FAB. 구조물의 건축이 증대되고 있으며, 이에 따라 건물의 환경진동 규제치도 강화되고 있는 실정이다. 한국은 일본이나 동남아 국가들과는 달리 지진에 대한 피해가 직접적으로 보고되고 있지는 않지만, 동일본 지진에서와 같이 인접국가의 대규모 지진은 초정밀 장비의 작동에 심각한 영향을 준다. 따라서, 본 논문에서는 대규모 지진에 영향을 받는 일반 건물과 미세한 지반 진동에도 영향을 받는 정밀 FAB. 에서 운용이 가능한 범용적인 지진재해 대비 모니터링 시스템의 설계에 대해 서술한다.

• Proceedings of the Korean Reliability Society Conference
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• 2002.06a
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• pp.453-462
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• 2002

자연재해, 인위적인 재해 등 회사경영에 관련해 다양한 리스크 문제가 나타나고 있으며 리스크에 대한 적절한 대응을 하고 안정화를 도모함과 동시에 리스크 문제가 표면화되어 초래하는 영향을 극소화하기 위한 포괄적인 새로운 패러다임의 경영시스템 도입이 주요 전략과제로 대두되고 있다. 본 연구에서는 리스크 위험 요소를 줄이고 품질 향상의 목적으로 기업의 경쟁력 강화를 위한 새로운 모델로써 기존 ISO 9000 품질경영시스템과 JIS Q 2001 리스크 경영시스템의 통합모델을 제시하고자 한다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.817-824
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• 2002

자연재해, 인위적인 재해 등 회사 경영에 관련해 다양한 리스크 문제가 나타나고있으며 리스크에 대한 적절한 대응을 하고 안정화를 도모함과 동시에 리스크 문제가 표면화되어 초래하는 영향을 극소화하기 위한 포괄적인 새로운 패러다임의 경영시스템 도입이 주요 전략과제로 대두되고 있다. 본 연구에서는 리스크 위험 요소를 줄이고 품질 향상의 목적으로 기업의 경쟁력 강화를 위한 새로운 모델로써 기존 ISO 9000 품질경영시스템과 JIS Q2001 리스크 경영시스템의 통합모델을 제시하고자 한다.

• Journal of the Korean Geotechnical Society
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• v.23 no.3
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• pp.111-121
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• 2007

The paper presents a reliability-based method that can capture the impact of uncertainty of seismic loadings. The proposed method incorporates probabilistic concepts into the classical limit equilibrium and the Newmark-type deformation techniques. The risk of damage is then computed by Monte Carlo simulation. Random process and RMS hazard method are introduced to produce seismic motions and also to use them in the seismic slope analyses. The geotechnical variability and sampling errors are also considered. The results of reliability analyses indicate that in a highly seismically active region, characterization of earthquake hazard is the more critical factor, and characterization of soil properties has a relatively small effect on the computed risk of slope failure and excessive slope deformations. The results can be applicable to both circular and non-circular slip surface failure modes.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.2
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• pp.122-134
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• 2020

On the many coasts of South Korea, including the eastern side, it has been recently increasing the coastal disaster such as the severe coastal erosion and road damage swept away by the wave. As one of the alternatives to prevent the coastal disaster, it has been widely studied the coastal disaster reduction method by the Low-Crested Structure (LCS) in the many countries including several European countries. In this study, the olaFLow model is used to simulate the permeable LCS and wave field of the LCS through the three-dimensional irregular waves numerical analysis on the basis of the previous research. From the numerical analysis, it is evaluated the H_rms, nearshore current and time-averaged turbulent kinetic energy. In addition, the pattern of nearshore current and spatial distribution of time-averaged turbulent kinetic energy are compared with the case of submerged breakwater under the irregular wave fields. As one of significant results, it is confirmed that the pattern of nearshore current is different with the case of submerged breakwater.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.5
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• pp.352-365
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• 2012

A primary study on the rapid modeling of storm surge, which is one of typical coastal disasters, for immediate forecasting in conjunction with typhoon advisories is done and tested for the typhoons Bolaven, Tembin and Sanba which attacked to Korean Peninsula on August and September in this year 2012. Semi automatic rapid computations according to JTWC typhoon advisories were performed and uploaded to the web by models SLOSH in PC and ADCIRC in parallel clusters with 64 cores having 57k nodes encompassing the North-Western Pacific region. It only takes 1 and 2 hours from taking advisory to web uploading, respectively. By comparison with observed water surface elevations for the major tidal stations after Bolaven attack it shows within RMS error of 0.17~0.19 m for surge heights and only deviates 1 hour of peak surge time in ADCIRC model. Thus it is concluded that this approach provides a frame of near real-time immediate forecasting of storm surges with satisfactions.

• Journal of the Korean GEO-environmental Society
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• v.14 no.11
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• pp.5-12
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• 2013

The purpose of this study is to estimate the behavior and the mechanism of debris flow at the end of mountain side when a berm was set on the inclined plane. The numerical model was performed by using the Finite Difference Method(FDM) based on the equation for the mass conservation and momentum conservation. In order to measure the behavior of the debris flow, the debris flow of a straight channel slope and the debris flow of channel slope with 3 types of berms were compared. First, the flow discharge and the sediment volume concentration at the downstream of the channel slope, depending on the various berm width and the different inflow discharges at the upstream of the channel were analyzed. The longer the berm width, the flow discharge at the downstream of the channel was decreased and the high flow fluctuation was reduced by a berm. And it means that a berm can effect for the delay of the debris flow. Through Root Mean Square ratio(RMS) comparison, the flow discharge of the channel slope with a berm was lower than that of a straight channel slope. The longer the berm width, for the sediment volume concentration, an inflection point did not show but mild curve. Because the low sediment concentration with water mixture by a berm continuously flow at the downstream end, it will be effect for reducing the disaster caused by debris flow. The results of this study will provide useful information in predicting and preventing disaster caused by the debris flow.