• 한국지진공학회논문집
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• 제20권3호
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• pp.145-153
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• 2016

Small-size buildings are not designed by professional structural engineers in Korea. Therefore, their seismic performance can not be exactly estimated because their member sizes and reinforcement may be over- or under-designed. A prescriptive design criteria for the small-size buildings exists, but it also provides over-designed structural members since structural analysis is not incorporated, so it is necessary to revise the prescriptive criteria. The goal of this study was to provide an information for the revision, which is seismic performance and capability of small-size reinforced concrete moment frame buildings. For the study, the state of existing small-size reinforce-concrete buildings such as member size and reinforcement was identified by investigating their structural drawings. Then, over-strength, ductility and response modification factor of the small-size reinforced concrete moment frame buildings were estimated by analytical approach along with seismic performance check. The result showed that they possess moderate over-strength and ductility, and may use slightly increased response modification factor.

• 한국구조물진단유지관리공학회 논문집
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• 제15권2호
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• pp.70-78
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• 2011

본 논문은 변형률 계측데이터를 사용하는 신뢰성 및 정확성을 증진된 BWIM(Bridge Weigh-In-Motion) 알고리즘을 개발하고, 이를 교량에 대한 다양한 실험을 통해 검증하고자 하는 것이다. 본 논문에서는 밀도추정함수와 평균보정계수를 이용한 BWIM 알고리즘을 제시한다. 밀도추정함수는 다축하중을 추정할 때 신뢰할 수 있게 적용할 수 있음을 입증하였으며, 평균보정계수는 이론 계산된 모멘트와 계측된 변형률에서 계산한 모멘트 사이의 전반적인 오차를 최소화하기 위해 적용된다. 개발된 알고리즘은 수치예제, 실내모형실험 그리고 다주형 합성교량에 대한 현장실험을 통해 성공적으로 검증하였다.

• Structural Engineering and Mechanics
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• 제50권1호
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• pp.1-17
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• 2014

In this paper, overstrength, ductility and response modification factors are calculated for frames braced with a different type of buckling restrained braces, called reduced yielding segment BRB (Buckling Restrained Brace) in which the length of its yielding part is reduced and placed in one end of the brace element in comparison with conventional BRBs. Forthermore, these factors are calculated for ordinary BRBF and the results are compared. In this regard incremental dynamic analysis (IDA) method is used for studying 17 records of the most known earthquakes happened in the world. To do that, the considered buildings have different stories and two bracing configurations: diagonal and inverted V chevron, the most ordinary configurations of BRBFs. Static pushover analysis, nonlinear incremental dynamic analysis and linear dynamic analysis have been performed using OpenSees software. Considering the results, it can be seen that, overstrength, ductility and response modification factors of this type of BRBF(Buckling Restrained Braced Frame) is greater than those of conventional types and it shows better seismic performance and also eliminates some of conventional BRBF's disadvantages such as low post-yield stiffness.

• Journal of Ginseng Research
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• 제34권4호
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• pp.264-273
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• 2010

While ginseng is reported to have a wide array of applications, there is growing evidence for its indications in diabetes and vascular disease. A clear connection, however, has not been established between ginseng's composition, dose and its targeted efficacy in humans. We therefore developed and initiated the Korean Red Ginseng Clinical Testing Program for diabetes and vascular function which is an efficacy and safety-based clinical screening model for ginseng. The most efficacious sources, ginsenoside profiles, doses, and modes of administration were examined in sequential, acute, followed by long term, randomized-controlled trials to investigate the efficacy and safety profiles. This review discusses the current state of the clinical research of Korean red ginseng program conducted in Toronto, paving the way for the use of clinically selected ginseng and its ginsenoside fractions in the management of diabetes and vascular diseases.

• 한국방재학회 논문집
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• 제8권2호
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• pp.45-49
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• 2008

본 논문에서는 미국 AISC-LRFD기준에서 제시하고 있는 웨브 변단면 I형 보의 탄성 좌굴강도 산정식을 고찰하였다. 미국 AISC-LRFD 기준의 기본 개념은 웨브 변단면 보를 가장 작은 단면과 동일한 크기를 가지면서 길이가 다른 등가 일정단면보로 대치하는 것이다. 또한 비지지 구간에 작용하는 응력 구배와 이웃한 보의 횡방향 구속효과를 고려하기 위하여 수정계수(B)를 적용하고 있다. AISC-LRFD 기준에 제시된 수정계수(B)와 유한요소해석결과와의 비교를 통해 본 논문에서는 수정계수(B)를 산정하기 위한 재 정의된 방법을 제안하였다.

• 한국전산구조공학회논문집
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• 제32권3호
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• pp.149-154
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• 2019

국내 고층 아파트의 구조시스템은 크게 다수의 벽체가 분산적으로 배치되어 있는 내력벽 시스템과 중앙 코어벽 시스템으로 구분할 수 있다. 각각 시스템에 따른 횡방향 거동을 분석하기 위해 본 연구는 국내 고층 아파트 중 대표적인 평면을 갖는 대상 건물을 선정하고, 비선형 정적해석을 수행하여 붕괴메커니즘을 살펴보았다. 비선형 정적해석을 통해 도출된 힘-변위관계로부터 지진응답에 있어서 중요한 요소인 초과강도계수 및 연성도계수를 산정하여 반응수정계수를 평가하였다. 중앙 코어벽 시스템은 연성도는 작지만, 풍하중에 의해 지배되어 초과강도가 크게 산정돼 초과강도계수에 의해 반응수정계수가 산정되었고, 내력벽 시스템은 벽량이 많아 연성도가 크기 때문에 상당힌 큰 반응수정계수가 산정된다.

• 한국전산구조공학회논문집
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• 제25권2호
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• pp.149-154
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• 2012

도로교설계기준 내진설계편은 붕괴방지수준의 확보를 설계절차에 의해 규정하고 있는 반면 기능수행수준의 확보에 대한 요구사항은 명확하게 제시하고 있지 않다. 붕괴방지수준의 확보를 위해 기본적으로 제시된 설계방법은 응답수정계수를 사용하는 스펙트럼해석법으로, 기능수행수준은 설계과정에 적용되는 위험도계수와 응답수정계수에 의해 결정 되어진다. 위험도계수는 교량의 중요도에 따라 단순하게 적용할 수 있으나 중약진지역에서의 응답수정계수 적용은 설계조건에 따라 다른 결과를 갖게 된다. 이 연구에서는 중약진지역의 일반 도로교량을 대상으로 내진설계를 수행하여 기능수행수준의 결정과정을 검토하고, 이 결과를 토대로 기능수행수준의 확보와 관련하여 내진설계편에 보완해야 하는 사항을 제시하였다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 추계 학술발표회논문집
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• pp.231-238
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• 2003

The overstrength factor and the ductility factor are the two important factors that determines response modification factors used in current seismic codes. The objective of this paper is to obtain the overstrength and ductility factors of special concentric braced frames. For this purpose pushover analysis is performed with model structures until the maximum inter-story drift reaches 2.5% of story height. According to the analysis results, the overstrength factors increase as the height of structures decreases and the span length increases. Ductility factors for mid-story structures turns out to be higher than the other structures and span length does not contribute much to ductility factors.

• East Asian mathematical journal
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• 제17권2호
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• pp.217-224
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• 2001

In this paper, we introduce the notion of some modification of given convergence structure and product convergence. Also, we find some properties which hold between the modification associated with a product of convergence structures and the product of modifications associated with the factor convergence structures.

• 한국안전학회지
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• 제24권4호
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• pp.53-58
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• 2009

The importance of process for repair and reinforcement of the bridge is increasing because of the lack of the fatigue load and stress, a lowering of the bridge load carrying capacity owing to impact and oscillation, deterioration on cultivation periods of the bridge, etc. Typically the experimenter values the bridge load carrying capacity by the real rating factor and response modification factor in bridge load rating through static load test and dynamic load test. But the error occurred in reliability of response modification factor in bridge load rating according to experience of experimenter. so tests of connecting probability theory and valuation of the bridge recently. The study is to compute the real load carrying capacity of the bridge and the rating factor and response modification factor on grade of the bridge, and calculate the probability of over-loaded truck load from Weigh In Motion(WIM) Data in FORTRAN programming applying to Monte-Carlo Simulation. At the result of this study, it is acquired that the new grade is computed for the probability of over-loaded truck load and surface inspection. The A grade is over 1.95, B grade is $1.55{\sim}1.94$, C grade is $1.26{\sim}1.54$, D grade is $1.14{\sim}1.25$, E grade is under 1.13 of rating factor, respectively.