• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.856-861
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• 2010

In recent days, the safety of the levee has been an issue because the levee has become bigger according to the Four-river Restoration Project and so on. The greater part of the levee damage has occurred in the interface between soils and the structures. Specially, the drainage construction crosses the levee keeps its settlement down in order to secure a grade of drainage. However, when the settlement isn't generated by using foundation such as pile, the levee is more likely to have leakage at the interface because the construction doesn't behave with soils. In our study, therefor, testing of the behavior of the levee having the drainage construction was carried out to clarify the effects of the foundation type of drainage construction.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1050-1055
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• 2007

In the case of a rail road bridge extension work, especially single track to double track, the foundation of new substructure which supports the extended part of superstructure could be interfered by the exist foundation of an old bridge. When these two foundations are jointed to prevent such fatal effects of the structure as unequal subsidence of soil foundations, it is important to prove the structural behaviour of the joining surfaces between new foundation and old foundation. 3-Dimensional Finite Element Analysis Method have been studied for the solutions of the structural behaviour of the foundations. In this analysis, 'Contact Element' which allows the sliding of each adjoining member is used for the joint of the boundary surface of the old and new pier foundations. Furthermore, Material Nonlinear Behaviour Analysis also supports the accuracy of the result in this study because the foundations consist of concrete main bodies and reinforced steel bars. These detailed analyses secure the verification of the structural safety of the foundations in the extension work more firmly.

• Geomechanics and Engineering
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• 제20권4호
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• pp.323-331
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• 2020

Pile foundation is widely used for railway bridges in loess throughout northwestern China. Modeling of the loess-pile interaction is an essential part for seismic analysis of bridge with pile foundation at seismically active regions. A quasi-static test is carried out to investigate the hysteretic behaviors of pile foundation in collapsible loess. The failure characteristics of the bridge pile-loess system under the cyclic lateral loading are summarized. From the test results, the energy dissipation, stiffness degradation and ductility of the pile foundation in loess are analyzed. Therefore, a bilinear model with stiffness degradation is recommended for the nonlinearity of the bridge pier-pile-loess system. It can be found that the stiffness of the bridge pier-pile-loess system decreases quickly in the initial stage, and then becomes more slowly with the increase of the displacement ductility. The equivalent viscous damping ratio is defined as the ratio of the dissipated energy in one cycle of hysteresis curves and increases with the lateral displacement.

• 한국농공학회지
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• 제36권1호
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• pp.83-94
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• 1994

The first part of this study dealt with the determination of soil parameters for Lade's double work-hardening model using the raw data obtained from cubical and cylinderal triaxial tests At present, it should be investigated which test can simulated satisfactorily the behavior of soft clayey foundation. In this regard, plate bearing test on the 2-dimentional model foundation(218cm long, 40cm wide, 19&m high) was performed, and finite element analysis carried out to abtain the behavior of the foundation. Settlement, lateral displacement, displacement vector and mode of failure were measured and these values were compared with numerical values in order to validate the numerical program developed by authors. The FEM technique was based on Christain-Boehmer's method, in which the displacement is obtained at each nodal point while stress and pore water pressure at each element.In this research, Biot's equation, which explains was elahorately the phisical meaning of consolidation, was selected, as a governing equation, coupled with Lade's double surface work-hardening constitutive model.

• 헤리티지:역사와 과학
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• 제42권2호
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• pp.110-133
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• 2009

본 연구는 건축학적 관점에서 고대건축의 기초부에 대한 고찰을 하기 위하여 건축유구의 확인이 가능한 백제 및 신라의 사찰유적을 중심으로 초석형태와 초석을 정치시키기 위한 적심, 하부기초의 유형과 시기적 변천의 과정을 살펴보고, 백제와 신라의 건물성격에 따른 기초 적심 초석의 시공기법의 차이점을 규명하는 것을 목적으로 하였다. 조사대상으로는 기발굴되었거나 현재 발굴중인 유적가운데 사찰을 중심으로 하였으며, 조사대상은 아니지만 일부 유적의 자료는 참고로 활용하였다. 특히 유구의 직접적인 확인이 불가능한 고구려의 유적은 북한에서의 연구자료를 참고자료로 활용하였다. 현지확인이 가능한 유적은 현지조사를 통하여 자료를 수집하였으며, 정비 등으로 현지 확인이 불가능한 경우는 발굴보고서를 바탕으로 조사하였다. 조사 후, 각 유적에서 사용된 초석 및 그 하부의 적심과 기초를 각 유형별로 정리 분류하고 이를 시기별 사용건물별로 변천과정을 고찰하였으며, 유형 및 건물성격에 따른 특성과 백제 신라의 건축기법을 비교 고찰하였다. 그 결과 백제와 신라는 기초, 적심, 초석의 사용에 있어서 서로 차이를 보이며, 또한 그러한 차이점을 통하여 황룡사의 목탑이외의 건물에서도 백제건축기술이 사용되었을 가능성을 살펴볼 수 있었다. 이러한 연구결과는 비교적 성격을 명확히 파악할 수 있는 소수의 유적만을 대상으로 고찰된 것으로 향후 보다 많은 건축유적의 발굴성과에 따라 축적되는 자료들을 통해 지속적으로 보완되어야 할 것이다.

• 아동학회지
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• 제22권2호
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• pp.15-28
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• 2001

This study investigated the effectiveness of the Empowering Parents Training(EPT) program of the Settling Life Foundation on the improvement of children's basic life habits, a parent education program. The subjects were 72 mothers of 3- to 6-year-old children in 2 kindergartens located in Yangchun-gu and Nowon-gu in the City of Seoul. There were 36 mothers each in the experimental group and the control group. The mothers in the experimental group took part in a $2{\frac{1}{2}}$ hour Settling Life Foundation program in 4 sessions. The results revealed differences between the experimental and control groups in children's basic life habits. Mothers taking part in the program showed very positive reactions.

• 한국수산과학회지
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• 제20권4호
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• pp.370-378
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• 1987

Wave reflection control functions of mound for the foundation of composite and perforated break-waters were investigated through the theoretical considerations. The theory developed is based on a simple summation of components of reflected waves. The applicability of the theory is assured by the comparative studies of the theoretical calculation and experimental data on the sea surface elevation in front of a breakwater. It is found that the reflection is mainly controlled by depth and width of the mound. In the design of composite type perforated breakwaters, the width of perforated part of the upright section can be decreased to less than half of the conventional design width for the same reflection by using the reflection control function of mound part and the reflection can be reduced until less than $30\%$ of that in the composite breakwaters. Using the results, a design method of mounds is proposed, by which the reduction of wave reflection is assured under the given wave conditions.

• 한국농공학회지
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• 제24권3호
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• pp.73-83
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• 1982

study aims to derive a rational method for the analysis of the farm silo supported on an elastic foundation in which it is assumed that the reaction pressure of the soil at a point is proportional to the deflection at that point. In order to investigate the effects of an elastic foundation on the behaviour of the structures on it, the analysis of the farm silo resting on an elastic foundation was compared with the solution that the ground support may be assumed uniform (which was obtained from part I of this paper). To calculate the deformation of an elastic foundation, Boussinesq's solution which allows an interaction of the various parts of ground was adopted. In this case, the foundation was treated as a superparametric element additionally. In the evaluation of an element stiffness matrix, Gauss quadrature' was used. In above numerical integration, 3-point rule for the farm silo wall and the footing was introduced and 2-point rule for the evaluation of a reaction between the footing and the elastic foundation was adopted. The stresses of a farm silo on an elastic foundation were smaller than those which the distribution of contact pressure between the footing and the soil is assumed uniformly. Since the differences of stresses were remarkable in PS structures than RC structures, it is desirable that designers take into account the effect of an elastic foundation for the case of PS structures. It can be noted that while the effect of an elastic foundation was more conspicuously observed in near of the ground, the value of stresses at far from the soil was little affected by an supported soil.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.192-200
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• 2010

Korea is part of a region of low or moderate seismic zone in which few earthquakes have been monitored, so it is difficult to approve design ground motions and seismic responses on structures from response spectrum. In this study, a series of dynamic centrifuge model tests for demonstrating seismic amplification characteristics in soil-foundation-structure system were performed using electro-hydraulic shaking table mounted on the KOCED 5.0 m radius beam centrifuge at KAIST in Korea. The soil model were prepared by raining dry sand and $V_S$ profiles were determined by performing bender element tests before shaking. The foundation types used in this study are shallow embedded foundation and deep basement fixed on the bottom. Total 7 building structures were used and the response of building structures were compared with response spectrum from the acceleration records on surface.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1302-1305
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• 2003

In this paper we analyzed the effect of compliance mismatch with respect to the thickness variation of elastic foundation(fatty tissue) in end-to-end anastomosis. This study considered the preliminary deformed shape induced by suturing in the anastomosis of coronary artery and PTFE with different diameters using simplified suturing model and the fatty tissue surrounding heart and coronary artery for more accurate result using finite element method. Area compliance(C$\sub$A/) was used to analyze the final deformed shape of the anastomotic part with respect to the thickness variation of fatty tissue under mean blood pressure, 100 mmHg(13.3kPa). The results obtained were as follows : 1. When the elastic foundation, assumed to be incompressive material, surrounded the grafts in anastomosis, the compliance mismatch of artery and PTFE was improved by 47∼72%. 2. As the initial diameter ratio(R$\sub$I/) became larger, the higher difference of compliance was induced in spite of elastic foundation surrounding grafts.