• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.234-237
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• 2006

A series of three shear wall specimens was tested under constant axial stress and reversed cyclic lateral loading in order to evaluate the seismic retrofit that had been proposed for the shear wall with the opening induced by remodeling. One of these specimens was tested in the as-built condition and the other two were retrofitted prior to testing. The retrofit involved the use of carbon fiber sheets and steel plates (thickness of 3mm) over the entire face of the wall. The test results show that the ultimate failure modes of the specimens were found to be shear fracture of the wall around the opening and two difference types of retrofitting strategy make the different effects of a rise in the strength of each specimen.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.427-429
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• 2005

This paper presents the use of Point Number Algorithm (PNA) for real-time image processing for position identification of mobile robot. PNA can get how many points in the image gotten from the robot vision and can calculate the distance between the robot and the wall by the number of the points. The algorithm can be applied to a robot vision system enable to identify where it is in the workspace. In the workspace, the walls are made up by white background with many black points on them evenly. The angle of the vision is set invariable. So the more black points in the vision, the longer the distance is from the robot to the wall. But when the robot does not face the wall directly, the number of the black points is different. When the robot faces the wall, the least number of the black points can be gotten. The simulation results are presented at the end of this paper.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1107-1112
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• 2004

For a rigid retaining wall with rough face, the practical shape of failure surface and arching effect in the backfill must be considered to acquire accurate magnitude and non-linear distribution of active earth pressure acting on the rigid retaining wall. In this study, a new formulation for calculating the active earth pressure on a rough rigid retaining wall rotating about the top is proposed considering the practical shape of non-linear failure surface and arching effects. Accuracy of the proposed equation is checked through comparisons of calculations from the proposed equations with existing model test results. The comparisons show that the proposed equations produce satisfactory results.

• 한국지반신소재학회논문집
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• 제5권4호
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• pp.35-42
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• 2006

최대 높이가 29.5m인 고성토 보강토옹벽에 대한 시공 및 계측이 수행되었다. 이와 같이 높은 보강토옹벽에 대한 설계 및 시공 경험이 그다지 많지 않기 때문에, 본 현장에서는 철저한 설계 및 시공관리가 이루어졌다. FHWA 설계기준에 근거하여 본 현장 보강토옹벽의 내적 및 외적안정을 검토하였고, Bishop의 간편법을 이용하여 전반활동에 대한 안정성 해석을 수행하였다. 또한 시공관리 및 안정성 검토를 위한 일련의 현장계측을 수행하였다. 본 논문에서는 높이가 20m 이상이고, 2단으로 시공된 대표단면 2개소에 대한 계측결과를 분석하였다. 계측결과, 벽체 및 보강재의 변형이 매우 작게 측정되었으며, 벽체작용 수평토압 또한 미소한 것으로 나타났다. 따라서 높이가 20m이상으로 매우 높은 옹벽구조물에 있어서, 보강토옹벽공법이 성공적으로 적용될 수 있음을 확인하였고, 또한 시공관리가 잘 이루어질 경우 이같이 높은 보강토옹벽에 대하여 FHWA 설계기준이 매우 보수적인 안전측 결과를 보임을 알 수 있었다.

• 한국지반공학회지:지반
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• 제14권5호
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• pp.67-76
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• 1998

본 연구에서는 보강토 구조물에 이용되는 지오그리드와 국내에 많이 분포하고 있는 화강풍화토를 대상으로 하여, 보강재의 포설깊이가 동일한 상태에서 보강재의 길이를 벽체높이의 0.465배, 0.685배, 0.9배로 설치하여 보강재가 전면벽체에 정착된 경우와 비정착된 경우에 대하여 모형실험을 실시하였다. 모형실험결과, 정착된 경우에는 보강재의 길이가 증가함에 따라 지지력은 무보강인 경우 보다 약 1.725~2.1배 증가함을 알 수 있었으며, 침하량도 약 20%이상의 감소율을 보였다. 전면 벽체의 최대 수평변위량은 무보강에 비해 약 80%이상의 감소율을 보였다. 비정착된 경우에도 무보 강인 경우보다 지지력이 약 1.7배이상 증가하였으며, 전면벽체의 최대 수평변위는 약 50%이상 감소하였다. 모형실험을 통해 고찰한 파괴면은 Bchlosser 등(1979)의 연구결과와 유사하게 나타났다.

• 한국구조물진단유지관리공학회 논문집
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• 제11권4호
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• pp.51-61
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• 2007

건축의 증가나 자원의 효율적인 활용의 관점으로부터 기존 건축물에 대한 리모델링이 주목을 받고 있다. 리모델링 공사로 인해 기존벽에 개구부를 설치하는 경우 보강 방법을 검토 하는 것을 목적으로 철근콘크리트벽의 정적가력 실험을 실시하였다. 보강 방법은 개구부 주위의 탄소섬유시트 강판 부착으로 했다. 실험체는 실존하는 철근콘크리트 구조물을 1/2 축소 모델로 제작하였다. 실험결과 개구부 주위의 전단 파괴로 최종 파괴되었으며 보강 방법에 따라 내력의 상승 효과는 다르게 나타났다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.412-417
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• 2005

To ensure the safety of the tunnelling without the loss of economy, the tunnel seismic profiling(TSP) method for the prediction ahead of tunnel face, begins to be used routinely in these days. TSP method does not interfere the tunnelling works while the horizontal drilling does, and its prediction length is longer than that of the drilling. Yet the most frequently adopted technique of TSP in Korea is the multi-shot and 2 receiver array using in-hole receivers, even though this array requires as many as 26 drill-holes for receiver installation and ballasting, which results in 3-6 hours of suspension in excavation work. In this paper, multi-receiver and lesser shot array using side-wall attached 3 component geophones is to be described to prove the efficiency in terms of the survey time as well as the reliability of the method by comparison of the predicted weak points and the face mapping results. The predictions mostly agreed with the real fractures or joint developed zones which have been confirmed during the excavation. It also has been found that TSP method can be effectively applied to perform draining ground water ahead of tunnel face by imaging the geologic discontinuities.

• 한국지반환경공학회 논문집
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• 제7권6호
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• pp.23-34
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• 2006

본 연구에서는 보강재의 침하를 허용하는 침하형 보강토 옹벽의 거동을 평가하기 위하여 원심모형실험을 수행하였다. 실험결과는 연결부의 침하를 허용하지 않는 일반형 보강토옹벽에 대한 결과와 비교 분석하여 침하형 보강토 옹벽의 안정성을 평가하였다. 모형실험에서 전면판은 알루미늄판을 사용하였으며, 보강재는 알루미늄 호일을 이용하였으며, 뒤채움지반은 화강풍화토를 사용하였다. 실험결과, 침하자유형 보강토옹벽은 80g의 중력수준에서 완전한 파괴상태에 도달하였으며, 일반형 보강토 옹벽이 69g의 중력수준에서 파괴된 것을 감안하면 침하자유형 보강토 옹벽이 안정성이 우수하다는 것을 확인할 수 있었다. 또한, 69g에서 침하자유형 보강토옹벽 저면에서의 수직토압이 일반형에 비해 16% 정도 크게 측정되었다.

• 터널과지하공간
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• 제5권2호
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• pp.95-103
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• 1995

In this paper the stress redistribution around tunnel face was analyzed by using a three-dimensional finite element model. The effects of in-situ stress levels, excavation sequences, stiffness difference between the hard ground and the weak zone on the stress redistributions were considered. Displacement and stress changes at tunnel crown, side wall, and invert were investigated throughout the sequential excavation. To show ground response, percentage of the displacement and stress variations are used as a function of normalized distance that is between the face and monitoring section. Preceding displacements and stress variations were presented to be adopted in the two-dimensional tunnel analysis.

• 건축역사연구
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• 제18권1호
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• pp.31-49
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• 2009

Periodically, the Japanese Castle was created in the domestic of Japan and then 2 Invasions into Chosun was started. The Japanese Castle in the domestic of Japan was repaired several times by the building boom of castle before & after 2 invasions and so the initially-built type of castles was changed. Accordingly, there are much difficulties to understand the original shape of Japanese Castle. Through the Japanese Castle within Korea called as the fossil of Japanese Castle, I would like to examine & consider its building period and characteristics. The terminology called as [Two Side Stone's Wall] is that of castle which is not acknowledged in the Japanese Academic Circles. However, it means the two-fold wall of Japanese Castle which was widely applied to the fortification way in the Age of Japan Edo. The terminology of [Sori] says the stonework curve in the corner of Japanese Castle which is indicated best in the Japanese Castle. It calls the curve as like the fan frame. [Curb Stone's Wall] says the type of castle wall constructed with over 1 face in wall body of Japanese Castle. (1) About classifying the construction period of Japanese Castle, the curb stone's wall and the castle having no two side stone's wall must consider the building period as that of Japanese Invasion of Korea in 1592. If there was [Sori], the two-side stone's wall was used and the place which supported the documentary data, in particular, the place having the record of contraction is considered to be confirmed as the castle constructed in the period of Japanese Invasion of Korea in 1597. (2) The two-side-type stone's wall shown in the Modern Japanese Stone Castle is difficultly considered to be generated from the Japanese Castle at the period of Japanese Invasion of Korea in 1592 and in 1597. (3) The beautiful [Sori] shown in the Modern Japanese Stone Castle was started from the Japanese Castle of Korea at the period of Japanese Invasion of Korea in 1597. It is difficultly considered which its indication was firstly generated by the Chaesung-Folded Segment Structure.