• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.3
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• pp.235-245
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• 2002

The purpose of this study is to figure out the tendency of tunnel convergence during excavation and to present a methodology for the prediction of a fault zone ahead of a tunnel face by analyzing three dimensional displacements in various ways. 3-D numerical analysis was performed to investigate changes of tunnel convergence vectors near a fault zone and to propose a flow chart for predicting fault zones. Results of the site investigation and results of trend line analysis of in-situ data were compared to verify the usefulness of a trend line analysis. It is concluded that the orientation of faults can be predicted by using stereonets and the direction of initial stresses can be predicted from the arm length of a displacement vector as a tunnel approaches fault zones. The results of the trend line analysis coincided with those of the site investigation, and a methodology for the prediction of a fault zone was proposed.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.45-52
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• 2010

One of the ways to minimize damage by a slope collapse is to set up preventive measures in advance by measuring displacements in a slope and predicting a collapse. There have been many different technologies developed to predict a collapse with diverse measuring equipment. Especially recently, attempts have been made to utilize terrestrial LiDAR, a high-tech imaging equipment to measure displacements on a scope. Terrestrial LiDAR generates three-dimensional information about an object with millimeter-level accuracy from hundreds of meters away and has been used in an array of fields including restoration of cultural assets, three-dimensional modeling, and making of topographic maps. In recent years, it has been used to measure displacements in structure as well. This study monitored displacements in slopes of high collapse risk with terrestrial LiDAR. As a result, it was able to confirm the applicability of terrestrial LiDAR to the field, and proposed monitoring methods.

• Journal of the Korean Geosynthetics Society
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• v.21 no.3
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• pp.71-78
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• 2022

In this study, the applicability of underground displacement sensors was considered through rock blasting tests to develop a relatively inexpensive and efficient slope failure prediction system that can quickly detect the risk of slope failure in advance and issue predictions and warnings with accurate judgment. In the blasting experiment, the sensor located close to the blasting source showed a large displacement due to crushing inside the rock and the sensor located away from the blasting source showed a relatively small strain. This study confirmed that the wired and wireless type underground displacement sensor system can be applied to measure the behavior of the rock slope, and it can be used as a basic data for establishing an early warning system to predict slope failure.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.2
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• pp.87-99
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• 2023

Ground excavation inevitably causes ground displacement of adjacent ground, and structures and facilities exposed to ground displacement may suffer various damages. Therefore, in order to minimize the damage and damage to adjacent structures and facilities caused by excavation, ground displacement (settlement and horizontal displacement) in the adjacent ground caused by excavation must first be predicted. There is many ground displacement information induced by general braced cut excavation, but the information is not enough for circular shaft excavation. This study aims to provide information on the estimation of ground settlement caused by circular shaft excavation through the case analysis of circular shafts and comparison with braced cut excavation. From this study, it was found that the use of the settlement criterion of braced cut excavation as the settlement management criterion for circular shaft excavation is a conservative approach in terms of safety. But when considering the economic aspect, it may result in overdesign of the wall and therefore, a more reasonable settlement criterion can be needed for circular shaft excavation.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1290-1291
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• 2011

본 연구에서는 배선용차단기의 트립부 동작 신뢰성 향상과 트립부의 구조 최적화를 위하여 트립부 동작 특성을 정량적으로 예측할 수 있는 자계-동역학 연성해석기술을 연구하였다. 먼저 전류와 트립부 가동자 변위에 따라 가동자에 유기되는 전자기력을 예측할 수 있는 수식을 도출하였으며, 전자기력 수식과 가동자의 회전운동방정식을 시간에 따라 과도해석하여 가동자의 변위와 동작전류, 트립하중을 정량적으로 예측할 수 있는 트립부 동특성 해석기술을 개발하였다. 그리고 개발된 해석기술을 검증하기 위하여 양산 배선용차단기를 이용하여 트립실험을 실시하였으며 동작전류의 실험값과 해석값이 비교적 일치함을 확인하였다. 또한 본 연구에서는 개발된 해석기술의 활용성을 제고하기 위하여 윈도우즈 환경의 트립부 동특성 해석 프로그램을 개발하였으며, 이를 활용하여 트립부 설계변수별 동작 특성을 분석하였다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.2
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• pp.338-347
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• 2005

In this paper, a decimation-in-time search direction algorithm for displacement prediction of moving object is proposed. The initialization of the proposed algorithm for moving direction prediction is performed by detecting moving objects at sequential frames and by obtaining a moving angle and a moving distance. A moving direction of the moving object at current frame is obtained by applying the decimation-in-time search direction mask. The decimation-in-tine search direction mask is that the moving object is detected by thinning out frames among the sequential frames, and the moving direction of the moving object is predicted by the search mask which is decided by obtaining the moving angle of the moving object in the 8 directions. to examine the propriety of the proposed algorithm, velocities of a driving car are measured and tracked, and to evaluate the efficiency, the proposed algorithm is compared to the full search algorithm. The evaluated results show that the number of displacement search times is reduced up to 91.8$\%$ on the average in the proposed algorithm, and the processing time of the tracking is 32.1ms on the average.

• Journal of the Korean GEO-environmental Society
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• v.7 no.3
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• pp.77-83
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• 2006

The purpose of this study is to analyze lateral displacement behavior of clay layers in case of the banking in soft ground through model tests. Seven model tests varying with thickness of soft clay and loading velocity are performed to correlate between ground heaving and loading velocity. In case of low loading velocity, vertical settlement below loading plate and small ground heaving are obviously observed. In case of the high loading velocity, it is shown that both soil displacement at the end of a loading plate and surface heaving are large. In addition, the calculated displacements show good agreement with three cases of field measurements in clay with high moisture contents so that we can predict the range of heaving area and the amount of heaving.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.123-133
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• 2004

The magnitudes of wall thrust acting on quay walls can easily vary due to the development of excess pore pressure in backfill. In this research, a new displacement model was proposed to predict the displacement of the wall considering such magnitude variations of the wall thrust. This model is based on Newmark sliding block concept. The magnitude variation of the wall thrust is modelled by varying the magnitude of yield acceleration. The parametric study was performed to analyze the effects of input parameters on the seismic displacement of the wall, and the validity of this model was verified by comparing its predicted displacements with those of Is shaking table tests.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.07a
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• pp.137-139
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• 2021

본 논문에서는 목조 문화재 영상에서의 변위를 효율적으로 감지하기 위한 객체 중심 증강 기법을 사용한 모델을 제안한다. 우선 객체 중심 증강 기법을 적용하여 변위 객체들이 이미지 공간상의 어느 곳이든 위치할 수 있게끔 데이터를 구성한 이후 사전 학습된 합성 곱 신경망을 사용하여 입력 이미지에 대한 심층 특징 벡터를 추출한다. 그 이후 심층 특징 벡터는 완전 연결 계층의 입력 값으로 들어와서 최종적으로 변위가 존재하는지 아닌지에 대한 예측을 수행하게 된다. 데이터 셋으로는 충주시 근처의 문화재에 방문해서 수집한 목조 문화재 이미지를 가지고 정상 및 비정상으로 구분한 데이터 셋을 사용하였다. 실험 결과 우리가 제안한 객체 중심 증강 기법을 사용한 모델이 객체 중심 증강 기법을 사용하지 않은 모델보다 목조 문화재에서 변위 영역을 더 잘 감지함을 확인하였다. 이러한 결과로부터 우리가 제안한 방법이 목재 문화재의 변위 검출에 있어서 매우 적합함을 보여준다.

• Journal of the Korean Geotechnical Society
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• v.21 no.10
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• pp.99-112
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• 2005

The ground excavation in the urban area induces in general ground movement and subsequent damage on the adjacent building structures. So the essentials in the designing stage are the prediction of ground movement induced by the ground excavation and the damage risk assessment of buildings adjacent to the excavation. A propsed prediction method of the ground movement induced by the strutted excavation has been studied with due consideration of the existing ground movement prediction methods. A building damage risk assessment method based on the angular distortion and the horizontal strain derived from the green-field ground movement is also proposed. These methods have been applied successfully in the on-going deep excavation project in Singapore.