• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.111-111
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• 2015

한 지점의 수문 반응을 결정짓는 주요 인자 중의 하나는 유역의 형상과 유역 내 하계망 구조이다. 유역의 형상과 하계망 구조는 지질시간 규모에 걸쳐 서서히 형성된 것으로, 주로 지반운동, 암석 및 지질구조, 그리고 이에 대응하는 지표 침식 정도에 의해 결정된다. 따라서, 암석 및 지질구조가 균질하다면, 유역의 특성은 지반운동과 지표 침식에 의해 좌우될 것이다. 본 연구는 지반운동의 시간적인 분포가 서로 다른 조건일 때 유역 특성이 각각 어떠한지를 수치지형발달모형(numerical landscape evolution model)을 이용한 모의실험을 통해 이론적으로 탐색해보았다. 구체적으로 모의 기간 동안의 총 지반융기량은 동일하더라도, 융기율이 전 기간동안 동일한 조건, 융기율이 특정 시점에 집중되는 조건, 그리고 융기율이 높았던 때와 낮았던 때가 반복되는 조건 등 세가지 시나리오를 실험하였다. 각 조건에 대해, 유역 형상과 하계망 구조는 어떻게 형성되는지를 살펴본 것이다. 모의결과 유역의 형태와 하계망 구조는 총융기량보다는 융기율의 시간 분포에 결정적인 영향을 받는다는 것을 확인하였다. 또한, 융기율의 시간분포는 유역의 전반적인 경사(하천 종단의 요형도)와 충적하상 및 기반암하상 하도의 분포 등에 큰 영향을 주었다.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.3
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• pp.58-69
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• 2018

This study investigated root damage characteristics and correlations between roadside trees and street furniture through the investigation of the root damage conditions and the current status of roadside trees and street furniture in Seo-gu, Daejeon City where the occurrence of pavement uplift is frequent. The study area was divided into six areas by species of trees as Metasequoia glyptostroboides and Platanus occidentalis focusing on the streets that were installed with trees chest height and 8cm round planted at the time of the development of the Dunsan-dong Housing Site Development in Seo-gu, Daejeon metropolitan city (1990~1994). The damage rate of roadside protection frames (95.3%) was higher than that of curbstones (19.7%) at the study site. Streets without a protective frame were more likely to have damaged pavement. In addition, the frequency of breakage of protective frames was lowered when a drinking water area was increased to more than a certain level. The frequency of the type of uplift in the sidewalk pavement surfaces is in the order of tail type > mounding type > irregular type, and the frequency of the uplift direction is the highest in Direction 1 ($0{\sim}44^{\circ}C$), Direction 2 ($45{\sim}89^{\circ}$), and Direction 3 ($95{\sim}134^{\circ}$) when $180^{\circ}$ of the street direction is based on $90^{\circ}$ parallel to the curbstone. The uplift length is about 31~60cm and it is most often at a height of 3~6cm. When comparing the results of uplift deformation, Metasequoia glyptostroboides was found to be higher than the deformation of Platanus occidentalis. In addition, it can be seen that the larger the length, width and height of the ridge, the larger the deformation becomes. The relationship between the diameter at breast height, the dimension of the pavement width, the frequency of the ridge phenomenon and the deformation amount is not necessarily proportional, and there seems to be a gap due to external factors such as soil humidity and planting base. Therefore there is a need for a multi-directional approach in reducing uplift.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4C
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• pp.137-145
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• 2011

The amount of material upheaved owing to the installation of a granular compaction pile (GCP) in the seabed was analyzed by a field execution. The amount of material upheaved was predicted by existing equations, proposed by the Korea Construction New-Technology Association (KCNET; 2003) and Shiomi and Kawamoto (1986), and compared with the amount measured by bathymetry in the field. As a result, the upheaval heights were found to show a clear increase with increasing replacement ratio. The measured amount was larger than the amount predicted by the equations, but the amount predicted from the equation proposed by KCNET (2003) was relatively close to the measured amount. The upheaval heights were found to be more sensitive to the replacement ratio than the installation depth. The increasing trends of the upheaval heights with the installation depth as predicted by the equation of KCNET (2003) were in agreement with the measured trends at a replacement ratio of 25%. As a result of comparing the coefficients of upheaval by the equations, the coefficients of upheaval determined by the equation of KCNET (2003) were larger than those determined by the equation proposed by Shiomi and Kawamoto (1986), which were relatively close to the measured trends. Specifically, the difference between results obtained by both these equations was large when the replacement ratio was relatively low.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.736-736
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• 2012

유수의 침식과 퇴적작용은 지형의 변화를 일으키며, 이런 지형변화는 하천 흐름, 지하수 흐름 등의 변화를 가져오며 이는 다시 지형변화의 원인이 된다. 이런 일련의 과정이 되풀이되는 것을 지형발달이라 하며, 이는 수문 현상에도 지대한 영향을 미친다. 지형발달의 주요 인자에는 강우와 지반 융기 등이 있으며 각 주요 인자들은 복합적으로 지형발달에 영향을 준다. 하지만 지형발달 탐구 시 실제 지형을 대상으로 탐구하기에는 한계가 분명히 있다. 그래서 본 연구에서는 컴퓨터를 이용해 수식을 계산하여 수치적으로 지형발달을 모의하는 모형을 이용하여, 지형발달에 영향을 주는 강우와 지반 융기를 중점적으로 탐구하였다. 지형발달모형을 이용하면 더욱 다양한 관점에서 지형발달과정의 역동성을 파악하는 새로운 시도들이 가능하다. 특히 특정 환경 조건에서의 논리적인 지형의 반응을 통한 해석이 가능해져, 환경 변화로 어떠한 지형변화 또는 지표물질 수지 변화가 있을지를 예측할 수 있다(변종민, 2011). 또한, 지형발달 일련의 과정들을 살펴볼 수 있기 때문에 시 공간적 제약에서 벗어날 수 있다. 그러므로 지형발달모형은 강우와 융기 조건에 따른 지형발달을 모의하기에 적합하다. 본 연구는 LEGS을 이용하여 강우와 융기 조건에 따른 지형발달 모의를 진행하였다. LEGS는 지표수의 흐름을 탐색하는 방법으로 GD8을 이용한 물리 기반의 수치적 지형발달모형이다(Paik, 2012). 본 연구에서는 강우의 변동과 융기 조건의 변화가 지형발달에 상당한 영향을 미치는 것을 발견하였다. 특히, 유역의 표고차이 등과 같은 정량적인 지표의 변화에 주목하여 각종 분석을 하고, 물리적 원인을 고찰하였다.

• The korean journal of orthodontics
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• v.40 no.6
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• pp.411-420
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• 2010

Objective: The purpose of this study was to assess the changes in height and inclination of the articular eminence during the growth period. Methods: One hundred and sixty subjects (71 males and 89 females) with a normal skeletal pattern and TMJ function, ranging in age from 5.9 to 19.7 years were divided according to their chronological age into six groups. Lateral individualized corrected TMJ tomograms were taken of all subjects, and the height and inclination of the articular eminence were measured. UNIANOVA was used to compare the differences between the age groups. Mann-Whitney test was used to compare the differences between male and female subjects. Results: The height and the inclination of the articular eminence were increased and became steeper with age, and the height and the inclination were larger in male than in female subjects. Conclusions: Dynamic changes in the height and the inclination of the articular eminence were observed during the growth period, therefore a full understanding of the growth of the articular eminence is important for orthodontic and orthopedic treatment in this period.

• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.75-84
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• 2020

This paper described the analysis result on heaving of soft ground with DCM column type, based on the results of laboratory model tests on the soft ground with DCM column. The heave characteristics of the soft ground were evaluated according to the application of DCM column in soft ground. The results showed that the heaving of soft ground without DCM column occurred rapidly when the lateral deformation of soft ground increased significantly under the 4th load step condition. In addition, the heaving of soft ground in final load step caused tensile failure of the ground surface. The maximum heaving of the soft ground with the DCM column occurred in the final load step, and the heaving quantity decreased in the order of pile, wall, and grid type. Especially, the soft ground with DCM of grid type effectively resisted ground heaving, even if it was extremely failure in the bottom ground of embankment. The results of the maximum heaving according to the measurement point showed that the heaving of the soft ground with DCM of grid type was 3.1% and 1.6% compared to that of the pile and wall type at the location of LVDT-1, and the heaving of the LVDT-2 position was 1.0% and 2.1%, respectively.

• 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 GEO-environmental Society
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• v.24 no.2
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• pp.5-12
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• 2023

In this study, the amount of heaving soil and the heave characteristics of the heaving soil generated at the actual site were quantitatively analyzed through DCM laboratory test construction. By reproducing a series of construction processes of the DCM method in a large-scale soil tank close to the actual site, the amount of heaving soil was predicted and the elevation characteristics such as elevation, diffusion range, diffusion angle and amount of elevation of the heaving soil were evaluated. As a result of the laboratory test construction, the actual elevation in terms of similarity within the DCM improvement section is 0~8.18m, and an average of 3.50m is observed. The actual diffusion range of the heaving soil converted to the similarity ratio is distributed from 28.0 to 38.0m on the left and right sides of the improvement section. The total amount of heaving soil calculated by the SUFFER program based on the results of the laboratory test construction is 19,901m³. Compared with the injected slurry amount of 16,992m³, the amount of heave compared to the injected amount is analyzed as 85.4%. The diffusion angle of DCM heaving soil, which analyzed the results of DCM laboratory test construction with the SUFFER program, is measured to be 30.0~38.0° at a depth of 50.0m, and is evaluated as an average of 34.0°. On the other hand, based on the DCM laboratory test construction and the analysis results using the program performed in this study, the amount of heaving soil at the DCM depths of 40.0m and 60.0m is predicted.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.6
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• pp.675-683
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• 2001

In this paper, we propose the edge compensation algorithm which connects the adjacent edges without losing the information of the skeletons on the edge image. The proposed edge compensation algorithm is composed of succeeding two steps. In the first step, the uplifted image is obtained by uplifting the edge image repeatedly. The next step is to extract the edge image from the uplifted image using the skeleton extraction algorithm. Experimental results show that the proposed method connects the adjacent edges without the distortion of the original edge information compared to the traditional method.

• Journal of the Korean Geotechnical Society
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• v.39 no.11
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• pp.33-40
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• 2023

This study explores the performance of pile foundations in highly expansive soil, incorporating magnesium oxide-based refractory materials. A controlled model chamber, housing a fixed pile, was utilized to induce ground expansion through fused magnesia (FM). The investigation focused on measuring the vertical displacement of FM-sand mixtures and the axial load on the pile in relation to depth and time. The study varied the amount of FM content (FM_c) at 30%, 50%, and 70%. The upward movement exhibited an augmentation with increasing FM_c, tapering off with depth as accumulation progressed toward the mixture surface. Compression and tensile forces were both evident along the pile for FM_c at 30% and 50%, while only a tensile force was observed at an FM_c of 70%. These results offer valuable insights for the analysis of pile behavior within FM-sand mixtures.