• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1857-1861
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• 2010

이 연구는 하천 제방의 누수 문제에 대해서, 누수의 실태, 대책공 및 조사 방법에 관한 사례를 수집 정리하는 동시에, 이들 사례에 기반한 누수 특성, 하천 특성에 따른 대책공 및 조사 방법에 대해서 검토하기 위한 목적으로 수행하였다. 제방 누수는 일반적으로는 하천수가 제체 또는 기초 지반에 침투해서 제방의 제내 비탈면, 제내 비탈끝 또는 제내지에서 스며나오는 현상을 총칭하며, 각 누수 형태의 개념과 특징을 정리하였다. 1987년 일본의 건설성 하천국의 토목연구소에서 수행한 약 300건의 누수사례에 관한 검토보고서를 참고하여 일본의 하천 제방의 누수 특징을 요약 정리하였다. 제방의 침투/누수 대책 공법을 4가지로 분류하여 특징을 정리하였다. 하천 제방의 제체 누수에 대한 제방 강화 대책 공법의 선정 과정 및 지침을 제시하고자 한다.

• Journal of the Korean GEO-environmental Society
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• v.17 no.7
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• pp.5-13
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• 2016

This research is focused on the seepage behavior of embankment which had the weak zone with big permeability. The distributed TDR (Time Domain Reflectometer) and point sensors such as settlement gauge, pore water pressuremeter, vertical total stressmeter, and FDR (Frequency Domain Reflectometer) sensor were used to measure the seepage characteristics and embankment behavior. Also, the measured data were compared to the data of 2-D and 3-D numerical analysis. The dimension of model embankment was 7 m length, 5 m width and 1.5 m height, which is composed of fine-grained sands and the water level of embankment was 1.3 m height. The seepage behavior of measuring and numerical analysis were very similar, it means that the proper sensing system can monitor the real-time safety of embankment. The result by 2-D and 3-D numerical analysis showed similar saturation processing, however in case of weak zone, the phreatic lines of 2-D showed faster movement than that of 3-D analysis, and finally they converged.

• Journal of the Korean Geosynthetics Society
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• v.9 no.3
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• pp.77-85
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• 2010

The change of water level in reservoirs is an important factor causing failure of bank slopes, i.e. landslide. The water level of Three Gorges reservoir in China fluctuate between 145 m and 175 m, as a matter of flood control. During its normal operational state, the rate of water level fluctuation is supposed to range from 0.67 m/d to 3.0 m/d. Majiagou slope is located on the left bank of Zhaxi River, 2.1 km up from the outlet. Zhaxi River is a tributary of the Yangtze River within the Three Gorges area, of which the water level changes with the reservoir. At the back of Majiagou slope, a 20 m long and 3~10 cm wide fissure developed just after the reservoir water level rose from 95 m to 135 m in 2003. This big fissure was a full suggestion of potential failure of this slope. In this study, unsaturated-saturated seepage analyses were carried out to simulate the change of pore-water pressures in the bank slope subjected to the reservoir water level change. The obtained pore-water pressures were then used to evaluate the change in factor of safety (FS) with reservoir water level. It was found that the phreatic line showed a delayed response with respect to the change of the reservoir water level, because the seepage through soil layer was generally slower than water flows itself. During the rising and drawdown process, the phreatic lines take the shapes of concave and convex, respectively. And the fluctuation of reservoir water level just affected the front part of the bank slope, but had little influence on the back of the slope.

• Journal of the Korean Geotechnical Society
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• v.21 no.8
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• pp.63-72
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• 2005

Rocks are dumped to soft marine ground in order to improve trafficability and construction conditions in the tideland reclamation construction sites. Though this rock layer under earth fill has caused in a serious seepage problems after construction, seepage behaviors of this embankment structure is not correctly investigated. Water flow through rock layers is, in general, known as Non-Darcy's flow. However, the embedded rock layer under earth fill is not known whether its flow is governed by Darcy's or Non-Darcy's law. Therefore, a numerical analysis, laboratory model test and filed investigations were performed for analyzing the those seepage characteristics in this research. Results show that there is significance of $95\%$ of confidence between observed heads and seepage rates, and the calculated ones by SAMTLE which is developed under the assumption that the water flows through the two-layer system obey the Darcy's flow. And after operating the hydraulic gradient(i) of $0.10\~0.55$ upon laboratory model, these seepage characteristics of the embedded rock layer show that Reynolds Numbers are less than 10 and the relationship between these velocities of rock layer(v) and hydraulic gradients(i) is linearly proportional with more than 0.79 of the coefficient of correlation $(R^2)$. And the Reynolds Number of the velocity calculated by the relation of v=ki in the embedded rock layer of OO sea dike is $1\~6$. It shows also laminar flow. Based on these results, it is concluded that the seepage characteristics of embedded rock layer under earth fill can be laminar and Darcy's flow.

• Journal of the Korean Geotechnical Society
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• v.36 no.6
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• pp.5-15
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• 2020

This study deals with the use of porewater pressure transducers to evaluate the stability of a fill dam through the correlation between the porewater pressure and water level. As a result of performing principal component analysis on a total of eight porewater pressure transducers installed in the fill dam, they were distributed into three groups. It was found to be distributed as internal, external, and top based on seepage line in the dam body. The correlation coefficient between porewater pressures and water level in group A located inside the seepage line indicated 0.94 to 1.00 and they are showing a strong positive linear relationships. It indicates that maintenance of the dam is required by the porewater pressure transducers of the group A. In addition, a linear regression analysis was performed with the determination coefficients of the group A of 0.89 to 0.99. It was found that the pore water pressure can be predicted and the stability of the dam can be evaluated by comparing it with the currently measured values when the water level is fixed as an explanatory variable.

• Food Science and Preservation
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• v.22 no.1
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• pp.19-26
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• 2015

Indole 3-carbinol (I3C), important component of cruciferous vegetables and its major acid-catalyzed metabolite, 3,3'-diindolylmethane (DIM) have been suggested to have an inhibitory effect on the tumor growth and metastasis. This study investigated the effect of DIM on the adhesion, migration and invasion of highly invasive PC3 and DU145 human prostate cancer cell lines. Cells were grown in Dulbecco's modified Eagle's medium (DMEM) supplemented with 3.0 g/L glucose, 3.7 g/L sodium bicarbonate and 10% fetal bovine and were incubated in a humidified incubator at $37^{\circ}C$ and 5% $CO_2$. DIM reduced the adhesion of PC3 and DU145 cells in a dose dependent manner. The pretreatment of PC3 cells with DIM reduced the adhesion dose dependantly, but inhibition was less effective than the treatment with DIM during the adhesion assay. The migration and invasion of PC3 and DU145 cells were reduced by DIM dose dependantly, and the inhibition of DIM was less effective in the DU145 cells than in the PC3 cells. The pretreatment of PC3 cells with DIM for 24 hr before the assay reduced invasion of PC3 cells by 37%. These results suggest that DIM inhibits adhesion, migration and invasion of the PC3 and DU145 cells and may be an effective antimetastatic therapy in addition to traditional chemotherapy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.4
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• pp.15-22
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• 1985

The author has studied the collapse of a slope with seepage occuring in sand model with a trapezodial cross section. The primary objective of this study was to examine the failure phenomenon of embankment with respect to change in void pressure at embankment slope. The contents of this experiments are as follows; 1) Determination of exit point by seepage line. 2) Evaluation of partial failure at exit point. 3) The effects of seepage force at embankment.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1395-1399
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• 2008

국내 토층 사면을 대상으로 강우에 의해 발생되는 침투수 거동 특성을 분석함으로써 지속적인 토층의 물성 변화 계측을 통해 산사태 예 경보시스템을 구축이 가능하다. 본 연구에서는 산사태 예 경보시스템 구축의 사전 단계로써, 국내 대표적인 지질 매질인 화강암 풍화토, 편마암 풍화토와 주문진 표준사에 대해 공극률과 체적함수비 등의 토질 물성 변화를 고려한 실내 보정실험을 수행하였다. 실험조건은 공극률, 체적함수비 변화에 대한 측정센서의 측정 정밀도 향상과 이를 통해 국내 현장토에 대한 고유 보정기법을 제시하기 위함이다. 측정센서는 각 실험 조건별 물성 변화에 따라 전압을 측정함으로써 현장토에 대한 물성치와 상호 분석이 가능하도록 하였다. 주문진 표준사 뿐만 아니라 국내 현장토인 화강암 풍화토와 편마암 풍화토에 대한 체적함수비에 대한 보정식도 함께 제시하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1878-1882
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• 2010

이 연구는 제방의 침투 수리모형 실험의 자료를 이용해 안전도 평가 지표 선정을 위한 자료 제공하고 향후 수행할 침투 수치모의에 필요한 보정 및 검증 자료를 확보할 목적으로 수행하였다. 제방 축조 현장에서 구한 제체재료를 사용하여 실험실에 제방축소모형을 $14.5m{\times}0.6m{\times}1.6 m$의 수조 내부에 제작하였다. 제방 사면의 경사는 1:2, 제방 저면의 길이는 4.60 m, 제방 상부의 길이는 2.40 m, 제체의 높이는 0.55 m로 제작하였다. 모형제방은 제방축조 방법과 유사하게 다짐을 하기위해 흙을 쌓으면서 0.20 m 높이 마다 다짐을 실시하였다. 다짐방법은 고무망치를 이용한 층다짐을 하였다. 들밀도실험에 의한 제방모형의 건조단위중량과 다짐도는 각각 1.71g/cm3, 93%로 측정되었다. 홍수위 증가에 따른 비정상 상태의 침투수위 측정을 수행하였다. 수리모형실험은 약 8일 동안 수행하였다. 침윤선의 수두와 위압계별 수두는 상류쪽(제외지 사면)부터 증가하기 시작하며 하류쪽(제내지 사면)로 확장됨을 알 수 있으며, 실험 초기에는 상류쪽의 수두가 급격히 상승하지만, 점차 상승속도가 둔화되는 등의 일반적인 경향이 나타나고 있음을 확인할 수 있다. 실험시작 18시간 경과 후부터 제외지 사면 하단부에서 유출이 발생하였으며, 21시간 경과 후부터는 상류부의 수두가 안정되는 현상이 나타났다. 측정된 침투수위의 변화 양상은 향후 수치모형을 이용한 침투해석의 검보정 자료로 활용할 계획이다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.654-658
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• 2012

국내에서 수행한 대부분의 제방 침투에 대한 수리모형실험 연구는 제체만을 대상으로 수행되었으며, 투수성 기초지반을 고려한 연구는 찾아보기 어려운 상황이다. 이 연구에서는 개정된 제방설계기준에 따른 1:3의 비탈경사와 투수성 기초지반을 가지는 제방의 침투실험을 수행하였으며, 향후 제방침투 수치모의에 필요한 검보정 자료를 확보할 목적으로 수행하였다. 부산광역시 강서구에 위치한 낙동강 제2하구둑 건설 현장에서 제체의 재료를 채취여 입도분석과 들밀도시험을 통해 제방의 건조단위중량과 다짐도 및 제방의 투수계수는 각각 $1.372g/cm^3$, 93%, 1.35 m/day이며 통일분류법의 SM에 속하는 것으로 확인하였다. 0.45 m, 0.50 m, 0.55 m, 0.60 m의 4가지 수위(각각 Case-1~4) 조건에 대하여 정상상태에 도달할 때까지 실험을 계속한 결과 각각의 실험조건별 침윤선은 대체로 동일한 양상을 보였지만 몇 지점에서 위압수두계 수위의 이상점이 발견되었다. 제방을 해체하면서 원인을 찾아본 결과 머드볼이 형성되어 있음을 확인하였으며, 침투 흐름에 상당한 영향을 미쳤을 것으로 생각된다.