• Analytical Science and Technology
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• v.16 no.3
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• pp.212-217
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• 2003

The memory effect of silver and aqua regia in the vessel by their permeation was studied during the microwave digestion of samples under the operating conditions of high temperature and pressure. The extent of permeation in vessels with the solution containing silver 5 mg has been shown to be $0.97{\mu}g/mL$ for the digestion of $HNO_3$ solution and $0.47{\mu}g/mL$ for the digestion of oil sample under condition of MDS 180T program ($180^{\circ}C$, 220 psi).

• The Journal of Engineering Geology
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• v.28 no.2
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• pp.277-295
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• 2018

As it has become difficult to secure new water resources through dam construction due to the critical social public opinions on dam construction from 10 years ago, it is necessary to review the existing water resources through the review of existing dams. Accordingly, access methods, such as planning, construction and management, were carried out using technologies already accumulated in relation to the repair and reinforcement of the dam. As a result of the repair and reinforcement, permeation grouting has been performed in many dams, but the establishment of the technology is insufficient so far, and the published paper at home and abroad is extremely rare. In this thesis, low-pressure penetration and grouting reinforcement technologies for the YC dam are analyzed in detail. As a result, penetration grouting has shown that it can be effectively applied to the improvement in the constallability of the core fill-like a YC dam. In addition, the technical details of the experience-proven penetration grouting are given in relation to the injection criteria. It is deemed that the specific analysis data of the Fill Dam penetration grouting technology through this study can be used as useful data for strengthening the repair of Fill Dam and reservoir.

• Journal of the Society of Disaster Information
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• v.11 no.3
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• pp.318-328
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• 2015

Effective urban flood reduction and restoration of natural water cycle at present include the application of permeable pavements. The application of permeable pavement addresses urban water cycle and disaster related events which gained attention internationally. However, few researches have been conducted to investigate unsaturated behavior and evaluate the water characteristics curves of these type of pavement materials most especially in the unsaturated state. In this study, first the saturated permeability and the soil-water characteristics curve of a pervious concrete are evaluated based on laboratory tests, and, based on experimental results, the infiltration of permeable pavement system is numerically modelled. In the soil-water characteristics curve of a pervious concrete, the volumetric water content drops very steeply after the air entry value with increasing matric suction. From the finite element analyses, the performance of the permeable pavement when compared to impermeable pavement, confirmed that the whole system effectively delayed and reduced runoff.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.315-315
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• 2021

저영향개발은 녹색 기반시설을 이용한 침투, 여과, 저류, 지체 등의 효과를 달성하는 구조적 방식과 집중된 우수 배제 방식을 분산시키는 비구조적 방식이 있다. 국내에서는 저영향개발을 주로 시범사업 수준에서 침투트렌치, 식생수로, 투수성 포장과 같은 일부의 요소기술만 적용하고 있는 실정으로, 비구조적 방법을 이용한 분산식 우수배제 방식을 도입한 사례는 거의 없다. 본 연구에서는 PCSWMM을 이용하여 송산 그린시티 개발 사업에 기존의 집중형 우수 배제 방식과 비구조적 방식을 포함한 저영향개발을 각각 도입하여 홍수 및 침수 저감 효과를 검토하였다. 본 연구에서는 송산 그린시티에 저영향개발 기법을 고려하면서 기존 4개의 주 수로에 2개의 소규모 수로를 추가적으로 고려하였다. 또한, 우수관거는 연장이 길어짐에 따라 관거의 규모가 커지므로 유역 유출부에 인접한 지역은 직접 우수 배제가 되도록 하였고, 우수의 배제 방향을 분산시킴으로써 관거의 규모가 비대해지지 않도록 하였다. 홍수 및 침수 저감 효과는 50년 빈도 확률 강우량과 100년 빈도 확률강우량을 적용하여 검토하였다. 그 결과, 적용된 집중형 우수 배제 방식의 경우에는 50년 빈도 확률강우량 조건에서 48 ha, 100년 빈도 확률강우량에서는 81 ha가 침수되는 것으로 모의가 되었다. 반면, 분산형 우수배제 방식을 포함한 저영향개발을 반영할 경우, 50년 빈도 확률강우량에서 6 ha, 100년 빈도 확률강우량 조건에서는 18 ha가 침수되는 것으로 모의가 되었다. 즉, 분산형 빗물관리를 계획함에 따라 홍수 저감의 효과가 나타나는 것으로 분석되었다.

• 한국방재학회:학술대회논문집
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• 2010.02a
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• pp.47.2-47.2
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• 2010

빗물을 노상 침투시키는 투수성포장은 물순환 보전과 차량 주행 안전성 확보와 같은 효과를 기대할 수 있다. 지금까지 보도나 주차장 같이 비교적 교통조건이 열악하지 않은 구간에 적용되고 있지만 우수 침투로 인해 노상이 연약화 될 것을 우려하여 현재까지 차도에 적용하지 못하고 있으며 설계 방법 또한 정립되어 있지 못한 실정이다. 본 연구에서는 투수성포장의 포장단면을 설계하기 위한 방안으로 단지내 포장을 투수성포장으로 설계할 경 물의 침투로 인해 노상의 지지력이 약화 된다고 가정하고 노상 지지력의 약화에 따른 포장층의 역학적 거동 특성을 유한요소 해석을 통하여 분석하여 구조적 안정성을 확보할 수 있는 포장두께를 분석하였다. 또한 설계 개념에서 노상의 지지력 저하에 따른 포장두께의 할증방안과 할증두께를 분석하였다.

• Water for future
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• v.9 no.1
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• pp.55-69
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• 1976

The purpose of this paper is to provide basic data for construction methods of leakage pretaction for estuary barrien which is constructed to in take restoration water from irigative use and a river flow in its ultimate dsicharge to ward to sea, The water, accordingly, has reviewed the discrepancis between theories and experiments based on the hydraulic analysis of ground water through a series of sourveys on equi-patential line of seepage flow and a series of some experiments. apparently, however, the research results herein might reflect in some part not more than inference since those experiments are not conducted in a real foundation but from an indoor experiment or calculation, conclusion in brief are itemized here-under. 1. small-scale barrier require cut-off wall, which should reach the complete impereable layer, 2. Duplication barrier is provided effective in protection saline water seepage. 3. a barrier with broad crest might enable protection of massive seepage by fresh water lens formed from precipitation.

• Journal of the Korea Society for Simulation
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• v.22 no.2
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• pp.33-40
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• 2013

This paper explores a border security system based on agent-based modeling and simulation (ABMS). The ABMS software platform, map aware non-uniform automata, is used to model various scenarios and evaluate the border security system given a set of infiltrators who have evolutionary behavior governed by genetic algorithm (GA). we formulated an optimization model and approximately solved it using a GA in order to capture near optimal behavior of an infiltrating force. The results presented give two significant insights for our border security system in that optimizing the infiltrator's behavior can make a significant difference and the quantitative results regarding the infiltrator's avoidance of each asset can be viewed as capturing their relative importance.

• Journal of the Korean Geosynthetics Society
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• v.15 no.3
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• pp.39-47
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• 2016

In order to prevent leakage of leachate in offshore landfill, hydraulic barrier is indispensable. In the case of rubble mound revetment at offshore landfill, HDPE sheet in slope should be installed. In this study, seepage analysis were performed to evaluate seepage and flow in the seabed and revetment according to extended length of HDPE sheet by using SEEP/W. Results show that, in the case of low permeability layer is distributed where extended length of HDPE sheet was more than 1m, seepage flux in seabed and revetment was greatly reduced. In order to prevent seepage in seabed and revetment in the case of sand layer of high permeability is existed above low permeable layer, extended length of HDPE sheet and impermeable improvement width of permeable layer should be more than 1m at seabed.

• Journal of the Korean Geotechnical Society
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• v.30 no.10
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• pp.5-18
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• 2014

Many regions around the world are vulnerable to rainfall-induced slope failures. A variety of methods have been proposed for revealing the mechanism of slope failure initiation. Current analysis methods, however, do not consider the effects of non-homogeneous soil profiles and variable hydraulic responses on rainfall-induced slope failures. In this study, probabilistic stability analyses were conducted for weathered residual soil slopes with different soil thickness overlying impermeable bedrock to study the rainfall-induced failure mechanisms depending on the soil thickness. A series of seepage and stability analyses of an infinite slope based on one-dimensional random fields were performed to consider the effects of uncertainty due to the spatial heterogeneity of hydraulic conductivity on the failure of unsaturated slopes due to rainfall infiltration. The results showed that a probabilistic framework can be used to efficiently consider various failure patterns caused by spatial variability of hydraulic conductivity in rainfall infiltration assessment for a infinite slope.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.264-272
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• 2007

Runoff of non-point pollutants has affected bad influence to water quality of river as reaching within short time. For this reason, reducing them prior to reaching aquatic systems or treating them after collection from discharge process of pollutants are desirable for efficient treatment of pollutants. This study was carried out to develop an ecotechnological method to prevent further aggravation of water quality by non-point source through vegetation filter strips. This study has placed a focus on improving infiltration capacity of soil for the optimum condition of vegetation filter strips. Therefore, we used titled soil filter strips instead of vegetation filter strips in this study. The three types of soil tilter strips were used in a bench scale experiment before applying to the field. The reduction efficiency of pollutants in soil filter strips (SS $84.5{\sim}92.5%$, BOD $67.9{\sim}80.6%$, T-N $43.4{\sim}76.6%$, T-P $40.6{\sim}87.4%$, Cu $28.3{\sim}48.1%$ Fe $92.1{\sim}97.7%$, Pb $81.4{\sim}97.3%$) was much higher than that of the controled group. And non-point pollutants reduction efficiency by soil filter strip's forms was estimated to be distinguishing in order of bio material, mixture of sand and gravel and lastly the whole gravel. In the event, the whole reduction efficiency of pollutants on the soil filter strips disclosed good results.