• 한국물환경학회지
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• 제36권1호
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• pp.29-35
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• 2020

To manage the non-point source pollution and restore the water circulation, many technologies including infiltration or reservoir systems were installed in the urban area. These facilities have many problems regarding maintenance as their operation period becomes lengthier. The purpose of this study was to estimate the optimal maintenance timing through a long-term load test on the infiltration trench as one of the low impact development techniques. An infiltration trench was installed in the demonstration test facility, and stormwater was manufactured by Manual on installation and operation of non-point pollution management facilities from the Ministry of Environment, Korea and entered into the infiltration trench. Particle size distribution (PSD), suspended solids (SS) removal efficiency, and infiltration rate change tests were performed on inflow and outflow water. In case of the PSD, the maximum particulate size in the outflow decreased from 64 ㎛ to 33 ㎛ as the operating duration elapsed. The SS removal efficiency improved from 97 % to 99 %. The infiltration rate changed from 0.113 L/sec to 0.015 L/sec during the operation duration. The maintenance timing was determined based on the stormwater runoff requirements with these changes in water quality and infiltration rate. The methodologies in this study could be used to estimate the timing of maintenance of other low impact development techniques.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.649-654
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• 2005

Shallow slope failures in residual soil during periods of prolonged infiltration are common over the world. One of the key factors that dominate slope stability is hydrological response associated with infiltration. Hence, the soil-water profile during rainfall infiltration into unsaturated soil must me examined to evaluate slope stability. However, the hydraulic response of unsaturated soil is complicated by inherent uncertainties of the soil hydraulic properties. This study presents a methodology for assessing the effects of parameter uncertainty of hydraulic properties on the response of a analytical infiltration model using first-order reliability method. The unsaturated soil properties are considered as uncertain variables with means, standard deviations, and marginal probability distributions. Sensitivities of the probabilistic outcome to the basic uncertainties in the input random variables are provided through importance factors.

• 융합보안논문지
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• 제5권4호
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• pp.1-6
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• 2005

네트워크 시스템에 대한 악의적인 접근과 정보위협이 증가하고, 그 피해또한 기업에서 개인 사용자까지 확대되고 있다. 침입탐지 시스템, 침입차단 시스템 등 단위 보안 기능만을 제공하는 제품은 분산화, 지능화 되어가고 있는 복합적인 침입에 대한 대응에 한계가 있다. 여러 보안 제품을 연동하여 해커의 침입탐지, 대응 및 역 추적을 위한 통합 보안 관리의 필요성이 대두되고 있다. 그러나 통합보안 관리의 특성상 다양한 보안 제품에서 전송된 이벤트와 침입경보의 양이 많아 분석이 어려워 서버측의 부담이 되고 있다. 따라서 본 논문에서는 이러한 문제점을 해결하고자 침입경보 데이터를 축약하는 방법에 대하여 연구하고자 한다.

• 한국세라믹학회지
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• 제32권6호
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• pp.710-718
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• 1995

The new forming method, Pressureless Powder Packing Forming Method was applied to the manufacturing of reaction sintered SiC. After the experiments of vibratory powder packing and binder infiltration, the abrasive SiC powder of which mean size is 45${\mu}{\textrm}{m}$ was selected to this forming method. Uniform green bodies with porosity of 45% and narrow pore size distribution could be formed by this new forming method. Also, complex or varied cross-sectional shapes could be easily manufactured through the silicone rubber mould used in this forming method. Maximum 15 wt% amorphous carbon was penetrated into green body by multi impregnation-carbonization cycles. And reaction-bonded SiC was manufactured by infiltration of SiC-carbon shaped bodies with liquid silicon.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.229-230
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• 2011

We could see that, the thinner the retaining wall is, the more advantageous Premixed Agent Type Waterproof method is in the aspect of economic efficiency. The reason is because, in the case of Premixed Agent Type Waterproof method, the thicker the retaining wall is, the higher the construction cost increases due to increase in the material quantity required which increases in proportion to the area in the case of Premixed Agent Type Waterproof method. We could see that, the thinner the retaining wall is, the more inferior the economic efficiency of Infiltration Type Waterproof method is to that of Premixed Agent Type Waterproof method, as, in the case of Infiltration Type Waterproof method, the quantity of material required is fixed in proportion to the area. Consequently, we concluded that Premixed Agent Type Waterproof method is economically advantageous up to the wall thickness of 700 mm and Infiltration Type Waterproof from 800 mm.

• 한국주조공학회지
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• 제16권6호
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• pp.523-536
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• 1996

This paper relates to fabrication processing analysis of metal matrix composites by the injection of liquid metal into a fibrous preforms. One dimensional heat transfer analysis during squeeze infiltration process of aluminum base composites has been studied. An analysis method was investigated for the temperature distribution, infiltration velocity and melt infiltration characteristics with the commercial preform with short fiber array. When molten metal is infiltrated in a fibrous preform with random orientation, phase transformation will be occurred in a region such as molten metal, solidified region, preform region and infiltration composites region. a mathematical modelling for a solidification phenomena in fabrication process of metal matrix composites using a squeeze infiltration technique was investigated by the basic relations for liquid metal into a fibrous preform. The temperature distribution of theoretical results was compared with experimental data.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.192-199
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• 2010

This research produced internal model tester ($2.0m{\times}2.0m{\times}1.0m$) to evaluate the field application of Paju Unjeong District water recycling system for small streams eco-friendly river bed disparity method for the first time in Korea and conducted comparative analysis of the Paju Unjeong District water recycling system field test results and infiltration rate result of internal tests by each rainfall intensity following surface material. Infiltration rate result of internal tests concrete pavement by rainfall intensity following surface material, asphalt pavement, bentonite mate, stabilized soil construction and mixed soil construction manifested low infiltration rate. On the contrary, compaction soil, grassland and water permeable packaging materials resulted in significant amount of infiltration rate. As for the field permeability test results, they were manifested similar tendency as indoor permeability test results and they satisfied the standard for standard of water permeability of domestic disparity facility (less than $1.0{\times}10-7cm$/sec). As compaction rate increased, unconfined compression strength increased as well while coefficient of water permeability decreased.

• 한국멀티미디어학회논문지
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• 제20권3호
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• pp.482-490
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• 2017

Early detection of infiltration is one of the most important tasks of nurses to minimize skin damage due to infiltration. For subjects receiving invasive intravenous treatment, the bioelectrical impedance (impedance) were measured in the frequency range of 5 to 500 kHz using bioelectrical impedance spectroscopy (BIS). After attaching electrodes at both ends of a transparent dressing mounted on the skin in which IV solution was infused into the vein, the change in impedance was measured as a function of time and frequency before and after infiltration. The experimental results are described as follows. When IV solution was properly infused into the vein, the impedance was nearly constant over time and decreased with increasing frequency. However, when infiltration occurred, the impedance decreased significantly and thereafter gradually decreased with time. In addition, impedance decreased with time for all applied frequencies. In this study, when IV solution penetrated into the surrounding skin and subcutaneous tissue by infiltration, impedance was quantitatively analyzed for as a function of time and frequency. This suggests a method for early detection of infiltration using BIS.

• 상하수도학회지
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• 제24권6호
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• pp.691-701
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• 2010

As the water-cycle is transformed by increasing of the impermeable area in process of urbanization, decentralized rainwater management facilities(infiltration, harvesting and retention facilities) as source control are considered to be a method of restoring water-cycle of urban and reducing runoff. SWMM model was used to analyse the change of water-cycle structure before and after development in A new town watershed. Modified SWMM code was developed to apply infiltration facilities. The modified SWMM was used to analyse the change of water-cycle before and after infiltration trench setup in AJ subcatchment. Changes of the impervious area by development and consequent increase in runoff were analyzed. These analyses were performed by a day rainfall during ten years from 1998 to 2007. According to the results, surface runoff increased from 51.85% to 65.25 %, and total infiltration volume decreased from 34.15 % to 21.08 % in A newtown watershed. If more than 80 infiltration trenches are constructed in AJ subcatchment, the low flow and the drought flow increases by around 47%, 44%, separately. The results of this study, infiltration trench is interpreted to be an effective infiltration facility to restore water-cycle in new town.

• 대한토목학회논문집
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• 제36권6호
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• pp.1133-1143
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• 2016

본 연구는 하수관거정비 임대형민자사업에 있어 사업효과 분석지표의 개선에 대한 연구이다. 하수관거정비 임대형민자사업의 평가지표 중 침입수에 대한 평가지표는 단일평가항목으로 17.5점의 높은 점수가 부여되고 있다. 침입수에 대한 평가지표는 침입수의 발생량에 초점을 맞추어 평가되고 있으며, 현재 '야간 생활하수 평가법'에 따라 계산되고 있다. 그러나, 본 평가지표가 제주지역의 지질적 특성을 반영하지 못하고 있다는 것이 운영단계에서 문제점으로 대두되고 있다. 따라서 본 연구에서는 제주지역을 중심으로 평가지표에 따른 계산 결과와 실제 침입수의 발생량을 비교 분석하고자 하였다. 이를 위해서 제주도내 5개 지역에 대하여 '야간 생활하수 평가법'에 따른 침입수 발생량을 분석하였다. 또한 실제적으로 침입수가 발생하는 조건에 대하여 전수조사를 실시하였다. 분석 결과, 지하수위가 하수관거보다 밑에 분포되고 있으며, 하수관거의 기능에 대한 검증 결과 하수관거의 결함 등에 의한 침입수 발생은 없는 것으로 분석되었다. 따라서 현재 평가지표로 활용되고 있는 '야간 생활하수 평가법'은 제주지역에 적용하기에 적합하지 않다는 결론에 도달하게 되었으며, 제주지역만의 침입수 관련 기준 마련이 필요할 것으로 사료된다.