• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.969-978
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• 2010

In this study, a laboratory model test on utilization of recycled aggregates and crushed stone as vertical drains to use alternative material of sand in soft ground is performed. The vertical and horizontal coefficient of permeability of the recycled aggregates and crushed stone showed largely 1.2~4.0 times and 3.0~3.3 times greater than sand, respectively. Therefore, it showed enough to be an alternative material to the sand which had been being used as the vertical and horizontal drainage material before. The variations of pore water pressure with time showed constantly regardless of the load in all vertical drainage materials. When water level drops suddenly, the pore water pressure of the recycled aggregate and crushed aggregate is reduced to nearly zero. Therefore, it was applicable to the field because discharge capacity was similarity to that of sand. The settlement in crushed aggregates and recycled aggregate decreases gradually with the load increase. When water level drops suddenly, earth pressure in all drains materials was evaluated the equivalent drainage capacity similarity to sand because it show approaching the nearly zero.

• Ocean and Polar Research
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• 제24권1호
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• pp.63-71
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• 2002

This preliminary study on the changes of macrobenthic assemblages in experimental sediment fences was conducted as a part of tidal marsh restoration project. Intertidal sediment fences were designed to increase the efficiency of trapping sediments on unvegetated tidal flats in order to raise sediment elevation and to allow colonization of intertidal vegetation. Although increment of soil surface level was not observed over the first three months of the study, it was possible to obtain some effects of the sediment fence. Three months later, the particle sizes of the surface sediment at experimental plots became much finer compared to unfenced areas on the natural mudflats located in the same tide level as that of the plots. The difference was much greater on the plot with drainage canals than on the plot without ones. Species diversity of the experimental plots became much higher than that of natural sites. Perinereis aibuhitensis and Glauconome chinensis which were absent from initial community appeared with high density in the plot with drainage canals. Those species were significantly different in abundance between the experimental plot and the natural mudflat. Changes in species composition were not detected in another experimental plot without drainage canals.

• 농업과학연구
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• 제37권1호
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• pp.97-104
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• 2010

In this study, a laboratory model test on utilization of recycled aggregates and crushed stone as vertical drains to use alternative material of sand in soft ground is performed. The vertical and horizontal coefficient of permeability of the recycled aggregates and crushed stone showed largely 1.2~4.0 times and 3.0~3.3 times greater than sand, respectively. Therefore, it showed enough to be an alternative material to the sand which had been being used as the vertical and horizontal drainage material before. The variations of pore water pressure with time showed constantly regardless of the load in all vertical drainage materials. When water level drops suddenly, the pore water pressure of the recycled aggregate and crushed aggregate is reduced to nearly zero. Therefore, it was applicable to the field because discharge capacity was similarity to that of sand. The settlement in crushed aggregates and recycled aggregate decreases gradually with the load increase. When water level drops suddenly, earth pressure in all drains materials was evaluated the equivalent drainage capacity similarity to sand because it show approaching the nearly zero.

• Journal of Chest Surgery
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• 제24권11호
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• pp.1154-1159
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• 1991

Anomalous systemic venous return to the right atrium is clinically innocuous and cause no functional disturbances or physiologic abnormalities by themselves and consequently require no treatment but may be surgical importance. We experienced a case of adult TOF combined with anomalous systemic venous drainage. Rudimentary right SVC with draining left sided vertical vein and IVC with separately drained left vein was revealed at operation time. With the bicaval cannulation, large sucker was used for drainage of blood from the left hepatic vein. Postoperative angiocardiogram showed above findings and combined double inferior vena cava at lumbar level.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.398-403
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• 2001

Since the urban subway is normally constructed under the groundwater level, the drainage system will be one of the most important factors during maintenance period. Therefore, to investigate suitability of the design approach and the construction specification, the inflow and the contents of the groundwater in the Route 5 of Seoul subway system are analysed. From these, the possibility of the design improvement and the economy of the maintenance cost are proposed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.766-771
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• 2003

In this study the drainage noises were investigated for the subjective allowing limitation and the testified classes. 7 point scale was selected to evaluate the annoyance level with vocabularies. As a result, 'a little annoying' is the most suitable expression for the allowing limitation, and the sound pressure levels for the urinal was 43.5㏈ and the bathtub was 44.6㏈.

• 대한토목학회논문집
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• 제36권3호
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• pp.395-406
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• 2016

도시화로 인한 인구집중 및 개발 집중현상으로 하천변 저지대 및 지하공간 사용이 증가하였고, 불투수층이 증가하여 도시유역의 배수체계는 우수관거에 의존하고 있다. 이러한 변화로 인한 우수관거의 저류용량 부족 및 외수위의 영향으로 인한 도심지 역류 현상으로 인한 침수피해가 발생하고 있다. 하지만 기존의 홍수범람에 관한 연구는 대부분 외수범람과 내수침수를 유기적으로 연결하지 못하고 있다. 본 연구에서는 상습침수가 발생하는 도시유역에 대하여 도시유역 유출특성을 고려한 홍수의 정확한 예측을 위해 강우분석 및 외수위를 고려하고, 도시유출모형인 SWMM 모형을 이용하여 하수관거의 월류를 분석하였고, 이 결과를 홍수범람해석 모형과 연계하여 도시유역에서의 집중호우 발생시 침수해석을 실시하여 수방시설물의 홍수배제 효율을 분석하였다. SWMM 모형의 적용결과 외수위영향에 따른 원활한 내수배제가 불가능 한 것으로 나타났고, 관거 월류량이 많아진 것으로 나타났다. 월류된 우수가 지면을 따라 흐를 경우 저지대의 침수가 예상되고, 월류량이 많은 맨홀을 주요맨홀로 선정하였고, 월류수 저감을 위한 방안으로 주요 맨홀의 인근 지역에 저류지를 설치하는 방안과 각 맨홀들을 연결하는 관거를 확대하는 방안을 설정하였다. 월류 저감 시나리오 적용 결과 저류지 설치시 월류량의 45%, 관거 확대시 33~64%의 저감효과를 보였다. SWMM 모형의 결과를 이용하여 홍수범람해석 모형을 모의한 결과 지표경사와 도로를 따라 맨홀 월류수가 모여 침수현상을 발생시키는 것으로 나타났으며, 관거 확대 적용시 침수면적이 19.6%, 60.5% 줄어든 것으로 나타났다.

• 한국잡초학회지
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• 제11권2호
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• pp.100-105
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• 1991

공시약제(供試藥劑) 모두가 천수조건하(淺水條件下)에서는 경미(輕微)한 정도(程度) 이상(以上)의 약해(藥害)가 있었으며, 특(特)히 bensulfuron-methyl은 3cm에서 그리고 pretilachlor는 1cm 천수(淺水)에서 약해(藥害)가 커졌으며 계량적(計量的)(초장(草長), 분벽수(分蘗數), 건물중(乾物重))으로는 처리후(處理後) 40일(日)까지도 생육억제(生育抑制)가 있었으나 달관적(達觀的)으로는 처리후(處理後) 15일(日) 경(傾)부터 빠른 회복을 나타내었다. 일당(日當) 감수심(減水深)이 증대(增大)됨으로써, 공시제초제(供試除草劑)의 전반적인 약해(藥害)가 증가(增加)되는 경향(傾向)이었으며, 특히 dimepiperate는 감수심(減水深)이 적은 곳에서의 초기생육(初期生育)에서만 다소의 생육지연(生育遲延)이 있었고 감수심(減水深)이 큰 사양토(砂壤土) 등지에서 사용(使用)이 제한(制限)되고 있는 bensulfuron-methyl은 어린묘(苗)의 경우, 감수심(減水深)과 관계없이 전반적(全般的)으로 높은 약해(藥害)를 나타내었다.

• 펄프종이기술
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• 제30권2호
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• pp.30-39
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• 1998

Effect of cationic starches and anionic colloidal silica on retention and drainage characteristics of Compozil system was investigated. Depending upon the degree of substitution and molecular weight of cationic starches and morphological characteristics of anionic colloidal silica, retention and drainage properties of Compozil system were significantly influenced. When cationic starch addition level increased above a certain limit retention and stock freeness were decreased. To elucidate this an electrostatic coagulation mechanism occurring between unadsorbed starch molecules and anionic colloidal silica was proposed. Unstructured colloidal silica showed greater improvement in retention than structured colloidal silica. Cationic corn starches with different degree of substitution and molecular weights were prepared and their effect as a constituent of Compozil system was also evaluated. By controlling the molecular weight and degree of substitution of cationic corn starch it was possible to achieve significant improvement in fines retention. Cationic corn starch with higher degree of substitution maintained its retention efficiency even when the stock conductivity was increased. Turbidity measurement technique was found to be a simple and useful method to measure the retention characteristics.

• 한국농공학회논문집
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• 제54권6호
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• pp.169-176
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• 2012

This study describes the estimation of upstream ungauged watershed streamflow using downstream discharge data. For downstream Dongchon (DC) and upstream Kumho (KH) water level stations in Kumho river basin ($2,087.9km^2$), three methods of Soil and Water Assessment Tool (SWAT) modeling, drainage-area ratio method and regional regression equation were evaluated. The SWAT was calibrated at DC with the determination coefficient ($R^2$) of 0.70 and validated at KH with $R^2$ of 0.60. The drainage-area ratio method showed $R^2$ of 0.93. For the regional regression, the watershed area, average slope, and stream length were used as variables. Using the derived equation at DC, the KH could estimate the flow with maximum 41.2 % error for the observed streamflow.