• Title/Summary/Keyword: infiltration rate

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Analysis of rainfall infiltration characteristics for unsaturated soils using a column test equipment (모형실험장치를 이용한 불포화토의 강우 침투특성 분석)

  • Park, Kyu-Bo;Chae, Byung-Gon;Kim, Kyeong-Su
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.736-742
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    • 2010
  • This study was conducted to characterize on the relationships of rainfall intensity and infiltration rate of rainfall dependent on unit weight change in the gneissic weathered soil by a column test equipment. In this study, volumetric water content and pore water pressure were measured using TDR sensors and tensiometers at regular time intervals. Rainfall conditions including continuous rainfall and repeated rainfall were selected in order to know the effect of antecedent rainfall. In the condition of rainfall intensity 20mm/h and the unit weights of soil as $1.35g/cm^3$, $1.55g/cm^3$ and $1.61g/cm^3$, average rainfall infiltration rate was $2.814{\times}10^{-3}cm/sec$, $1.969{\times}10^{-3}cm/sec$ and $1.252{\times}10^{-3}cm/sec$ respectively. The higher rainfall intensity and lower unit weight of soil, the faster average infiltration rate. Overflow in the column was happened except rainfall condition of rainfall intensity 20mm and soil unit weight $1.35g/cm^3$. Increasing the soil unit weight, overflowed water was increased and occurrence time was faster.

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Experimental Research of Window Air Tightness and Opening Force with Respect to Mohair Number, Clearance and Shortened Length (모헤어 개수, 틈새 길이 및 축소된 길이의 창문 기밀성 및 개폐력에 대한 실험적 연구)

  • Kim, Seung Jae;Park, Jong Jun;Kim, Young Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.30 no.4
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    • pp.195-203
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    • 2018
  • Mohair is widely used as an airtight material for filling the gap between a window frame and sash. The purpose of this study is to investigate infiltration rate and opening force of sliding windows according to the mohair installation conditions. Infiltration experimental apparatus was set up, and the experimental results were applied to windows to find a correlation between infiltration rates and opening forces. When 4 rows of mohair were installed, the infiltration rate increase became 27.1% per clearance length increase of 1 mm, and the infiltration rate decrease became 5.7% per shortened length increase of 0.1 mm. For 4 rows of mohair, the opening force decreased by 28.2% as the clearance increased by 1 mm, and it increased by 9.3% as the shortened length increased by 0.1 mm.

Improvement of Infiltration by Applying Hybrid Low Impact Development (LID) Infiltration Pipes in an Urban Area (도시에서 하이브리드 LID 침투관 설치에 따른 침투량 향상)

  • Han, Kyung Soo;Park, Yong Soon
    • Ecology and Resilient Infrastructure
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    • v.3 no.2
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    • pp.126-129
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    • 2016
  • The risk of flooding and groundwater depletion is increasing due to the increase of impervious area in an urban area that reduces the volume of infiltration and increases the outflow of rainwater. The objective of this study is to examine the impact of installation of roadside tree protectors with infiltration pipes in terms of the change of the infiltration rate. Through this study, it has been attested that roadside tree protectors with infiltration pipes increased the infiltration rate and decreased water level on the ground, and could be applied in an urban area as the low impact development (LID) facilities.

A Study on the Calculation Method of Infiltration for Detached Houses (기존 단독주택의 침기량 산정법에 관한 연구)

  • Kim, Giltae;Yoo, Jung-Hyun;Hwang, Ha-Jin;Kim, Kyoung-Sik
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.25 no.9
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    • pp.493-498
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    • 2013
  • The purpose of this study is to find the infiltration of detached houses, for energy consumption analyses. The pressurization and depressurization method is used to determine infiltration. Blower door tests are expressed in terms of ACH 50, which stands for the hourly air change rate at 50 Pa of fan pressure. The ACH 50 of existing Detached Houses ranges from 5 to 50. Air infiltration is related to construction year and accuracy, maintenance conditions, and so on. When estimating the infiltration of random detached houses, the year used can be the base value of the infiltration rate from 0.25 to 2.0 times/h. The maintenance conditions, construction accuracy and repair affect the air infiltration 0 to 0.5 times/h, 0 to 0.3 times/h, 0 to 1 times/h, respectively.

The Effect of Pain Relieving Intervention During Infiltration among Gamma Knife Surgery Patients for Stereotactic Frame Fixation (감마나이프 수술 환자의 정위적 틀 고정을 위한 침윤 마취 시 통증 완화 중재의 효과)

  • Jang, Young Jun;Kim, Hyeon Ok
    • Journal of Korean Academy of Nursing
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    • v.48 no.2
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    • pp.221-231
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    • 2018
  • Purpose: This study aimed to compare the effects of three interventions on pain, blood pressure, and pulse rate during infiltration anesthesia in patients about to undergo gamma knife surgeries. Methods: The three interventions employed in a university-affiliated Hospital in J City, South Korea were as follows: EMLA cream plus Vapocoolant spray (Vapocoolant, n=30), EMLA cream plus 10.0% Lidocaine spray (Lidocaine, n=30), and EMLA cream only (EMLA, n=30). The equivalent control-group pre test - post test study design was used. Pain was assessed subjectively using the numeric rating scale (NRS) and objectively using a Galvanic Skin Response (GSR) tester. NRS scores were assessed after infiltration anesthesia and the GSR was assessed during infiltration anesthesia. Blood pressure and pulse rate were assessed twice: before and after infiltration anesthesia. Data were collected between August 3, 2016 and March 24, 2017. Results: NRS scores after infiltration anesthesia and the GSR during infiltration anesthesia were significantly lower in the Vapocoolant group than in the Lidocaine and EMLA groups (F=13.56, p<.001 and F=14.43, p<.001, respectively). The increase in systolic blood pressure (F=4.77, p=.011) and in pulse rates (F=4.78, p=.011) before and after infiltration anesthesia were significantly smaller in the Vapocoolant group than in the Lidocaine and EMLA groups; however, no significant differences were observed in diastolic blood pressures (F=1.51, p=.227). Conclusion: EMLA cream plus Vapocoolant spray was the most effective intervention to relieve pain and to lower increase in systolic blood pressure and pulse rate caused by infiltration anesthesia for stereotactic frame fixation. Thus, application of Vapocoolant spray in addition to EMLA cream is highly recommended as a nursing intervention for patients undergoing gamma knife surgeries.

Infiltration Rate of Some Upland Soils in Korea (우리나라 밭토양의 수분침투속도(水分浸透速度)에 관하여)

  • Jung, Y.S.;Ryu, K.S.;Im, J.N.
    • Korean Journal of Soil Science and Fertilizer
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    • v.13 no.1
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    • pp.1-6
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    • 1980
  • The infiltration rates of the upland soils on hill side slope were investigated in situ using rainulator of which rainfall intensity was 100mm/hr. The soil moisture profile after the water infiltration was compared with that calculated from Youngs' equation. The results obtained are as follows: 1. Time required for infiltration rate to reach constant during rainfall was 15 to 25 min. The infiltration rate measured after 30 min was considered to be final infiltration rate. 2. The final infiltration rates of clay soils were lower than 10mm/hr., loamy soils 10 to 20., coarse loamy soils 20 to 30, and sandy soils higher than 30mm/hr., respectively. 3. The saturated hydraulic conductivity of the surface soil of Samgag sandy loam was 0.47mm/min., Songjeong clay loam0.16 mm/min., and Jeonnam silty clay loam 0.14mn/min., respectively. 4. The soil moisture profile calculated from Young's equation was in close agreement with measured in situ.

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An Analysis of Runoff Reduction Effect of Infiltration Facilities in Urban Area (도시유역에서 침투시설의 우수유출저감효과 분석)

  • Lee, Jae-Joon;Kim, Ho-Nyun;Kwak, Chang-Jae;Lee, Sang-Won
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.628-631
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    • 2007
  • One of the structural measures for the peak flow reduction is infiltration facilities. There are many types in infiltration facilities - infiltration basin, trench, bed, porous pavement, percolated subdrain, dry well. In this study runoff reduction effect of infiltration trench is analyzed by WinSLAMM. Runoff reduction effect is investigated by each design rainfall and temporal pattern of rainfall particularly. The biggest reduction is shown in Yen and Chow's temporal pattern of design rainfall and the smallest reduction is shown in Huff's first quartile pattern. Runoff reduction rate is presented about 6 to 14 percentage, and the larger return period, the smaller runoff reduction rate.

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Monitoring of artificial infiltration using electrical resistivity method

  • Nakazato Hiroomi;Kuroda Seiichiro;Okuyama Takehiko;Takeuchi Mutsuo;Park Mikyung;Kim Hee Joon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.362-369
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    • 2003
  • A infiltration experiment of river water has been conducted to evaluate the applicability of electrical resistivity monitoring methods in an area containing gravelly deposits in Nagaoka, Japan. Apparent resistivity data, which are inverted to obtain the resistivity distribution, are measured with a newly developed system. This system can collect 490 data in an hour and be controlled with PC to store the data. Subsurface resistivity sections, which are obtained from two-dimensional nonlinear inversion of time-lapse apparent resistivity data, enable us to estimate the direction of the flow and the rate of infiltration. The infiltration rate is estimated to be $4.4{\times}10^4m/s$ in the early stage of the experiment when the infiltration process is dominant.

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Rail Transport Operation Control for Railway Embankment under rainfall (강우시 성토사면의 열차운전규제기준)

  • Kim, Hyun-Ki;Shin, Min-Ho;Choi, Chan-Yong
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.225-232
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    • 2009
  • Infiltration of rainfall causes railway slopes to be unstable and may result in failure. Basic relationship between the rainfall and stability of railway embankment is defined to analyze its stability by rainfall. An experimental study for defining of infiltration rate of rainfall into slope is conducted in the lab. The results of Rainfall infiltration show that rainfall infiltration is not equal to infiltration as like reservoir because rate of rainfall infiltration is controlled by slope angle. Based on these results, boundary condition of rainfall is altered and various numerical analysis are performed. The variation of shear strength, the degree of saturation and pore-water pressure for railway slope during rainfall can be predicted and the safety factor of railway slope can be expressed as the function of rainfall amount, namely rainfall index. And suggested rainfall index is compared with the rail transport operation control which is used in KORAIL. It is judged that this rainfall index can be a good tool for the rail-transport operation control.

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An Experimental Study on Infiltration Characteristics of Facilities for Reducing Runoff Considering Surface Materials According to Housing Lot Developments (택지개발에 따른 표면재료를 고려한 우수유출저감시설의 침투 특성에 관한 실험 연구)

  • Im, Janghyuk;Song, Jaiwoo;Park, Sungsik;Park, Hosang
    • Journal of the Korean GEO-environmental Society
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    • v.8 no.5
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    • pp.47-55
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    • 2007
  • The increment of impermeable land area due to widespread land development caused the adverse impact on urban disaster prevention because it could decrease the peak rate of runoff as well as increase the runoff and peak flow during rainy period. To date, little research has been conducted on the infiltration characteristics and quantitative analysis because of their highly dependence on construction method, paving material, surface permeability, and field condition. Hence, this study was performed to investigate the infiltration characteristics of runoff-reducing facilities according to the type of paving material, which were examined using experimental apparatus with varying paving material and rainfall intensity, and thus to provide fundamental research data for runoff-reducing infiltration facilities. In this study, the infiltration characteristics were examined under the rainfall intensity of 20, 30, 50, 80, 100, 200 mm/hr for a variety type of paving materials such as concrete, asphalt, sand, grassland, and permeable paving material. The infiltration rate for permeable paving material was observed to be more than 93% under the condition of less than 200 mm/hr of rainfall intensity. For the compacted earth and grassland, the ultimate infiltration rate was estimated to be about 13% to 67%. The permeable paving material was concluded to be the most appropriate one for the runoff-reducing infiltration facilities because it has more favorable advantages than others in the light of infiltration volume, disaster prevention, and river training.

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