• Title/Summary/Keyword: Infiltration model

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Behavior of Pore Water Pressure of Agricultural Reservoir According to Raising Embankment (농업용 저수지 둑 높이기에 따른 제체의 공극수압 거동)

  • Lee, Dal-Won;Lee, Young-Hak
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.3
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    • pp.11-17
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    • 2012
  • In this study, an experiment with large-scale model was performed according to raising embankment in order to investigate the cause of collapse by a change in water level of reservoir. Also, the settlement and pore water pressure by high water level and a rapid drawdown were compared and analyzed. After raising embankment for inclined core, there was no infiltration by leakage. For the vertical core, the pore water pressure showed a largely change by faster infiltration of pore water than in the inclined core. In a rapid drawdown, inclined core was remained stable but vertical core showed a largely change in pore water pressure. A settlement after a raising embankment showed a larger measure of settlement than before the raising embankment. The leakage quantity before a raising embankment and an inclined extension showed no leakage. Leakage in vertical extension was measured 160 $l$. From the result, a instrument system that can accurately estimate a change of pore water pressure shall be established for a rational maintenance and stabilization of raising embankment for agricultural reservoir.

Effect of Euterpe oleracea Mart. (acai berry) Extract on Skin Flap Survival in Mice

  • Jung, Sangbong;Kim, Jongsik;Kim, Eun-Joong;Rhee, Ki-Jong
    • Biomedical Science Letters
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    • v.25 no.3
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    • pp.282-287
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    • 2019
  • Skin flap necrosis remains a major complication of reconstructive surgery. Euterpe oleracea Mart., popularly known as "acai berry" contains hydroxybenzoic acid, antioxidant polyphenolics and anthocyanins. These and other compounds within the acai berry confer anti-inflammatory and anti-oxidative effects. In this current study, we evaluated the protective effect of acai berry extracts on survival of random-pattern skin flaps in a murine model by histologic analysis. ICR mice were subjected to skin elevation surgery and orally administered acai berry extract (100 mg/kg) daily for 7 days. Tissues were stained with hematoxylin-eosin or Masson's trichrome to observe tissue integrity and collagen deposition. In addition, $TGF-{\beta}$ and VEGF was stained by immunofluorescence to determine anti-inflammatory cell infiltration and neovascularization, respectively. We found a decrease in inflammatory cell infiltration and increase in collagen deposition in the acai berry extract treated mice compared to control mice. Immunofluorescence staining reveal a higher number of $TGF-{\beta}$ positive cells and enhanced VEGF staining in the acai berry extract treated mice. The results from this study indicate that oral uptake of acai berry extract can promote healing and survival of surgical skin flaps in mice providing an augmentative therapeutic approach to enhancing skin flap survival.

Comparison of Sediment Yield by IUSG and Tank Model in River Basin (하천유역의 유사량의 비교연구)

  • Lee, Yeong-Hwa
    • Journal of Environmental Science International
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    • v.18 no.1
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    • pp.1-7
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    • 2009
  • In this study a sediment yield is compared by IUSG, IUSG with Kalman filter, tank model and tank model with Kalman filter separately. The IUSG is the distribution of sediment from an instantaneous burst of rainfall producing one unit of runoff. The IUSG, defined as a product of the sediment concentration distribution (SCD) and the instantaneous unit hydrograph (IUH), is known to depend on the characteristics of the effective rainfall. In the IUSG with Kalman filter, the state vector of the watershed sediment yield system is constituted by the IUSG. The initial values of the state vector are assumed as the average of the IUSG values and the initial sediment yield estimated from the average IUSG. A tank model consisting of three tanks was developed for prediction of sediment yield. The sediment yield of each tank was computed by multiplying the total sediment yield by the sediment yield coefficients; the yield was obtained by the product of the runoff of each tank and the sediment concentration in the tank. A tank model with Kalman filter is developed for prediction of sediment yield. The state vector of the system model represents the parameters of the tank model. The initial values of the state vector were estimated by trial and error.

Effect of Amniotic Membrane to Reduce Postlaminectomy Epidural Adhesion on a Rat Model

  • Choi, Hyu-Jin;Kim, Kyoung-Beom;Kwon, Young-Min
    • Journal of Korean Neurosurgical Society
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    • v.49 no.6
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    • pp.323-328
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    • 2011
  • Objective : Epidural fibrosis and adhesion are the main reasons for post-laminectomy sustained pain and functional disability. In this study, the authors investigate the effect of irradiated freeze-dried human amniotic membrane on reducing epidural adhesion after laminectomy on a rat model. Methods : A total of 20 rats were divided into two groups. The group A did not receive human amniotic membrane implantation after laminectomy and group B underwent human amniotic membrane implantation after laminectomy. Gross and microscopic findings were evaluated and compared at postoperative 1, 3 and 8 weeks. Results : The amount of scar tissue and tenacity were reduced grossly in group of rats with human amniotic membrane implantation (group B). On a microscopic evaluation, there were less inflammatory cell infiltration and fibroblast proliferation in group B. Conclusion : This experimental study shows that implantation of irradiated freeze-dried human amniotic membrane reduce epidural fibrosis and adhesion after spinal laminectomy in a rat model.

Development of Water Saving Irrigation Method Using Water Balance Model (물수지 모형을 이용한 절수관개기법 개발)

  • Sohn , Seung-Ho;Chung , Sang-Ok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.46 no.5
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    • pp.3-11
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    • 2004
  • The objective of this study is to develop water saving irrigation method using water balance model in order to save rural water. Daily water balance components such as irrigation water, drainage water, effective rainfall, ET, and infiltration were measured in paddy fields. Model simulations were performed for different outlet heights and ponding depths. The outlet heights and the ponding depths are 2 cm, 4 cm, 6 cm, 8 cm, and 10 cm, respectively. Based on the simulation very shallow ponding depth of 2 cm with 10 cm outlet height showed the largest effective rainfall ratio and the smallest irrigation amount. Until the introduction of laser leveling dozer and automatic inlet control devices, it would be desirable to adopt 4cm ponding depth because of difficulty of land leveling and frequency of farmer's field visit. The results of this study will be applied in the paddy farming and can improve water use efficiency.

A study on the flood runoff analysis with TANK MODEL (탱크 모델에 의한 홍수(洪水) 유출량(流出量) 해석(解析)에 관(關)한 연구(硏究))

  • Hong, Chang-sun;Choi, Han-kuy
    • Journal of Industrial Technology
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    • v.3
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    • pp.95-101
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    • 1983
  • This study aims at the determination of the coefficienties of runoff and infiltration affecting runoff. The rating curve is more available than the peak flood runoff to determine flood control plan of flood control reservoir and the volume of hydroelectric power plant, or to make multipurpose dam. In hydrologic analysis and design, it is necessary to develop relations between precipitation and runoff, possible using some of the factors affecting runoff as parameters. In order to calculate the runoff discharge, the runoff process constituting elements are divided to the surface runoff, the subsurface runoff and the groundwater runoff. By comparing the computed hydrograph with the measured hydrograph, determinned the watershed TANK Model constant Varying the tank model constant for approximating the computed hydrograph to the measured hydrograph.

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Evaluation of Optimal Yield Using the Groundwater Model for a Small Rural Watershed (모형을 이용한 농촌 소유역 지하수 적정개발량 평가)

  • Park, Ki-Jung;Chung, Sang-Ok
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.646-650
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    • 2004
  • The purpose of this study is to determine the optimal groundwater yield for a small rural watershed, which is necessary for effective groundwater management. The study area$(3.89km^2)$ is located in Kyungpook Sangju Yangchon-dong and hourly groundwater level in an observation well is observed and the data are used to verify the visual MODFLOW model. The groundwater model is applied in the same area to obtain optimal yield for 1992 and 1994, 1982. The optimal yield in this experimental watershed ranged $12.5\%\;to\;14.0\%$ of the annual infiltration rate.

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Watershed Erosion Modeling with CASC2D-SED

  • Pierre Julien;Rosalia Rojas
    • Proceedings of the Korea Water Resources Association Conference
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    • 2002.05a
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    • pp.27-40
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    • 2002
  • Developed at Colorado State University, CASC2D-SED is a physically-based model simulating the hydrologic response of a watershed to a distributed rainfall field. The time-dependent processes include: precipitation, interception, infiltration, surface runoff and channel routing, upland erosion, transport and sedimentation. CASC2D-SED is applied to Goodwin Creek, Mississippi. The watershed covers 21 $\textrm{km}^2$ and has been extensively monitored both at the outlet and at several internal locations by the ARS-NSL at Oxford, MS. The model has been calibrated and validated using rainfall data from 16 meteorological stations,6 stream gaging stations and 6 sediment gaging stations. Sediment erosion/deposition rates by size fraction are predicted both in space and time. Geovisualization, a powerful data exploration technique based on GIS technology, is used to analyze and display the dynamic output time series generated by the CASC2D-SED model.

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Calculation of Effective Rainfalls in Paddy Fields Using Large Lysimeters (대형 Lysimeter를 이용한 논에서의 유효우량의 계산)

  • 최승만;정하;최진용
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.75-80
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    • 1999
  • The water requirement of crops in paddy fields is composed of evapotranspiration and infiltration. The determination of effective rainfall has the great significance for the irrigation managements and system design. There are numerous methods to estimate effective rainfall. The FreeBoard Model(FBM), ond of them , is popular because it can describe the algorithm of effective rainfal with simplified and general formation. The purpose of this study is to evaluate effective rainfall by field measurement , to compare this closely with the results from freeboard model and modified freeboard model , and to find out which of two models is more consistent with the results obtained by measurements.

Apply Low Impact Development for the reduction of runoff using SWMM model (SWMM 모형을 이용한 서암동지구에서의 유출수 저감을 위한 저영향개발기법 적용)

  • Woo, Won Hee;Lee, Tae Woo;Park, Youn Shik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.218-218
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    • 2017
  • Urbanization increases impervious area and decreases the water quantity infiltrating into soil layers. This leads to lack of ground water, it could be possibly problematic for agricultural water for crop growth in lower basins, reducing not only ground water but also streamflow quantities. One such approach to minimize the impact of urbanization is to apply low impact developments (LIDs). LIDs are to decrease the percentage of impervious area so that infiltration rate is increased, there is a need to simulate the LIDs prior to the construction. LIDs in Storm Water Management Model (SWMM) are limited to be seven types, however it is often required to simulate LIDs more than seven types. Therefore an approach to apply eleven LIDs is provided in the study, updating the model parameters. A scenario containing eleven LIDs was given by the environmental decision makers, the effect of LIDs were simulated with the expected annual costs considering establishment and maintenance costs.

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