• Journal of Korea Water Resources Association
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• v.43 no.6
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• pp.533-541
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• 2010

It is basic for a flood prediction to calculate direct runoff from rainfall in a basin by the rainfall-runoff model. The direct runoff is calculated from rainfall excess or effective rainfall based on a rainfall-runoff model. The total rainfall minus rainfall loss equals rainfall excess with time. This loss can be treated equal to an infiltration loss under the assumption that the infiltration is a major one among the losses in the rainfall-runoff model. Practically obtaining the infiltration loss $\Phi$ index method, W index method or modified ones of these have been used. In this study it is assumed the loss of rainfall in a basin be a well-known Horton infiltration mechanism. And in case that the parameter set is given in the Horton infiltration model a procedure and assumption for calculating hourly infiltration loss and rainfall excess are offered and the results of its application are compared with those of $\Phi$ index method. By this study it is well shown the value of Horton infiltration function is exponentially decay with time as the Horton infiltration mechanism.

• Journal of Korea Water Resources Association
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• v.39 no.11 s.172
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• pp.977-984
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• 2006

The parameters in the Horton's model which has well known as typical infiltration model were determined by the use of the optimization technique. It was assumed the initial infiltration capacity in this model was related to the antecedent precipitation per 10 days with linear combination. And both the parameters of the ultimate infiltration capacity and the decay factor were determined uniquely on a basin. Thus the optimal model's parameters representative to a basin were obtained and the Horton's infiltration equations by rainstorm events were determined. The data of ten rainstorm events for this study were observed at the Jeonjeokbigyo station located at the Selmacheon experimental basin that was $8.5km^2$ wide in the Imjin river.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.107-111
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• 2009

The parameters in the Horton's model which has well known as typical infiltration model were determined by the use of the optimization technique. It was assumed the initial infiltration capacity in this model was related to the antecedent precipitation per 10 days with linear combination. And both the parameters of the ultimate infiltration capacity and the decay factor were determined uniquely on a basin. Thus the optimal model's parameters representative to a basin were obtained and the Horton's infiltration equations by rainstorm events were determined. The data of ten rainstorm events for this study were observed at the Jeonjeokbigyo station located at the Selmacheon experimental basin that was $8.5\;km^2$ wide in the Imjin river.

• Magazine of the Korean Society of Agricultural Engineers
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• v.24 no.1
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• pp.63-72
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• 1982

To maintain an optimum condition for the plant growth on upland soil, the irrigation planning after the natural rainfall should be given enormous considerations on the rainfall effectiveness. This study has been intended to develop the computer model for estimating the effec- tiveness of the rainfall. The computer model should also estimated the infiltration due to the rainfall and the soil moisture deficiency at the root zone of the plant. For this purpose, the experiments of infiltration using rainfall simulator and the observations of the change of soil moisture content before and after rainfall were carried out. Needed input data for the developed model include final infiltration capacity and field capacity of the soil, porosity of the top soil, root depth of the plant, rainfall intensity and duration, and the Horton's decay coefficient. Among the needed input data for the developed model, final infiltration capacity and Horton's decay coefficient were determined by the experiments of infiltration. And from the result of the experiments, it is found that there is a great correlation between initial infiltration capacity and initial moisture content. And it is also found that the infiltration due to rainfall can be estimated with the Horton's equation. The developed model was tested by the experimental data with two rainfall intensities. Tests were conducted on the different root depths at each rainfall. Observed and estimated effective rainfalls were found to have great correlation. The result of the experiments showed that the effectiveness of the rainfall were 100%, so the comparisons were conducted by the comsumption rates of infiltration at each depth. The developed model can be also used for estimating the deficiency of rainfall, if the rainfall is not sufficient to the needed soil moisture. But, test was not carried out.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.103-109
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• 2008

Precipitation on slope is separated into infiltration and outflow according to physical properties of soil and slope. However, the slope analysis is assumed that all precipitation are percolated. So, groundwater level is excessive tend to be calculated. In this paper, NRCS model and Horton models that have a suitability were used for agro-type analysis of Seoul station after precipitation was separated into infiltration and outflow. Also, gradient of slope was analyzed about seepage behavior and underground water level aspect through numerical analysis. After inclination correction, the estimated infiltration was compose of slopes much applied by domestic design standard. The change of groundwater level is appeared greatly as agro-type goes from D type to A type in the analysis results.

• Journal of the Korean GEO-environmental Society
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• v.21 no.12
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• pp.23-28
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• 2020

As a result of a suite of laboratory tests undertaken to suggest a rational method for the estimation of infiltration capacity, it is found that the infiltration rate tends to increase as the soil unit weight decreases while it tends to increase as the rainfall intensity increases. Comparative analyses for infiltration curves employing the reduction constant of initial infiltration capacity (α coefficient) that was suggested in this study has reasonably captured the time dependent variation of infiltration capacity. Consequently this study has presented an experimental model for the estimation of infiltration capacity to improve the Horton infiltration capacity curve that has been widely used for estimation of the infiltration capacity and amount of infiltration for its application to sandy soils.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.89-89
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• 2011

한 유역에서 유출 모형의 성공을 좌우할 수 있는 중요한 요소 중 하나는 강수 손실량(precipitation loss)을 결정하는 것이다. 손실량은 홍수 예측이나 수자원 평가를 위한 유출 모형의 주요 입력 자료가 된다. 만족할 만한 유출 모형을 구현하기 위해서는 손실량의 정확한 평가가 요구된다(Najafi, 2003). 총 강우량 중에서 손실량을 뺀 초과 강우량 또는 유효 강우량은 치수적 측면이든 이수적 측면에서 요구되는 직접 유출량(direct runoffs)에 상당하는 규모로서 유출 모형에서 매우 중요하다. 이제까지 많은 경우에 직접 유출되는 유효 강수량은 총강수량에서 주요 손실량 성분인 침투량을 감하여 산출하여 왔다. 이 때 침투량은 호우사상별로 적게는 유출량의 30%에서 많게는 100%까지 차지할 만큼 주요한 손실 성분으로 취급되었다(Chow, 1964 ; Singh, 1989). 침투량을 산정하기 위한 기존 모형내 포함되는 매개변수 값은 실용적으로 잘 정립되지 않았기 때문에 유출 모형에 실제 적용하는데 어려움이 있다. 한편 침투량 산정 모형 중에 Horton 모형은 가장 잘 알려져 있는 모형 중 하나이다(Horton, 1939 ; 1940). 후속 성과(Blake et al., 1968; Rawls et al., 1976)은 있었지만 모형내 매개변수 값을 결정해야 하는 실용상의 어려운 점이 있다(Singh, 1989). 그리고 국내 초과 강수량 산출 모형에 관한 연구사례가 다수(조홍제,1986; 남선우와 최은호, 1990; 정성원과 김승, 1991; 안태진 등, 2000; 박햇님과 조원철, 2002; 유주환, 2006) 있었지만 시간적으로 연속함수를 갖는 Horton 침투 모형을 실무적으로 이산화 하여 적용할 수 있도록 하는 방법의 절차 및 원칙이 제시되지 않아 유출 모형에 직접 적용하기 쉽지 않은 형편이다. 이에 본 발표에서는 한 유역에서 Horton 매개변수를 결정한 기존 연구(2006, 유주환)의 성과를 적용한 Horton 침투모형을 강수사상별 이산화한 시간별로 적용하는 절차와 적용 원칙을 소개하고자 한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.200-204
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• 2012

In engineering hydrology, an estimation of precipitation loss is one of the most important issues for successful modeling to forecast flooding or evaluate water resources for both surface and subsurface flows in a watershed. An accurate estimation of precipitation loss is required for successful implementation of rainfall-runoff models. Precipitation loss or hydrological abstraction may be defined as the portion of the precipitation that does not contribute to the direct runoff. It may consist of several loss elements or abstractions of precipitation such as infiltration, depression storage, evaporation or evapotranspiration, and interception. A composite loss rate model that combines four loss rates over time is derived as a lumped form of a continuous time function for a storm event. The composite loss rate model developed is an exponential model similar to Horton's infiltration model, but its parameters have different meanings. In this model, the initial loss rate is related to antecedent precipitation amounts prior to a storm event, and the decay factor of the loss rate is a composite decay of four losses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.412-424
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• 2019

In this study, the changes of the streamflow characteristics of the watershed were analysed depending on the infiltration methods of CAT. The study area, Boryeong-dam watershed located in Chungcheongnam-do area, has been suffered from severe drought in recent years and stabilized regarding on the storage rate through efforts such as constructing a channel connecting the upstream of Boryeong-dam from the downstream of the Geum river. In this study, the effects of soil infiltration parameters on the watershed streamflow characteristics were analyzed by the infiltration methods of CAT such as Rainfall Excess, Green&Ampt and Horton. And the parameter calibrations were conducted by SCEUA-P, a global optimization technique module of the PEST, the package for parameter optimization and uncertainty analysis, to compare the yearly variations of soil parameters for infiltration methods of CAT. In addition, the streamflow characteristics were analyzed for three infiltration methods by applying three different scenarios, such as applying calibrated parameters for every years to simulate the model for each years, applying calibrated parameters for the entire period to simulate the model for entire period, and applying the average value of yearly calibrated parameters to simulate the model for entire period.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.391-399
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• 1994

This study was carried out to investigate the water storage charateristics of surface soil by different forest floor conditions and to measure water storage capacity of forest Land at the Yeungnam University forest in Yongjang-ri, Nenam-myoen, Kyongju-gun, Kyongsangbuk-do. The study was conducted for 4 months, from June to September, 1993. The results were summarized as follows ; 1. Infiltration capacity of surface soil for each. forest floor condition was in the order : Oak forest>Oak forest removed $A_o$ layer>Pine forest removed $A_o$ layer>Pine forest>Bare land>Grasses. 2. The absolute values of infiltration capacity were increased as the rain intensity increased, while the order of infiltration capacity for each floor condition was not changed. 3. Infiltration capacity was highly correlated with surface soil hardness and todal pores. 4. Infiltration formula based on the Horton's could be estimated at each forest floor condition. 5. The model for water storage capacity of forest land expressed by infiltration capacity was estimated using total pores and soil hardness. This study indicates water storage capacity of different forest floor conditions depends on infiltration capacity. Using these formula, it was possible to calculate and estimate water storage capacity of forest land. Therefore, the result of this study will be helpful to increase water storage capacity of forest land and to manage water resources effectively.