• 한국관개배수논문집
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• 제14권1호
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• pp.41-49
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• 2007

In this study, Kajiyama equation and SWAT model were used to estimate the available water resources from 1967 to 2003 at the small scale watershed, located in Dongnae-Myeon, Chunchen, Gangwon. The annual average streamflow for dry years estimated using the Kajiyama equation and the SWAT model were $2,593,779m^3$ and $2,579,162m^3$. The annual average streamflow for wet years were $7,223,804m^3$ and $7,035,253m^3$, respectively. The annual arrange streamflow for the entire 36 year period were $14,868,601m^3$ and $14,214,292m^3$, respectively. The coefficient of determination ($R^2$) and the Nash-Sutcliffe coefficient for comparison between Kajiyama and SWAT were 0.90 and 0.79, respectively. The comparison indicates that the Kajiyama equation and the SWAT model can be used to estimate the streamflow at th study watershed with reasonable accuracy, although the estimated values were not compared with measured streamflow data, which is not available at the small scale study watershed. However, the Kajiyama equation is recommended for estimating available water resources at Dongnae-Myeon watershed because of its ease-of-use and reasonable accuracy compared with the SWAT model, requiring numerous model input and expensive GIS software in operating the model

• 대한환경공학회지
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• 제31권5호
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• pp.358-363
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• 2009

유역관리 계획이 하천 수질에 미치는 영향을 분석하기 위하여 HSPF (Hydrological Simulation Program-Fortran) 모델을 경안천에 적용하였다. BASINS 3.1 GIS 프로그램에 DEM (Digital Elevation Model), 토지이용도, 하천도, 환경기초시설 등을 입력하여 경안천 유역을 총 57개 소유역으로 구분하고 모델 입력 자료를 산출하였다. 먼저 관측된 기상 및 하천 수량 자료를 이용하여 수문 모델의 타당성을 확인한 후 수질 모델을 보정하고 검증하였다. 적용한 수질은 수온, DO, BOD, $NO_3-N$, $NH_3-N$, Org-N, TN 그리고 TP이며, 대부분의 경우 측정치와 예측치가 적절히 일치하였다. 보정 및 검증 완료된 모델을 활용하여 소유역의 수질관리 방안에 따른 경안천 본류의 수질개선 효과를 분석하였다. 적용한 시나리오는 세 가지로, 첫째, 유역관리 활동을 통한 지천 수질개선, 둘째, 환경기초시설의 확충과 처리수질 향상, 그리고 셋째, 이 두 가지를 동시에 적용하는 것이다. 예측결과에 따르면 환경기초시설 확충과 처리수질 향상이 유역관리를 통한 지천 수질개선보다 효과적인 것으로 나타났다. 경안천이 만족할 만한 수질로 개선되기 위해서는 두 가지 방안이 모두 적용되어야 하는 것으로 나타났다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.693-697
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• 2009

Physically-based WEPP watershed version was applied to a watershed, located at Jawoon-ri, Gangwon with very detailed rainfall data, rather than daily rainfall data. Then it was validated with measured sediment data collected at the sediment settling ponds and through overland flow. The $R^2$ and the EI for runoff comparisons were 0.88 and 0.91, respectively. For sediment comparisons, the $R^2$ and the EI values were 0.95 and 0.91. Since the WEPP provides higher accuracies in predicting runoff and sediment yield from the study watershed, various slope scenarios (2%, 3%, 5.5%, 8%, 10%, 13%, 15%, 18%, 20%, 23%, 25%, 28%, 30%) were made and simulated sediment yield values were analyzed to develop appropriate soil erosion management practices. It was found that soil erosion increase linearly with increase in slope of the field in the watershed. However, the soil erosion increases dramatically with the slope of 20% or higher. Therefore special care should be taken for the agricultural field with higher slope of 20% or higher. As shown in this study, the WEPP watershed version is suitable model to predict soil erosion where torrential rainfall events are causing significant amount of soil loss from the field and it can also be used to develop site-specific best management practices.

• 한국환경농학회지
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• 제19권5호
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• pp.419-425
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• 2000

Rating curve method and SWMM (Storm Water Management Model) were applied to estimate pollutant loading from Hwa-Ong watershed in Kyunggi-Do. Rating curves were derived from sampling sites and applied to the whole watershed. SWMM version 4.4 was calibrated by field data of sampling sites and applied to the whole watershed. The pollutant loading estimated by rating curve was slightly higher than the one by SWMM, but the difference was not significant considering diffuse pollution characteristics of wide variation. Land use effect of the subcatchments could not be incorporated logically in rating curve method and difficulty in extrapolation was experienced, therefore, the estimate by rating curve method was thought to be less confident. SWMM was satisfactory in estimation of pollution loading, and its great flexibility worked well to describe complex nonurban land uses. Neither of them could exactly describe complex natural phenomena, but SWMM was preferred in this study due to its flexibility and logical hydrologic processes including land use effects. Use of reasonable watershed model rather than rating curve method for watershed pollutant loading estimate can be more practical and is recommended.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.540-545
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• 2005

Large scale projects of sea-land reclamation have been practiced mainly to enlarge farmland in Korea. Most projects produced estuarine reservoir with dike construction, which might result in water quality problems due to block of natural flowing of stream water to the sea. Applicability of a widely accepted watershed-based water quality assessment tool (BASINS) and its associated watershed model was evaluated on the Hwaong watershed in Korea. BASINS was found to be a convenient and powerful tool for assessment of watershed characteristics, and provided various tools to delineate the watershed into land segments and river reaches, reclassify land use, and parameterize for HSPF simulation. WASP5 is a general purpose modeling system for assessing the fate and transport of conventional and toxic pollutants in surface water bodies. This study involved selection and linkage of available models to be used as a tool in evaluating the effects of BMPs for control on reservoir water quality. Overall,.Linkage of BASINS/HSPF and WASP5 was applicable and found to be a powerful tool in pollutant loading estimation from the watershed and reservoir, and its use is recommended.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.289-292
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• 2002

In this study, a topography based hydrologic model (TOPMODEL) was tested on the Anseong-cheon watershed. Pit in watershed was removed by liner trend surface interpolator. The DTM Analysis program is used to derived a distribution of ln($a/tan{\beta}$) values from DEM (Digital Elevation Model) using the MDF (Multiple Direction Flow) algorithm of Quinn et al (1995). Current TOPMODEL program limits are number of time step, ln($a/tan{\beta}$) increment, delay histogram ordinate and size of subcatchment pixel maps. Therefore, TOPMODEL is not suitable for application of large watershed. Muskingum method and watershed division enhance grid pixel resolution for rainfall-runoff simulation accuracy.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.403-407
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• 2001

For the water quality management of stream and lake, it is important to estimate and control nonpoint source loading to meet the water quality standard. So, integrated watershed management is required. BASINS is a multipurpose environmental analysis system for use by regional, state, and local agencies in performing watershed and water quality based studies. BASINS was developed by the USEPA to facilitate examination of environmental information, to support analysis of environmental systems and to provide a framework for examining management alternatives. BASINS contains HSPF which is one of the watershed runoff model. By using HSPF, nonpoint source loading from upper stream watershed was estimated. As a result, the simulated runoff was in a good agreement with the observed data and indicated reasonable applicability for whole watershed.

• 환경영향평가
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• 제20권4호
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• pp.489-496
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• 2011

The water pollution such as oil spill from stream and river because of car accidents have been frequent cases in the watershed of Dam. However we don't have any simulation methods about flow modeling on the watershed and stream tree. In this study aims to analyze water pollution accidents area on impact range for ANDONG-Dam. The focused watershed and the risk range of path analysis model was designed by GIS database. The frequency of transportation accidents which may occur from road accidents in the level of quantitative and qualitative analysis to map flow analysis using ArcHydro Model and Open Geospatial Consortium(OGC) API. and the path way from the accident point to the reservoir stayed on the path was simulated. The area of risk accessment index was displayed with cell and grid of dam area.

• 물과 미래
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• 제25권3호
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• pp.97-104
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• 1992

분포형 수문모형은 유역의 공간적 특성과 강우양상을 고려한 강우-유출량의 추정을 위한 효과적인 수단으로 사용되고 있다. 본 연구는 소유역에서의 단기 홍수유출 해석을 위하여 유한요소 수치기법을 수문모형에 도입하고, 이를 소유역을 대상으로하여 유한요소모형의 적용성을 검토하고자 하였다. 모형에 적용된 자료는 2.8km2 인 연화천유역과 1991년 수문자료중 14개의 강우사상이 사용되었으며, 관측 및 모의 발생된 수문량을 비교하였다.

• 한국환경과학회지
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• 제9권1호
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• pp.13-18
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• 2000

The purpose of this study is to estimate the low-flow statistics at the mountainous watershed. The formulation for the estimation of the design low-flow statistics was obtained by means of a hydraulic approach applied to a simple conceptual model for a mountainous watershed. Three of the independent variables associated with the low-flow statistics is watershed area(A), average basin slope(S) and the base flow recession constant(K); Watershed area was measured from topographic maps and average basin slope is approximated in this study using Strahler's slope determining method. And base flow recession constant computed using Vogel and Kroll's method. Unfortunately, this method is usually unavailable at ungaged sites. In this study, recession constant at ungaged sites is estimated using graphical regression method used by Giese and Mason. The model for estimating low-flow statistics were applied to all 61 catchments in the Sumjin, Mankyung basin.