• 한국농공학회지
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• 제35권1호
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• pp.40-49
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• 1993

The Objectives of this paper were to develop a modified tank model that is capable of simulating daily streamflow from a small watershed using daily watershed evapotranspiration and to test the applicability of the model to different watersheds. Tank model was restructured to consist of three series of tanks, each of which may mathematically reflect watershed runoff mechanisms from different components of surface runoff, interflow, and baseflow. And pan evaporation was correlated to potential evapotranspiration estimated from a combination method, and was multiplied by monthly crop and landuse coefficients, and watershed storage coefficient to estimate the watershed evapotranspiration losses. Ten watersheds were selected to calibrate model parameters that were defined using an optimization scheme, and the results were correlated with watershed parameters. Simulated daily runoff was compared to the observed ones from the tested watersheds. The simulating results were in good agreement with the observed values when optimal and calibrated parameters were used. Ungaged conditions were also applied to compare simulated values to the observed. And the results were in fair conditions for all the tested watersheds which differ considerably in their sizes, landuse types, and physiological features.

• 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.

• 한국정보전자통신기술학회논문지
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• 제4권4호
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• pp.225-230
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• 2011

본 논문에서는 깊이정보에 기반한 watershed와 영역병합 알고리즘을 이용한 얼굴영역 분할 방법을 제안하였다. 얼굴영역 검출은 영역 분할 단계, 초기 화소 영역 검출 단계, 영역 병합의 세 단계로 구성된다. 입력된 컬러 영상은 제안된 알고리즘에 의해 균일한 작은 영역들로 분할된다. 색도정보와 에지 구속 조건을 사용하여 균일한 영역들을 결합함으로써 얼굴영역을 검출한다. 제안한 알고리즘은 색도정보나 에지정보만을 사용하는 기존 방법에서의 문제점을 해결하였다. 제안한 알고리즘의 성능을 평가하기 위해 컴퓨터 시뮬레이션을 하였으며 정확한 얼굴 영역을 분할할 수 있었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.218-218
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• 2015

Urbanization and waterworks construction in natural watershed have been causing higher flood risks in lowland areas. Detention basins have become one of the most efficient fundamental instruments for storm water and environmental management at watershed scale. Nowadays, there are many studies coupled numerical methods of flood routing with optimization algorithms to investigate factors that impact on the efficiency of detention basins in flood reduction in a watershed, such as detention basin location, size, and cost and watershed characteristics. Although these couplings have been become more widespread but cumbersome computation and hydraulic data requirement still are their limitations. To tackle the procedure efforts due to numerical integration and data collection, simple approach is proposed to primarily estimate effects of detention basins. The approach basis is the linear system theory applied to the solution of hydrologic flood routing. The paper introduces an analytical method for estimating detention effects deriving by recent studies and innovatively analyses this equation on fractal perspective. Then, an optimization technique is performed by applying harmony search algorithms (HSA) to optimize efficiency of detention basins at watershed scale. The location and size of upstream detention basin are simultaneously obtained. Finally, the proposed methodology, practically applied for a real watershed in Kan river, Iran.

• 한국물환경학회지
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• 제27권2호
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• pp.159-166
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• 2011

The use of land cover was sharply changed during 1975~2007 in the Kyungan watershed $(561.12 km^2)$. The changes occurred over an area of more than $227.65 km^2$ during the overall period at changing rates of 1.04% per year for water area, 1.79% per year for residential area, 2.99% per year for bare area, 3.03% per year for wetland area, 3.04% per year for grass area, 0.87% per year for forest and 2.32% per year for agriculture area. Water, residential, bare and wetland areas increased, while grass, forest and agriculture areas decreased during the last 32 years. BOD concentrations of representative sites for each sub-watershed continuously increased until the early 2000s as residential area increased with the highest discharged load, but decreased after the mid 2000s except upper Kyungan watershed. Such decline appears to be associated with the planning of Total Maximum Daily Load management for Gwangju city and expansion of waste water treatment plant. It is necessary to control land use/cover changes of the upper watershed and to prepare appropriate watershed management system for improvement in river environment including water quality, stream flow and bio-diversity.

• 환경영향평가
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• 제24권5호
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• pp.397-406
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• 2015

2013년 시행된 유역하수도정비계획에서는 유역별 수질상황을 고려하여 하수처리시설별 방류수 수질 준수농도(기준)를 별도로 적용하는 것이 가능하다. 유역의 중권역 목표기준 또는 수질오염총량관리 목표수질을 달성하기 위하여 유역하수도 제도 도입에 따라 유역 내 지역별 시설규모별 하수처리시설에 대한 방류수 수질 준수농도(안)을 설정하는 것이 필요하다. 유역환경청에서 수립하고 있는 유역하수도정비계획 수립 시 공공하수처리시설 방류수 수질 준수농도(기준)을 설정하는데 있어 II지역인 미호천유역의 경우 BOD 5 mg/L에서 3 mg/L, II III지역이 혼재되어 있는 영산강 상류유역의 경우 BOD 5~10 mg/L에서 3 mg/L로, IV지역인 안성천유역의 경우 BOD 10 mg/L에서 5 mg/L로 일률적으로 강화하도록 계획하고 있다. 이렇게 일률적으로 정하고 있는 준수농도에 대해 하수 처리기술, 유역특성을 고려한 유역하수도 공공하수처리시설의 방류수 수질 준수농도를 설정하는 방법을 제시하는 것이 필요하다. 본 연구에서는 공공하수처리시설 방류수 수질 준수농도 강화(안)을 설정할 때 이 강화된 준수농도가 공공수역 수질에 미치는 영향을 평가하여 어떤 강화(안)이 유역관리에 좀 더 효과적인지 고찰하였다.

• 한국물환경학회지
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• 제24권4호
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• pp.488-498
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• 2008

Soil and Water Assessment Tool (SWAT) model have been widely used in simulating hydrology and water quality analysis at watershed scale. The SWAT model extracts topographic feature using the Digital Elevation Model (DEM) for hydrology and pollutant generation and transportation within watershed. Use of various DEM cell size in the SWAT leads to different results in extracting topographic feature for each subwatershed. So, it is recommended that model users use very detailed spatial resolution DEM for accurate hydrology analysis and water quality simulation. However, use of high resolution DEM is sometimes difficult to obtain and not efficient because of computer processing capacity and model execution time. Thus, the SWAT Topographic Feature Extraction Error (STOPFEE) Fix module, which can extract topographic feature of high resolution DEM from low resolution and updates SWAT topographic feature automatically, was developed and evaluated in this study. The analysis of average slope vs. DEM cell size revealed that average slope of watershed increases with decrease in DEM cell size, finer resolution of DEM. This falsification of topographic feature with low resolution DEM affects soil erosion and sediment behaviors in the watershed. The annual average sediment for Soyanggang-dam watershed with DEM cell size of 20 m was compared with DEM cell size of 100 m. There was 83.8% difference in simulated sediment without STOPFEE module and 4.4% difference with STOPFEE module applied although the same model input data were used in SWAT run. For Imha-dam watershed, there was 43.4% differences without STOPFEE module and 0.3% difference with STOPFEE module. Thus, the STOPFEE topographic database for Soyanggang-dam watershed was applied for Chungju-dam watershed because its topographic features are similar to Soyanggang-dam watershed. Without the STOPFEE module, there was 98.7% difference in simulated sediment for Chungju-dam watershed for DEM cell size of both 20 m and 100 m. However there was 20.7% difference in simulated sediment with STOPFEE topographic database for Soyanggang-dam watershed. The application results of STOPFEE for three watersheds showed that the STOPFEE module developed in this study is an effective tool to extract topographic feature of high resolution DEM from low resolution DEM. With the STOPFEE module, low-capacity computer can be also used for accurate hydrology and sediment modeling for bigger size watershed with the SWAT. It is deemed that the STOPFEE module database needs to be extended for various watersheds in Korea for wide application and accurate SWAT runs with lower resolution DEM.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.370-375
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• 1998

The objectives of this study are to evaluate the applicability of SCS TR-20 model for small ungauged watershed, to show the behavior of the model with variation of topography in watershed, and to evaluate the storage effect of paddy field for flood flow. For this purpose, simulated data from the model were compared with the observed flood data at two sites (HS#3, HS#4) in Balan watershed. From the comparison between simulated and observed data, it was found that the model is applicable to this watershed.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
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• pp.59-62
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• 2002

Watershed Segmentation with Multiple Merging Conditions in Region Growing Process The watershed segmentation method holds the merits of edge-based and region-based methods together, but still shows some problems such as over segmentation and merging fault. We propose an algorithm which overcomes the problems of the watershed method and shows efficient performance for .general images, not for specific ones. The algorithm segments or merges regions by thresholding the depths of the catchment basins, the similarities and the sizes of the regions. The experimental results shows the reduction of the number of the segmented regions that are suitable to human visual system and consciousness.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2000년도 추계학술발표논문집
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• pp.183-186
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• 2000

영상 분할(image segmentation)은 주어진 영역에서 의미 있는 영역만을 분리해 내는 과정으로 컴퓨터 비젼 분야에 있어 매우 중요한 단계로 취급되어 진다. 본 연구에서는 기존의 영상 분할 알고리즘들의 문제점을 해결하고자 단계적인 marker 영상을 적용한 watershed 알고리즘을 제안하였다. 제안한 방법은 단계적인 level의 조절에 따라 분할의 정도를 선택할 수 있으며 watershed 알고리즘의 특성인 정확한 물체 검출의 장점들 살릴 수 있다.