• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.184-185
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• 2005

• 한국수자원학회논문집
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• 제45권2호
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• pp.203-215
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• 2012

본 연구의 목적은 도시개발의 영향을 평가하고 물순환 개선시설의 적절한 배치를 설계하기 위한 물순환 해석 모형을 개발하는 것이다. 개념적 매개변수를 사용하는 기존의 집중형 수문모형으로는 도시개발로 인한 토지이용 변화 등의 유역 특성 변화를 적절히 모의하는데 한계가 있으며, 최근 활발히 연구되고 있는 분포형 수문모형은 입력자료 구축 및 모형 구동에 많은 시간과 노력이 필요하여 다양한 도시설계 대안을 평가하기에는 적절하지 못하다. 유역 물순환 해석 모형(Catchment hydrologic cycle Analysis Tool, 이하 CAT)은 이러한 배경을 토대로 개발된 물리적 매개변수 기반의 링크-노드 방식의 물순환 정량화 모형이다. CAT은 기존 개념적 매개변수 기반의 집중형 수문모형과 물리적 매개변수 기반의 분포형 수문모형의 장단점을 최대한 보완하여, 도시유역 개발 전 후의 장 단기적인 물순환 변화 특성을 정량적으로 평가하고 물순환 개선시설의 효과적인 설계를 지원하기 위한 물순환 해석 모형이다. 개발된 모형의 평가를 위하여 설마천 유역을 대상으로 모의를 수행하였으며 출구점인 전적비교의 6개년(2002~2007) 동안의 시간별 하천 유출량 자료를 이용하여 모형의 보정(2002~2004)과 검정(2005~2007)을 실시한 결과, 보정과 검정기간의 Nash-Sutcliffe 모형효율계수는 각각 0.75와 0.89로 나타났다.

• 대한공간정보학회지
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• 제21권3호
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• pp.37-46
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• 2013

유역의 수문학적 유사성 평가는 계측지역의 홍수량 정보를 미계측 유역에서 활용하는 지역화 연구의 기초로서 다양하게 연구되고 있다. GIS 기반의 유역 특성인자를 기반으로 대표적인 수문학적 거리산정법을 활용하여 금강유역의 25개 소유역을 대상으로 유역 그룹화를 수행하고, 이를 유황곡선의 관련 계수(저류계수, 갈수계수, 홍수계수, 풍수계수, 유황계수, 하상계수)를 바탕으로 한 결과와 비교하여 유역 유사성 평가의 효용성을 확인하였다. 수문학적 거리산정을 위하여 영국의 FEH(Flood Estimation Handbook)에서 제안하는 유클라디안 거리법을 적용하였으며, 유황관련계수의 군집화를 위하여 SPSS프로그램을 사용하여 계층적 군집분석의 Ward법을 적용하였다. 유역 그룹화를 수행한 결과 유역특성인자를 반영한 수문학적 거리(유사성 척도)에 의한 그룹은 총 3개(H1, H2, H3)이며, 유황관련계수에 의한 그룹은 총 4개(F1, F2, F3, F4)로 분류되었다. 두 그룹들을 대응하여 비교분석한 결과 H1그룹의 7개 유역 중 6개 유역과 H3의 모든 유역이 F1그룹과 대응하였고 H2그룹의 5개 유역 중 4개 유역이 F2그룹과 대응하였으므로 본 연구의 유사성 척도에 의한 유역 그룹화가 효용성이 있음을 확인하였다.

• 한국조경학회지
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• 제19권3호
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• pp.98-127
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• 1991

This study has purposes of not only establishing urban community park systems and index for designing the parks, which were reviewed from Korean urban community parks, but also finding the relation and the enticing area according to the catchment of urban community parks. This paper suggested two hypotheses. a. The strength of the catchment force of urban community parks can be represented to the usetimes or visitors of the parks, related with the distance for reaching the parks. b. The strength of the catchment force of the parks can be found to express the idiosyncratic one according to the qualitative differences between the parks. The suggested hypotheses were testified from Korean 9 urban community parks in Seoul., Suwon, Chongju, and Chonan, conforming the multiregressions of the variables, distance and usetime in the case of the first hypothesis, scale, the ratio of green space, population, the budget for the park, facilities and the function of the city in the case of the second hypothesis. All the correlation coefficients of usetime with distance except one were over about 0.8. The second hypothesis was testified with multiregressions for the variables. Therefore, the enticing area could be divided into three zones ; a closed aone to parks, a good used aone for parks, a possible zone for using parks.

• 한국농공학회지
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• 제15권3호
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• pp.3096-3106
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• 1973

As a link in the chain of antidrought measure, our attempt is made to obtain basic informations on the construction of an infiltration gallary which can be supplied with irrigation water by catching of underground water in small river beds, which is economical, permanent and efficient. The experiment was made, concerning the structure of catchment conduits, by constructing a model sand tank $1.5m{\times}5m{\times}1.5m$ in dimension made of reinforced concrete. Various kinds of measuring equipment were attached to the model tank which contains a set of catchment conduits, each of them was made 30cm in diameter and 60cm in length with the ratio of sectional area to total area of influx holes 10:1, 20:1, 30:1. The average size of influx holes was fixed from 0mm to 10mm, 20mm and 30mm in diameter respectively. Obtained results are as follow; (a) In view of the water catchment capacity, manufacturing cost and the antipressure strength of the catchment conduits, it is the best method to decide the total number of influx holes 20 per sq. meter of each tile surface, and the size of influx holes 20mm in diameter, when the conduits have diameter less than 1m. (b) The greatest factor of safety against external load is to arrange the influx holes in a zigzag manner on the tile surface. The most effective formula of arrangement is $S{\geqq}\sqrt{2gd}$ where: s : spacing of opening row. g : spacing of opening line. d : diameter of influs hole.

• 한국환경과학회지
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• 제10권3호
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• pp.217-223
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• 2001

Where no records are available at a site, a preliminary estimate may be made from relations between floods and catchment chatacteristics. A number of these chatacteristics were chosen for testing and were measured for those catchments where mean annual flood estimates were available. Although the improvement using extended data in regression of flood estimates on catchment characteristics was small, this may be due to the limitations of the regression model. When an individual short term record is to be extended, more detailed attention can be given; an example is presented of the technique which should be adopted in practice, particularly when a short term record covers a period which is known to be biassed. A method of extending the peaks over a threshold series is presented with a numerical example. The extension of records directly from rainfall by means of a conceptual model is discussed, although the application of such methods is likely to be limited by lack of recording raingauge information. Methods of combining information from various sources are discussed in terms of information from catchment characteristics supplemented by records. but are generally applicable to different sources of information. The application of this technique to estimating the probable maximum flood requires more conservative assumptions about the antecedent condition, storm profile and unit hydrograph. It is suggested that the profile and catchment wetness index at the start of the design duration should be based on the assumption that the estimated maximum rainfall occurs in all durations centered on the storm peak.

• Water Engineering Research
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• 제6권2호
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• pp.91-99
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• 2005

One of the most important factors for estimating a flood runoff from streams is the lag time. It is well known that the lag time is affected by the morphometric properties of basin which can be expressed by catchment shape descriptors. In this paper, the notion of the geometric characteristics of an equivalent ellipse proposed by Moussa(2003) was applied for calculating the lag time of geomorphologic instantaneous unit hydrograph(GIUH) at a basin outlet. The lag time was obtained from the observed data of rainfall and runoff by using the method of moments and the procedure based on geomorphology was used for GIUH. The relationships between the basin morphometric properties and the hydrological response were discussed based on application to 3 catchments in Korea. Additionally, the shapes of equivalent ellipse were examined how they are transformed from upstream area to downstream one. As a result, the relationship between the lag time and descriptors was shown to be close, and the shape of ellipse was presented to approach a circle along the river downwards. These results may be expanded to the estimation of hydrological response of ungauged catchment.

• 한국물환경학회지
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• 제22권5호
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• pp.815-823
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• 2006

The hydrologic cycle in urban catchment has been changed due to the expansion of impervious area by rapid urban development. In this study, the SWMM 5 (Storm Water Management Model 5) model was used to simulate the hydrologic cycle of the Dorimcheon catchment which suffers from the distorted hydrologic cycle as a typical urban catchment. This study compare continuous simulation of urban runoff combining the channel and sewer system with that of channel only in the Dorimcheon catchment. Continuous simulations of urban runoff were performed for the upstream basin of Dorim bridge. The urban impervious regions were processed by the land use analysis from LANDSAT_TM images. It was performed from 1975 to 2000 for every five years. Surface, groundwater and wastewater runoffs were additionally included in the simulations one at a time. Such simulations made it possible to evaluate those components quantitatively. The result of continuous simulation of urban runoff combining the channel and sewer system is that peak flow and recession are well simulated. The analysis results of urbanization effect on runoff are as follows: the surface runoff in 2000 increases to 64% of the whole precipitation whereas the surface runoff in 1975 amounts to 46% of the precipitation; the groundwater runoff in 2000 amounts to 6% and shows 8% decrease during the period from 1975 to 2000.

• 한국제4기학회지
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• 제19권1호
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• pp.41-46
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• 2005

This study discusses the soil erosion on hillslopes and sediment deposition in lakes within catchments in South Korea. In order to determine seasonal variations of sedimentation in Yeongcheon and Seondong lakes, the sediment traps were set in the deep part of both lakes and lake sediments have been sampledmonthly from July 2004 to August 2005. Some properties such as highmineral content, fine particle size and high particle density in the Yeongcheon Lake indicate intensive soil erosion, sediment transportation and deposition throughout the catchment for a long time. The high sediment yield in the Seondong Lake is related with higher weathering intensity and extreme soil erosion by running water due to higher seasonal rainfall amount. Rates of erosion and sedimentation in the Seondong Lake are estimated to be higher than those of the Yeongcheon Lake, suggesting that the Seondong Lake is associated with higher precipitation, smaller catchment area, and extreme soil vulnerability to ephemeral erosion by overland flow during the heavy rainfall event. Consequently, both catchments are characterized by different erosion and sedimentation processes, as well as different geomorphic factors (bedrock, soil structure, rainfall intensity and catchment area).

• 한국물환경학회지
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• 제29권6호
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• pp.730-738
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• 2013

In recent years, low impact development (LID) has emerged as an effective approach to control stormwater in an urban area, and watershed and stormwater managers need modeling tools to evaluate alternative plans for controlling stormwater. This study illustrates how to design and evaluate the effect of non-point pollutant management using SUSTAIN which is developed by USEPA. SUSTAIN can provide evaluating, selecting, and placing LID facilities in an urban catchment based on user-defined cost-effectiveness criteria. Also, this paper suggests a minimal methodology for estimating model parameters for modeling an ungauged urban catchment to reflect the situation of typical Korean urban interested catchments which are usually ungauged. In addition, the optimal length of various LID facilities and the optimal number of units in our test catchment are estimated.