• Korean Journal of Hydrosciences
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• 제1권
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• pp.1-14
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• 1990

The analytical diffusion model is first formulated and its characteristics are critically reviewed. The flood events during the 1985-1986 flood seasons in the IHP Pyungchang Representative Basin are routed by this model and are compared with those routed by the kinematic wave model. The present model is proven to be an excellent means of taking the backwater effects due to lateral inflow or downstream river stage variations into consideration in channel routing of flood flows. It also requires much less effort and computing time at a desired station compared to any other reliable flood routing methods.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.637-640
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• 2008

Flood control and river improvement works are carried out every year for the defense of the flood disaster, it is impossible to avoid the damage when there is a flood exceeding the capacity of hydraulic structures. Therefore, nonstructural counter plans such as the establishment of flood hazard maps, the flood warning systems are essential with structural counter plans. In this study, analysis of the internal inundation effect using rainfall runoff model such as PC-SWMM was applied to Woo Ee experimental stream basin. Also, the design frequency analysis for effects of the external inundation was accomplished by main parameter estimation for conclusive hydraulic routing using HEC-RAS model. Finally, inundated areas for flood hazard map were estimated at Woo Ee downstream basin according to flood frequency using HEC-GeoRAS model linked by Arc View GIS.

• Water Engineering Research
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• 제3권4호
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• pp.215-234
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• 2002

Uncertainty in dam breach flood routing results was analyzed in order to provide the basis fer the investigation of their effects on the flood damage assessments and dam safety risk assessments. The Monte Carlo simulation based on Latin Hypercube Sampling technique was used to generate random values for two uncertain input parameters (i.e., dam breach parameters and Manning's n roughness coefficients) of a dam breach flood routing analysis model. The flood routing results without considering the uncertainty in two input parameters were compared with those with considering the uncertainty. This paper showed that dam breach flood routing results heavily depend on the two uncertain input parameters. This study indicated that the flood damage assessments in the downstream areas can be critical if uncertainty in dam breach flood routing results are considered in a reasonable manner.

• 한국수자원학회논문집
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• 제38권9호
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• pp.747-760
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• 2005

본 연구에서는 한강수계를 대상으로 1차원 동역학적 홍수추적모형인 DAMBRK 모형을 이용하여 상류댐 및 중간댐의 영향을 고려한 홍수추적을 실시하였다. 또한 중간댐에서의 홍수추적기법의 타당성을 검토하기 위해서 다양한 형태의 가상의 저수지에 대한 dynamic routing과 storage routing에서의 유출량을 검토하였다. 모형의 적용성을 검증하기 위해서 1990년 9월 및 1995년 8월 홍수사상에 대한 홍수추적을 실시하여 실측값과 비교${\cdot}$검토하였다. 한강수계에 극한홍수사상과 각 하천의 설계홍수량을 적용하여 중간댐들의 영향을 고려한 홍수추적을 수행하여 그 결과를 도시하였다. 본 연구를 통해서 향후 한강유역에서의 홍수예경보와 효율적인 홍수조절을 통한 홍수정보시스템 확립에 크게 기여할 것으로 판단된다.

• 물과 미래
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• 제23권3호
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• pp.385-395
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• 1990

측방유입수가 고려되는 3변수 Muskingum하도추적모형을 낙동강 수계중 왜관에서 적포교구간의 12개 홍수사상에 대하여 적용하였고, 기존 방법인 2변수 Muskingum방법의 저류상수 K와 가중계수 x에 추가된 α는 측방유입수를 고려해주는 변수이다. 3변수모형의 추적방정식은 유한차분방정식으로 표현되며, 추적상수 결정은 Matrix Inversion에 의하여 직접 계산 가능하며, 이로부터 각 홍수사상의 K x 값을 구할 수 있다. 본 연구를 실유역에 적용하여 실측치와 비교하여본 결과 비교적 잘 맞음을 알 수 있어쓰ㅇ며 K와 x값은 하도특성인자로서 홍수규모와 관계되고 측방유입인자 α는 강우 특성에 의하여 지배되는 변수로 판단되었으며 α값은 측방유입량이 클수록 값이 커지는 성향으로 나타났다.

• 물과 미래
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• 제27권1호
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• pp.89-99
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• 1994

현재까지 국내의 홍수예측업무는 과거에 수집된 자료집단을 이용한 변수추정에 의하여 시행되고 있으나, 최근 여러 가지 순환추정 알고리즘을 적용한 홍수예측 또는 변수추정에 관한 많은 연구가 이루어지고 있다. 본 논문은 실시간 홍수예측 및 변수추정에 관한 연구로서, 특히 강우-유출모형의 상태 및 매개변수의 동시추정에 관한 추계학적 현상을 고려하였다. 홍수예측에 관한 시스템은 $\phi$ 지수에 의한 유효강우의 산정과 지체효과를 고려한 n개의 비선형 저수지모형에 의한 홍수축적으로 구성하였다. 그리고 변수추정모형과 홍수추적 모형을 상호연계하여 변수를 포함하는 확대 상태-공간모형으로 상태 및 매개변수의 동시추정에 관한 시스템을 구성하였다. 상태-공간모형에 대한 상태 및 변수추정기법으로 GLS 추정과 MAP 추정에 대하여 비교 검토하였다. 모형의 식별을 위한 민감도 분석은 추정변수의 공분산 행렬을 사용하였다.

• Korean Journal of Hydrosciences
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• 제4권
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• pp.11-19
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• 1993

The peak flood discharge at a downstream station and the flood travel time between a pair of dams due to a specific flood release from the upper reservoir are computed using a hydraulic river channel routing method. The study covered the whole large reservoir system in the Han River, Korea. The computed flood discharges and the travel times between dams were correlated with the duration and the magnitude of flood release rate at the upstream reservoir, and hence a multiple regression model is proposed for each river reach between a pair of dams. The peak flood discharge at a downstream location can be converted to the peak flood stage by a rating curve. Hence, the proposed regression model could be used to forecast the peak flood stage at a downstream location and the flood travel time between dams using the information on the flood travel time, release rate and duration from the upper dam.

• Water Engineering Research
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• 제2권2호
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• pp.113-121
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• 2001

The objective of this study is to develop a prediction mode for a flood forecasting system in the downstream of the Nakdong river basin. Ranging from the gauging station at Jindong to the Nakdong estuary barrage, the hydraulic flood routing model(DWOPER) based on the Saint Venant equation was calibrated by comparing the calculated river stage with the observed river stages using four different flood events recorded. The upstream boundary condition was specified by the measured river stage data at Jindong station and the downstream boundary condition was given according to the tide level data observed at he Nakdong estuary barrage. The lateral inflow from tributaries were estimated by the rainfall-runoff model. In the calibration process, the optimum roughness coefficients for proper functions of channel reach and discharge were determined by minimizing the sum of the differences between the observed and the computed stage. In addition, the forecasting lead time on the basis of each gauging station was determined by a numerical simulation technique. Also, we suggested a model structure for a real-time flood forecasting system and tested it on the basis of past flood events. The testing results of the developed system showed close agreement between the forecasted and observed stages. Therefore, it is expected that the flood forecasting system we developed can improve the accuracy of flood forecasting on the Nakdong river.

• 물과 미래
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• 제22권4호
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• pp.453-461
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• 1989

해석적 확산 모델의 지배방정식의 유도와 해를 구성하는 각 항의 특성에 관해 상세하게 살펴본후 IHP 평창강 대표유역의 1985-1986 홍수사상을 본 모델로 추적하여 Kinematic Wave 모델에 의한 결과와 비교하였다. 결과분석에 의하면 해석적 확산 모델에 의한 해는 Kinematic Wave 모델에 의한 해보다 실측치에 훨씬 가까운 결과를 주는 것으로 나타났으며 본 모델은 특히 측방류입수나 하류수위변동에 의한 배수효과까지 고려하여 홍수를 추적할 수 있어 타 간략해법보다 정확한 결과를 줄 수 있음이 입증되었다. 또한 이 모델은 원하는 특정 하천단면에서의 유출수문곡선을 계산할 수 있어 전산시간과 소요자료 정리에 필요한 노력을 크게 줄일 수 있다.

• Korean Journal of Hydrosciences
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• 제2권
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• pp.69-84
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• 1991

US NWS/NETWORK is applied for the analysis of the flood of July 11-15, 1981 through the Goan-Indogyo reach of the Han River. For the flood hydrography synthesis of the lateral inflows from the major tributaries into the main reach the Cleak method is employed. NETWORK coupled with the Clark method of hydrography synthesis simulated with a fair accuracy the oberved flood hydrograph at the downstream boundary of the routing reach. The dffect of SCS runoff curve number for fributary flood synthesis is evaluated. The characteristics of the station variations and time variations of the flood discharges in the reach is also analyzed.