• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.976-976
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• 2012

The applicability of a distributed rainfall-runoff model for large river basin flood forecasts is analyzed by applying the model to the Nakdong River basin. The spatially explicit hydrologic model was constructed and calibrated by the several storm events. The assimilation of the large scale Nakdong River basin were conducted by calibrating the sub-basin channel outflow, dam discharge in the basin rainfall-runoff model. The applicability of automatic and semi-automatic calibration methods was analyzed for real time calibrations. Further an ensemble distributed rainfall runoff model has been developed to measure the runoff hydrograph generated for any temporally-spatially varied rainfall events, also the runoff of basin can be forecast at any location as well. The results of distributed rainfall-runoff model are very useful for flood managements on the large scale basins. That offer facile, realistic management method for the avoiding the potential flooding impacts and provide a reference for the construct and developing of flood control facilities.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.204-208
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• 2006

This study is to develop a distributed urban flood runoff model that simulates the road runoff and to test the applicability of the model by applying to Pyeongtaek city of $12.2km^2$. To generate the runoff along the runoff, agree burned DEM (Digital Elevation Model) with road networks was suggested and the proper spatial resolution of DEM was identified finer than 15 m. To test the model applicability, 32 points on the road networks were selected and the hydrographs of each point were generated. The test showed reasonable results that increase the road runoff from the high elevation roads to the low elevation roads and the road runoff considering rainwater drainage from the road also showed reasonable results.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.2215-2219
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• 2009

For model calibration in rainfall-runoff modeling, streamflow data at a specific outlet is obviously required but is not sufficient to identify parameters of a model since numerous parameter combinations can result in very similar model performance measures (i.e. objective functions) and indistinguishable simulated hydrographs. This phenomenon has been called 'equifinality' due to inherent parameter uncertainty involved in rainfall-runoff modeling. This study aims to investigate catchment responses in time and space to various uncertain parameter sets in distributed rainfall-runoff modeling. Seven plausible (or behavioral) parameter sets, which guarantee identically-good model performances, were sampled using deterministic and stochastic optimization methods entitled SCE and SCEM, respectively. Then, we applied them to a computational tracer method linked with a distributed rainfall-runoff model in order to trace and visualize potential origins of streamflow at a catchment outlet. The results showed that all hydrograph simulations based on the plausible parameter sets were performed equally well while internal catchment responses to them showed totally different aspects; different parameter values led to different distributions with respect to the streamflow origins in space and time despite identical simulated hydrographs. Additional information provided by the computational tracer method may be utilized as a complementary constraint for filtering out non-physical parameter set(s) (or reducing parameter uncertainty) in distributed rainfall-runoff modeling.

• 한국습지학회지
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• 제14권3호
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• pp.385-397
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• 2012

격자 기반의 물리적 분포형 모형은 유역의 물리적 매개변수와 격자 형식의 공간 및 수문자료를 이용해서 유출해석을 수행한다. 본 연구에서는 격자 기반의 물리적 분포형 강우-유출 모형인 GRM(Grid based Rainfall-runoff Model)의 실시간 유출해석 모듈인 GRM RT(Real Time)를 이용해서 실시간 유출해석 시스템을 개발하였다. 실시간으로 수신되는 기상레이더 자료를 기상청의 실시간 AWS 자료를 이용하여 보정한 후 유출해석에 적용하며, 수위관측소 자료로부터 생성되는 유량자료를 이용해서 유출모형을 실시간 보정한다. 본 연구에서는 실시간 유출해석 시스템 구축을 위해서 필요한 데이터베이스를 설계 및 구현하였으며, 분포형 모형과 레이더 자료를 이용한 실시간 유출해석 절차를 정립하였다. 또한 개발된 시스템의 성능을 평가하고 실시간 모형보정에 대한 적용성을 평가하였다. 소양강댐 상류에 위치한 내린천 수위관측소 유역을 대상으로 실시간 유출해석 시스템을 적용하고 그 결과를 평가하였다.

• 물과 미래
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• 제29권6호
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• pp.131-139
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• 1996

본 연구의 목적은 분포형 강우-유출 모형에 의한 유출량을 해석하는 것이다. 본 모형은 두개의 부모형으로 구성되어 있다. 하나는 수계망(drainage network) 을 통하여 운동파 모형(kinematic wave model)을 이용하여 분포적으로 추적되는 직접 유출 부모형이며, 다른 하나는 기저유출 부모형으로서 집중형으로 취급되어 유역 출구에서만 계산하도록 하였다. 본 연구에서 개발된 모형에 의하여 청미천 유역에 대한 유출량의 시간적, 공간적인 분포를 고려할 수 있었다.

• 한국환경과학회지
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• 제20권1호
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• pp.93-106
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• 2011

Physically-based resampling scheme for roughness coefficient of surface runoff considering the spatial landuse distribution was suggested for the purpose of effective operational application of recent grid-based distributed rainfall runoff model. Generally grid scale(mother scale) of hydrologic modeling can be greater than the scale (child scale) of original GIS thematic digital map when the objective basin is wide or topographically simple, so the modeler uses large grid scale. The resampled roughness coefficient was estimated and compared using 3 different schemes of Predominant, Composite and Mosaic approaches and total runoff volume and peak streamflow were computed through distributed rainfall-runoff model. For quantitative assessment of biases between computational simulation and observation, runoff responses for the roughness estimated using the 3 different schemes were evaluated using MAPE(Mean Areal Percentage Error), RMSE(Root-Mean Squared Error), and COE(Coefficient of Efficiency). As a result, in the case of 500m scale Mosaic resampling for the natural and urban basin, the distribution of surface runoff roughness coefficient shows biggest difference from that of original scale but surface runoff simulation shows smallest, especially in peakflow rather than total runoff volume.

• 한국농공학회논문집
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• 제52권4호
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• pp.1-10
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• 2010

In this study, two estimation equations for preparing stream data for distributed storm runoff model were developed by analyzing the nonlinear relation between upstream flow-length and stream width, and between upstream flow-length and stream bed-slope. The equations for stream cell were tested in Chungjudam watershed (6,661 $km^2$) using KIMSTORM. Six storm events occurring between 2003 and 2008 were selected for the model calibration and verification before the test of equations. The average values of the Nash-Sutcliffe model efficiency (ME), the volume conservation index (VCI), the relative error of peak runoff rate (EQp), and the difference of time to peak runoff (DTp) were 0.929, 1.035, 0.037, and -0.406 hr for the calibrated four storm events and 0.956, 0.939, 0.055, and 0.729 hr for the two verified storm events respectively. The estimation equations were tested to the storm events, and compared the flood hydrograph. The test result showed that the estimation equation of stream width reduced the peak runoff and delaying the time to peak runoff, and the estimation equation of stream bed-slope showed the opposite results.

• 한국농공학회논문집
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• 제60권1호
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• pp.111-120
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• 2018

The purpose of this study was to develop a ridge regression (RR) model to estimate BOD and TP load using runoff weighted value. The concept of runoff weighted value, based on distributed curve-number (CN), was introduced to reflect the impact of land covers on runoff. The estimated runoff depths by distributed CN were closer to the observed values than those by area weighted mean CN. The RR is a technique used when the data suffers from multicollinearity. The RR model was developed for five flow duration intervals with the independent variables of daily runoff discharge of seven land covers and dependent variables of daily pollutant load. The RR model was applied to Heuk river watershed, a subwatershed of the Han river watershed. The variance inflation factors of the RR model decreased to the value less than 10. The RR model showed a good performance with Nash-Sutcliffe efficiency (NSE) of 0.73 and 0.87, and Pearson correlation coefficient of 0.88 and 0.93 for BOD and TP, respectively. The results suggest that the methods used in the study can be applied to estimate pollutant load of different land cover watersheds using limited data.

• 한국수자원학회논문집
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• 제42권3호
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• pp.247-257
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• 2009

본 연구에서는 다방향 흐름 분배 알고리듬과 실시간 보정 알고리듬을 개발하여 분포형 강우-유출 모형에 적용하였다. 개발된 알고리듬의 적용과 분포형 모형 적용상의 약점인 계산시간 개선을 위해 비교적 간단한 수문과정 지배 방정식들을 이용하여 분포형 강우-유출 모형을 작성하였다. DEM(Digital Elevation Model)를 이용하여 공간해상도 변화에 따른 지형정보와 흐름정보의 변동성을 파악하였다. 모의수행 전처리 과정으로 가용한 고해상도 DEM 자료를 사용하여 공간해상도 변화에 따른 흐름정보의 손실을 최소화하고 상세흐름정보를 저해상도 흐름정보에 반영시키는 다방향 흐름분배 알고리듬을 개발하였다. 또한 실시간으로 유역상태량을 보정하는 실시간 보정 알고리듬을 개발하다. 개발된 모형은 저해상도 모의에서 유출 과정의 실제적 거동 정보를 유지할 수 있다. 그러므로 예측 정확도 향상 및 계산시간의 개선이 기대된다.

• 한국수자원학회논문집
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• 제33권S1호
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• pp.28-36
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• 2000

A TIN, Triagulated Irregular Network, based topographic modeling method and a distributed rainfall-runoff model using the topographic representation is presented. In the TIN based topographic representation, a watershed basin is modeled as a set of contiguous non-overlapping triagular facets : the watershed basin is subdivided according to streamlines to deal with water movement one-dimensionally ; and each partitioned catchment is approximated to a slope element having a quasi-three-dimensional shape by using cubic spline functions. On an approximated slope element, water movement is represented by combined surface-subsurface kinematic wave equations considering a change of slope gradient and slope width. By using the distributed rainfall-runoff model, the effects of spatial variability of soil properties on runoff response are examined.