• 한국농공학회논문집
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• 제54권4호
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• pp.1-8
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• 2012

This study is to assess the reduction of non-point source pollution loads for rice straw surface covering of upland crop cultivation at a watershed scale. For Byulmi-cheon watershed ($1.21km^2$) located in the upstream of Gyeongancheon, the HSPF (Hydrological Simulation Program-Fortran), a physically based distributed hydrological model was applied. Before evaluation, the model was calibrated and validated using 9 rainfall events. The Nash-Sutcliffe model efficiency (NSE) for streamflow was 0.62~0.78 and the NSE for water quality (Sediment, T-N, and T-P) were 0.68, 0.60, and 0.58 respectively. From the field experiment of 16 rainfall events, the rice straw covering reduced surface runoff average 10 % compared to normal surface condition. By handling infiltration parameter (INFILT) in the model, the value of 16.0 mm/hr was found to reduce about 10 % reduction of surface runoff. For this condition, the reduction effect of Sediment, T-N, and T-P loads were 87.2, 28.5, and 85.1 % respectively. The rice straw surface covering was effective for removing surface runoff dependent loads such as Sediment and T-P.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제25권4호
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• pp.462-470
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• 2012

The availability and efficient use of the feed resources in India are the primary drivers to maximize productivity of Indian livestock. Feed security is vital to the livestock management, extent of use, conservation and productivity enhancement. Assessment and forecasting of livestock feed resources are most important for effective planning and policy making. In the present study, 40 years of data on crop production, land use pattern, rainfall, its deviation from normal, area under crop and yield of crop were collected and modeled to forecast the likely production of feed resources for the next 20 years. The higher order auto-regressive (AR) models were used to develop efficient forecasting models. Use of climatic variables (actual rainfall and its deviation from normal) in combination with non-climatic factors like area under each crop, yield of crop, lag period etc., increased the efficiency of forecasting models. From the best fitting models, the current total dry matter (DM) availability in India was estimated to be 510.6 million tonnes (mt) comprising of 47.2 mt from concentrates, 319.6 mt from crop residues and 143.8 mt from greens. The availability of DM from dry fodder, green fodder and concentrates is forecasted at 409.4, 135.6 and 61.2 mt, respectively, for 2030.

• 한국수자원학회논문집
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• 제31권6호
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• pp.741-755
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• 1998

인공배수 되고 있는 농업유역을 위한 확장된 TOPMODEL은 강우유출 모의를 위해 개발되어졌다. 불포화흐름의 해석을 위해 기존 모형의 저류함수법과 본 연구에서 새로이 제시하는 전달함수법을 비교하였다. 매개변수의 민감도 결정과 저류함수법과 전달함수법간의 거동의 비교를 위하여 영역화 민감도 분석기법이 쓰였다. Monte-Carlo 방법을 활용한 변수 추정시, 전달함수를 활용한 모의가 보다 많은 성공적인 모의결과의 변수조합이 관찰되었다. 강우유출 양상의 계절적 변동을 고려하기 위해 일곱 개의 강우사상이 만감도 분석에 활용되었다.

• 한국물환경학회지
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• 제24권5호
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• pp.611-617
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• 2008

It is necessary to analysis the data characteristics of discharge and water quality for efficient water resources management, aggressive alternatives to inundation by flood and various water pollution accidents, the basic information to manage water quality in lakes and to make environmental policy. Therefore, the present study applied Self-Organizing Map (SOM) showing excellent performance in classifying patterns with weights estimated by self-organization. The result revealed five patterns and TOC versus rainfall-storage data according to the respective patterns were depicted in two-dimensional plots. The visualization presented better understanding of data distribution pattern. The result in the present study might be expected to contribute to the modeling procedure for data prediction in the future.

• 한국농공학회논문집
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• 제54권5호
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• pp.129-139
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• 2012

Accurate modeling rainfall induced landslide and slope stability requires a detailed knowledge of the distribution of material strength characteristics and suction distribution. However, material properties obtained from the drying cycle are still used for infiltration analysis in many cases, even though material properties of wetting cycle are quite different from those of drying cycle due to hydraulic hysteresis and air occlusion. Therefore, the selection of proper material properties such as soil-water retention curve (SWRC) and the hydraulic conductivity function (HCF) reflecting characteristics of wetting cycle and air occlusion is an essential prerequisite in order to simulate the infiltration phenomena and to predict the suction and water content distribution in unsaturated soils. It is concluded that the simulation of infiltration with material properties from the drying cycle did not reasonably match with experimental outputs. Further discussion is made on how to describe the material properties considering air occlusion during wetting cycle over the entire suction range in order to simulate infiltration phenomena.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2020년도 학술발표회
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• pp.122-122
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• 2020

Urban flood simulation plays a vital role in national flood early warning, prevention and mitigation. In recent studies on 2-dimensional flood modeling, the integrated run-off inundation model is gaining grounds due to its ability to perform in greater computational efficiency. The adaptive quadtree shallow water numerical technique used in this model implements the adaptive mesh refinement (AMR) in this simulation, a procedure in which the grid resolution is refined automatically following the flood flow. The method discounts the necessity to create a whole domain mesh over a complex catchment area, which is one of the most time-consuming steps in flood simulation. This research applies the dynamic grid refinement method in simulating the recent extreme flood events in Metro Manila, Philippines. The rainfall events utilized were during Typhoon Ketsana 2009, and Southwest monsoon surges in 2012 and 2013. In order to much more visualize the urban flooding that incorporates the flow within buildings and high-elevation areas, Digital Surface Model (DSM) resolution of 5m was used in representing the ground elevation. Results were calibrated through the flood point validation data and compared to the present flood hazard maps used for policy making by the national government agency. The accuracy and efficiency of the method provides a strong front in making it commendable to use for early warning and flood inundation analysis for future similar flood events.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.142-142
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• 2021

An arbitrary representation of an urban drainage sewer system was devised using a geographic information system (GIS) tool in order to calculate the surface and subsurface flow interaction for simulating urban flood. The proposed methodology is a mean to supplement the unavailability of systematized drainage system using high-resolution digital elevation(DEM) data in under-developed countries. A modified DEM was also developed to represent the flood propagation through buildings and road system from digital surface models (DSM) and barely visible streams in digital terrain models (DTM). The manhole, sewer pipe and storm drain parameters are obtained through field validation and followed the guidelines from the Plumbing law of the Philippines. The flow discharge from surface to the devised sewer pipes through the storm drains are calculated. The resulting flood simulation using the modified DEM was validated using the observed flood inundation during a rainfall event. The proposed methodology for constructing a hypothetical drainage system allows parameter adjustments such as size, elevation, location, slope, etc. which permits the flood depth prediction for variable factors the Plumbing law. The research can therefore be employed to simulate urban flood forecasts that can be utilized from traffic advisories to early warning procedures during extreme rainfall events.

• 한국수자원학회논문집
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• 제37권4호
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• pp.341-352
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• 2004

본 연구(II)에서는 앞선 연구(I)에서 개발된 모형의 적용성을 증명하기 위해 2가지 등경사 가상유역에 대해 적용하였다. 먼저, 불투수조건의 1차원 흐름 추적에 대해 적용하고, 두 번째로 원추모양의 일부분처럼 되어있는 V자형 불투수 가상유역에 2차원 흐름추적을 적용하였다. 각자의 경우에서 모형의 결과와 관측치는 잘 일치하였다. 또한, 본 도형을 8$\textrm{km}^2$의 유역면적을 가지는 설마천 유역과 33.2$\textrm{km}^2$의 유역면적을 가지는 동곡 유역에 각각 적용하였고, 모의된 결과는 관측치와 잘 일치하는 것으로 나타났다. Monte Carlo 모의 역시 같은 유역에 적용하여 평가하였다. 본 모형은 향후 실시간 강우-유출해석 및 예보에 적극 사용될 수 있으며 유역단위 홍수조절에도 큰 기여를 할 수 있을 것으로 사료되었다.

• 한국경제지리학회지
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• 제16권2호
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• pp.262-274
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• 2013

최근 도시에 발생하는 폭우 폭설 등의 극단적인 기상현상은 대규모 재난으로 이어지며 사회적인 문제가 되고 있다. 본 연구는 극단적인 강수현상 발생 시 통행효율성을 증대시켜 도시 지역 내 경제적 손실을 최소화할 수 있는 최적의 침수 정보 전달 시나리오를 선정하고자 한다. 이를 위해 서울시 서초구 서초동 일대를 사례지역으로 NetLogo 툴킷을 활용한 모델을 작성하여, 극단적인 강수 발생 시 정보전달 시나리오별 통행시간의 시뮬레이션을 수행하였다. 시뮬레이션에 따르면, 노면에 습기가 있거나 강설량 20mm 미만인 시나리오에서는 20~40%의 운전자에게, 강설량 20mm 이상의 폭우가 발생한 시나리오에서는 40~60%의 운전자에게 도로통제의 정보를 전달하는 것이 효과적이라는 결과가 각각 도출되었다.