• 한국수자원학회논문집
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• 제38권9호
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• pp.713-725
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• 2005

본 연구에서는 미국 지질조사국에서 개발한 PRMS 모형을 국내 7개 댐유역에 적용하여 국내 적용성과 모의한 계를 분석하였다. 모형의 적용성을 평가하기 위해 모형 이론과 매개변수에 대해 검토하고, 국내 실정을 고려한 입력자료와 매개변수 추정의 가용성을 분석하였다. 각 적용유역들에서 GIS자료를 활용하여 추정 가능한 매개변수들은 추정하고 나머지 변수들은 Rosenbrock 방법을 이용하여 보정하였다. 모의결과를 다각적으로 분석하여 PRMS 모형의 모의 능력과 한계를 분석한 결과 PRMS 모형은 모든 적용유역에서 관측치에 높은 적합성을 나타내었다. 기본값을 사용한 융설모의에서도 비교적 정확한 모의가 가능한 것으로 나타났다. 적용 유역면적에 상관없이 신뢰성 높은 유출분석이 가능하였으나, 대유역인 경우 준분포형적인 특성보다는 일체형모형에 가까운 유출모의를 하는 것으로 나타났다.

• 물과 미래
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• 제35권5호
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• pp.31-43
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• 2002

본 연구에서는 온난화에 의한 하천유역의 수문응답(강우유출, 특히 일단위의 유황)의 변화양상을 수치실험을 통해 정량적으로 평가하였다. 이산화탄소 농도의 증가에 따른 온난화의 진행으로 야기되는 수문학적 평가는 많은 관측자료를 필요로 하며 이를 정량적으로 평가한다는 것은 대단히 어려운 일이다. 따라서 장래의 기후를 예측하는 수단으로서 적정한 시나리오를 상정하여 평하는 방법을 생각할 수 있다. 본 연구에서는 여러 가지 상정할 수 있는 시나리오 중 기온은 $0^{\circ}C$에서 $4.0^{\circ}C$까지 변화하며 강수량은 15%까지 증감할 수 있다는 시나리오를 상정하여 불확실성이 큰 지구온난화의 문제에 대하여 간단하면서 명확한 가정을 도입하였다. 따라서, 대상유역인 안동댐 유역에 대한 장래의 하천유량은 기후변화 시나리오에서 야기되는 강수량을 발생시켜 탱크모형에 의하여 일 유량을 모의 발생하게 된다. 본 연구에서는 2030년을 이산화탄소 농도가 배증되는 시점 ($2{\times}CO2$), 2010년, 2020년 및 2050년을 각각 ($1.5{\times}CO2$),($1.75{\times}CO2$) 및 ($2.5{\times}CO2$)로 설정하였으며, 이 시기에 대한 하천 유황의 해석 및 온난화가 발생되지 않았을 때와의 비교 검토를 실시하였다.

• 농업과학연구
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• 제46권4호
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• pp.769-779
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• 2019

Chilli peppers are predominantly cultivated in open field systems under abiotic and biotic stress conditions. Abiotic and biotic factors have a considerable effect on plant performance, fruit quantity, and quality. Chilli peppers grow well in a tropical climate due to their adaptation to warm and humid regions with temperatures ranging from 18 to 30℃. Nowadays, chilli peppers are cultivated all around the world under different climatic conditions, and their production is gradually expanding. Expected climate changes will likely cause huge and complex ecological consequences; high temperature, heavy rainfall, and drought have adverse effects on the vegetative and generative development of all agricultural crops including chilli peppers. To gain better insight into the effect of climate change, the growth, photosynthetic traits, morphological and physiological characteristics, yield, and fruit parameters of chilli peppers need to be studied under simulated climate change conditions. Moreover, it is important to develop alternative agrotechnologies to maintain the sustainability of pepper production. There are many conceivable ideas and concepts to sustain crop production under the extreme conditions of future climate change scenarios. Therefore, this review provides an overview of the adverse impacts of climate change and discusses how to find the best solutions to obtain a stable chilli pepper yield.

• 한국환경과학회지
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• 제20권9호
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• pp.1165-1182
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• 2011

The evaluation of potential submarine groundwater is an important research topic for exploring an alternative water resource. Two different approaches, water budget analysis and Rn mass balance method, were employed to investigate the annual variation of submarine groundwater discharge in 2010 at a marine watershed located at the south-eastern part of Korean Peninsula. In order to obtain reliable hydrological data during study period, temporal and spatial variations of rainfall and soil moisture had been collected and hydro-meterological data such as temperature, humidity and wind speed were collected The runoff response was simulated using SCS-CN method with spatial distributions of landuse and soil texture from GIS analysis. Six different methods were used to estimate the monthly variation of evapotranspiration and field measurements of soil moisture were used to account for the infiltration. Comparisons of infiltration and surface runoff between simulation and water balance with measurements showed coincidence. The water budget analysis and Rn mass balance method provide mean daily submarine groundwater as 5.35 and 4.07 $m^3/m/day$ in 2010, respectively.

• 한국기계가공학회지
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• 제19권4호
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• pp.58-64
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• 2020

Large-scale flooding due to extreme weather and typhoons causes heavy damage. This is especially true in urban areas where accumulated debris prevents the smooth drainage of rainwater in sewage facilities such as rain gutters installed near roads. In this study, to improve the drainage performance and effectively remove foreign substances by applying the dust screen used in rivers, the rain gutter with Coanda effect was simulated and compared with the experiment. The simulation was performed by setting the parameters to the fillet radius R₁ and R₂ at the top of the screen filter, the fillet radius R₃ at the bottom of the screen filter, and the height H of the gap W from the bottom. W is the gap at the backside of screen filter which is applied to stimulate the Coanda effect. According to the simulation results, the highest drain performance was 87.99% derived from R₁= 30mm, R₂= 5mm, R₃= 85mm, H= 75mm, and W= 2mm. The error rate of simulation results refer to the 4.89%~7.36% compared to the experimental results. In the future, by considering the slope according to the installation environment, the simulation results can be applied to the actual roadside to help prevent flood damage.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.485-488
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• 2007

Riverbank filtration is a kind of artificial aquifer recharge for the fresh water supply. By construction of several production wells penetrating the riverbank, surface water withdrawn from the river would pass riverbed. This extracted water is well known to be cooler than surface water in summer and warmer than surface water in winter, showing more constant water temperature. This characteristic of extracted water is applied to geothermal energy utilization. Prediction of the annual temperature variation of filtrated water is the major concern in this study. In Daesan-myeon, Changwon-si, Gyeongsangnam-do, South Korea, riverbank filtration facility has been on its operation for municipal water supply and thermal energy utilization since 2006. Appropriate hydraulic and thermal properties were estimated for flow and heat transfer modeling with given pumping rate and location. With the calibrated material properties and boundary conditions, we numerically reproduced measured head and temperature variation with acceptable error range. In the numerical simulation, the change of saturation ratio and river stage caused by rainfall was calculated and the resulting variation of thermal capacity and thermal conductivity was considered. Simulated temperature profiles can be used to assess the possible efficiency of geothermal energy utilization using riverbank filtration facility. Influence of pumping rate, pumping location on the extracted water temperature will be studied.

• 한국물환경학회지
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• 제22권4호
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• pp.648-657
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• 2006

Characteristics of water quantity and quality of the Anyangcheon were analyzed through many field measurements and the distributed hydrologic simulation model, Soil and Water Assessment Tool (SWAT). Event mean concentrations (EMCs) and baseflow mean concentrations were calculated from the data and the daily runoff were simulated by SWAT. The runoff was divided into the direct runoff and the baseflow. Using those values and quantity and quality data of release from the wastewater treatment plant (WWPT), unit loads of BOD, COD, SS, $NO_2-N$, $NO_3-N$, $NH_3-N$, and Dis-P were derived. EMCs of BOD and SS were even higher than the baseflow mean concentrations. The total runoff from October to April (7 months) of 2004 was just 13.5%, since the rainfall usually is concentrated in summer season. Futhermore BOD and SS were loaded during the event by 50.9% and 70.9%, respectively and over three quarters of total COD, $NO_2-N$, $NO_3-N$, $NH_3-N$, and Dis-P were flowed into the Anyangcheon during the remaining period. Therefore, the efficiency of WWPT for COD, $NO_2-N$, $NO_3-N$, $NH_3-N$, and Dis-P should be intensified from Oct. to Apr. and the runoff quality management of BOD and SS should be planned during the summer season.

• 한국수자원학회논문집
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• 제44권12호
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• pp.967-974
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• 2011

RDAPS 수치예보로부터 생산된 일단위 강우시계열을 바탕으로 유량 예측을 모의하고, 정성적인 중장기 예보를 고려한 ESP 분석을 수행하여 결과를 비교하고 적용성을 검토하였다. 금강유역을 대상으로 ESP, 정성적 기상예보를 고려한 ESP, RDAPS 기상수치예보에의한유량예측결과를평균유출량과비교 분석을 통해각기법별 결과의 개선효과를 평가하였다. 예측 모의 결과 기상정보를 고려한 ESP 방법의 결과가상대적으로 양호한 것으로 분석되었다. 확률예측의 정확도를 평가하기 위한 불일치율(Discrepancy Ratio) 분석 결과에서도 같은 결과를 얻었다. RDAPS 수치예보의 경우 3시간 단위의 누적강수라는 특성이 감안된 시간분해능을 갖는 일단위 시나리오로 개선되거나 장기간 동안 지속적인 모의 평가가 이루어진다면 더욱 정밀한 유량예측을 모의 할 수 있을 것으로 예상된다.

• 한국습지학회지
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• 제19권2호
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• pp.181-192
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• 2017

침식 및 퇴적과 관련된 수치모형을 이용한 분석은 하천에 존재하는 보와 같은 수리구조물들의 유사이송을 연구하는데 중요한 요소이다. 본 연구에서는 다기능보들의 효과적인 운영을 위하여 낙동강수계에 위치해 있는 강정고령보를 대상으로 하상변동을 예측하였다. 2차원 모형은 CCHE2D를 이용하여 유사이송이 지배적으로 발생하는 다기능보 상 하류 구간 25km를 대상으로 침식과 퇴적에 대한 모의를 수행하였다. 2006년 태풍 "에위니아"사상을 대상으로 모형을 검 보정 하였으며, 모의결과와 관측값의 비교를 통하여 전체 모의구간에서 신뢰성 있는 결과가 도출되었다. 강정고령보가 건설된 이후 태풍사상에 의한 하상변동은 가동보 구간에서 상당히 증가하는 것으로 나타났고 하상변동은 유사의 재분배를 야기하였다.

• 대기
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• 제18권4호
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• pp.299-316
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• 2008

The intensive upper-air observation network was organized over southwestern region of the Korean Peninsula during the Korea Enhanced Observing Program in 2005 (KEOP-2005). In order to examine the effect of additional upper-air observation on the numerical weather forecasting, three Observing System Experiments (OSEs) using Korea Local Analysis and Prediction System (KLAPS) and Weather Research and Forecasting (WRF) model with KEOP-2005 data are conducted. Cold start case with KEOP-2005 data presents a remarkable predictability difference with only conventional observation data in the downstream and along the Changma front area. The sensitivity of the predictability tends to decrease under the stable atmosphere. Our results indicates that the effect of intensive observation plays a role in the forecasting of the sensitive area in the numerical model, especially under the unstable atmospheric conditions. When the intensive upper-air observation data (KEOP-2005 data) are included in the OSEs, the predictability of precipitation is partially improved. Especially, when KEOP-2005 data are assimilated at 6-hour interval, the predictability on the heavy rainfall showing higher Critical Success Index (CSI) is highly improved. Therefore it is found that KEOP-2005 data play an important role in improving the position and intensity of the simulated precipitation system.