• 한국습지학회지
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• 제21권spc호
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• pp.90-97
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• 2019

최근 연속적인 호우사상으로 인해 홍수가 발생하고 있으며, 이로 인한 재산 및 인명피해가 증가하고 있다. 따라서 본 연구에서는 연속적인 호우사상 발생 사례를 바탕으로 거대강우 시나리오와 거대홍수를 정의하였다. 경안천 유역의 100년 빈도 확률강우사상이 연속적으로 발생한다는 가정하에 거대강우 시나리오를 생성하였으며, 거대홍수량을 산정하기 위하여 SSARR(Streamflow Synthesis and Reservoir Regulation)모형을 이용하였다. 또한, 보다 합리적인 유출해석을 수행하기 위하여 SCE_UA기법을 통해 매개변수를 추정하고, SSR(Sum of Squared of Residual)과 첨두유량 모의에 유리한 WSSR(Weighted Sum of Squared of Residual)의 목적함수를 이용하여 모형의 보정 및 검증을 수행하였다. 이를 통해 적합성 검토를 수행하였다. 그 결과, 경안천 유역의 100년 빈도 강우사상의 연속발생으로 인한 거대홍수량은 4,802㎥/s로 산정되었고, 경안천하천정비기본계획(2011)에서 산정한 100년 빈도 단일 강우사상에 의한 홍수량은 3,810㎥/s으로 산정되었다. 따라서 거대홍수량이 단일 호우사상에 의한 홍수량 보다 약 992㎥/s 만큼 증가하는 것으로 확인되었으며, 이는 향후 거대홍수를 고려할 경우, 경안천 유역의 치수방어대책 수립시 참고자료로 활용할 수 있을 것으로 기대된다.

• 한국환경보건학회지
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• 제31권1호
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• pp.15-22
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• 2005

This study was conducted to evaluate air injection mode on stabilization of solid waste in lysimeter. For three lysimeters, one was maintained under anaerobic condition as control, and air was injected into two lysimeters in continuous mode (atmospheric pressure) and intermittent mode (high pressure of 2 bar). Distilled water was sprayed over solid waste in 1.4 l/$m^3$(solid waste)/day, supposing rainfall intensity of 1,200 mm/yr and 30% infiltration. Oxygen in landfill gas was not detected in control lysimeter during operational days. After 30 day-aeration, oxygen concentrations of continuous and intermittent modes were maintained in 14% and 6%, respectively. $COD_{Cr}$ removal efficiencies of continuous and intermittent modes were about 70% and 50%, and BOD5 removal efficiencies were about 80% and 20%, respectively. In view of oxygen supply, and $COD_{Cr}$ and $BOD_5$ removal, continuous air injection mode of atmospheric pressure was more effective than intermittent mode of 2 bar. Settling degree of solid waste in case of two air injection modes was 3 times higher than that of anaerobic condition as control. Considering the above results, it was thought that air injection (especially continuous atmospheric pressure) could improve degradation of solid waste and induce preliminary stabilization in landfill site.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.334-334
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• 2022

Improvement of old-fashioned rain gauge systems for automatic, timely, continuous, and accurate precipitation observation is highly essential for weather/climate prediction and natural hazards early warning, since the occurrence frequency and intensity of heavy and extreme precipitation events (especially floods) are recently getting more increase and severe worldwide due to climate change. Although rain gauge accuracy of 0.1 mm is recommended by the World Meteorological Organization (WMO), the traditional rain gauges in both weighting and tipping bucket types are often unable to meet that demand due to several existing technical limitations together with higher production and maintenance costs. Therefore, we aim to introduce a newly developed and cost-effective hybrid rain gauge system at 0.1 mm accuracy that combines advantages of weighting and tipping bucket types for continuous, automatic, and accurate precipitation observation, where the errors from long-term load cells and external environmental sources (e.g., winds) can be removed via an automatic drainage system and artificial intelligence-based data quality control procedure. Our rain gauge system consists of an instrument unit for measuring precipitation, a communication unit for transmitting and receiving measured precipitation signals, and a database unit for storing, processing, and analyzing precipitation data. This newly developed rain gauge was designed according to the weather instrument criteria, where precipitation amounts filled into the tipping bucket are measured considering the receiver's diameter, the maximum measurement of precipitation, drainage time, and the conductivity marking. Moreover, it is also designed to transmit the measured precipitation data stored in the PCB through RS232, RS485, and TCP/IP, together with connecting to the data logger to enable data collection and analysis based on user needs. Preliminary results from a comparison with an existing 1.0-mm tipping bucket rain gauge indicated that our developed rain gauge has an excellent performance in continuous precipitation observation with higher measurement accuracy, more correct precipitation days observed (120 days), and a lower error of roughly 27 mm occurred during the measurement period.

• 농업과학연구
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• 제2권1호
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• pp.281-300
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• 1975

1. 금강유역(錦江流域)의 평균년강수량(平均年降水量)은 1203.0mm이고, 면적강수량(面積降水量)을 산출(算出)할 때 많이 사용(使用)하는 Thiessen법(法)의 Areal weight는 표(表)-과 같다. 2. 최대연강수량(最大年降水量)은 1501~2000mm인 곳이 24개관측소중(個觀測所中)며 17개소(個所)나 되어 가장 많은 71%이고, 나머지는 1500mm이하(以下)인 곳이 3개소(個所)이며, 2001mm이상(以上)인 곳은 4개소(個所)이다. 3. 최대일강우량(最大日降雨量)은 201~300mm인 곳이 15개소(個所)로 가장 많은 63%의 분포(分布)이다. 4. 최대(最大)2일간연속강우량(日間連續降雨量)은 300mm를 중심(中心)으로 전후(前後) 각각 50%씩 분포(分布)된다. 5. 최대(最大)3일간연속강우량(日間連續降雨量)은 301~400mm인 곳이 15개소(個所)로 63%의 분포(分布)이며 이는 최대일강우량(最大日降雨量)보다 100mm가 더 많은 강우량(降雨量)이다. 6. 최대연속강우량(最大連續降雨量)은 401~600mm인 곳이 14개소(個所)로 가장 많은 58%의 분포(分布)이며 이는 최대일강우량(最大日降雨量)보다 200mm가 더 많은 강우량(降雨量)이다. 7. 확률일강우량(確率日降雨量)은 표(表)-5와 같고, 무주(茂朱)를 중심(中心)으로한 대청(大淸)댐유역(流域)의 확률일강우량(確率日降雨量)이 가장 많으며, 다음으로는 강경(江景) 공주(公州) 및 부여(扶餘)를 연결(連結)하는 지방(地方)이 다우(多雨)인 편(便)이다. 8. 6월(月)1일(日)부터 9월(月)10일(日)까지 100일간(日間)의 논벼 관개기간중(灌漑期間中)의 강우량(降雨量)은 601~800mm 인 곳이 16개소(開所)로 76%의 분포(分布)이며 이는 표(表)-6과 같다. 9. 유효우량(有效雨量)은 501~600mm인 곳이 15개소(個所) 71%의 분포(分布)이며, 유효율(有效率)은 66~75%인 곳이 13개소(個所)로 62%의 비율(比率)이고, 다음으로는 76~85%인 곳이 7개소(個所)로 33%의 비율(比率)이다. 10. 확률유효우량(確率有效雨量)은 각 지방(地方)의 연평균유효우량(年平均有效雨量)은 보다 100mm정도(程度)씩 적고, 301~500mm인 곳이 14개소(個所)로 67%의 분포(分布)이다. 11. 갈수년도(渴水年度)는 유역내(流域內)를 총괄적(總括的) 동일(同一)하게 지정(指定)할수 없다고 여겨진다. 12. 금강유역(錦江流域)의 s/S는 0.53~0.74로 되어 수자원면(水資源面)에서 비교적(比較的) 안정(安定) 편(便)이다.

• 물과 미래
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• 제18권1호
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• pp.85-94
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• 1985

수치해법와 경험적 방법을 합성함으로써 하천수문곡선의 기저유출을 분리하는 방법을 개발하였다. 기저유출 감수곡선에 대해서는 선형화된 Boussinesq 방정식과 저유함수를 적용하였으며, 또한 강우에 의하여 지하의 대수층에 침투된 량이 하천으로 유입되는 기저유출의 추정에는 Singh과 Stall의 도식적 방법을 이용하였다. 이들에대한 시간별 연속성은 다원적인 다항식 회귀론에 의하여 근사화시켰다. 본 연구과정은 자연하천에 성공적으로 적용할 수 있었으나, 감수곡선을 위한 동차선형2단상징분계의 직접적 수치해법은 부적합한 것으로 나타났으며, 손실이 발생되는 부분침투천의 기저유량은 본 연구방법에 의하여 추정할 수 없었다.

• 한국물환경학회지
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• 제25권4호
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• pp.573-579
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• 2009

The performance of Rainfall-Runoff Forecasting System (RRFS), the watershed management model for the Geum river basin, is evaluated based on the agreement between the simulated and observed hydrographs and the behavioral characteristics of the flow-duration curves. As a result, the simulated hydrographs are well agreed with the observed ones except high flow discharges. It is inferred that most of the errors in the simulated hydrographs are due to the misestimation of agricultural water use in $2^{nd}$ quarter and the discrepancy of the peak discharges in $3^{rd}$ quarter. It is however judged that RRFS would give the reliable runoff hydrographs from the point of view of continuous model application. And simulated flow-duration curves and flow-duration coefficients are also similar to the observed ones except flood flow region. From the above result it is confirmed that the construction of Yongdam dam improves the state of flow-duration curve at the Gongjoo station.

• 한국산학기술학회논문지
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• 제15권5호
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• pp.3159-3168
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• 2014

비점오염원 관리를 위한 독립호우의 결정은 월류수 처리시설의 설계에서 필수적이다. 비점오염원의 관리를 위해서는 총량을 결정해야만 하는데 이를 위해서는 결정된 독립호우에 의해 1회 평균강우량, 평균강우강도, 평균지속시간 등의 강우특성의 분석이 실시되어야만 한다. 독립호우의 결정은 무강우 지속시간의 산정(Interevent Time Definition, IETD)에 따라 분리할 수 있으며 이를 결정하기 위한 기존의 분석방법에는 자기상관 분석, 변동계수 분석, 연강우 평균발생횟수 분석 등이 있다. 본 연구에서는 기존의 IETD 분석방법에 따라 무강우시간을 산정한 후 방법별 문제점을 고찰하고 새로운 IETD 결정방법으로 지수함수 검정방법을 제안하였다. 또한, 검정방법을 통하여 결과값의 적절성을 검토하였다.

• 한국농공학회논문집
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• 제63권3호
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• pp.75-85
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• 2021

This study evaluated variations in the paddy rice water demand based on the continuous changing in rice transplanting period and ponding depth at the four study paddy fields, which represent typical rice producing regions in Korea. Total 7 scenarios on rice transplanting periods were applied while minimum ponding depth of 0 and 20 mm were applied in accordance with maximum ponding depth ranging from 40 mm to 100 mm with 20 mm interval. The weather data from 2013 to 2019 was also considered. The results indicated that the highest rice water demand occurred at high temperature and low rainfall region. Increased rice transplanting periods showed higher rice water demand. The rice water demand for 51 transplanting days closely matched with the actual irrigation water supply. In case of ponding depth, the results showed that the minimum ponding depth had a proportional relationship with rice water demand, while maximum ponding depth showed the contrary results. Minimum ponding depth had a greater impact on rice water demand than the maximum ponding depth. Therefore, these results suggest that increasing the rice transplanting period, which reflects the current practice is desirable for a reliable estimation of rice water demand.

• 한국농공학회지
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• 제32권4호
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• pp.27-43
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• 1990

This study aimed at developing a generalized model on the estimation of the long - term run - off volume for practical purpose. During the research period of last 3 years( 1986-1988), 3 types of estimation model on the long - term run - off volume(Effective rainfall model, unit hydrograph model and barne's model for dry season) had been developed by the author. In this study, through regressional analysis between determinant factors (bi of effective rainfall model, ai of unit hydrograph model and Wi of barne's model) and catchment characteris- tics(catchment area, distance round the catchment area, massing degree coefficient, river - exte- nsion, river - slope, river - density, infiltration of Watershed) of 11 test case areas by multiple regressional method, a new methodology on the derivation of determinant factors from catchment characteristics in the watershed areas having no hydrological station was developed. Therefore, in the resulting step, estimation equations on run - off volume for practical purpose of which input facor is only rainfall were developed. In the next stage, the derived equations were applied on the Kang - and Namgye - river catchment areas for checking of their goodness. The test results were as follows ; 1. In Kang - river area, average relative estimation errors of 72 hydrographs and of continuous daily run - off volume for 245 days( 1/5/1982 - 31/12) were calculated as 6.09%, 9.58% respectively. 2. In Namgye - river area, average relative estimation errors of 65 hydrographs and of conti- nuous daily run - off volume for 2fl days(5/4/1980-31/12) were 5.68%, 10.5% respectively. In both cases, relative estimation error was averaged as 7.96%, and so, the methodology in this study might be hetter organized than Kaziyama's formula when comparing with the relative error of the latter, 24~54%. However, two case studies cannot be the base materials enough for the full generalization of the model. So, in the future studies, many test case studies of this model should he carries out in the various catchment areas for making its generalization.

• 한국환경과학회지
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• 제22권5호
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• pp.639-649
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• 2013

Over 96.2% of the agricultural water in Jeju Island is obtained from groundwater and there are quite distinct characteristics of agricultural water demand/supply spatially because of regional and seasonal differences in cropping system and rainfall amount. Land use for cultivating crops is expected to decrease 7.4% (4,215 ha) in 2020 compared to 2010, while market garden including various vegetable crop types having high water demand is increasing over the Island, especially western area having lower rainfall amount compared to southern area. On the other hand, land use for fruit including citrus and mandarin having low water demand is widely distributed over southern and northern part having higher rainfall amount. The agricultural water demand of $1,214{\times}10^3\;m^3/day$ in 2020 is estimated about 1.39 times compared to groundwater supply capacity of $874{\times}10^3\;m^3/day$ in 2010 with 42.4% of eastern, 103.1% of western, 61.9% of southern, and 77.0% of northern region. Moreover, net secured amount of agricultural groundwater would be expected to be much smaller due to regional disparity of water demand/supply, the lack of linkage system between the agricultural water supply facilities, and high percentage of private wells. Therefore, it is necessary to ensure the total net secured amount of agricultural groundwater to overcome the expected regional discrepancy of water demand and supply by establishing policy alternative of regional water supply plan over the Island, including linkage system between wells, water tank enlargement, private wells maintenance and public wells development, and continuous enlargement of rainwater utilization facilities.