• 한국물환경학회지
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• 제24권4호
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• pp.430-435
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• 2008

In order to design Non-point source management, the aspect of statistical features of the entire precipitation data should be focused since non-point source discharge is driven by continuous rainfall runoffs. 3-parameter mixed exponential probability density function is used to establish urban stormwater capture curve instead of previous single-parameter exponential PDF. Then, recent 10-year data in Busan are applied to establish the curve. The result shows that 3-parameter mixed PDF gives better resolution.

• 한국농공학회지
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• 제41권6호
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• pp.44-53
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• 1999

The statistical characteristics of the factors related to the daily rainfall prediction model are analyzed . Records of daily precipitation, mean air temperature, relative humidity , dew-point temperature and air pressure from 1973∼1998 at 8 meteorological sttions in south-western part of Korea were used. 1. Serial correlatino of daily precipitaiton was significant with the lag less than 1 day. But , that of other variables were large enough until 10 day lag. 2. Crosscorrelation of air temperature, relative humidity , dew-point temperature showed similar distribution wiht the basin contrours and the others were different. 3. There were significant correlation between the meteorological variables and precipitation preceded more than 2 days. 4. Daily preciption of each station were treated as a truncated continuous random variable and the annual periodic components, mean and standard deviation were estimated for each day. 5. All of the results could be considered to select the input variables of regression model or neural network model for the prediction of daily precipitation and to construct the stochastic model of daily precipitation.

• 토지주택연구
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• 제11권1호
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• pp.103-108
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• 2020

Autonomous things system is a technology that judges and acts based on using surrounding information by itself, and it is evaluated as a future technology that can replace the current IoT technology. The current IoT technology is widely used from facility monitoring to machine control but it is shown weakness as a evaluation and prediction technique despite of smart city important technology. In this study, in order to confirm the application of the autonomous things technology, a monitoring system was installed on a real reservoir dam facility and long-term monitoring was performed that the measuring device itself judges and control as a facility monitoring technology. The autonomous things technology was confirmed during 19 months and it is possible to continuous measurement in the same way as current automated instrumentation. In addition, it was confirmed that the ICT device itself could to control autonomously measurement cycle according to the rainfall by itself.

• 지질공학
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• 제22권3호
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• pp.343-351
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• 2012

본 연구는 기존에 제안된 무한사면 안정해석식을 바탕으로 불포화토 내에 강우침투 시 지표로부터 시간에 따른 토층의 포화깊이비를 새로운 변수로 삽입하여 무한사면 안정해석 수정식을 제안하고자 하였다. 이를 위해 기존에 고려하지 못했던 시간에 따른 포화깊이비와 지표하 흐름 깊이의 개념을 새로이 도입하였으며, 유사동력학적 습윤지수 이론에서 도출되는 해석대상 지역의 유효상부기여면적, 지표하흐름 깊이, 포화깊이비를 계산하고, 이를 토대로 시간에 따른 포화깊이비를 반영한 무한사면 안정해석을 수행하도록 하였다. 이를 통해 실질적인 시간에 따른 강우의 변화양상과 사면 안전율 변화를 계산할 수 있게 되었다. 한편, 본 연구에서는 Park et al. (2011 a)가 실시한 불포화토 칼럼시험을 통한 강우침투 속도분석 결과를 바탕으로 본 연구에서 제안한 식을 이용하여 토층의 포화깊이비를 고려한 사면안정해석을 실시하였다. 이 해석을 통해 편마암 풍화토의 토층 내 강우 침투속도를 고려하여 포화깊이비가 변화함에 따른 안전율의 변화를 파악할 수 있었다. 해석결과에 의하면, 연속강우의 경우 안전율이 1.3 이하로 감소하는 시간이 강우강도 20 mm/h 조건에서 2.86 ~ 5.38시간이고, 강우강도 50 mm/h 조건에서는 1.34 ~ 2.92시간으로 나타났다. 반복강우의 경우, 안전율이 1.3 이하가 되는 시간은 강우조건별로 3.27 ~ 5.61시간으로 나타났다. 따라서, 토층 내 강우침투속도 차이에 따른 포화깊이비 변화를 고려한 무한사면의 안전율 변화 파악이 가능하였다.

• 한국수자원학회논문집
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• 제37권7호
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• pp.599-612
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• 2004

유역규모의 장기 유출모형인 SWAT은 다양한 토지이용을 고려할 수 있는 장점이 있는 반면, 도시지역에 대한 배수특성을 충분히 고려할 수 없는 단점을 가지고 있다. 반면, 세계적으로 도시지역의 유출현상 규명에 널리 이용되는 SWMM 모형은 도시지역의 지표면 특성과 배수특성을 모두 고려할 수 있는 장점이 있는 반면 유역 내 도시지역 이외의 토지이용에 대한 고려가 힘들다는 단절이 있다. 본 연구에서는 두 모형의 장점을 살리고, 단점을 보완한 SWAT-SWMM 결합모형을 경안천내 오산천 유역에 적용하였다. 이로부터 SWAT-SWMM 결합모형에 대한 모식결과와 SWAT 모형에 의한 모의결과를 증발산, 지표면유출량, 토양으로부터의 유출량, 유역 및 하도 유출량 등 수문성분별로 비교ㆍ평가하였고, 두 모형의 수문성분별 유출모식의 특징에 대하여 논의하였다

• 한국물환경학회지
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• 제29권3호
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• pp.354-364
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• 2013

The performance of the stormwater wetlands can be significantly influenced by antecedent stormwater in storage at the commencement of a stormevent. As inflows are intermittent and stochastic in nature, the evaluation of the treatment efficiency of a stormwater wetland should be considered by runoff capture and water treatment characteristics during interevent periods. In this study, analytical probabilistic model is applied to identity runoff capture rate and treatment efficiency of the stormwater wetland. To achieve this, continuous rainfall data recorded in Busan for 31 years has been analyzed to derive the runoff capture rate, and 1st order kinetic decay constants ($k_V$, 1/d) are calculated from regression analysis to identify pollutants removal during interevent periods. The results show that about 60.9% of annual average runoff is captured through the stormwater wetland. The annual average treatment efficiencies of SS, BOD, COD, TN and TP is about 11.4, 8.9, 9.8, 4.3 and 9.6%, respectively. The analytical model has been compared with the numerical model and it shows that analytical model is valid. Performance evaluation methods developed in this study has the advantages of considering characteristics of rainfall-runoff, facility type and pollutant removal.

• 한국농공학회논문집
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• 제54권6호
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• pp.29-37
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• 2012

This study was carried out to runoff characteristics in an upland livestock manure compost. Irrigation, runoff and water quality data in the upland were analyzed periodically from May to November in 2011. The observed amount of rainfall, irrigation, runoff for the experimental upland during the investigation period were 1,299.7 mm, 32.0 mm, and 340.7 mm, respectively. The concentrations of T-N in compost and non-compost upland during study period were ranged from 2.09 mg/L to 6.66 mg/L and from 1.99 mg/L to 6.01 mg/L, respectively. which was generally higher than the quality standard of agricultural water (1.0 mg/L). The concentrations of T-P in compost and non-compost upland during study period were ranged from 0.069 mg/L to 0.525 mg/L and from 0.018 mg/L to 0.152 mg/L, respectively. The runoff pollutants loadings of T-N and T-P in compost upland were 10.05 kg/ha and 0.56 kg/ha, respectively. The runoff pollutants loadings of T-N and T-P in non-compost upland were 9.09 kg/ha and 0.26 kg/ha, respectively. The runoff pollutants loadings in T-N and T-P from this study were much lower values than the pollutant loadings of T-N and T-P from the upland published by the others studies. Runoff pollution loadings due to the upland field in order to identify the characteristics of various crops, farming methods and a variety of targets taking into account regional characteristics by conducting continuous monitoring runoff load estimate will be required.

• 한국농공학회논문집
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• 제50권2호
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• pp.65-71
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• 2008

A monsoon season monitoring data from June to September, 2005 of a small forested watershed located at the upstream of the North Han River system in Korea was conducted to analyze the flow variations, the NPS pollutant concentrations, and the pollution load characteristics with respect to sampling frequencies. During the 4-month period, 1,423 mm or 79.2% of annual rainfall(1,797 mm) were occurred and more than 77%, 54% and 68% of annual T-N, $NO_3$-N and T-P loads discharged. Flow rate was continuously measured with automatic velocity and water level meters and 58 water quality samples were taken and analyzed. It was analyzed that the flow volume by random measurement varied very widely and ranged from 79% to 218% of that of continuous measurement. It was recommended that flow measurement of small forested watersheds should be continuously measured with automated flow meters to precisely measure flow rates. Flow-weighted mean concentrations of T-N, $NO_3$-N and T-P during the period were 2.114 mg/L, 0.836 mg/L, and 0.136 mg/L, respectively. T-N, $NO_3$-N and T-P loads were sensitive to the number of samples. And it was analyzed that in order to measure the pollution load within the error of 10% to the true load, the rate of sampling frequency should be higher than 89.7% of the sample numbers that were required to compute the true pollution load. If it is compared to selected foreign research results, about 10 water samples for each rainfall event were needed to compute the pollution load within 10% error. It is unlikely in Korea and recommended that thorough NPS pollution monitoring studies are required to develop the standard monitoring procedures for reliable NPS pollution quantification.

• 한국토양비료학회지
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• 제49권4호
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• pp.310-317
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• 2016

This study aimed to evaluate the nutrient load balance from rice paddy fields with different topographies, alluvial plain and local valley. Continuous monitoring from May to September, 2013 was conducted for water quantification and qualification from alluvial plain in Yeoju region (32 ha) and local valley in Jincheon region (24 ha). The discharge rates of T-N from the alluvial plain were 57.2, 5.84, 22.7, and $5.20kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In case of local valley, T-N loads were 34.6, 4.73, 21.1, and $4.15kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In contrary, the T-P loads from the alluvial plain were 2.23, 2.22, 2.54, and $0.41kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In case of local valley, T-P loads were 1.44, 1.57, 1.82, and $0.34kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. The nutrient contents in drainage water were influenced by the amount of waters, rainfall, and surface drainage water. The Pearson correlation analysis showed that rainfall was significantly correlated with nutrient loads from July to August due to the amount of runoff in local valley paddy field, and irrigation was related with nutrient loads of drainage from July to August. This study showed that paddy rice farming in alluvial plain and local valley might be beneficial to water quality protection.

• 대한공간정보학회지
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• 제15권3호
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• pp.69-76
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• 2007

강원도 지역은 산지지형이 많고 여름철 장마나 이상기후에 의한 국지적인 집중호우에 의해서 산사태가 발생하기 쉬운 조건을 가지고 있으며 최근, 수년간 계속되고 있는 대형 산불들로 인하여 지표상태가 변화되어 강우사상에 의해 쉽게 산사태가 일어나고 있다. 또한 앞서 발표된 연구논문에 의하면 우리나라의 경우 강우조건을 제외하고는 토지피복상태가 산사태 취약성 평가에 가장 큰 영향을 미치는 것으로 보고되고 있다. 따라서 이 연구에서는 산사태 취약지를 선정하고 산사태 취약 A등급지에 대해서 4개의 서로 다른 시기에 촬영된 인공위성 영상(Landsat ETM)으로 부터 토지 피복도를 추출하여 그 분포변화를 분석하였다. 또한 정규식생지수를 추출하고 식생활력도의 분포변화를 분석하여 지표상태의 변화가 산사태에 미치는 영향을 분석하고자 하였다. 그 결과 산사태 취약지에서 산림과 식생지수가 감소하고 있음을 알 수 있었다.