• 한국농공학회논문집
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• 제49권6호
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• pp.11-20
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• 2007

In order to make the way to determine the instream flow more practically, we have investigated many case studies and reviewed reports and papers. To validate instream flow level suggested by the case studies, DAWAST and HEC-RAS model were applied to the Gap-stream watershed in Daejeon city. Flow-duration analysis was performed both with the stream flow data gauged in the Indong, Boksu, and Hoeduck stations, and with the stream flow data estimated by the DAWAST model and the specific discharge method. Instream flow was determined among the flow-duration analysis, DAWAST, HEC-RAS model and mass balance approach. It was satisfied with various factors such as target water quality, water depth for eco-system and resorts, water surface width, flow velocity for landscape in dry season. The study suggested that the mean low flow could be replaced into the instream flow for the preliminary study because the instream flow considering ecosystem, landscape, water-friendly environment and water quality was generally close to the mean low flow.

• 한국방재학회 논문집
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• 제2권4호
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• pp.69-75
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• 2002

본 연구에서는 하천수질자료를 현장계측하고 무선으로 실시간 전송하여, GIS 상에서 자료를 분석하여 하천수질의 이상을 신속, 정확하게 파악하여 하천의 수질관리를 효율적으로 관리할 수 있는 GIS에 기반한 하천수질 관리시스템을 개발하였다. 시스템을 성능을 테스트할 목적으로 한강의 제1지류인 탄천을 시범유역으로 선정하여 개발된 시스템을 테스트하였다. 하천관리시스템은 크게 GPS 수신기가 탑재된 무선 실시간 계측시스템, 서버컴퓨터, GIS 시스템의 세 부분으로 나뉘어지며 각각의 시스템을 통합, 연계하여 최종 시스템을 개발하였다. 개발된 하천관리시스템을 시험유역에 적용한 결과 탄천 수질자료의 측정이 실시간으로 이루어짐과 동시에 서버컴퓨터에 저장되는 자료를 GIS 시스템 상에서 즉시 표출하고 가공할 있게 됨으로서 하천 수질을 실시간으로 관리할 수 있는 가능성을 제고하였으며 수질오염확산예측 및 수질방재등의 목적으로 활용할 수 있는 가능성을 확인하였다.

• 한국물환경학회지
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• 제36권2호
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• pp.98-108
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• 2020

The purpose of this study was to evaluate water quality in Hapcheon dam via using the Hydrological Simulation Program-Fortran (HSPF) model and applied livestock reduction scenarios. Hapcheon dam watershed input data for the HSPF model were established using the stream, land use, digital elevation map and meteorological data and others. The HSPF model was calibrated and validated using the observed water quality data from 2000 to 2016. For water quality simulation, we calculated the generated and discharge loads of the population, livestock, industry and land use following the guideline provided by the Ministry of Environment. The pollutant data were obtained from National Institute of Environmental Research (NIER). The monthly discharge load were estimated by applying the delivery rate. The calibration and validation results showed that the annual mean BOD had a difference of 0.22 mg/L and an error of ±13 %, T-N had a difference of 0.66 mg/L and an error of ±16 % and T-P had a difference of 0.027 mg/L and an error of ±13 %. In order to evaluate the nonpoint pollutants management effects, we applied livestock reduction scenarios because livestock consists of the largest portion of pollutants. As a result of the 20 % of livestock reduction, BOD, T-N and T-P decreased by 3 %, 1 % and 3 %, respectively. When 40 % of livestock reduction was applied, BOD, T-N and T-P decreased by 5 %, 3 % and 4 %, respectively. Based on the results of this study, effective pollutant management methods can be applied to improve the water quality and achieve the target water quality of Hapcheon dam watershed.

• 한국의학물리학회지:의학물리
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• 제7권2호
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• pp.19-28
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• 1996

정위적 방사선수술 (Stereotactic radiosurgery) 은 병소(region)의 위치를 정확히 결정하고 치료에 요구되는 방사선량이 정확히 전달되는 것이 중요하다. 본 연구는 이를 실험적으로 확인할 목적으로 특별히 고안된 물팬텀 (water phantom)을 개발하여 Leksell 정위기구 (Leksell Stereotactic Frame; LSF)에 부착하여 방사선수술을 시행하였다. 방사선 수술에는 Leksell 감마나이프 (Gamma Knife Unit; GKU) 와 LSF를 사용하였으며 실험을 위해 개발된 팬텀은 1mm 두께 플라스틱의 직경 160mm의 구형으로 물을 채울수 있는 구조로 되어있다. 측정장치로서는 목표점 설정(target localization)을 위한 필름과 전달 선량(dose delivery) 측정을 위해 이온 전리함(ionchamber) 을 사용하였으며 이를 팬텀의 목표점에 각각 위치시킬 수 있도록 설계하였다. 본 연구에서 목표점 확인은 허용 오차범위인 $\pm$0.5 mm 이내에서의 값을 보였으며 선량전달값은 $\pm$3% 정도의 오차로 허용값내에 있음을 보여주었다. 본 연구에서 개발된 팬텀으로 측정된 값이 모두 허용 오차범위 내에 있음을 보여주었고 이로인해 GKU 및 LSF의 주기적 QA(Quality Assurance)에 계속적으로 사용할수 있게 되었다.

• 한국물환경학회지
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• 제30권2호
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• pp.119-127
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• 2014

The objective of this study is to evaluate and analyze Sumjin River Basin water environment system. It was necessary to improve the water quality. The data were collected from 2010 January to 2012 December including Water Temperature, pH, DO, EC, $BOD_5$, COD, TOC, SS, T-N, T-P. The data were used to study were required to; Correlation Analysis; Principle Component Analysis; Factor Analysis. The results were as followed. According to correlation analysis on $BOD_5$ against COD, TOC it revealed that the each value of correlation coefficient were 0.715 and 0.719; this means the strength of the relationship is strong. The same analysis on T-P against $BOD_5$, COD, TOC, SS has revealed that the range of the correlation coefficient value fell between 0.482 and 0.608 which means strength of the relationship between them remained normal. Through correlation analysis, it has been found that all elements except T-N have high correlation. The results of principal component analysis to target the overall water quality was extracted to three main components. The cumulative contribution rate is 68.990%. In the case of seasonal water quality, Spring and Summer are extracted to each of four main components. The cumulative contribution rate is 81.515% and 73.550% respectively. Fall and Winter are extracted to each of three main components. The cumulative contribution rate is 65.072% and 72.721% respectively. There is no seasonality in the case of factor analysis. The first common factor is $BOD_5$, COD, TOC, SS, T-P, which were classified. Totally speaking, Sumjin River Basin water system gets highly affected by the nutrient salts, organic matter and suspended solid at the same time.

• 한국수자원학회논문집
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• 제54권10호
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• pp.769-777
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• 2021

본 연구에서는 낙동강 유역의 수질관리에 미치는 기상학적 가뭄의 영향을 평가하였다. 3개의 가뭄지수(30일-, 60일-, 90일-표준강수지수)를 바탕으로 심한 가뭄의 발생여부를 판단하고, 생화학적산소요구량(BOD), 총유기탄소량(TOC), 그리고 총인(T-P)에 대한 목표수질 달성비율을 분석하여, 계절에 따른 중권역의 심한 가뭄 발생이 수질관리에 큰 영향을 미치는 지역을 구분하였다. 이러한 중권역에 대하여 베이지안 네트워크 모형을 이용한 가뭄-수질관리 간의 인과관계를 확률론적으로 해석하였다. 낙동강유역의 22개 중권역 중 4개의 중권역(#2005(영강), #2018(남강댐), #2021(밀양강), #2022(낙동강하구언))이 심한가뭄에 대한 수질관리에 취약성이 큰 것으로 나타났다. 또한, 봄과 가을철 수질관리에 미치는 가뭄의 영향이 가장 큰 지역은 #2021, 여름철은 #2005, 겨울철은 #2022인 것으로 나타났다. 이러한 가뭄과 수질관리 간의 인과관계에 대한 분석결과는 사전적 가뭄관리에서의 활용도가 클 것이다.

• 한국관개배수논문집
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• 제14권2호
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• pp.181-193
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• 2007

The characteristics of non-point source pollutant loads in middle-stream of Nakdong River Were studied through analysis of pollutant loads of 8 sub-watersheds divided based on administrative district. The pollutant concentration of each sub-watershed was collected from Nakdong-River Water Research Institute and Daegu Regional Environmental Office, respectively. Pollution items analysed in this study were BOD, SS, T-N and T-P. High degree of non-point pollution was observed from Gumi, Goryeong, Gyeongsan, Daegu and Sungju, and pollution was usually increased during rainy season. This result indicates that a given pollution condition within the watershed can be more sensitive than location factor to the level of water quality. The main sources of non-point pollution were population and livestock, as well as landuse factor, and were found to significantly contribute to the water pollution. Alternative solutions for controlling pollution sources, therefore, should be provided to meet target levels of water quality in this region.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.1355-1359
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• 2010

The purpose of this study is to analyze the spatial characteristics of Namgang-Dam watershed for a Total Maximum Daily Loads(TMDL). Three TMDL target sites, Gyeonghogang1, 2, Namgang-Dam2, are located within Namgang-Dam watershed. Under the current criterion for TMDLs, 3-year arithmetic mean BOD concentration of the target sites should not exceed the target concentration for 2 consecutive years. Two and three times of violation were observed for Gyenghogang2 and Namgang-Dam2 sites while no violation was found for Gyeonghogang1 site. However, no violation was found since 1999 for all three sites. Correlation between each 12 stations within the watershed were analyzed and cluster analysis was conducted to figure out the spatial characteristics of the watershed. Correlation coefficient between Gyonghogang1 and 2 was high (0.758) while the coefficients between lake station (Namgang-Dam2) and stream stations (Gyonghogang1 and 2) were very low. Dendrogram indicated that all of three Namgang-Dam stations were very close and Gyenghogang1, 2 stations were also close.

• 한국엔터테인먼트산업학회논문지
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• 제15권3호
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• pp.289-295
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• 2021

오늘날 인간의 삶의 질에 가장 중요하게 미치는 요인은 환경에서 기인된다고 생각된다. 기후변화와 지구 온난화 현상에 따른 폭우, 대설, 지진 등으로 장마, 태풍, 벌채면 붕괴, 미세먼지 등의 발생 빈도가 증가하여 피해 규모가 해마다 커짐에 따라 환경 분석 및 감시 시스템의 중요성은 날로 커지고 있다. 환경의 문제들 중 물(수질)에 의해 발생하는 문제는 그 비중이 매우 높은 바, 도시화, 산업화로 수질 오염사고 발생 때 피해 규모가 대형화 되었으며 사람들 사이에 물 안전망에 대한 우려가 증가하고 있다. 최근 5년간 4대강 유역에서 수질 오염 사고 359건(한강 129, 낙동강 51, 금강 25, 섬진강 및 영산강 19, 기타 85)이 발생하였으며, 이로 인해 물 공급 정지 및 오염된 수돗물 공급 등 사회 전반에 걸처 환경에 직간접적인 피해를 야기하였다. 따라서, 현재 4대강 중심의 수질(물) 관리 시스템에서 중소하천, 지류/지천, 저수지 등으로 수질 모니터링 대상을 확대 함 으로서수질 환경의 불확실성을 최소화할 수 있는 빅데이터 기반 수질 환경 관리 전략체계의 구축이 요구된다. 본 논문에서는 기존의 오랜 기간 축적하여 온 수질 정보 빅데이터를 이용한 인공신경망 미들웨어 구축을 통하여 유용한 수질 분석 정보를 제시 할 수 있는 수질 모니터링 미들웨어 구축방안을 제시하고자 한다.

• Environmental Engineering Research
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• 제16권3호
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• pp.121-129
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• 2011

The completely mixed flow and plug flow (CAP) water quality model was developed for streams with discontinuous flows, a condition that often occurs in low base flow streams with in-stream hydraulic structures, especially during dry seasons. To consider the distinct physical properties of each reach effectively, the CAP model stream network can include both plug flow (PF) segments and completely mixed flow (CMF) segments. Many existing water quality models are capable of simulating various constituents and their interactions in surface water bodies. More complicated models do not necessarily produce more accurate results because of problems in data availability and uncertainties. Due to the complicated and even random nature of environmental forcing functions, it is not possible to construct an ideal model for every situation. Therefore, at present, many governmental level water quality standards and decisions are still based on lumped constituents, such as the carbonaceous biochemical oxygen demand (CBOD), the total nitrogen (TN) or the total phosphorus (TP). In these cases, a model dedicated to predicting the target concentration based on available data may provide as equally accurate results as a general purpose model. The CAP model assumes that its water quality constituents are independent of each other and thus can be applied for any constituent in waters that follow first order reaction kinetics. The CAP model was applied to the Geum River in Korea and tested for CBOD, TN, and TP concentrations. A trial and error method was used for parameter calibration using the field data. The results agreed well with QUAL2EU model predictions.