• Nuclear Engineering and Technology
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• 제55권2호
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• pp.707-716
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• 2023

The influence of waste technological waters of thermal and fast reactors of Beloyarsk NPP (Russia) on the accumulation of ⁶⁰Co, ⁹⁰Sr and ¹³⁷Cs in macrophytes and ichthyofauna of the cooling pond has been studied. Critical radionuclides, routes of their entry into the ecosystem and periods of maximum discharge of radioisotopes into the cooling pond have been determined. It is shown that the technology of electricity generation at the Beloyarsk NPP, based on fast reactors, has a much smaller effect on the release of artificial radionuclides into the environment. Therefore, during the entire period of monitoring studies (1976-2019), the decrease in the specific activity of radionuclides of NPP origin in macrophytes was 13-25800 times, in ichthyofauna 1.5-44.5 times. The maximum discharge of artificial radionuclides into the Beloyarsk reservoir was noted during the period of restoration and decontamination work aimed at eliminating the emergencies at the AMB reactors of NPP. The factors influencing the accumulation of artificial radionuclides in the components of the freshwater ecosystem of the Beloyarsk cooling pond have been determined, including: the physicochemical nature of radioisotopes, their concentration in surface water, the temperature of the aquatic environment, the trophicity of the reservoir, the species of hydrobionts.

• 한국지열·수열에너지학회논문집
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• 제8권2호
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• pp.55-60
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• 2012

In many cases, geothemal wells will not be opened up a geothermal reservoir under such conditions that an extraction of geothermal energy is economically viable without any further measures. Geothermal wells often have to be stimulated, in order to increase productivity. For the non-volcanic area, such as Korea, the hydraulic stimulation is necessary to complete geothermal power plant. The analysis of induced seismic event showed that the thermal resource might have a much wider extent and a much higher generation potential than previously assumed. In order to record compressional and shear waves emitted during fracture stimulation, three-component geophones are placed in a seismometer. The recorded data from one seismometer is the convolution of the source magnitude, the transmission media, and the sensitivity of the instrument.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.505-508
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• 2006

Recently, concern for tidal power is being increased by newly recycled energy. It is important to decide on the maximum power estimate operation and it's stop by applying the difference of water level between tide level and artificial reservoir for the administration of tidal development. For maximum output of power through turbine generator, administrative variables and process on efficiency of hydraulic turbine and inflow discharge of reservoir is quite complicated because it is run through the connection of discharge-gate and turbine On the development of this model, the administrative process is decided, Operation block is presented for it's maximum power estimate.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1532-1548
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• 2008

The tunnel type spillways is under construction to increasing water reservoir capacity in Dae-am dam. The tunnel outlet was planned to be made after installing slope stabilization system on natural slope there. Generally, the tunnel outlet is made perpendicularly to the slope, but in this case, it had to be made obliquely to the slope for not interrupting flow of river. Because of excavation in condition of natural slope caused to deflecting earth pressure, the outlet couldn't be made. So, artificial ground made with concrete that it was constructed in the outside of tunnel for producing the arching effect which enables to make a outlet. We were planned tunnel excavation was carried out after artificial ground made. Artificial ground made by poor mix concrete of which it was planned that the thickness was at least 3.0m height from outside of tunnel lining and 30cm of height per pouring. Spreading and compaction was planned utilized weight of 15 ton roller machine. In order to access of working truck, slope of artificial ground was designed 1:1.0 and applied 2% slope in upper pert of it for easily drainage of water. In addition to, upper pert of artificial ground was covered with soil, because of impaction of rock fall from upper slope was made minimum. The tunnel excavation of the artificial ground was designed application with special blasting method that it was Super Wedge and control blasting utilized with pre-percussion hole.

• 한국측량학회지
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• 제31권6_1호
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• pp.439-446
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• 2013

본연구는 관개용 저수지의 토사유실량을 산정하기 위해 GIS를 이용하였다. 토사유실로 인한 재해는 산지녹화사업의 성공으로 인하여 자연적인 토사재해는 급감하고 있으나, 최근의 기상이변에 따른 국지성 호우와 인위적인 개발사업은 토사재해발생의 직접적인 요인으로 작용하여 높은 재해위험도를 나타내고 있다. 이를 방재하기 위하여 다양한 기법과 기술을 사용하여 토사유실에 따른 영향을 예측하고 있으나 토사유실에 따른 재해는 잠재적인 요인과 직접적인 요인의 복잡한 상호작용으로 발생되고 있어 이를 명확하게 규명할 수 있는 예측방법의 신뢰도는 상대적으로 낮은 편이다. 토사유실에 대한 복잡한 상호작용을 명확하게 규명하기 위해서는 대상지역의 지형정보학적 접근이 필수적임으로 본 연구에서는 수치지도와 각종 수문지형인자를 입력매개변수로 하는 GIS을 이용하여 토사유실에 대한 영향을 분석함으로써 관개용 저수지 토사유실에 대한 예측의 신뢰도를 높일 수 있는 방안을 마련하는데 그 목적이 있다.

• 한국환경과학회지
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• 제23권7호
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• pp.1321-1332
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• 2014

The key objective of this study was to evaluate trophic state and empirical water quality models along with analysis of fish trophic guilds in relation to water chemistry (N, P). Trophic state index (TSI), based on total phosphorus (TP) and chlorophyll-a (CHL), ranged between oligotrophic and hypereutrophic state, by the criteria of Nurnberg(1996), and was lower than the trophic state of total nitrogen (TN). Trophic relations of Secchi depth (SD), TN, TP, and CHL were compared using an empirical models of premonsoon (Pr), monsoon (Mo), and postmonsoon (Po). The model analysis indicated that the variation in water transparency of Secchi depth (SD) was largely accounted (p < 0.001, range of $R^2$ : 0.76-0.80) by TP during the seasons of Mo and Po and that the variation of CHL was accounted (p < 0.001, $R^2=0.70$) up to 70% by TP during the Po season. The eutrophication tendency, based on the $TSI_{TP}$ vs. $TSI_{N:P}$ were predictable ($R^2$ ranged 0.85-0.90, p < 0.001), slope and y intercept indicated low seasonal variability. In the mean time, $TSI_{N:P}$ vs. $TSI_{CHL}$ had a monsoon seasonality in relation to values of $TSI_{N:P}$ during the monsoon season due to a dilution of reservoir waters by strong monsoon rainfall. Trophic compositions of reservoir fish reflected ambient contents of TN, TP, and CHL in the reservoir waters. Thus, the proportions of omnivore fish increased with greater trophic conditions of TP, TN and CHL and the proportions of insectivore fish decreased with greater trophic conditions.

• Advances in environmental research
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• 제5권3호
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• pp.153-167
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• 2016

We applied multilayer perceptron (MLP) and radial basis function (RBF) neural network in upstream and downstream water quality stations of the Karaj Reservoir in Iran. For both neural networks, inputs were pH, turbidity, temperature, chlorophyll-a, biochemical oxygen demand (BOD) and nitrate, and the output was dissolved oxygen (DO). We used an MLP neural network with two hidden layers, for upstream station 15 and 33 neurons in the first and second layers respectively, and for the downstream station, 16 and 21 neurons in the first and second hidden layer were used which had minimum amount of errors. For learning process 6-fold cross validation were applied to avoid over fitting. The best results acquired from RBF model, in which the mean bias error (MBE) and root mean squared error (RMSE) were 0.063 and 0.10 for the upstream station. The MBE and RSME were 0.0126 and 0.099 for the downstream station. The coefficient of determination ($R^2$) between the observed data and the predicted data for upstream and downstream stations in the MLP was 0.801 and 0.904, respectively, and in the RBF network were 0.962 and 0.97, respectively. The MLP neural network had acceptable results; however, the results of RBF network were more accurate. A sensitivity analysis for the MLP neural network indicated that temperature was the first parameter, pH the second and nitrate was the last factor affecting the prediction of DO concentrations. The results proved the workability and accuracy of the RBF model in the prediction of the DO.

• 지구물리와물리탐사
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• 제26권4호
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• pp.199-210
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• 2023

CO₂ 주입 후 저류층은 암석물리 특성이 변하므로 이 연구에서는 저류층을 물성이 선형으로 변하는 전이대 지층모델로 구성한다. 울프 반사계수 함수는 전이대 상하지층의 속도비, 주파수, 전이대 두께 함수로 구성되어 있어 저류층 두께나 해저면 전이대 두께를 추정하는데 활용할 수 있다. 이 연구에서는 심층학습을 이용하여 전이대 두께를 예측 방법을 제안한다. 심층학습을 적용하기 위해 사암 저류층, 셰일 덮개암으로 구성한 인공 전이대 지층모델에 두께에 따른 울프 반사계수 모델링을 수행하고 시간-스펙트럼 영상자료를 확보하였다. 두께별 시간-주파수 스펙트럼 영상과 중합단면도 트레이스에서 구한 시간-주파수 스펙트럼 비교로부터 구한 두께 추정결과는 항상 정확하게 전이대의 두께를 제시하지는 못하였다. 그러나 다양한 환경에서 학습자료를 확보하고 정확도를 높이면 현장자료적용이 가능할 것으로 본다.

• 생태와환경
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• 제56권2호
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• pp.127-139
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• 2023

대청호는 유역에 있는 비점오염원으로부터 유입되는 오염물질로 인해 남조류 과다증식에 기인한 녹조가 빈번하게 발생하고 있다. 이에 녹조 관리 대책 중 하나로 인공습지를 설치하여 호소에 유입되는 오염물질을 저감하고 있다. 본 연구에서는 비점오염원의 관리방법으로 인공습지의 적용 가능성을 평가하기 위해 대청호 상류에 설치된 서화천 생태습지를 대상으로 2014년부터 2020년까지 유입수 및 유출수의 BOD, COD, SS, T-N, T-P 등 오염물질 농도를 분석하였다. 분석 결과 대체적으로 인공습지에서의 처리를 통해 오염물질의 농도가 감소하는 것이 확인되었으며, 특히, 유기물질보다 질소, 인과 같은 영양염류에 있어 높은 처리효율이 확인되었다. 유입수의 오염물질 농도에 따른 처리효율을 구간을 나누어 분석한 결과 대체적으로 고농도에서 처리효율이 높은 경향을 나타내었다. 설치 및 운영 경과에 따른 연도별 인공습지 처리효율을 분석한 결과, T-P에서 큰 변화가 확인되었다. 이는 인공습지 조성 초기에는 식생의 성장에 따라 높은 처리효율을 보였지만, 식생이 안정화되고 습지 퇴적층이 포화됨에 따라 처리효율이 점진적으로 감소한 결과로 판단된다. 본 연구의 결과는 초기 강우 등 높은 농도의 오염물질 유입 및 주기적인 퇴적토 준설 등의 관리가 이루어진다면 인공습지가 유역면적이 넓고, 비점오염원의 영향을 크게 받는 댐 저수지의 부영양화 억제에 유용한 수단이 될 수 있음을 보여준다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.85-92
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• 2002

When the United Nation classified as Korea is the one of the water deficit country. The consensus was made that the water is the one of the precious national resources. Government increases their R/D budget trying to get more clean water bodies. For instances, 'Sustainable Water Resources Development' project is the one of major title in '21 Century Frontier Research project and there are several small research projects are undergoing by the Ministry of Agriculture and KARICO. However, when the environmental preservation issue has been get more emphasis, construction of the Surface Dam met the blockage from the environmentalists due to the problem of the their water buried area. Since the most fitting site for surface dam had been used in the past, some engineer move their focus on modification of the existing Dam's height to enlarge its capacity or dredging the bottom of the reservoir recently However dredging evoke water quality problem in return by accumulated materials at the bottom. Last year the Dong Gang Dam plan has been canceled by environmental problem in water buried area of the reservoir. With the point of this view, ground water gets more focus for the one of the useful alternative for clean water bodies. Underground dam technique which had widely applied once in the early nineteen eighties by the KARICO and attenuated due to engineering insufficiency. The technique is newly studied with the advanced engineering technique. Still groundwater usage rate in Korea is much lower comparing with the advanced countries and has many rooms to develop. Wells, under ground dam and radial collector wells are typical facilities up to now. There is little application in Korea for the Recharge Dam, which had been widely used in the advanced countries. The Recharge Dam is technique to conjunct surface water and groundwater body together, This technique had developed to increase groundwater recharge at the beginning This research is the result of the study on the possibility of the development of the new technology, Groundwater Reservoir' which was modified from Recharge Dam. Groundwater Reservoir is like a deep artificial lakes trenched in hard rock aquifer to get groundwater. The advantage of the Groundwater Reservoir is followings 1) It can be developed at the plains area, not in the deep valley 2) Huge water body can be developed without dam 3) Small buried area comparing surface water dam makes the least environmental effect. 4) Trenching cost can be substitute by the income of the selling rock debris 5) Outfit of the reservoir can be modified to match with the site prospect 6) Rock debris can be used as constructing materials 7) It can be used as groundwater recharge system when the heavy rains comes 8) The reservoir looks like scenery lake with huge clean water bodies.