• 대한안전경영과학회지
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• 제17권1호
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• pp.149-168
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• 2015

It is expected that the temperature in Pyeongyang will be similar to that ($16.6^{\circ}C$) in Seogwipo in the late 21st century, and most of South Korea will enter the subtropical climate due to climate change. Change in the precipitation pattern like the range of fluctuation caused by climate change will lead to expanded uncertainty in securing reliable water supply, along with a serious impact on demands for living and industrial water due to change in the volume and period of river outflow. As industrial water for production activities is estimated based on the contract quantity, it is difficult to apply rationalization of water usage and incentives in water recycling. Therefore many companies are making efforts in complying with the effluent standard while spending few resources on such rationalization and recycling. This study researched water risk management over 115 Korean companies by 28 questions in 4 categories. Through the research, this study aims to understand water risk management levels and seek response plans.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.2122-2126
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• 2008

With the degradation of water quality and, at the same time increased water usage, the sources of high quality, for examples, river/stream, municipal reservoir, wells, artisan and surface water, are diminishing. Therefore, the importance of water quality has been emphasized over the years through publications and various literature sources. Even though considerable research has resulted in significant strides for providing interpretive information and mitigation strategies for improvement of waters, the quality of which is still questionable. This study aims to propose a completely independent self-contained system for purifying waters, solar-powered ozone generator. It is a semi-permanent and cost effective environmental solution. Functions of ozone treatment are: 1) to maintain oxidative flexibility, 2) remove harmful chemicals, wastes, and other substances, and 3) prevent epizootic microbial outbreaks. Recent advances in technology have allowed the development of the practical, self-contained and independent solar powered device. Solar electrical producing panels that charge batteries are the key to using these systems anywhere electrical power is not available. This paper invites the readers to examine the problem and consider the viable, proven solution the solar powered ozone purifying system. This paper also introduces basic concept and background of solar powered ozone generators and examine its feasibility for improving water quality in rivers and streams.

• 한국수자원학회논문집
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• 제55권7호
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• pp.531-543
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• 2022

최근 국내에서는 수량, 수질 등 기후변화로 인한 다양한 수자원 문제에 효율적으로 대응하기 위한 통합물관리 체계가 점차 고도화되고 있으며, 특히 친환경적인 관점에서 이미 개발된 수자원시설물의 탄력적인 활용 방안이 주목받고 있다. 이처럼 용수를 사전에 확보하고, 적시에 공급하기 위한 대표적인 수자원 관리 시설로 다목적댐, 용수전용댐 등이 가장 잘 알려져 있으나, 지난 2021년 '한강수계 발전용댐 다목적 활용 협약'을 기점으로 발전용댐 또한 기존의 수력발전 용도를 넘어 수자원 관리 기여도가 한층 높아지게 되었다. 댐에서는 가뭄 발생시 구체적인 가뭄단계 파악 및 용수공급량 조절을 통해 용수공급을 조절해야 한다. 이미 다목적댐 및 용수전용댐의 경우 가뭄대응을 위한 용수공급 운영기준이 마련되어 적용 중에 있으나, 최근에 다목적 활용이 추진된 발전용댐의 경우 구체적인 관련 기준이 마련되어 있지 않은 실정이다. 본 연구에서는 기존 다목적댐 및 용수전용댐 운영기준을 참고하여, 발전용댐의 가뭄단계별 기준저수량 산정 방안 및 용수공급 조정 방안 등을 제시하였다. 제시된 방법은 국내 대부분의 발전용댐이 위치한 한강수계 발전용댐을 대상으로 적용하였으며, 지난 2014~2017년 발생한 가뭄사례를 바탕으로 그 적용 효과를 분석한 결과, 대상 발전용댐의 용수공급 안정성이 개선되는 효과를 확인하였다. 수자원의 효율적인 이용을 위한 발전용댐의 역할은 점차 중요해질 것으로 예상되며, 본 연구 결과는 발전용댐을 활용한 용수공급 관련 연구에 폭넓게 활용될 수 있을 것으로 기대된다.

• 환경영향평가
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• 제20권5호
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• pp.765-777
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• 2011

According to the total pollution load management system, exact prediction and analysis of water quality and discharge has been required in order to allocate the amount of pollution load to each local government. In this study, QUAL2E model was used for comparison with other water quality models and improve the inadequate to forecast future water quality. And Various calibration and verification methods were applied to deal with existing uncertainties of parameter during modeling water quality. For user convenience, A GUI(Graphical User Interface) system named "QL2-XP" model is developed by object-oriented language for the user convenience and practical usage. Suggested GUI system consist of hydraulic analysis, water quality analysis, optimized model calibration processes, and postprocessing the simulation results. Therefore this model will be effectively utilized to manage practical and efficient water quality.

• 한국환경농학회지
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• 제23권1호
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• pp.41-46
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• 2004

하천 수질관리 대안을 제시하고자 동진강에 영향을 가장 크게 미치는 정읍천을 대상으로 2002년 1월부터 2003년 12월까지 점 및 비점 오염원으로부터 수질오염물질의 부하량, 유출경로 등을 평가하였다. 계절별 수질 변화는 pH범위가 $6.87{\sim}7.53$으로 봄의 pH 범위가 컸으며, EC 농도는 정읍천 중류가 높았으며, 상류유역은 $83{\sim}95\;{\mu}s/cm$ 범위를 나타냈고, 계절별로 가을에 $517\;{\mu}/cm$로 가장 높았다. BOD의 농도는 상류유역에서 $0.61{\sim}1.27\;mg/L$로 I 급수 수질을 나타내었으나, 중류와 하류에서는 III등급 수준이었다. T-N의 농도는 정읍천 중류 유역이 $6.10{\sim}10.84\;mg/L$로 가장 높았고, T-P의 농도는 타 오염물질에 비해 농도의 편차가 컸으며, 특히 중류에서 T-P의 농도가 $0.41{\sim}0.98\;mg/L$로 높았다. BOD의 배출부하량은 J4 유역에서 553 kg/day로 가장 많았고 T-N 발생부하량은 가축, 인구, 토지이용, 산업의 순으로 켰으며, T-N 배출부하량은 인구 및 산업에 의한 것은 J4 유역, 가축과 토지이용에 의한 부하량은 J5, J6유역에서 높았다. T-N의 유달부하량은 하류 유역에서 높았으며, T-P의 유달 부하량은 BOD, T-N에 비하여 유달부하량이 낮았고 유달율은 $6{\sim}38%$ 범위를 나타냈다.

• 한국물환경학회지
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• 제26권5호
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• pp.761-767
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• 2010

This study introduces a model of territorial analysis on Chungcheongnam-do Nonsan-chun valley area, which gives an example of a method of selecting the management area for non-point pollution source from land use to help eliminate its source. High discharge load per unit area signify high level of land ratio with high level of basic unit of development load (including factory sites, school sites, roadways), which mean that there are a significant level of urbanization. It is these areas with the examination of the water quality of the nearby river that should be considered as the management area for non-point pollution source. Thus, the management area for non-point pollution source should be sought in areas with high discharge load per unit area and high density of water pollution area. When level of drainage is high the pollution density level is relatively lower, and when the level of drainage is low the density level is relatively higher. The level of pollution from non-point pollution source is much lower with more water flowing through. The possible non-point pollution source areas that were selected with these standards were then examined with the distance from the river, the slope angle, land usage, elevation, BOD discharge density load, T-N discharge density load, T-P discharge density load, and were given a level one through five. Out of the possible areas Nonsan-si Yeonmu-eup Anshim-li was the densest area, and it was given level one. The level one area should be examined further with the field analysis to be selected as the actual management area for non-point pollution source.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.2043-2047
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• 2009

국내 하천의 홍수터는 농경지, 공원 및 주차장 등으로 도시는 물론 농촌에서까지 다양하게 활용되고 있음에도 불구하고 과거 오랜기간동안 무분별하게 점용허가되거나 불법으로 점용 및 활용되면서 홍수터 활용 실태가 파악되어 있지 못한 실정이다. 또한, 2007년 하천법 개정을 통하여 하천의 친환경적인 관리를 위하여 보전지구, 복원지구 및 친수지구로 구분하여 하천을 관리할 계획을 가지고 있으나 현재 하천에 대한 전반적인 조사가 부족하여 구분할 근거나 방법이 없는 실정이다. 따라서 본 연구에서는 국내 주요하천에 대하여 홍수터의 활용 현황을 조사 및 분석하여 문제점과 대책방향을 제시하고자 한다.

• 한국토양비료학회지
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• 제32권3호
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• pp.223-231
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• 1999

1. 만경강 수계 수질변화 만경강 수계의 농업용수의 수질 변화를 조사 분석하기 위해 '94, '95년, '97년도 4월에서 9월까지 13개지점을 대상으로 평가하였다. $NH_4-N$, $SO{_4}^{2-}$, $Cl^-$의 농도는 4월에 가장 높았으며 $NO_3-N$는 8월에 높았다. COD 함량은 고온기인 9월에 높게 나타났다. 만경강 주요지천중 $NH_4-N$와 $SO{_4}^{2-}$ 이온이 농업용수 기준을 초과하였으며, 만경강 중류(Mk-8), 고산천(Mk-9) 그리고 소양천(Mk-11)을 제외하고는 만경강 주요 지천은 농업용수로서 부적당하였다. 만경강 하류(Mk-2, Mk-3)와 전주천(Mk-12) 그리고 삼천천(Mk-13)은 도시생활하수와 산업 폐수에 의해 오염도가 높았으며, 익산천(Mk-6)은 양돈 오수에 의해 오염도가 증가되었다. 만경강의 이온들의 당량합은 산업폐수와 생활하수가 다량 유입되는 만경강 하류인 유천 갑문(Mk-3)이 가장 높았으며 음이온의 당량은 $SO{_4}^{2-}$, $Cl^-$, $NO{_3}^-$, $PO{_4}^{3-}$ 순으로 많았고 양이온은 $Na^+$, $Ca^{2+}$, $NH{_4}^+$, $Mg^{2+}$, $K^+$ 순이었다. 2. 시설원예지 지하수중 화학성분 변화 만경강유역 인근에 있는 시설원예 주산단지에서 사용하는 지하수 수질을 '94년부티 '98년까지 지하수심, 조사시기 영농형태, 경작연수별로 검토하였다. 채수수심이 깊어질수록 $NH_4-N$, NO-N함량이 낮아졌으며, $SO{_4}^{2-}$와 $Na^+$는 10~15m 이하에서는 큰 차이가 없었다. 지하수중 $NH_4-N$, $NO_3-N$, $PO{_4}^{3-}$, $SO{_4}^{2-}$, $Na^+$, $Cl^-$ 함량기에 비해 갈수기에 높았다. 시설원예연작에 비해 미나리 윤환재배로 지하수중 $NH_4-N$, $NO_3-N$, $PO{_4}^{3-}$, $Na^+$, $Cl^-$함량이 낮아졌다. 완주군 용진면은 지하수중 $NO_3-N$ 함량이 농업용수 기준을 초과하였고, $SO{_4}^{2-}$ 농도는 완주군 용진면, 완주군 삼례면 지역이 타지역보다 높았고 익산시 석탄 등은 지하수중 $PO{_4}^{3-}$, $Na^+$, $Cl^-$ 함량이 타지역보다 높았다.

• Steel and Composite Structures
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• 제51권2호
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• pp.153-172
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• 2024

Due to the fast development of constructions in recent years, there has been a rapid consumption of fresh water and river sand. In the production of concrete, alternatives such as sea water and sea sand are available. The near surface mounted (NSM) technique is one of the most important methods of strengthening. Aluminum alloy (AA) bars are non-rusting and suitable for usage with sea water and sand concrete (SSC). The goal of this study was to enhance the shear behaviour of SSC-beams strengthened with NSM AA bars. Twenty-four RC beams were cast from fresh water river sand concrete (FRC) and SSC before being tested in four-point flexure. All beams are the same size and have the same internal reinforcement. The major factors are the concrete type (FRC or SSC), the concrete degree (C25 or C50 with compressive strength = 25 and 50 MPa, respectively), the presence of AA bars for strengthening, the direction of AA bar reinforcement (vertical or diagonal), and the AA bar ratio (0, 0.5, 1, 1.25 and 2 %). The beams' failure mechanism, load-displacement response, ultimate capacity, and ductility were investigated. Maximum load and ductility of C25-FRC-specimens with vertical and diagonal AA bar ratios (1%) were 100,174 % and 140, 205.5 % greater, respectively, than a matching control specimen. The ultimate load and ductility of all SSC-beams were 16-28 % and 11.3-87 % greater, respectively, for different AA bar methods than that of FRC-beams. The ultimate load and ductility of C25-SSC-beams vertically strengthened with AA bar ratios were 66.7-172.7 % and 89.6-267.9 % higher than the unstrengthened beam, respectively. When compared to unstrengthened beams, the ultimate load and ductility of C50-SSC-beams vertically reinforced with AA bar ratios rose by 50-120 % and 45.4-336.1 %, respectively. National code proposed formulae were utilized to determine the theoretical load of tested beams and compared to matching experimental results. The predicted theoretical loads were found to be close to the experimental values.

• Environmental Engineering Research
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• 제25권3호
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• pp.267-273
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• 2020

This Hydrokinetic energy system is the process of extracting energy from rivers, canals and others sources to generate small scale electrical energy for decentralized usage. This study investigates the application of Soil and Water Assessment Tool (SWAT) in Geographical Information System (GIS) environment to evaluate the theoretical hydrokinetic energy potentials of selected Rivers (Asa, Awun and Oyun) all in Asa watershed, Kwara state, Nigeria. SWAT was interfaced with an open source GIS system to predict the flow and other hydrological parameters of the sub-basins. The model was calibrated and validated using observed stream flow data. Calibrated flow results were used in conjunction with other parameters to compute the theoretical hydrokinetic energy potentials of the Rivers. Results showed a good correlation between the observed flow and the simulated flow, indicated by ash Sutcliffe Efficiency (NSE) and R² of 0.76 and 0.85, respectively for calibration period, and NSE and R² of 0.70 and 0.74, respectively for the validation period. Also, it was observed that highest potential of 154.82 MW was obtained along River Awun while the lowest potential of 41.63 MW was obtained along River Asa. The energy potentials obtained could be harnessed and deployed to the communities around the watershed for their energy needs.