• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권1호
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• pp.33-39
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• 1999

A two-dimensional numerical experiment and field observations were conducted to evaluate changes in sea water movement and the water quality environment related to comprehensive projects of waterfront development around Kwangyang Bay on the south coast of Korea. Tidal flow velocities, especially in the western part of the bay, were considerably slower as a result of the development projects. Accordingly, the seawater exchange ratio reduced from 38.7% to 26.3%. The impact of dredging work on the water quality environment was much stronger than expected. Furthermore, after the completion of the industrial parks and container-exclusive wharfs, COD from the waste water treatment plant will be dispersed extensively into the adjacent water at a level of less than 0.1 mg/l for up to 142.5 $\textrm{km}^2$. Therefore, consistent monitoring and management of the water quality environment is strongly recommended.

• 상하수도학회지
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• 제30권1호
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• pp.9-17
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• 2016

Disinfectant/oxidation process is a crucial process in water treatment for supplying safe drinking water. Chlorination is still widely used for water treatment area due to its effectiveness on microbial inactivation and economic feasibility. Recently, disinfection concern in marine environment is increasing, for example, movement of hazardous marine organism due to ballast water, marine environmental degradation due to power plant cooling water discharge, and increase of the amount of disinfectant in the offshore plant. It is needed to conduct the assessment of disinfectant behavior and the development of disinfectant prediction model in seawater. The appropriate prediction model for disinfectant behavior is not yet provided. The objective of the study is to develop chlorine decay model in seawater. Various model types were applied to develop the seawater chlorine decay model, such as first order decay model, EPA model, and two-phase model. The model simulation indicated that chlorine decay in seawater is influenced by both organic and inorganic matter in seawater. While inorganic matter has a negative correlation with the chlorine decay, organic matter has a positive correlation with the chlorine decay.

• 지질공학
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• 제13권1호
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• pp.17-27
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• 2003

본 연구에서는 해수침투에 관한 기존 이론을 검증하고 지하수 함양량과 양수량의 변화에 따른 담-염수 경계면 이동현상을 고찰하기 위하여 실내 모형규모의 자유면 대수층에서 시간 영역 광전자파 분석기 (Time Domain Reflectometry: TDR)를 이용하여 2차원 염수침투 현상을 관측하였다. 실험 결과 염수와 담수의 경계면에서는 분산 혹은 확산에 의한 혼합대 (mixing zone)가 두텁게 형성되었으며 Badon Ghyben과 Herzberg가 가정한 비혼합 경계면 (sharp interface)은 형성되지 않았다. 따라서 본 연구에서 획득한 기준 해수면에 대한 자유수면($H_{f}$)과 염수 경계면($H_{s}$)까지의 깊이의 비에 관한 실험치와 Ghyben-Herzberg 근사법의 이론치가 일치하지 않음을 알 수 있었다. 한편, 함양량과 양수량을 달리하면서 경계면의 변화를 관찰한 결과 주어진 함양량에 대하여 양수량이 증가함에 따라 경계면의 이동속도가 증가하였고, 본 모형조건하에서 경계면의 이동속도는 함양량에 대한 양수량의 비 ($Q_{p}/Q_{r}$)에 약 7배나 달하는 것으로 나타났으며 이는 해안선에 인접한 해수 침투 취약지역에서는 양수량이 아주 중요한 역할을 한다는 것을 지시한다.

• 한국해양학회지:바다
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• 제26권1호
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• pp.1-10
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• 2021

최근 10년(2009년~2018년)간의 해수범람 기록정보와 해양 및 해양기상 관측정보를 수집하고 기계학습 알고리즘을 3종을 종합·활용해 해수범람 유형과 유형별 관측정보의 특징을 분류하였다. 해수범람의 기록정보는 국립해양조사원의 침수조사 보고서와 국토정보공사의 침수흔적도를 통해 수집하였으며 해양 및 해양기상관측 정보는 국립해양조사원과 기상청의 부이, 관측소 정보를 수집하였다. 해수범람 발생 유형 분류는 크게 4개의 유형으로 분류되며 4개의 유형의 조합을 통해 5개의 발생 유형으로 분류하였다. 이 유형은 해양기상 환경에 따라 해수범람의 발생 유형을 구분할 수 있었다. 유형별 주요 특징은 대조기, 저기압, 강풍, 태풍으로 구분되었다. 또한, 지리적인 해양특성을 고려하여 지역 및 유형별 해수범람 발생 판단을 위한 해양요소 임계치를 도출하였다.

• 한국농공학회지
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• 제39권6호
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• pp.88-98
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• 1997

In this study, pumping capacity in the area of natural river estuary is estimated by the quantitative analysis using finite element method. The study area is Iga-ri pumping station in the estuary of Seojung-chun which runs to the East coast. First of aH, hydraulic properties and effects of different seawater levels are analyzed in this area. Variations of groundwater level caused by pumping and properties of seawater intrusion are analyzed, then compared the case of reinforcing the existing intake weir with the case of setting up an weir at the upper stream. The observed data of groundwater drawdown caused by pumping during drought period and seawater intrusion are compared with results of the analysis done by groundwater model using finite element method, and it is found that both are similar. Accordingly, groundwater model used in this study reflects well the variation of groundwater level caused by pumping.

• 해양환경안전학회지
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• 제23권1호
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• pp.83-90
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• 2017

본 연구는 해수유동모델을 이용하여 하계 한국 남해안 양식장 부근에서 수온의 시 공간적인 분포를 파악하였다. 한국 남해 조류의 흐름은 창조시 서향, 낙조시 동향하며, 쓰시마 난류의 흐름은 50 m보다 깊어지는 외양에서 연안에 비해 강하게 동북향 하였다. 조류, 바람, 쓰시마 난류 및 실시간 수온을 고려한 해수유동에서 하계 수온의 분포는 반폐쇄성 해역에서 $26{\sim}28^{\circ}C$로 높게 나타났으며, 외양으로 갈수록 낮아져 $18{\sim}22^{\circ}C$로 나타났다. 반폐쇄성 내만의 형태를 가지는 해역의 해수교환량을 계산한 결과 광양만 $10,331m^3/sec$, 여수-가막만 $16,935m^3/sec$, 그리고 거제-한산만은 $13,454m^3/sec$로 나타났다. 해수교환량이 적은 해역일수록 수온이 비교적 높게 나타난다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.158-159
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• 2005

This study showed that the highest temperature point of the Dongrae thermal spring in Pusan was moved to the north direction of the Dongrae fault as times goes by. The Br concentration(1.5mg/L) in Dongrae thermal waters indicated the influence of 2% seawater mixing. If the simple mixing without hydrochemical reaction occurs between seawater and thermal water, the concentration of Mg will be about 20mg/L. But the low concentration(0.1 mg/L) of Mg, contrary to high concentration(10 mg/L) of surrounding groundwater not affected by thermal water, suggested the thermal water, seawater and rock interactions. The calculation of saturation index(SI) by using the geochemical code of EQ3NR showed that the Mg in thermal groundwater, which was introduced by seawater, was removed by the precipitation of Antigorite (SI: log Q/K =71.753, $Mg_{48}Si_{24}O_{85}(OH)_{62}$) and Tremolite (SI: 8.463, $Ca_2Mg_5Si_8O_{22}(OH)_2$), Talc (SI: 6.409, $Mg_3Si_4O_{10}(OH)_2$), Dolomite (SI: 2.014, $CaMg(CO_3)_2$), Chrysotile (SI: 3.698, $Mg_3Si_2O_5(OH)_4$) in the crack of fault zone. The highest temperature point in the study area will move to north direction and stop in the Jangjun area without the input of seawater.

• 한국해양공학회지
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• 제18권5호
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• pp.22-28
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• 2004

This study constructed a 3D real-time numerical model that predicts the water quality and movement characteristics of the inner bay, considering the characteristics of the wind-driven current and density current in estuaries, generated by the river discharge from the Hyeong-san river and oceanic water of the Eastern sea. The numerical model successfully calculated the seawater circulation current of Yeong-il Bay, using the input conditions oj the real-time tidal current, river discharge, and weather conditions during March 2001. This study also observed the wind-driven current and density current in estuaries that are effected by the seawater circulation pattern of the inner bay. We investigated and analyzed each impact factor, and its relationship to the water quality of Yeong-il bay.

• 환경위생공학
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• 제8권1호
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• pp.67-80
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• 1993

This survey was carried out to take the status of seawater intrusion into groundwater wells located in the eastern area of Chejudo, to get the elementary data which may evaluate the level of would-be groundwater contamination, and to perform effective the effort that will supply the clear water for the residents. The sampling sites were northeastern districts of Haengwon, Handong, and Sangdo, southeastern districts of Susan, Nansan, and Samdal, and northwestern districts, as reference, of Aewol, Keumnung, Panpo, Kosan, Shindo, and Bosung. We collected the samples from the public tap water by month, and analysed electrical conductivity, sodium(Na), potassium(K), magnesium(Mg), calcium(Ca), bicarbonate($HC0_{3^-}$), and items of the criteria as drinking water. In the northeastern districts we also added the sampling sites to survey the fluctuations of dissolved solids according to distance from seashore, including two private boreholes and one public tap water of Dukchun. The result is as follows 1) In the northeastern district, the concentration of chloride ion showed large fluctations from 40mg/l to 100mg/l, but suitable for the criteria of drinking water. It was thought that the drought influenced. 2) In the Sangdo of the northeastern districts, similar tendancy to Hangwon and Handong was showed only in the concentration of chloride ion, but different tendancy was showed in chloride-bicarbonate ratio, calcium-magnesium ratio, and sodium adsorption ratio(SAR). Considering these facts, it was not thought that seawater intruded. 3) The components of Na and Cl showed rapid slope in the northeastern districts above 3km from seashore. 4) In the northwestern districts as reference, the concentration of chloride ion fluctuated slightly according to the sampling sites and dates, and the concentration of nitrate-nitrogen in some sites exceeded the criteria of drinking water. These were thought that the surface contaminants rather than the intrusion of seawater influenced mainly the groundwater, considering the correlation(r=0.732) of chloride ion and nitrate-nitrogen. 5) Then we must consider the regional characteristies of soil profile in order to prevent the contamination of groundwater, and moniter also the movement of main components within the sol1 profile, not only the research of the intrusion of seawater.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권5호
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• pp.1-4
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• 2009