• Proceedings of the Korea Water Resources Association Conference
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• 1999.05a
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• pp.463-468
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• 1999

• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1051-1057
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• 2002

• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1105-1110
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• 2002

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.134-143
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• 2002

우리나라의 경우 항만 및 어항의 개발시 항내의 정온 및 가동률 확보를 위해서 설치되는 방파제 등 외곽시설이 외해로부터의 침입파랑을 효과적으로 차단하고 있으나 한편으로는 이러한 구조물이 해수에 대하여 비투과성이므로 항만의 폐쇄성을 증대시켜 해수순환성이 저하되어 항만 수질오염이 악화되는 경향이 있다. 일반적으로 비투과성 방파제가 설치되면 항내 외간의 해수교환력이 떨어져서 오염물질 등이 항내에 머무르는 시간이 길어지므로 항내의 오염이 가속될 뿐만 아니라 오염원에 포함됨 유기물이 분해됨에 따라 항내 해수의 용존산소가 다량 소모되어 빈 산소상태를 야기시켜 항내의 수질에 부정적인 영향을 미친다. (중략)

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.4
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• pp.385-398
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• 2007

It was analysed that spatial and temporal change patterns of general water quality constituents were measured monthly from 2002 to 2005 in Jumunjin Harbour. The measured constituents are temperature, salinity, pH, SS and DO. Concentration difference of upper lower layer for general water quality constituents was small. Temperature and DO concentration show the clear difference at temporal concentration change pattern, but SS, pH and salinity have irregular change pattern. Also, water quality improvement effect of seawater exchange facilities and sewage treatment plants is analysed quantitatively using averaged spatial and temporal data set. From this result, it is found that effect of sewage treatment plants is small and seawater exchange facilities at zone 1 and 2 is clear concentration reduction effect to be about 26% and 16%, respectively. After sewage treatment plants operation, DO concentration reduced about 10% at inner zone of Jumunjin Harbour, the other side, after seawater exchange facilities concentration DO concentration increased about 10%. DO concentration at 2005 estimated little than that of 2002, it is concluded that a yearly change of DO concentration has about 10%.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.2
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• pp.109-121
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• 2001

This paper describes results of an experimental study to examine the effect of a submerged horizontal breakwater to sea water exchange. Flow measurements were taken by using a PIV(Particie Image Velocimetry) system, and mean currents and wave ellipses extracted through the harmonic analysis are presented. As results, the rates of circulating flow were closely connected with the volume flux of incident waves and the counter-rotating vortex pair was observed at the onshore side of a plate. The dye study showed that incoming sea water and polluted water body mixed up significantly due to turbulent motions induced by a jet-like flow.

• Resources Recycling
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• v.33 no.2
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• pp.16-23
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• 2024

The electrolysis for extracting magnesium from seawater or brine primarily involves recovery of magnesium via precipitation as the form of magnesium hydroxide. The technology is classified into cation-exchange membranes (CEM), anion-exchange (AEM) membranes, electrodialysis, and membraneless methods. Recent research has focused on enhancing the efficiency and selectivity of magnesium recovery from seawater or brine containing magnesium, with expectations of effective magnesium recovery even with normal seawater. In a future, the optimization of the selective and efficient recovery of magnesium and various valuable substances through long-term operation of scaled-up systems is crucial with enhancing economic and environmental viability. It is essential to realistically estimate operational costs considering the membrane's lifespan and replacement cycle. Also, detailed and practical process models should be developed based on monitoring data on various factors.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.523-526
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• 2005

방조제 건설로 형성된 호소의 수질악화가 중요한 사안으로 대두되면서 수질개선을 위한 다양한 대안이 제안$\cdot$시행되고 있다. 호소 및 연안 수질개선에 대한 근본적인 대책의 일환으로 유입 오염부하량(pollutants loads) 삭감 측면에서는 환경기초시설(하수종말처리장 등) 건설사업이 계획$\cdot$추진되고 있다. 반면, 유역의 오염부하량 삭감계획과 병행하여 수문개방에 의한 청정한 외해수 유입에 의한 해수유통으로 수질개선을 도모하는 경우도 있다. 시화호 수질보전대책의 일환으로 수문개방을 통한 외해수 유입은 1997년 이후 지속적으로 시행되고 있으며, 2002년 3월 최종 끝물막이 공사가 완료된 화옹지구 방조제 공사로 형성된 화옹호도 2007년 담수화 개시 이전까지 수질보전대책의 일환으로 수문(배수갑문) 개방을 통한 해수유통을 계획하고 있는 실정이며, 충청남도에 위치한 홍성$\cdot$보령방조제도 수문개방에 의한 해수유통을 실시하고 있다. 또한, 시화호 관리기관인 한국수자원공사에서는 세계 최대규모의 조력발전소 건설을 통한 발전 및 발전소를 통과하는 외해수 유입$\cdot$유출에 의한 수질개선계획을 추진하고 있다. 그러나, 수문개방 또는 인공구조물을 통한 외해수의 유입$\cdot$유출에 의한 수질개선효과는 인위적인 요소와 자연적인 요소, 장기적인 변화 및 단기적인 변화가 결합되어 매우 복잡한 양상을 보일 수 있기 때문에 체계적인 분석을 통하여 수질개선효과를 검토하여야 한다. 본 연구에서는 현재 진행되고 있는 시화호 배수갑문 운영양상을 기준으로 하여 배수갑문 운영에 대한 외해수의 유입$\cdot$유출에 의한 수질변화양상을 단계적으로 구분하여 수질변화에 중요한 영향을 미치는 인자에 대한 이론적인 분석을 수행하고, 배수갑문 개방에 의한 수질개선효과를 최대화하기 위한 환경관리 방안 제시에 중점을 두어 수행하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.30-34
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• 1988

In roastal fish farms the farmers, especialy engaging in dealing with the floating cage culture, going to know about relationships between holding capacity and water quality in cage. Some of water quality managers and specialists studing physiological ecology understand that the key of water quality management concerned fish farming is budget of dissolved oxygen. This paper deals with oxygen budget in floating cage of the yellow tail farms at southern coastal area in Korea. The sampling station is located at Konli-Do fish farm near Chungmu, and the data is collected for 24 hours from 3:00 p.m. 8th September 1987. In result, the needed oxygen coming after the consumption by the rearing fish had been supplied with the tide current exchange, the sum of oxygen produced by phytoplankton photosynthesis and diffused from atmosphere are no more that $43\%$ for the needs of sea water consumption included respiration of planktons and decomposition of organic matters. The optimum holding capacity of cage is possible to compute with the calculation of minimum diurnal water exchange rate $[Qin{\cdot}V^{-1}\;(C-\bar{c})]$ through net mesh of cage.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.311-320
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• 1998

The volume transport and turnover time of the Deukryang Bay. located at the southern area of Korea, were calculated based on the current meter(RCM-7,ACM 16M) data observed at the three gateways of the tegrating observed data and then averaging on time. dangdo and Kogumdo. The total water volume transports through three entrances of the bay in May and October were $3.9{\times}10-2Sv, 3.4{\times}10^{-2}Sv(1Sv=10^6m^3s^{-1}$) and turnover time were 0.97day, 1.12day, respectively. Semidiurnal tides were predominant (70~85%). The water volume transports by residual currents were 2~4% of total water volume transports . The average fraction of fresh water calculated by tidal prism method using salinity difference between inflow current and outflow current through three entrances In Deukryang Bay was about 0.06% of total volume and the flushing time of fresh water was estimated as 0.97day.