• 한국환경과학회지
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• 제14권11호
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• pp.1063-1069
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• 2005

2004년 12월 2일부터 8일까지 한국 남해의 표층 부유물질의 분포를 초겨울의 해황과 관련하여 조사하였다. 쓰시마와 제주도를 잇는 지선을 중심으로 전선이 형성되었으며, 이 전선을 중심으로 한국 남해의 연안수와 외양의 쓰시마난류수로 구분되었다. 연안역은 표층에서 저층까지 거의 균일한 수괴 분포를 보였으며, 외양은 성층이 형성되어 있었다. 그리고 부유물질은 연직혼합된 연안역에서는 5.0-6.5 mg/l였으며, 성층이 형성된 외양역은 4.5-5.0 mg/1의 분포를 나타내었다. 초겨울 한국 남해는 표면 냉각 효과와 바람에 의해서 저층의 부유물질이 충분히 재부유할 수 있는 환경이었음을 나타내고 있었다. 또한 관측 기간동안 비록 조류가 비교적 약한 소조기 이었음에도 불구하고 열플럭스에 의한 냉각효과와 바람에 의한 혼합 효과가 강하여 표층과 저층이 혼합하기에 용이하였음을 나타내었다. 이에 따라 수심이 얕은 연안역에서는 저층 퇴적물의 재부유에 의해서 부유 물질이 증가될 수 있음을 시사하고 있었다.

• 한국컴퓨터정보학회논문지
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• 제28권11호
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• pp.13-20
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• 2023

본 논문에서는 LSTM-Autoencoder 기반 특징추출과 재구성 데이터를 이용한 수온 예측 방법을 제안한다. 냉수대 현상이 발생한 동해 낙산 지역의 해수면 수온과 수온에 영향을 미치는 풍향, 풍속 등 다변량 시계열 데이터를 이용하고, LSTM-Autoencoder 모델을 이용하여, 원본 데이터의 차원 축소를 통해 추출된 특징 데이터를 원본 데이터의 다변수 데이터로 결합한 데이터, 복원 데이터, 원본 데이터 총 3가지를 사용한다. 수온 예측을 위해 LSTM 모델에 3가지 데이터를 학습하고, 정확도를 평가한 결과 MAE 0.3652, RMSE 0.5604, MAPE 3.309%으로 LSTM-Autoencoder의 특징추출을 이용한 수온 예측 정확도가 가장 우수한 성능을 보이는 것을 확인하였다. 본 연구의 결과는 냉수대와 같이 해수면 수온 변화가 급변하는 구간의 예측 정확도를 높여, 자연재해의 피해를 예방할 수 있을 것으로 기대한다.

• 한국수산과학회지
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• 제52권4호
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• pp.400-407
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• 2019

The optimum growth temperature of sea cucumber is $18^{\circ}C$, above $20^{\circ}C$, the appetite declines and the digestive tract is atrophied. At $25^{\circ}C$ or more, it is known that the digestive tract is degenerated as growth is stopped by minimizing metabolic activity. Because of these physiological and ecological characteristics, the growth period of sea cucumber Apostichopus japonicus is relatively short in the natural environment of Korea where four seasons are clear. Therefore, maintenance of water temperature in sea cucumber culture is very important. This experiment was conducted to investigate the growth and lipid compositions of sea cucumbers at high temperature. Results showed that the growth and survival rates of sea cucumber were not significantly different until $26^{\circ}C$ (P>0.01). The fatty acid compositions of total lipid of sea cucumber tended to increase with saturated fatty acid content and decrease with n-3 fatty acid content at higher water temperature.

• Ocean and Polar Research
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• 제30권4호
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• pp.373-378
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• 2008

Long-term tide-gauge data from around the Korean Peninsula were reanalyzed. Both the coastal water and the open sea surrounding the Korean Peninsula appeared to have been influenced by global warming. The long-term change in relative sea levels obtained from tidal stations showed a general rising trend, especially near Jeju Island. It is proposed that global warming may have caused shifting of the path of the Kuroshio branch (Tsushima Warm Current) toward Jeju Island, causing a persistent increase in the water levels along the coast of the island over the last few decades.

• 대한화학회지
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• 제51권4호
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• pp.305-311
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• 2007

정류상태(steady state)와 과도상태(transient state)의 Tafel 기울기, 순환 전압-전류 곡선, 임피던스 측정자료에 기초하여 인공해수에서 구리의 부식과 부동화에 대한 반응 메커니즘을 제안하였다. 구리의 산화환원 반응은 인공해수에서의 산소농도와 전극전위에 의존함을 알 수 있었다.

• 한국응용과학기술학회지
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• 제28권1호
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• pp.29-34
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• 2011

The sterilization of strain and algae in sea water was studied to see the possibility to apply the redox reaction of metal alloy to meet the international marine organization(IMO) regulation, which was to regulate deballasting concentration of strain and algae above 99% of sterilization. Two different kinds of brass were heat treated at different temperature and cooled rapidly to conserve the specific character of ${\beta}$ brass. Untreated Muntz metal showed the best result of antimicrobial rate in sea water, and 7:3 brass showed similar result to Muntz metal. Heavy metal elution rate was inversely proportional to the sterilization capability.

• 대한화학회지
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• 제9권1호
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• pp.49-54
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• 1965

One of the difficult and time consuming problems in the production of magnesia from sea water is a settling rate of magnesium hydroxide. In this experiments, authors attempted to accelerate its settling rate by addition of various sedimenting agents as C.M.C., Separan and Starch, and sought for optimum calcination temperature for domestic dolomite, as alkali source, mole ratio of dolomite milk to bittern. It is observed through experiments that the small amounts of sedimenting agents, C.M.C., Separan, starch, 20 mg/l, 40 mg/l, 400mg/l, respectively increase the settling rate of magnesium hydroxide by 8 times or more. The following conditions resulted in good yield of magnesium hydroxide from sea water with relatively tolerable calcium oxide contaminated for the magnesium clinker. Calcinating temperature, $1,100{\sim}1,200^{\circ}C$, mole ratio of 10% dolomite milk to magnesium salts in sea water or bittern, 1. 2 : 1.

• 한국해양학회지
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• 제15권1호
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• pp.66-70
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• 1980

A method for the determination of dissolved species of Cd, Co, Cu, Ni, Pb and Zn in sea water by flame atomic absorption spectrophotometry (AAS) is described. Prior to analysis by AAS, these elements are concentrated by coprecipitation with iron pyrrolidinedithiocarbamate at pH 3 because of matrix effects and their low concentration levels in sea water. The detection limits are 0.01, 0.04, 0.02, 0.05, 0.08, and 0.03$\mu\textrm{g}$/l, and the relative standard deviations are 1.0, 2.4, 1.3, 2.9, 2.0 and 2.9% for Cd, Co, Cu, Ni, Pb and Zn, respectively. The method is shown to be satisfactory in terms of recovery and precision for the determination of these metals in sea water.

• 한국농공학회논문집
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• 제56권6호
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• pp.159-167
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• 2014

In this study the process of normalizing hydraulic head loss rate was developed for the purpose of estimation of seepage blocking state at each seepage segment in sea dike embankment. Pore water pressure sensors were installed with some interval along seepage path, then the hydraulic head loss rate at each segment between pore water pressure sensors was calculated, and then the calculated hydraulic head loss rate was normalized based on seepage path length. The comparison of normalized hydraulic head loss rates showed that the cross section of sea dike embankment was homogeneous approximately and the width of cross section was long enough to blocking tide water.

• 분석과학
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• 제11권6호
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• pp.499-504
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• 1998

An analytical method for the simultaneous measurement of trace Cu, Sn, and Bi in sea water has been investigated by Inductively Coupled Plasma-Mass Spectrometry. Amberlite IRC-718 resin was used as a solid phase in solid-liquid extraction technique for the removal of matrix interferences such as Na, S, P, and other polyatomic ion species. Recoveries of 99.8% for Cu, 99.6% for Sn, and 97.9% for Bi were obtained for the standard spiked sample. The developed method was applied to analysis of trace metals in sea water.