• Title/Summary/Keyword: red Sea

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Geotechnical Properties of Pelagic Red Clay in Northeast Equatorial Pacific (북동태평양 원양성 적점토의 지질공학적 특성에 관한 연구)

  • Chi, Sang-Bum;Lee, Hyun-Bok;Hyeong, Ki-Seong;Ju, Se-Jong;Lee, Gun-Chang;Ham, Dong-Jin
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.3
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    • pp.286-294
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    • 2008
  • In order to understand the physical properties of deep-sea sediments, which mainly consist of pelagic red clays, sediment samples were collected at 24 stations using a multiple corer in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific. The sampled sediment cores were examined for the mass physical properties(i.e. grain size distribution, mean grain size, water content, specific grain density, wet bulk density, void ratio, and porosity) and the geotechnical properties(i.e. shear strength and consistency limits) with the content of biogenic opal and mineral composition. Although KR1 and KR2 areas on the same latitude are logitudinally far from each other, the mass physical properties of these areas are not distinctly different except for shear strengths. The maximum shear strength of surface sediments in KR2 area is higher than that in KR1 due to the appearance of a consolidated lower layer(Unit 3) in the sediment core from KR2.

Red Tide Algae Recognition using PCA and Roundness (주성분분석과 원형율을 이용한 적조생물 인식)

  • Park, Sun;Lee, Yeon-Woo;Jeong, Min-A;Lee, Seong-Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.11B
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    • pp.1339-1345
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    • 2011
  • Red tide is a natural phenomenon that change sea color by harmful algal blooms. There have been many studies on red tide due to increasing of red tide damage. However, to automatically classify the red tide algae is not enough. Recognition of red tide algae is difficult because they do not have matching center features for recognizing algae image object. Previously studies are used a few type of red tide algae for classification. In this paper, we proposed the red tide algae recognition method using PCA and roundness of image objects.

Characteristics of Meteorological and Marine Environments for the Red Tide Occurrence of Mid-South Sea in Korea (한국 남해중부해역의 적조발생에 관한 기상 및 해양환경 특성)

  • 윤홍주;김승철;박일흠
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.4
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    • pp.845-852
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    • 2003
  • This study deals with the relationship between the red tide occurrence and the meteorological and marine factors, the prediction of areas where the red tide is likely to occur based on the information, and the satellite monitoring for the red tide in mid-South Sea of Korea. From 1990 to 2001, the red tide was observed every year and the number of occurrences increased as well. The red tide mostly occurred in July, August, and September. The most important meteorological factor governing the mechanisms of the increase in the number of red tide occurrences is found to be a heavy precipitation. It was found that the favorable marine environmental conditions for the red tide formation are some of marine factors such as the warm water temperature, the low salinity, the high suspended solid, the low phosphorus, and the low nitrogen. The necessary conditions for the red tide occurrence are found to be the heavy precipitation (23.4-54.5 mm) for 2∼4 days, the warm temperature $(24.6∼25.9^{\circ}C)$, proper sunshine (2∼10.3 h), and light winds (2∼4.6 m/s & SW) for the day in red tide occurrence. It was possible to monitor the spatial distributions and concentration of the red tide using the satellite images. It was found that the likely areas for red tide occurrence in August 2000 were Yosu - Dolsan coast, Gamak bay, Namhae coast, Marado coast, Goheung coast, and Deukryang bay.

Characteristics of Meteorological and Marine Environments for the Red Tide Occurrence in Mid-South Sea of Korea (한국 남해중부해역의 적조발생에 관한 기상 및 해양환경 특성)

  • 윤홍주;김승철;박일흠
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.05a
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    • pp.323-328
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    • 2003
  • This study deals with the relationship between the red tide occurrence and the meteorological and marine factors, the prediction of areas where the red tide is likely to occur based on the information, and the satellite monitoring for the red tide in mid-South Sea of Korea. From 1990 to 2001, the red tide was observed every year and the number of occurrences increased as well. The red tide mostly occurred in July, August, and September. The most important meteorological factor governing the mechanisms of the increase in the number of red tide occurrences is found to be a heavy precipitation. It was found that the favorable marine environmental conditions for the red tide formation are some of marine factors such as the warm water temperature, the low salinity, the high suspended solid, the low phosphorus, and the low nitrogen. The necessary conditions for the red tide occurrence are found to be the heavy precipitation (23.4∼54.5 mm) for 2∼4 days, the warm temperature (24.64-25.85 $^{\circ}C$), proper sunshine (2∼10.3 h), and light winds (2∼4.6 m/s & SW) for the day in red tide occurrence. It was possible to monitor the spatial distributions and concentration of the red tide using the satellite images. It was found from this study that the likely areas for red tide occurrence in August 2000 were Yosu ∼ Dolsan coast, Gamak bay, Namhae coast, Marado coast, Goheung coast, and Deukryang bay.

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Three Antioxidant Compounds of the Red Alga Liagora farinosa

  • Hannoda, Hala M.;Badr, Jihan M.;Yousef, Diaa T.A.
    • Natural Product Sciences
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    • v.13 no.2
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    • pp.140-143
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    • 2007
  • Investigation of the chloroform soluble fraction of the red alga Liagora farinosa, collected from Hurghada at the Red Sea resulted in the isolation of three compounds; a nucleoside (thymidine) and two glycosides (methyl-${\beta}$-D-xylopyranoside and glycerol-2-${\alpha}$-D-glucopyranoside). The structures of the isolated compounds were established on the basis of different spectroscopic techniques as well as comparison with the previously published data. This is the first report for the isolation of the three compounds fron red algae; moreover, the compounds were examined for their antioxidant activity and showed variable activity.

Growth and Blood Characteristics of Red Sea Bream Pagrus major by Starvation and Stocking Density during Red Tide (적조발생시기 참돔의 절식과 사육밀도에 따른 성장과 혈액성상)

  • Kim, Won-Jin;Lee, Jeong-Yong;Shin, Yun-Kyung;Won, Kyoung-Mi
    • Korean Journal of Ichthyology
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    • v.30 no.4
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    • pp.194-204
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    • 2018
  • In order to minimize the damage on the red sea bream Pagrus major by a harmful dinoflagellate Cochlodinium polykrikoides, we investigated the effect of feeding, starvation and stocking density on the survival rate, growth, growth restoration and physiological response of P. major exposure to C. polykrikoides. The experimental groups were divided into three groups such as F-HD (feeding and high density with $6.4kg/m^3$), S-HD (starvation and high density with $6.4kg/m^3$) and S-LD (starvation and low density with $3.2kg/m^3$) according to stocking density and starvation in marine cage ($11m{\times}11m{\times}5m$). The F-HD was fed throughout the experiment for 9 weeks, whereas S-HD and S-LD were not fed for 5 weeks and then refeeding for 4 weeks. Survival rate was the lowest in F-HD (85.5%) and S-LD was the highest (97.3%). The growth rates of S-HD and S-LD were significantly lower than F-HD during starvation period for 4 weeks, but rapidly recovered after feeding. The nutritional status such as ALB, TP, TCH, TG were similar to tendency of growth data. Ht, Hb, AST, ALT and GLU levels were significantly higher in the F-HD than in the starvation groups at the same time (in 3 week) during starvation period. But starvation groups did not differ during starvation period. As a result, F-HD is more sensitive to stress than S-HD and S-LD. Thus, during C. polykrikoides bloom period, starvation and stocking density control can help survival and growth restoration of the red sea bream.

A Study on Measuring Procedure and Analysis Technique of Ship Infrared Signature at Sea (해상에서 적외선신호의 계측절차 및 분석기법 연구)

  • Cho, Yong-Jin
    • Journal of Ocean Engineering and Technology
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    • v.23 no.3
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    • pp.53-58
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    • 2009
  • A scale model test for ship Infra-Red signature measurements at sea is impossible, because it is sensitive to the environment. Since we can't control the meteorological environment of the real sea, it can't be carried out with the desired maritime environments. Therefore, in the sea, we made measurements of the weather, operating conditions of the ship, and ship IR signatures under given conditions, and then analyzed them. Conversely, we compared the results of the test with a prediction for a given scenario condition. This paper describes the test items, procedures, and measuring instruments of the experiments at sea and the results from basic researches for methods of estimation and analysis of the measured data.

Biochemical analysis of blood serum from wintering seabream with green liver syndrome (저수온기 돔류의 녹간증 혈청성분)

  • Choi, Hye-Sung;Park, Sung-Real;Jung, Choon-Goo
    • Journal of fish pathology
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    • v.15 no.1
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    • pp.43-48
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    • 2002
  • A blood biochemical analysis was carried out for the serum of wintering sea bream (red sea bream Pagrus major, black sea bream Acanthopagrus schlegeli, rock bream Oplegenathus fasciantuas) with green liver syndrome. GOT and GPT were significantaly elavated in the diseased sea bream. The value of $NH_{3}$ was slightly higher but those of TBIL. TP and UA were lower than the control. But there were no differences in albumin. Ca and glucose between the diseased and the control. These results suggent that a green liver syndrome in the sea bream might be related with nutritional defects and the stress of low water temperature during the winter.

Detection of Fish Killing Dinoflagellates Cochlodinium polykrikoides and Karlodinium veneficum (Dinophyceae) in the East China Sea by Real-time PCR

  • Park, Tae-Gyu;Kang, Yang-Soon;Park, Young-Tae;Bae, Heon-Meen;Lee, Yoon
    • ALGAE
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    • v.24 no.2
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    • pp.105-110
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    • 2009
  • The rDNAs of figh-killing dinoflagellates Cochlodinium polykrikoides and Karlodinium veneficum were detected from the East China Sea by species-specific real-time PCR probes. Sequence analysesusing the partial ITS sequences from the real-time PCR products showed identical sequences with C. Polykrikoides and K. veneficum, respectively and low expectation values (E-value) of less than 1e-5 suggesting the presence of these organisms in the East Ching Sea shelf water that flows into the Tsushima Strait and the Yellow Sea.

Fatty Acid Compositions of Sea Algaes in the of Korea

  • Choe, Sun-Nam;Choi, Kang-Ju
    • Proceedings of the Korean Journal of Food and Nutrition Conference
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    • 2001.12a
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    • pp.125-125
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    • 2001
  • Total lipid contents were 0.58∼3.00% in 9 kinds of brown algaes, 0.47∼2.16% in 5 kinds of red algaes and 0.55∼2.99% in 2 kind of green algeas, respectively. Fatty acid compositions of the algaes were determined by gas liquid chromatography. Total polyenes and n-3 polyenes of linoleic acid(18:3), stearidonic acid(18:4), eicosapentaenoic acid(20:5) and docosahexaenoic acid(22:6) were 3.88∼57.57% and 1.46∼25.67% in the brown algaes, 5.30∼39.75% and 1.17∼21.91% in the red algaes, and 7.76∼19.27% and 3.67%∼10.61% in the green algaes, respectirely. The fatty acid contents and compositions of total polyenes and n-3 polyenes were vary different in the algae groups and sepecies.

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