• 제목/요약/키워드: red Sea

검색결과 643건 처리시간 0.026초

X-Band 레이더를 이용한 해양오염 관측기법에 관한 연구 (A Study of a Method for Detecting Marine Pollution Using X-band Radar)

  • 박승근;양영준;박준수;권순홍
    • 한국해양공학회지
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    • 제24권2호
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    • pp.53-56
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    • 2010
  • Oil spills and red tide can be very damaging to the environment and fishery farming. These catastrophic accidents must be detected as quickly as possible. In this paper, we report the results of applying the wavelet transform to SAR or marine radar images for the detection of the boundaries of an oil spill or red tide. The application of the wavelet transform to these phenomena looks quite promising in detecting the boundaries of oil spills and red tide areas.

OSMI ocean color products with updated cross-calibration coefficients

  • Lee S. G.;Kim Y. S.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.494-497
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    • 2004
  • To date the KOMPSAT OSMI(Ocean Scanning Multi-spectral Imager) data have been widely used in natural disaster monitoring such as Typhoon, Asian Dust, Red Tide, and Forest Fire. Quantitative analyses related to the marine ecosystem have been delayed because they require good quality of data through Cal/Val activities. To resolve such problem, KARI performed the OSMI crosscalibration study with SeaWiFS team. In this study, we will demonstrate the OSMI ocean color products with updated cross-calibration coefficients and compare them to the previous cross-calibration results.

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PATH VARIABILITY OF THE CHANGJIANG DILUTED WATER IN SUMMER

  • Yang, Joon-Yong;Cho, Yang-Ki;Chang, Kyung-Il;Suh, Young-Sang
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.688-691
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    • 2006
  • The current system of the East China Sea, a marginal sea in the northwest Pacific, has a seasonal variation. The Changjiang Diluted Water, Chinese coastal water in the East China Sea, has different seasonal paths. It flows southward along the Chinese coast within a narrow band in winter and does northeastward the Korea/Tsushima Strait in summer, which has been a subject to many researchers. In particular, low salinity in the South Sea of Korea in 1996 and 1998 was in discord with the Changjiang River discharge and the Changjiang Diluted Water seems to play an important role in occurrence of red tide in the South Sea of Korea in 1997 and on the contrary, disappearance in the next year. These facts suggested that the Changjiang Diluted Water does not flow along the same path in every summer. According to the analyses for path of the Changjiang Diluted Water using ocean color images by SeaWiFS and salinity observations by shipboard CTD in August for recent years, the Changjiang Diluted Water in summer flowed within the range of direction from southeastward to north-northeastward anticlockwise. However, the Changjiang Diluted Water flowed northeastward toward Jeju Island of Korea for the most part. It is necessary to examine the influence of major factors on path variability of the CDW in summer such as surface wind, the Changjiang River discharge and background current.

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해산 극피동물 중의 당단백질의 특성과 이용 II. 해삼당단백질과 황산콘드로이친의 항돌연변이 및 항암효과 (Antimutagenic and Anticancer Effects of Glycoprotein and Chondroitin Sulfates from Sea Cucumber(Stichopus japonicus))

  • 류홍수;문정혜;양훈석;서재수
    • 한국식품영양과학회지
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    • 제27권2호
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    • pp.350-358
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    • 1998
  • The antimutagenic and anticancer activities of glycoprotein(GP) and chondroitin sulfate(CS) from sea cucumbers were studied using Ames mutagenicity test and human cancer cells culture test. The GP's inhibitory effect toward aflatoxin B1(AFB1) and 3, 2'-dimethyl-4-amino-biphenyl(DMAB) increased with the higher added concentrations up to 5% level(w/w) regardless fractionation methods. The GP from sea cucumbers through DEAE-cellulose column chromatography showed an inhibitory effect ranged from 84 to 98%, and the maximum antimutagenicities resulted in red sea cucumber with 98% (AFB1) and 95% (DMAB). But 5% level of CS from various sea cucumbers had an inhibitory effect toward those both indirect mutagens ranged from 79% to 85%. However, in case of direct mutagens(N-methyl-N'-nitro-N-nitrosoguanidine, MNNG and 4-nitroquinoline-1-oxide, 4-NQO), the GP's inhibitory effect was 55∼78% and the CS had a low inhibitory effect(58∼70%) at the added level of 5%. The GP from sea cucumbers exhibited the strong inhibitory effects with 89∼95% and 82∼92% on the growth of HT-29 human crcinoma cells and AZ-521 human gastric cancer cells (at 5% level).

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Megalocytivirus 감염 해산 어류에서 나타나는 임상증상의 정량적 변화 분석 (Quantitative analysis of the clinical signs in marine fish induced by Megalocytivirus infection)

  • 진지웅;조혜진;김광일;정준범;박경현;정현도
    • 한국어병학회지
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    • 제24권2호
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    • pp.53-64
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    • 2011
  • Megalocytivirus 감염 시 나타나는 임상적 증상의 정량적인 분석을 위하여, 돌돔에서 분리된 megalocytivirus IVS-1을 돌돔성어와 치어에 인위 감염시켰다. 그 결과 spleen index가 각각 $4.49{\pm}1.13$$4.85{\pm}1.06$로 나타 났으며, 이것은 정상배에 비해 3배 이상 증가한 값이었다. 폐사율은 돌돔성어와 치어에서 모두 100% 폐사한 반면 참돔치어는 30일이 지나도 60%의 폐사만 나타나 돌돔폐사율에 비해 낮은 폐사율을 나타냈다. 또한 IVS-1을 감염시킨 빈사상태의 참돔치어는 spleen index가 동일 크기의 돌돔치어 보다 낮은 $1.47{\pm}0.87$을 보였다. Real-time PCR을 이용하여 감염의 진행에 따른 바이러스 농도를 측정한 결과, 돌돔 치어와 성어의 감염 조직 내 바이러스 최고 농도는 각각 $2.03{\times}10^7$ copies/mg과 $2.40{\times}10^7$ copies/mg으로 비슷하였으나 돌돔성어에서 먼저 최고치에 도달하였다. 더구나 비장의 비정형비대세포의 수 역시 돌돔치어의 경우 지속적으로 증가한 반면 돌돔성어의 경우 최고치에 도달 후 오히려 감소히는 경향을 보였다. 본 연구에서는 megalocytivirus 감염 시 조직의 형태적 변화와 조직 내의 바이러스 농도와 같은 임상적인 증상을 정량적인 분석을 통해 나타내었고 이러한 정량적인 수치와 megalocytivirus 감염의 진행 정도와의 상관관계에 대해 조사하였다.

Ichthyotoxic Cochlodinium polykrikoides red tides offshore in the South Sea, Korea in 2014: III. Metazooplankton and their grazing impacts on red-tide organisms and heterotrophic protists

  • Lee, Moo Joon;Jeong, Hae Jin;Kim, Jae Seong;Jang, Keon Kang;Kang, Nam Seon;Jang, Se Hyeon;Lee, Hak Bin;Lee, Sang Beom;Kim, Hyung Seop;Choi, Choong Hyeon
    • ALGAE
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    • 제32권4호
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    • pp.285-308
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    • 2017
  • Cochlodinium polykrikoides red tides have caused great economic losses in the aquaculture industry in many countries. To investigate the roles of metazooplankton in red tide dynamics of C. polykrikoides in the South Sea of Korea, the abundance of metazooplankton was measured at 60 stations over 1- or 2-week intervals from May to November 2014. In addition, the grazing impacts of dominant metazooplankton on red tide species and their potential heterotrophic protistan grazers were estimated by combining field data on the abundance of red tide species, heterotrophic protist grazers, and dominant metazooplankton with data obtained from the literature concerning ingestion rates of the grazers on red tide species and heterotrophic protists. The mean abundance of total metazooplankton at each sampling time during the study was 297-1,119 individuals $m^{-3}$. The abundance of total metazooplankton was significantly positively correlated with that of phototrophic dinoflagellates (p < 0.01), but it was not significantly correlated with water temperature, salinity, and the abundance of diatoms, euglenophytes, cryptophytes, heterotrophic dinoflagellates, tintinnid ciliates, and naked ciliates (p > 0.1). Thus, dinoflagellate red tides may support high abundance of total metazooplankton. Copepods dominated metazooplankton assemblages at all sampling times except from Jul 11 to Aug 6 when cladocerans and hydrozoans dominated. The calculated maximum grazing coefficients attributable to calanoid copepods on C. polykrikoides and Prorocentrum spp. were 0.018 and $0.029d^{-1}$, respectively. Therefore, calanoid copepods may not control populations of C. polykrikoides or Prorocentrum spp. Furthermore, the maximum grazing coefficients attributable to calanoid copepods on the heterotrophic dinoflagellates Polykrikos spp. and Gyrodinium spp., which were grazers on C. polykrikoides and Prorocentrum spp., respectively, were 0.008 and $0.047d^{-1}$, respectively. Therefore, calanoid copepods may not reduce grazing impact by these heterotrophic dinoflagellate grazers on populations of the red tide dinoflagellates.

판별함수에 의한 진해만 적조예측 (The Prediction of Red Tides in Jinhae Bay using a Discriminant Function)

  • 이문옥;백상호
    • 한국환경과학회지
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    • 제7권1호
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    • pp.8-19
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    • 1998
  • The dicriminant function was introduced to understand the cause and establish the prediction method of red tides occurring In Jinhae Bay. Korea. Two sea re91ons of Masan and Haengam Bays and Dang- dong and Wonmun Bays had different types of causes and patterns for red tides. In Masan and Haengam Bays, the red tides concentrically occurred during June and September. For example, in .lune the red tides occurred from physical and meteorological factors, which are related to the stratification and the increase in planktons. However in August the red tides occurred from the water quality environment, based on these conditoins. Futhermore, in September the red tides were caused by the balance between the meteorological and water quality environmental factors. In contrast to those, In Dangdong and Won-mun Bays, the red tides mainly occurred during July and October and the frequency of occurrence was not as much as Masan and Haengam Bays. Especially, in August and September most meteorological and physical factors or water quality environmental factors appeared to contribute to the occurrence of red tides. This indicates that red tides do not easily occur as they are controlled by various environmental factors particularly in these regions The discriminant functions were applied to predict red tides which they were actually occurred In Masan and Haengam Bays in June. The results showed that they were successful for the prediction of red tide at Haengam Bay but not at Masan Bay. The reason for their discrepancy in Masan Bay could have come from using a slight higher value of pH or COD in May, instead of its value in June.

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GSIS 이용한 적조발생지의 공간결정 연구 (A Study on the Spatial Determination of Red Tide Occurrence Area Using GSIS)

  • 김진기
    • 대한공간정보학회지
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    • 제15권2호통권40호
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    • pp.51-57
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    • 2007
  • 기존 유해성 적조의 발생해역에 대한 공간결정 연구는 미비하였으며, 적조발생지와 소멸지에 대한 공간을 정확하게 판단하기 어려웠다. 따라서 좀 더 객관적이며, 과학적인 방법으로서 적조의 발생과 이동에 따른 시 공간적인 방법으로의 분석 필요성이 대두 되고 있다. 본 연구에서는 매년 발생되는 유해성 적조 발생지에 대한 공간을 파악하기위해 수치지형도를 이용한 GSIS기법을 적용 해안선을 추출하였으며, 수년간 발생된 적조발생 자료를 근거로 발생지의 공간위치를 결정하여 분석한 결과 연구지 중 여자만 일대에서는 적조의 발생이 거의 없었음을 알 수 있었고 남해 돌산도와 남해도 앵강만 해역일대에서 최고의 발생빈도를 나타냄을 알 수 있었다. 이를 근거로 매년 반복적으로 발생되는 해역에 대한 적조의 분포상황을 시공간적으로 판단하여 이동경로 해역의 예측과 피해의 사전예방이 가능하리라 판단된다.

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특수섬유를 이용한 보안용지의 개발 (Use of New Fibers for the Development of Security Paper)

  • 정선영;길상혁;김영욱;서영범
    • 펄프종이기술
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    • 제44권1호
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    • pp.16-23
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    • 2012
  • Use of security papers for monetary papers, gift certificates, and lottery tickets increases every year. As the use of security papers increase, there are more possibility of counterfeits. In this study, we used unique fibers from the sea to increase the difficulties against counterfeiting. The red algae fibers give opacity as much as calcium carbonates, and have unique shape in length ($500{\sim}900\;{\mu}m$) and width ($1{\sim}4\;{\mu}m$) to be discerned from other natural fibers such as wood and cotton fibers. We mixed red algae fibers to wood fibers in a series of fixed ratios to make single and multiply papers for making security papers. Paper with dyed red algae fibers were also used. Paper made without fillers gave enough opacity for printing when red algae fibers were used more than 20% of the fiber furnish. Those properties may allow red algae fibers to be a potential candidate for fiber raw materials of security paper.

알루미늄 제련 폐기물(Red Mud)의 활성화 방법에 따른 수용상의 인산염 제거특성 (Phosphate Removal from Aqueous Solution according to Activation Methods of Red Mud)

  • 김이태;배우근;김우정
    • 한국물환경학회지
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    • 제20권5호
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    • pp.466-472
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    • 2004
  • Red mud is formed as a waste during bauxite refining known as Bayer's process. Its main constituents are iron, aluminium, sodium and silica. The disposal of large quantities of wasted red mud causes a serious ecological problem. In this study, the red mud wasted from the bauxite refinery was studied for phosphate removal from aqueous solution according to activation methods. The influence of heat treatment, and neutralization with sea water and acid treatment level for the optimum conditions for phosphate removal have been determined. Heat treatment combined with acid treatment is most suitable for the removal of phosphate from aqueous solution. The optimal condition was activated with 1 N HCl solution after heating in $600^{\circ}C$ during 4 hours. Acid and heat treatment causes sodalite compounds which hinder the phosphate adsorption to leach out. The adsorption data obtained followed a first-order rate expression and fitted well with the Freundlich Isotherm well.