• Journal of the korean society of oceanography
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• v.38 no.2
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• pp.80-86
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• 2003

The horizontal distributions of $^{224}Ra$ (half life=3.4 days) and $^{223}Ra$ (half life=11.3 days) were measured in surface seawaters of the Nakdong River estuary and the South Sea of Korea in April and October 2002. In order to determine these short-lived Ra isotopes, we used a delayed coincidence counter which is much more rapid and accurate than traditional methods. In an estuarine mixing zone (salinity, ~l6 ppt), the activities of $^{224}Ra\;and\;^{223}Ra$ were much greater than what would be expected from a mixture of freshwater and seawater in the Nakdong River estuary. This excess Ra may be a result of Ra desorption from fresh sediments originating from the river upstream. However, in the more open areas of the Nakdong River estuary (salinity>30 ppt) and the South Sea of Korea, $^{224}Ra\;and\;^{^{223}Ra$ activities decreased exponentially as a function of distance offshore. Using the decrease of $^{223}Ra$ with distance offshore in the South Sea of Korea, we estimated the apparent horizontal eddy diffusivities. The apparent eddy diffusion coefficients in South Sea of Korea are calculated to be approximately $3500-8000\;\textrm{m}^2/sec$.

• Korean Journal of Remote Sensing
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• v.15 no.1
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• pp.51-60
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• 1999

Today, satellite remote sensing plays an important role as a advanced science and technology, and becomes a superpower tool of the study and research in various fields of Earth Science. UN proclaimed that 1998 was the year of the oceans, and WMO chose the title of 'Weather, Ocean and Human activity' as the principal subject of the day of the world meteorology in march 23, 1998, respectively. As previously announced, these two memories give the great meaning for satellite remote sensing in oceanography. Therefore, this study reviews satellite oceanography for many specialists in the fields of the ocean and fishery science. In future, satellite oceanography will be greatly used to observe, monitor and predict various phenomena associated with the oceans, in order to seek safety in a natural disaster, and menage and conserve the oceanic environments and resource.

• ALGAE
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• v.35 no.4
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• pp.375-388
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• 2020

Ocean acidification and warming, identified as environmental concerns likely to be affected by climate change, are crucial determinants of algal growth. The ichthyotoxic raphidophytes Chattonella species are responsible for huge economic losses and environmental impact worldwide. In this study, we investigated the impact of CO2 on the thermal performance curves (TPCs) of Chattonella marina and Chattonella ovata grown under temperatures ranging from 13 to 34℃ under ambient pCO2 (350 μatm) and elevated pCO2 (950 μatm). TPCs were comparable between the species or even between pCO2 levels. With the exception of the critical thermal minimum (CTmin) for C. ovata, CTmin for C. marina and the thermal optimum (Topt) and critical thermal maximum (CTmax) for both species did not change with elevation of pCO2 levels. While CO2 enrichment increased the maximum photosynthetic rates (Pmax) up to 125% at the Totp of 30℃, specific growth rates were not significantly different under elevated pCO2 for the two species. Overall, C. ovata is likely to benefit from climate change, potentially widening its range of thermal tolerance limit in highly acidic waters and contributing to prolonged phenology of future phytoplankton assemblages in coastal waters.

• 한국해양학회지
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• v.11 no.2
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• pp.71-76
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• 1976

This work concerns with the biotic study of the polychaeta population in the intertidal flat, Inchon, Korea. Magelona japonica was found to be the most abundant species, comprising 54% of total organisms examined. The presence of large numbers of Magelona japonica and Sternaspis scutata, high value of species diversity indices (H(s)), and the absence of the particular pollution indicator species, except a few Prinospio pinnata, suggest that the study area appears not to be polluted during the study period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.836-838
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• 1994

1993년에 동해안의 고리, 월성, 울진 앞바다에서 저서어류의 생물상을 계절별로 조사했다. 그 결과 지금까지 남해와 서해에 분포한다고 알려진 참조기를 고리와 월성에서 각각 13마리 (표준체장 $131.8{\sim}180.1mm$)와 1마리 (170.2mm) 채집하여, 본 종이 동해에도 분포하고 있다는 것을 확인했다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.6
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• pp.375-384
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• 1990

A numerical experiment is made to study the combined effect of differential cooling and bottom topography on the formation of Ulleung Warm Eddy. The Ulleung Warm Eddy appears after the passage around the Ulleung Basin of coastal trapped baroclinic waves generated in the north initial density front to the north, the continental slopes both to the west and south, and the Yamato Rise to the east. It resides therefore always inside the Ulleung Basin, as confirmed by observations.

• Journal of the korean society of oceanography
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• v.35 no.2
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• pp.78-88
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• 2000

A weakly viscous wave and an approximate variational principle in viscous fluids are introduced, with which we can interpret the fundamentals such as how viscosity dissipation occurs with time elapse, and how the free surface boundary layer exists at the wavy surface in weakly viscous fluids. As an application, responses of a spherical buoy on the weakly viscous capillary gravity wave are investigated to show the viscosity effects. At the end, surfactant problems are briefly reviewed with the view of short viscous waves as expected future applications.

• Journal of the korean society of oceanography
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• v.31 no.1
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• pp.32-36
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• 1996

The oyster shell bed (more than 47 cm thick) atop the Gaipri Point (granite coastal bluff) in the Hampyung Bay, southwest coast of Korea which is a coastal area of southeastern margin of the Yellow Sea basin has been interpreted as unique typhoon deposit formed at about 3610 yr BP or later. The unconformable boundary between the oyster shell bed by typhoon and the granitic soil horizon of the Gaipri Point is 820 cm high above the mean high-tide water level (MHWL). The $^{14}C$ age of the oyster shells is 3610${\pm}$70 yr BP.

• Journal of the korean society of oceanography
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• v.31 no.3
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• pp.117-122
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• 1996

Oxygen consumption by the Manila clam, Ruditapes philippinarum (Bivalvia: Veneridae) maintained in a culture tank for 7-10 weeks was measured with an automatic intermittent-flow-respirometer (AIFR). There was evidence for an endogenous tidal rhythm of 12.4 h in oxygen consumption, at irregular intervals of between about 7 and 18 hours during experiments of between 22 h 5 min and 70 h 32 min (duration) recording for fasting animals in constant darkness at constant temperatures in the absence of tidal rhythms.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2000.09a
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• pp.182-187
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• 2000

Laboratory for Coastal and Ocean Dynamics Studies at Sungkyunkwan University and Department of Physical Oceanography, Institute of Oceanology, Chinese Academy of Sciences has been working on cooperative studies on ocean circulation. (omitted)