• Title/Summary/Keyword: Korea strait

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Organic Carbon, Calcium Carbonate, and Clay Mineral Distributions in the Korea Strait Region, the Southern Part of the East Sea

  • Khim, Boo-Keun;Shin, Dong-Hyeok;Han, Sang-Joon
    • Journal of the korean society of oceanography
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    • v.32 no.3
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    • pp.128-137
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    • 1997
  • This study presents results from a detailed sedimentological investigation of surface sediments obtained from the Korea Strait region, the southern part of the East Sea (Sea of Japan). The distribution of different types of bottom sediments is controlled by the recent fine-grained sediment transport and deposition combined with the lowerings of sea level during the last glacial period, forming a diverse mixture of organic-rich fine-grained and shelly coarse-grained sediments. In comparison to high organic concentration of fine-grained sediments in the inner continental shelf and slope areas, the shell-rich coarse-grained sediments on the outer shelf are discernible being further modified. These coarse-grained sediments are confirmed as relict resulting from the sediment dynamics during the lower sea levels of the last glacial period. Clay mineral distribution of the fine-grained sediments gives information about the transport mechanism. Presence of present-day current system (the Tsushima Warm Current) is most probable source for the fine-grained particles into the open East Sea from the East China Sea, indicating that Holocene sediment dynamics may be used to explain the observed distribution of surface coarse-grained shell-rich sediments.

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Hourly Change of Temperature and Salinity in the Korea Strait (대한해협의 수온 및 염분의 시간적 변동)

  • Park, Chung Kil
    • 한국해양학회지
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    • v.7 no.1
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    • pp.15-18
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    • 1972
  • The observations of hourly change of salinity and temperature were made in the Korea Strait from August 1968 to July 1969. The largest hourly change of salinity and temperature was shown in August and the smallest in April. The range of hourly change of temperature (5.67-15.75$^{\circ}C$ on the depth of 125m) and salinity (32.1-34.3 on 20m layer) were significantly wide in August. These changes are correlated with the movement of water masses vertically and horizontally caused by changing direction and force of the current.

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Thermal plasticity of growth and chain formation of the dinoflagellates Alexandrium affine and Alexandrium pacificum with respect to ocean acidification

  • Lee, Chung Hyeon;Min, Juhee;Lee, Hyun-Gwan;Kim, Kwang Young
    • ALGAE
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    • v.36 no.4
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    • pp.285-298
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    • 2021
  • The amount of CO2 absorbed by the oceans continues to rise, resulting in further acidification, altering some functional traits of phytoplankton. To understand the effect of elevated partial pressures of CO2 (pCO2) on functional traits of dinoflagellates Alexandrium affine and A. pacificum, the cardinal temperatures and chain formation extent were examined under two pCO2 (400 and 1,000 µatm) over the range of temperature expected to be associated with growth. The growth rate and chain formation extent of A. affine increased with higher pCO2, showing significant changes in cardinal temperatures and a substantial increase in middle chain-length (4-8 cells) fractionation under elevated pCO2 condition. By contrast, there were no significant differences in specific growth rate and any chain-length fractionation of A. pacificum between ambient and elevated pCO2 conditions. The observed interspecies variation in the functional traits may reflect differences in ability of species to respond to environmental change with plasticity. Moreover, it allows us to understand the shifting biogeography of marine phytoplankton and predict their phenology in the Korea Strait.

The oceanic condition of the Tsushima Warm Current region the southern part of the East Sea (Sea of Japan) In June, 1996

  • Lee Chung Il;Cho Kyu Dae
    • Proceedings of KOSOMES biannual meeting
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    • 2003.11a
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    • pp.167-174
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    • 2003
  • Oceanic conditions of the Tsushirm Wann Current (1WC) region in the southern area if the East Sea (the Japan Sea) are examined using data obtained from a CREAMS (Circulation Research if the East Asian Marginal Seas) cruise in June 1996. In 1990s, a lower temperature appears in $19\%$ and in this period, two branch of the TWC exist and the first branch of the TWC flows inshore if the Japanese coastal region compared to tfr1t in the other years, especially in the sfr1llower water layer at less th:1n about 2mm. The TWC cored with the higher salinity (>34.6 psu) is clearly observed over the continental shelf zone in the Japanese coastal region and offshore and identified by geostrophic calculation Intrusion if the TWC into the East Sea through the Korea Strait (the Tsushima Strait) makes the density structure in the water column change and the water mass in the TWC region is unstable based on Brunt- Vaisala frequency.

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Sea Lines of Communication Security and Piracy (해상교통로(SLOC) 안보와 해적: 소말리아 해적퇴치작전 경험을 중심으로)

  • Kim, Meoung-Sung
    • Strategy21
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    • s.36
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    • pp.150-179
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    • 2015
  • This thesis analyzes Somali piracy as a non-traditional threat to the Sea Lines of Communication (SLOC) and international countermeasures to the piracy. In an era of globally interdependent economies, the protection of sea lines and freedom of navigation are prerequisites for the development of states. Since the post-Cold War began in the early 1990s, ocean piracy has emerged as a significant threat to international trade. For instance, in the Malacca Strait which carries 30 percent of the world's trade volume, losses from failed shipping, insurance, plus other subsequent damages were enormous. Until the mid-2000s, navies and coast guards from Malaysia, Indonesia, Singapore, together with the International Maritime Organization (IMO), conducted anti-piracy operations in the Strait of Malacca. The combined efforts of these three maritime states, through information sharing and with reinforced assets including warships and patrol aircrafts, have successfully made a dent to lower incidents of piracy. Likewise, the United Nations' authorization of multinational forces to operate in Somali waters has pushed interdiction efforts including patrol and escort flotilla support. This along with self-reinforced security measures has successfully helped lower piracy from 75 incidents in 2012 to 15 in 2013. As illustrated, Somali piracy is a direct security threat to the international community and the SLOC which calls for global peacekeeping as a countermeasure. Reconstructing the economy and society to support public safety and stability should be the priority solution. Emphasis should be placed on restoring public peace and jurisdiction for control of piracy as a primary countermeasure.

Evaluation and Comparison of Bank Efficiency in Cross-Strait after ECFA

  • LIAO, Chang Sheng
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.10
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    • pp.783-793
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    • 2020
  • The purpose of this study is to investigate whether the ECFA impacted the efficiency of banks in China and Taiwan from 2008 to 2017. This study follows Seiford and Zhu (2002), who recommend using the standard data envelopment analysis model to measure performance by increasing the desirable outputs and decreasing the undesirables. The finding was that overall technical efficiency increased from 2012 to 2017, reaching 0.575, 0.652, 0617, 0.689, 0.701 and 0.74, respectively. This result implies bank efficiency did indeed improve after China and Taiwan signed the ECFA cooperation agreement. The study found that the mean technical efficiency was 0.8756 in China, greater than Taiwan's mean of 0.3511, implying that Chinese banks experienced a greater increase in efficiency after signing the EFCA. One possible reason explored in this study is that China's economy is currently growing at the highest rate in the world, and the banks' efficiency has benefited from greater economic growth. This suggests that cross-strait sustained negotiations to consummate an agreement on trade in the services will be a very important mission in the future. This result also provides significant evidence suggesting that not accounting for undesirable output while estimating the evolution of the model may seriously distort efficiency results.

Characteristics of Front near the Cheju Strait in Early Winter (초겨울 제주해협 근해에서 형성되는 전선의 특성)

  • LEE Jae Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.2
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    • pp.51-58
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    • 1983
  • Off the southwest coast of Korea, changes in hydrographic fields from stratified state of summer to a vertically homogeneous one of winter appeared to occur most actively in November. During this transitional period coincident thermal and salinity fronts are formed along the boundary between the two water masses of cold coastal water with low salinity and of the Tsushima Current Water. Generally frontal zone lies where the bottom depth is about 70-90m except for the central region of the Cheju Strait in which the influence of the Tsushima Current is weak. Result of the drift bottle experiment in November 1930 supports the existence of the westward coastal current.

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A New Record of Thalassometridae (Crinoidea, Comantulida, Oligophreata) in Korea (바다갯고사리과(바다나리강, 바다나리목, 협중강아목)의 1 한국미기록종)

  • Shin Sook
    • Animal Systematics, Evolution and Diversity
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    • v.20 no.2
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    • pp.185-189
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    • 2004
  • Taxonomic study for the comantulid crinoids collected from Korea Strait was conducted. A oligophreatan species, Parametra orion (A. H. Clark, 1907) belonging to the family Thalassometridae, was identified and turned out to be new to the Korean fauna. The family Thalassometridae is newly reported in Korea.

Two New Species of Asterocheridae (Copepoda, Siphonostomatoida) from Korea

  • Kim, Il-Hoi;Je, Jong-Geel
    • Animal cells and systems
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    • v.4 no.4
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    • pp.305-314
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    • 2000
  • Two new species of Asterocheridae are described from Korean seas: Acontiophorus pilosus associated with a bryozoan of Celeporina sp. in the Sea of Japan and Asteropontius bifurcatus associated with the antipatharian Antipathes japonicus in Jeju Island in Korea Strait. A key to the species of Acontiophorus is provided.

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