• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1078-1089
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• 2017

Biofilm formation of Staphylococcus aureus is one of its mechanisms of drug resistance. Anti-biofilm screening of 106 compounds from marine-derived fungi displayed that 12 compounds inhibited S. aureus biofilm formation by >50% at the concentration of $100{\mu}g/ml$, and only secalonic acid D (SAD) and B inhibited by >90% at $6.25{\mu}g/ml$ without inhibiting cell growth after 24-h incubation. Meanwhile, it was found that the double bond between C-1 and C-10 of citrinin derivatives and the C-C connection position of two chromone monomers may be important for their anti-biofilm activities. Moreover, SAD slightly facilitated biofilm eradication and influenced its architecture. Furthermore, SAD slowed the cell growth rate in the preceding 18-h incubation and differentially regulated transcriptional expression of several genes, such as agr, isaA, icaA, and icaD, associated with biofilm formation in planktonic and biofilm cells, which may be the reason for the anti-biofilm activity of SAD. Finally, SAD acted synergistically against S. aureus growth and biofilm formation with other antibiotics. These findings indicated that various natural products from marine-derived fungi, such as SAD, could be used as a potential biofilm inhibitor against S. aureus.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.327-331
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• 2007

23 tropical cyclones of tropical storm(TS) intensity or higher formed in the western North Pacific and the South China Sea in 2006. The total number is less than the 30-year $(1971{\sim}2000)$ average frequency of 26.7, Out of 23, 15 cyclones reached typhoon(TY) intensity, three severe tropical storm(STS) intensity, and five TS intensity. The tropical cyclone season in 2006 began in May with the formation of CHANCHU(0601). While convective activity was slightly inactive around the Philippines from late June to early August. In addition, subtropical high was more enhanced than normal over the south of Japan from May to early August. Consequently, most tropical cyclones formed over the sea east of the Philippines after late June, and many of them moved westwards to China. CHANCHU(0601), BILIS(0604), KAEMI(0605), PRAPIROON(0606) and SAOMI(0608) brought damage to China, the Philippines, and Vietnam. On the other hand, EWINIAR(0603) moved northwards and hit the Republic of Korea, causing damage to the country From late August to early September, convective activity was temporarily inactive over the sea east of the Philippines. However, it turned active again after late September. Subtropical high was weak over the south of Japan after late August. Therefore, most tropical cyclones formed over the sea east of the Philippines and moved northwards. WUKONG(0610) and SHANSHAN(0613) hit Japan to bring damage to the country. On the other hand, XANGSANE(0615) and CIMARON(0619) moved westwards in the South China Sea, causing damage to the Philippines, Thailand, and Vietnam. In addition, IOKE(0612) was the first namded cyclone formed in the central North Pacific and moved westwards across longitude 180 degrees east after HUKO(0224).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.3
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• pp.125-151
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• 2018

We grouped the names attributed to the seas surrounding the Korean Peninsula in maps published in two major Korean ocean and fisheries science journals over the period from 1998 to 2017: the Journal of the Korean Society of Oceanography (The Sea) and the Korean Journal of Fisheries and Aquatic Science (KFAS). The names attributed to these seas in maps of journal paper broadly were classified into three groupings: (1) East Sea and Yellow Sea; (2) East Sea, Yellow Sea, and South Sea; or (3) East Sea, West Sea and South Sea. The name 'East Sea' was dominantly used for the waters between Korea and Japan. In contrast, the water between Korea and China has been mostly labelled as 'Yellow Sea' but sometimes labelled as 'West Sea'. The waters between the south coast of Korea and Kyushu, Japan were labelled as either 'Korea Strait' or 'South Sea'. This analysis on sea names in the maps of 'The Sea' and 'KFAS' reveals that domestic researchers frequently mix geographical and international names when referring to the waters surrounding the Korean Peninsula. These inconsistencies provide the motivation for the development of a basic unifying guideline for naming the seas surrounding the Korean Peninsula. With respect to this, we recommend the use of separate names for the marginal seas between continental landmasses and/or islands versus for the coastal waters surrounding Korea. For the marginal seas, the internationally recognized names are recommended to be used: East Sea; Yellow Sea; Korea Strait; and East China Sea. While for coastal seas, including Korea's territorial sea, the following geographical nomenclature is suggested to differentiate them from the marginal sea names: Coastal Sea off the East Coast of Korea (or the East Korea Coastal Zone), Coastal Sea off the South Coast of Korea (or the South Coastal Zone of Korea), and Coastal Sea off the West Coast of Korea (or the West Korea Coastal Zone). Further, for small or specific study areas, the local region names, district names, the sea names and the undersea feature names can be used on the maps.

• Korean Journal of Remote Sensing
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• v.26 no.4
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• pp.421-437
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• 2010

Surface particulate organic carbon (POC) concentration estimated from Maximum Normalized Difference Carbon Index (MNDCI) algorithm using SeaWiFS data is used to determine spatial and temporal variations of the Changjiang Diluted Water (CDW) in the East China Sea. 10-year monthly POC concentrations (1997-2007) show clearly seasonal variations. Inter-annual variation of POC in whole and three different areas separated by standard deviation is not linearly correlated with the Changjiang River discharge that has decreased after 1998. To determine more detailed spatial and temporal POC variations, we used empirical orthogonal function (EOF) analysis in summer (Jun.-Sep.) from 2000 to 2007. First mode is spatially and temporally correlated with the area influenced by the Changjiang River discharge. Second mode is temporally less sensitive with the Changjiang River discharge but spatially correlated with north-south patterns. Relatively higher POC variations during 2000 and 2003 were shown in the southern East China Sea. These patterns during 2004 and 2007 moved to the northern East China Sea. This phenomenon is better related to spatial variations of wind-direction than the amount of Changjiang River discharge, which is verified from in-situ measurement.

• Atmosphere
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• v.18 no.3
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• pp.183-197
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• 2008

The purpose of this study is to summarize tropical cyclone activity in 2007. 24 tropical cyclones of tropical storm (TS) intensity or higher formed in the western North Pacific and the South China Sea in 2007. The total number is less than the thirty-year (1971~2000) average frequency of 26.7. Out of twenty four tropical cyclones, 14 TCs reached typhoon (TY) intensity, while the rest 10 only reached severe tropical storm (STS) and tropical storm (TS) intensity - four STS and six TS storms. The tropical cyclone season in 2007 began in April with the formation of KONG-REY (0701). From April to May, two TCs formed in the western North Pacific in response to enhanced convective activity there. From June to July, convective activity turned inactive over the sea around the Philippines and in the South China Sea, and the subtropical high was weak over the south of Japan. MAN-YI (0704) and USAGI (0705) moved northwestward and hit Japan, bringing serious damage to the country. After August, convective activity became enhanced over the sea east of the Philippines, and the subtropical high turned strong over the sea south of Japan. Many TCs, which formed over the sea east of the Philippines and in the South China Sea, moved westward and hit China and Vietnam. PABUK (0706), WUTIP (0707), SEPAT (0708), WIPHA (0712), LEKIMA (0714) and KROSA (0715) brought serious damage to some countries including China, the Philippines and Vietnam. On the other hand, FITOW (0709) and NARI (0711) moved northward, bringing serious damage to Japan and Korea. After HAIYAN (0716), all four TCs except FAXAI (0720) formed over the sea east of $140^{\circ}E$. Three typhoons among them affected Republic of Korea, MAN-YI (0704), USAGI (0705) and NARI (0711). Particularly, NARI (0711) moved northward and made landfall at Goheng Peninsula ($34.5^{\circ}N$, $127.4^{\circ}E$) in 1815 KST 16 September. Due to $11^{th}$ typhoon NARI, strong wind and record-breaking rainfall amount was observed in Jeju Island. It was reported that the daily precipitation was 420.0 mm at Jeju city, Jeju Island on 16 September the highest daily rainfall since Jeju began keeping records in 1927. This typhoon hit the southern part of the Korean peninsula and Jeju Island. 18 people lost their lives, 14,170 people were evacuated and US$ 1.6 billion property damage was occurred.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.221-221
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• 2017

• Proceedings of the KSRS Conference
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• v.2
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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.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.34
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• pp.109-131
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• 2007

This paper has focusing CheongHaeJin's maritime trading activities between Korea, China and Japan in the 9th century. In operation of CheongHaeJin which Chang BoGo was given a key role, CheongHaeJin creates three nation's wealth in triangular trade among Korea, China and Japan. And also, CheongHaeJin's contribution is considerable to the maritime trade development of Northeast Asia through establishing trading advance base in China and Japan, and organizing Shilla's people in China. Chang BoGo justified the control over small business groups of the west and south sea of Korea and the east and south sea of China by keeping pirates away His trade groups controlled foreign trade of three countries: Shilla, the Dang Dynasty of China and Japan. They connected Persia, India, Southeast Asia, and China. CheongHaeJin's key success factors of the maritime activities are summarized as follows; There is a possibility of searching that successful factor from the people of operator of CheongHaeJin. Based on oceanic adventurous spirit with character and progressive thinking could complete the rally of sea influence and composition of fleets. Secondly, the success factor is the excellent operational ability and leadership which learned in the Dang Dynasty of China. Thirdly, In 9th century, International political context was suitable for CheongHaeJin's construction and operation. Such political circumstances had given to CheongHaeJin remunerative position. Finally, Although central government could not maintain the sea traffic securities, Chang BoGo's ocean trading fleets guaranteed the safe fishing industry of people and security of sea traffic.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1995.10a
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• pp.62-65
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• 1995

Understanding the flow circulation is of primary importance for studies of marine ecology and Pollution protection etc. However the circulation in coastal area is complicated with various processes and can not be considered as forced only by tides. The coastal area off South China is now playing an important role in economic development in southeast Asia with Hong Kong, Macao, Guangzhou and other cities situated in its central part (Fig. 1). (omitted)

• Maritime Security
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• v.3 no.1
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• pp.115-140
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• 2021

The South China Sea is a significant maritime shipping route with abundant submarine and fishing resources. Over 40,000 ships pass through the South China Sea every year, constituting around 50% of global shipping and 66% of crude oil. In particular, 30% of Korea's import cargo and 90% of energy imports pass through this body of water. The US and China realized the significance of this sea area from early on and are embodying national interest through maritime security at the national strategic level by implementing the 'Indo-Pacific' and 'One Belt One Road' strategies, respectively. Such geopolitical conflicts are manifested in the 'freedom of navigation operations' by the US in the South China Sea. Despite its significance, there is a lack of studies in Korea on the freedom of navigation operations, and most previous studies only focus on analyzing international law and agreements. This article examines the origin and background of the strategic perception of the freedom of navigation operations and derives implications for the peace and security of the Korean Peninsula as the strategic competition between the US and China continues.