• Atmosphere
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• v.21 no.4
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• pp.439-446
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• 2011

NCEP reanalysis data were analyzed in order to provide distribution of global wind resource and wind speed in the surface layer for the years 2000-2009. Wind speed at 10 m above ground level (AGL) was converted to wind speed at 80 m above the ground level using the power law. The global average 80 m wind speed shows a maximum value of $13ms^{-1}$ at the storm track region. High wind speed over the land exists in Tibet, Mongolia, Central North America, South Africa, Australia, and Argentina. Wind speed over the ocean increased with a large value in the South China Sea, Southeast Asia, East Sea of the Korea. Sea surface wind in Western Europe and Scandinavia are suitable for wind farm with a value of $7-8ms^{-1}$. Areas with great potential for wind farm are also found in Eastern and Western coastal region of North America. Sea surface wind in Southern Hemisphere shows larger values in the high latitude of South America, South Africa and Australia. The distribution of low-resolution reanalysis data represents general potential areas for wind power and can be used to provide information for high-resolution wind resource mapping.

• Asian Journal of Atmospheric Environment
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• v.5 no.4
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• pp.216-227
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• 2011

A Sea breeze front (SBF) appears clear particularly if there is opposing wind, and the convergence zone along a SBF affects air quality in coastal areas. This study analyzes features of SBF separation in the presence of an opposing flow in the southeastern coastal area of Korea Peninsula. Using a Regional Atmospheric Modeling System (RAMS) numerical simulation and an opposing flow, two types of SBF were observed at Masan coastal area of Korea. In one, the SBF penetrated inland despite of the opposing flow at Jinhae (1100 LST), Wondong (1700 LST), Saenglim (1700 LST), and Miryang (1700 LST). In the other, the SBF remained on the coastline along with Jinhae (1100 LST), Masan (1400 LST), Jinbuk (1400 LST), and Gaecheon (1700 LST), because the inflow of the sea breeze was not sufficient to penetrate inland against the opposing flow. This study shows that SBFs are affected by the formation of an opposing flow, as well as the inflows of a sea breeze and the opposing flow.

• 한국해양학회지
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• v.11 no.2
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• pp.77-88
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• 1976

The water movements in the south sea of Korea are deduced from the distributions of water properties. In summer the flow path of the Tsushima Current is deflected off from the Korean coast; between the coast and the current there exist eddies. Cyclonic eddies are particularly dominant in the southeastern area of Sorido Is. In winter, the sunken coastal water flows out along the bottom toward the southeast, and compensation is made at the surface by the coastward intrusion of off-shore waters. The so-called coastal counter- current of the area seems to be a cyclonic eddy which prevails in summer and autumn.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.353-358
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• 2011

This study is the result of examining the growth and survival rate of larva and spat when supplied with Enriched live food by adding $B_{12}$, chitosan, PSB, and polysaccharides to microalgae (Chaetoceros gracilis, Isochrysis galbana) to raise the survival rate of larva and spat during artificial clam seed production. Microalge (Chaetoceros gracilis, Isochrysis galbana) was strengthened for nutrition with $B_{12}$ 0.1 ppm, chitosan 0.2 ppm, PSB 3 ppm and polysaccharides 1 ppm and was daily supplied for $3{\times}10^3-15{\times}10^3Cells/mL$ and the growth and survival rates were measured. As the result of experiment, the growth of larva did not show much difference with PSB test section $199{\pm}0.59{\mu}m$, $B_{12}$ test section $198{\pm}0.64{\mu}m$, and chitosan $197{\pm}0.52{\mu}m$, survival rate was highest at PSB test section with 99.3%, followed by $B_{12}$ test section 95.9%, and chitosan 94.5%. Growth of early spat was the highest for PSB test section at $2.74{\pm}0.58mm$, followed by polysaccharides $2.67{\pm}0.55mm$, $B_{12}$ $2.54{\pm}0.48mm$, and chitosan $2.49{\pm}0.51mm$, and the survival rate was the highest for PSB test group at 32.1%, followed by $B_{12}$ test section 31.6%, chitosan 28.5%, and polysacharrides 21.4%. From such results, PSB is found to be very effective with low-quality improvement when breeding early spat of clams, and especially for floor-type early spat breeding, it had the effect of suppressing protozoan and germs so that detailed studies from various perspectives should be conducted with various chemicals in the future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.366-371
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• 2011

The sea squirt Halocynthia roretzi is mainly cultured in Tongyeong, Southern coastal area of Korea. This study presents the physiological rates of respiration, excretion, feeding and assimilation efficiency of the sea squirt Halocynthia roretzi to analyze the SFG(scope for growth) and net growth efficiency, determined during 2007. Oxygen consumption and nitrogen excretion rates increased with a rise in temperature during the summer period whereas feeding rates decreased. The O:N ratio was high during winter(October to February). Assimilation efficiency showed an annual average of 75.4% during the experimental period, except during a period of elevated temperature in July to September(average $25^{\circ}C$). Net growth efficiency($K_2$) was 8.7 to 64.2% except for May to September, when temperature increased at the aquaculture farm. SFG was negative from May to September, reflecting high temperatures and low feeding rates during this period; its highest positive values occurred during winter.

• Journal of the Korean earth science society
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• v.26 no.6
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• pp.541-550
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• 2005

Molluscan shells were sampled from the continental shelf of South Sea: 19 stations in the southeast continental shelf and 5 in the southwest sea, in order to understand characteristics of sea level changes and time-averaging since the last glacial age. Radiocarbon dates were made on 42 dominant and specific species which were sampled from 24 stations. Time-averaging was observed and showed to be 11,939 years in age difference. The sea-level ranged from 150 to 160 m below sea level during the LGM (about 15,000 yrs B.P). The sea-level significantly rose to 60 m at around 9,000 yrs B.P. and became stable at 50 to 60 m between periods between 4,000 and 5,000 yrs B.P. Between 3,000 and 4,000 yrs B.P, the sea-level rapidly rose to a depth of $10\~20m$ below today’s present sea level.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.370-378
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• 2012

This study is to find out the distribution characteristic of Octopus minor in the Tando Bay on the southwest coast of Korea with conducting surveys from May of 2006 to April of 2007. Surveys were carried out at 20 stations on 2 and 3 tide time in the low speed of high tide at night and conducted during 30minutes (4 times fishing) per station. Catch per unit effort (CPUE) was estimated by total catch per 500hooks at each station. Monthly CPUE showed that they put highest in October, November, April and June at 10.4, 10.5, 9.4 and 7.7 individuals respectively. On the other hand, CPUE put lowest in January, the coldest month, and August, the hottest month, at 0.2 and 0.3 individuals respectively. As for geographical mantle length distribution, average mantle length ranged from 6.2cm to 7.3cm at stations near the tidal channels (St. 1, 4, 5, 6, 8, 9, 10, 13, 14, 15, 18, 19 and 20), and was smaller than 6.0cm at stations located inside of bay (St. 2, 3, 7, 11, 12 and 17). In terms of geographical distribution density, CPUE showed higher than 8.0 at St.4 in Changmaeri, St.8 in Taecheonri, St.13 near Seondo, St.18 in Naeri and St.14 in western part of Tando which are located near the main tidal channels. And distribution density showed low that CPUE was lower than 5.0 individuals at stations located inside of bay (St. 1, 3, 5, 6, 7, 11, 12, 16 and 20). Through the results, the difference of distribution density reflects that distribution of Octopus minor is affected by direction of current and inflow of pollutant from land in direct. Therefore, it is considered that bottom composition of tidal flat and distribution of live food are the crucial cause of identifying the distribution characteristics of Octopus minor. For this reason, it is judged to need additional research on it.

• The Southeast Asian review
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• v.28 no.4
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• pp.31-76
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• 2018

This article explores why the two Southeast Asian countries, Vietnam and the Philippines, choose different strategies to cope with the Chinese threat. Despite the evident Chinese threat in the South China Sea, Vietnam has not meaningfully expanded the military cooperation with the United States, whereas the Philippines, ironically, has distanced itself with its ally, the United States. Existing studies on the topic does not offer a satisfactory explanation. We assign that two cases are examples of "underbalancing" - the failure of balancing even though there is an evident threat. Furthermore, we demonstrate the difference between cases of the Philippines and Vietnam by arguing that the number of veto players affects the outcome of foreign policy, underbalancing of two countries. The Philippines has only one veto player, the president, hence its response to external threats is incoherent. On the other hand, the number of veto players in Vietnam is more than one and those players demand negotiation among them on the matter of foreign policy. Upon analyses on two cases we argue that the former is the case of underbalancing caused by a lack of policy stability, while the latter is the case of underbalancing caused by a lack of policy responsiveness.

• 한국해양학회지
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• v.1
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• pp.16-24
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• 1971

Over 40 bottom sediment samples were collected from the southern sea of Korea. The detailed textural characteristic of the sediments, percent calcium carbonate and heavy and light mineralogy were determined. Seaward of these sediments is a nearly broad belt of sandy sediments. In a broad outline it is considered to constitute a near-shore deposits left from a Pleistocene time of eustatically lowered level of sea water, because the sediments on the outer half of the continental shelf are much coarser than that nearer shore. The carbonate content increases strongly to the southeast and northwest of Cheju Island. It is believed that the high calcium carbonate content can be largely attributed to the availability of carbonate materials.

• Journal of the Korean Geophysical Society
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• v.9 no.3
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• pp.249-262
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• 2006

The 29 May 2004 offshore Uljin, Korea earthquake was predominantly thrust-faulting at a depth of approximately 12 (±2) km. The mainshock attained the seismic moment of M0 =5.41 (±1.87)  1016 N m (Mw = 5.1). The focal mechanism indicates a subhorizontal P-axis trending 264° and plunging 2°. The orientation of P- and T-axis is consistent with the direction of absolute plate motion generally observed within the plates, hence the cause of the May 29 shock is the broad-scale stress pattern from the forces acting on the downgoing slab along the Japan trench and inhibiting forces balancing it. The 29 May 2004 earthquake occurred along a deep seated (~12 km), pre-existing feature that is expressed on the surface as the basement escarpment along the western and southern slopes of the Ulleung basin. The concentrated seismicity along this basement escarpment suggests that this feature may qualify as a seismic zone - the Ulleung basement escarpment seismic zone (UBESZ).