• 한국해양학회지
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• v.19 no.1
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• pp.24-30
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• 1984

A numerical experiment was carried out on thee wind-induced coastal upwelling along the east coast of Korea. Only the variability in coastline geometry is considered and an attempt is made to correlate it with the observation previously performed. In order to approximate the coastline geometry as closely as possible, the finite element method with linear triangular grid is employed. Among several fixed locations of upwelling center found in the model, the one in the southeastern coastal area seems to be just what has been observed most frequently.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1392-1394
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• 2003

This paper presents the actual test data of 3 phase, 9 pole, 3.6 [kw] synchronized wind-power generator controlled by hinged vane system and the possibilities of the small mount wind-power generations at the south-east coast of Ul-san. It also shows the data of the wind-velocity acquired by wind-direction sensor, calculation and analysis of the estimated electrical generation power, energy storage systems, and the efficient usages of the wind-power system.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.429-435
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• 2019

The drifters of the Global Drifter Program were deployed in the northern East Sea for two years from March 2015 to compare and validate currents estimated from sea-level measurements with the SARAL/AltiKa altimetry satellite mission, specially designed to accurately measure sea level in the near-coastal area. The collocated (less than 20 km apart) directly measured current from GPS locations every 30 minutes and the currents normal to the satellite tracks show a similar correlation in the area shallower than 200 m depth as the open ocean and it makes it possible to investigate the time variations of the current along the coast in the northern East sea, where direct observations of current are scarce. The Liman Current along the Siberian coast is found to be southward all year round, but the North Korean Cold Current flows southward only in the summer. The North Korean Cold Current south of the Musudan cape mostly flows to the south, but the current direction depends on the presence of an eddy around the coast of Musudan cape.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.3
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• pp.166-178
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• 2015

We investigated marine environmental characteristics of Goheung coastal areas in August where is known to be the first outbreak site of Cochlodinium polykrikoides (hereafter C. polykrikoides) blooms, based on the oceanographic data observed from 1993 to 2013 around the Korean southern coastal waters including Eastern China Sea by National Fisheries Research and Development Institute (NFRDI). The data of NOAA/NGSST satellite images as well as numerical simulation results by Seo et al. [2013] were also used for analysis. Water temperatures at the surface and bottom layers in Goheung coast, i.e. Narodo, were $25.0^{\circ}C$ and $23.7^{\circ}C$ so that they were higher than $23.8^{\circ}C$ and $19.4^{\circ}C$ in Geoje coast where is a reference site, respectively. In addition, salinities at the surface and bottom layers in Goheung coast were 31.78 psu and 31.98 psu so that they were a little higher than 31.54 psu at the surface but a little lower than 32.79 psu at the bottom in Geoje coast, respectively. That is, the differences in water temperature or salinity between the surface and bottom layers in Goheung coast in August were not large compared to Geoje coast. This suggests that stratification in Goheung coast in August is fairly weak or may not be established. In addition, the concentrations of DIN and DIP at the surface layer were 0.068 mg/L ($4.86{\mu}M$) and 0.015 mg/L ($5.14{\mu}M$) in Goheung coast while 0.072 mg/L ($5.14{\mu}M$) and 0.01 mg/L ($0.32{\mu}M$) in Geoje coast, so they did not indicate a meaningful difference. On the other hand, when C. polykrikoides blooms, water temperature and salinity in August at the station 317-22 ($31.5^{\circ}N$, $124^{\circ}E$) of the East China Sea, where is near the mouth of Yangtze River, were $27.8^{\circ}C$ and 31.61 psu, respectively. Thus, water temperature was much higher whereas salinity was almost similar compared to Goheung coast. Furthermore, concentrations of $NO_3-N$ and $PO_4-P$ in the East China Sea in August were remarkably high compared to Goheung coast. When C. polykrikoides blooms, according to not only the image data of satellites NOAA/NGSST but also numerical experiment results by Seo et al.[2013], the freshwater out of Yangtze River was judged to clearly affect the Korean southern coastal waters. Therefore, the supply of nutrients in terms of Yangtze River may greatly contribute to the outbreak of C. polykrikoides blooms in Goheung coast in summer.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.2
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• pp.154-161
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• 2014

Maturity and spawning of the giant Pacific octopus, Octopus dofleini was investigated based on the samples collected in the coast of Gangwondo, East Sea, from January to December in 2009. Individuals of mature stage had a higher occurrence rate from February to May, and gonadosomatic index (GSI) also showed a higher value from February to May than the other months. For that reason, the spawning period was estimated from February to May with the main spawning period from March to May. The total number of eggs in the fecundity (F) ranged from 9,045 in 11.0 kg (TW) to 148,682 in 16.5 kg (TW), which was proportional to total weight (TW), and the relationship between total weight and fecundity was $F=0.185{\times}TW^{2.238}$ ($R^2=0.389$). The total weight at 50% group maturity (TW0.5) of female was estimated to be 12.2 kg.

• Journal of the Korean Society of Marine Environment & Safety
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• v.1 no.2
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• pp.53-60
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• 1995

We measured lagrangian currents in the coastal regions off east coast of Korea. The experiment sites are the Ulijin region where Polar Front of the East Sea is formed and the Ulgi region where coastal upwelling occurs frequently in summer. Each drifters are equipped with GPS receiver, and their trajectories are montiored by receiving the data transmitted from drifters through radio signal. The experiment with 'transmitting' GPS is very useful in monitering flows in coastal regions. Trajectories of drifters in the Uljin Polar Front region in October 1994 showed counterclockwise flow pattern. The flow pattern agrees with the SST distributions obtained from NOAA-11 AVHRR image for the same period. The lagrangian trajectories of drifters at 5m and 15m depths in the Ulgi region for normal period of April 1995 showed that the currents at the top 15m layer are almost uniform and their magnitude is 29cm/s. However, the currents, measured by KORDI, during the upwelling period of June 1994 showed that the currents at 5m depth were 1.2 times stronger than those at 15m depth. The current pattern in the Ulgi upwelling region agrees with the horizontal and vertical distributions of seawater temperature measured by NFRDA at the same period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.426-434
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• 2018

We investigated temporal and depth-related variation in species composition and abundance of the fish assemblage in the southern East Sea. Fish samples were collected seasonally between 2007 and 2008 using a demersal trawl off the southern coast of Korea. We identified 59 fish species belonging to 41 families. The most frequently occurring species was Coelorinchus multispinulosus, followed by Lophius litulon, Acropoma japonicum and Apogon lineatus. The five most abundant species were A. lineatus, A. japonicum, Myctophum nitidulum, Engraulis japonicus and C. multispinulosus, accounting for 87.04% of the total number of individuals collected. The number of species, abundance and diversity fluctuated with sampling location and time. Permutational multivariate analyses of variance revealed that the assemblage structure was influenced by year, season and water depth, with season being the main indicator. These changes were visually emphasized using non-metric multidimensional scaling ordination plots. Fluctuations in assemblage structure were due to differential contributions of the dominant species.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.4
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• pp.404-412
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• 1994

On July 12. 1993 at 22 : 17 local time (-9h. KST). an earthquake of surface magnitude (MS) 7.6 occurred on the west coast of the Hokkaido and small of offshore island of Okushiri in the East Sea. A major tsumani was generated and within 2 to 5 minutes, extremely large tsunami waves engulfed the Okushiri coastal area and the central west roast of the Hokkaido. This tsunami caused tremendous casualities and damage. A giant tsunami runup of more than 30 m in height was recorded. The tsunami crossed the East Sea and feeled at 27 sites of the eastern Korean coast during the survey on 17-19, July, 1993. The observed tsunami runup at southern part of the eastern Korean coast were generally weaker than the 1993 Japan Sea Central Earthquake tsunami and varied from 0.8 m to 2.6 m. The Present Paper intends to understand the propagation on this tsunami with the aid of numerical computation model andd computer graphic aided video animation.

• Journal of Environmental Science International
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• v.19 no.4
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• pp.399-406
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• 2010

Based on the Results of Annual Monitoring Report of Korean Marine Environment in 2006, it was shown that the coastal area of the East Sea around Korean peninsula could be clearly divided into two parts: the area of upwelling and the North Korean Cold Current. In the upwelling area, the chlorophyll-a and nutrients were increased by the influence of the decrease of temperature and the increase of salinity. These mean that the appearance of cold water due to the upwelling causes nutrient rich water and also resulted in the high productivity.

• Journal of Environmental Science International
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• v.24 no.5
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• pp.615-622
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• 2015

East Asia is characterized by anthropogenic emissions resulting from the large population and fast economic growth of this region. Since the prevailing wind is westerly and northwesterly, emissions from Ul-jin can be expected to contribute to acidic deposition increase in downwind direction. Aerosols collected at the near coast site, Uljin geun, gyungbook and were analyzed for $NH_4{^+}$, $Mg^{2+}$, $Na^+$, $Ca^{2+}$, $Cl^-$, $SO_4{^{2-}}$, and $NO_3{^-}$ from Aug. 2012 to Feb. 2013. The seasonal averaged aerosol concentration showed the highest potassium and calcium ion in winter and the highest ammonium ion due to a meadow and high solar intensity in summer. Sodium and chloride ion showed the same ratio all seasons and sulfate and nitrate species showed the maximum value in winter Chemical components of aerosols collected at the near coast site, Uljin geun, gyungbook were lower by 16 to 73% than those collected at other similar environment site such as kanghwa, yangyang. Comparing air quality data at the near coast site, Uljin geun, gyungbook, There was found that Uljin coast site is less influenced by the sea salts(potassium, magnesium, calcium) and nss-$SO_4{^{2-}}$ percentage is 3~13% higher than similar condition site.