• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.2
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• pp.62-67
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• 2010

Swells occurred on the coast of the East Sea on February 24, 2008 caused a loss of three lives and also damaged several west coasts of Japan. The recent increase of swell intensity with number of accidents demands more accurate forecasting of swells in terms of time and location. The swells occurred in February 2008 are hindcasted using SWAN model to examine the accuracy of the model for future forecasting. The model results are compared with ReWW3 data as well as measurement wave data and specially, wave spectrum is analysed by comparing with observed spectrum at two wave stations located in the east coast of Korea. The SWAN model shows similar results with observation data in terms of significant wave heights and swell arrival time but the shapes of wave spectrum are different between model and in-situ measurement data. For further improvement of swell forecasting, more comparison and analysis with observed wave spectrum is necessary and wave directional spectrum data are required to study on the characteristics of swells in the East Sea.

• Journal of Species Research
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• v.13 no.3
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• pp.318-325
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• 2024

Bacterial communities residing on islands have a significant impact on the functioning and establishment of a unique isolated ecosystem. Notwithstanding, systematic research on the indigenous microbial resources of domestic islands has been lacking. In order to understand the biodiversity and potential bioresources, we conducted sampling in 2023 from coastal waters from various islands off the west coast of the Korean Peninsula, including Baengnyeongdo, Daebudo, Deokjeokdo, Jangbongdo, Yeonpyeongdo Islands, along with Somaemuldo Island along the south coast. The coastal seawater samples were used to unearth microbial resources through the standard dilution plating. In total, approximately 1,600 bacterial strains were isolated from the samples as single colonies and identified using 16S rRNA gene sequence analyses. Eighteen strains, exhibiting ≥98.7% 16S rRNA gene sequence similarity to bacterial species with validly published names but not previously reported in Korea, were categorized as unrecorded bacterial species in Korea. These unrecorded bacterial strains displayed phylogenetic diversity, representing three phyla, four classes, 9 orders, 13 families, and 18 genera. The unrecorded species were assigned to the classes Alphaproteobacteria (Aliiroseovarius, Kiloniella, Maritalea, Palleronia, and Roseobacter), Gammaproteobacteria (Aliamphritea, Aliivibrio, Enterovibrio, Francisella, Leucothrix, Pseudoalteromonas, Psychrobium, Shewanella, and Vibrio), Flavobacteriia (Aquimarina, Pseudofulvibacter, and Tenacibaculum), and Verrucomicrobiae (Roseibacillus). This study presents comprehensive descriptions of the taxonomic attributes of these unrecorded species, covering morphology, biochemistry, and phylogenetic position.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.239-246
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• 2009

To establish a database for artificial seed production of stone flounder Kareius bicoloratus, experiments were conducted to study the characteristics of spawning and fecundity of this species. Broodstocks were captured in the area of Gyeokryeolbiyeoldo, Chungnam, Korea in October 2003 and induced to natural spawning. The broodstock consisted of 12 females (34.5~51.0 cm total length and 540~2,200 g body weight) and 23 males (29.0~38.0 cm total length and 310~680 g body weight). Gonad development began in December and proceeded in the direction of the tail; measurements were made with the naked eye. The tank-held broodstock were reared for 3 months before spawning, which continued for 77 days from January 9 to March 27, 2004. Daylength during the spawning was recorded at the yearly shortest of 9.8~12.1 hours and the water temperature was maintained at $8.4{\sim}12.2^{\circ}C$. The total fecundity was 19,844,000 individuals, among which 15,433,000 individuals (77.8%) were produced during the mid-spawning period. The average bloating rate, egg-fertilization rate and hatching rate of the total number spawned reached 50.4%, 58.5% and 55.6%, respectively, and 93.8% of the hatched fry appeared normal. The number of total eggs in absolute fecundity per total length was proportional to both lengths, as was the number of total eggs in relative fecundity per total length. The number of total eggs in absolute fecundity per body weight was proportional to body weight as was the number in relative fecundity per body weight except that the number in relative fecundity per gram decreased after a peak in increased body weight at a certain point.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.186-194
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• 1998

Species composition and biomass of intertidal benthic algae were studied at the coast of Yonggwang Nuclear Power Plant area and its adjacent stations over 4 seasons (October 1995-August 1996), Of 68 species identified, 7 were Cyanophyta, 12 were Chlorophyta, 14 were Phaeophyta and 35 were Rhodophyta. The largest number of algal species (44) was found at Sangnok, the northernmost station of the study area, whereas the smallest number of species (15) was found from Tongho, ca. 13 km north of the power plant site. Number of species showed highest during the spring (44) and minimum was recorded in autumn (28). Biomass per unit area showed maximum in spring ($189.5\;g\;dry\;wt{\cdot}m^{-2}$ in average) and minimum in winter ($107.9\;g\;dry\;wt{\cdot}m^{-2}$ in average). Biomass values exhibited a wide range of variation among the stations, ranging from a low of $22.0\;g\;dry\;wt{\cdot}m^{-2}$ in annual average at Tongho to a high of $295.7g\;dry\;wt{\cdot}m^{-2}$ in average at Sangnok. Dominant species in biomass were Corallina pilulifera, Sargassum thunbergii, Gymnogongrus flabelliformis and Enteromorpha compressa. There have been little variation in the dominant algal species around the power plant site during the past 10 years and also these algae appeared throughout the west coast of Korea with higher frequency.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5_2
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• pp.176-185
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• 2010

This study aimed to clarify meanings of Palkyung(八景) in different regions which can be considered as the prototype of the region's cultural landscape and also to confirm the change process by pointing out landscape characteristics and finally, to provide a foundation for the regions to establish their own identities, so they could be provided against the changes from developments in other areas. The relationship between the characteristics of landscape values and the components of 32 Palkyung in 4 places those are Gogunsan, Wido, Gunsan and Byunsan under Saemankeum area have been analyzed and evaluated from operational point of view to clarify the structure of the landscape concept. Some important differentiation points would be the sunset of the West Sea, sailing boats and the sceneries related to fishing as they are in the West Sea Islands and the coastal regions; and it clearly reflects the local customs and the characteristics of the landscapes. Each of Gogunsan, Wido and Gunsan Palkyung has 2 distance views with 4km of visible area while Byunsan Palkyung has only 1; and it is considered that because it is mountain area. Most of the Byunsan Palkyung has close range views except for Seohaenakjo and there are around 4 close range views in other areas. There were 4 landscape dominated influence areas each in Gunsan and Byunsan, which means that there are comparatively more close to middle range views. Moreover, each region contains 2 to 3 views of psychological influence but as mentioned, Byunsan has only 1 view of psychological influence. Therefore it is very important and valuable thing to consider the scenic relationship, preservation and reconstruction of Palkyung when planning the project.

• Journal of the Korean GEO-environmental Society
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• v.16 no.4
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• pp.33-40
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• 2015

In the correlation formulas related to consolidation proposed at present, the analyzed areas are limited to certain overseas or domestic areas and in order to increase the number of data, experimental data of different areas are integrated and therefore in many cases application is difficult. In addition, models have been developed without clear statistic evaluation of the obtained data. Accordingly, this study divided the soft areas of the west coast into Hangang, Kumgang and Yeongsangang in order to maximally reduce uncertainty of the experimental data and performed normality test and regression analysis on the physical and dynamic characteristics. According to the analysis result, the compression index and the modified compression index had strong linearity and in all areas modified compression index and initial void ratio had closest correlation, followed by total unit weight, water contents and liquid limits. As for overconsolidation ratio with depth, the width of overconsolidation ratio was large when the depth was less than 5 to 6 m in all areas and when the depth was over 5 to 6 m, the ratio was constant.

• Economic and Environmental Geology
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• v.18 no.4
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• pp.321-329
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• 1985

The gravity measurement has been conducted at 113 stations with an interval of about 1km along the national road of about 120km running from Busangdong to Pohang through Waekwan, Daegu, Youngchun and Aankang. The subsurface geology and structure along the survey line is interpreted from Bouguer anomaly by applying Fourier method and Talwani method for two dimensional body. The mean depth of Moho discontinuity is 31.4km, and the depth decreases very slowly from inner continent toward east coast. The depth of Conrad discontinuity increases from 11km at the east coastal area to 17km at the inner continental area, and especially increases rapidly in the area between Waekwan to Busangdong. The depth of basement of Kyoungsang Basin inereases from near Waekwan toward Daegu upto about 4. 8km, and increases rapidly to reach the maximum depth of about 8.5km at 8km east of Daegu. But it starts to decrease from the place of 10km west of Youngchun, and is about 7.2km at Youngchun and about 6km at 6km east of Youngchun. The depth starts to increase smoothly beyond this point, and is 7km at 15km east of Youngchun. From this point, the depth starts to decrease again, and is about 3.8km at Ankang. The depth of basement of Pohang Basin is 500m at Pohang and about 650m at 5km west of Pohang. A massive granite body which is considered to be a part of Palgongsan Granite exposed at the depth of 1. 5km at 9km west of Youngchun. Another massive granite body is situated underneath the Pohang Basin at depth of 1.5 to 2km, and sedimentary rocks of Kyoungsang Group and volcanic rocks are distributed between Pohang Basin and this granite body. Finally, Yangsan Fault is identified at about 2.5km east of Ankang.

• Journal of Environmental Science International
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• v.13 no.11
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• pp.965-985
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• 2004

The investigation of driving mechanism for the formation of tropical night in the coastal region, defined as persistent high air temperature over than 25$^{\circ}C$ at night was carried out from August 14 through 15, 1995. Convective boundary layer (CBL) of a 1 km depth with big turbulent vertical diffusion coefficients is developed over the ground surface of the inland basin in the west of the mountain and near the top of the mountain, while a depth of thermal internal boundary layer (TIBL) like CBL shrunken by relatively cool sea breeze starting at 100 km off the eastern sea is less than 150 m from the coast along the eastern slope of the mountain. The TIBL extends up to the height of 1500 m parallel to upslope wind combined with valley wind and easterly sea breeze from the sea. As sensible heat flux convergences between the surface and lower atmosphere both at the top of mountain and the inland coast are much greater than on the coastal sea, sensible heat flux should be accumulated inside both the TIBL and the CBL near the mountain top and then, accumulated sensible heat flux under the influence of sea breeze circulation combined with easterly sea breeze from sea to inland and uplifted valley wind from inland to the mountain top returning down toward the eastern coastal sea surface should be transported into the coast, resulting in high air temperatures near the coastal inland. Under nighttime cooling of ground surface after sunset, mountain wind causes the daytime existed westerly wind to be an intensified westerly downslope wind and land breeze further induces it to be strong offshore wind. No sensible heat flux divergence or very small flux divergence occurs in the coast, but the flux divergences are much greater on the top of the mountain and along its eastern slope than on the coastal inland and sea surfaces. Thus, less cooling down of the coastal surface than the mountain surface and sensible heat transfer from warm pool over the coast into the coastal surface produce nocturnal high air temperature on the coastal inland surfaces, which is not much changed from daytime ones, resulting in the persistence of tropical night (nocturnal thermal high) until the early in the morning.

• Korean Journal of Ichthyology
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• v.7 no.1
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• pp.56-63
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• 1995

Ecological study of the Cynoglossus joyneri was conducted based on the specimens from the western coast of Korea from 1992 to 1994. Ecological characteristics of this species such as gonadal development, occurrence of larvae, stomach contents, and environmental conditions were investigated. Few larvae of Cynoglossus joyneri occurred in Kunsan coast. This coast is influenced by the freshwater input of the Mangyong and Kum River, especially during the summer. Therefore, the larvae of C. joyneri were considered to be spawned and grown during their early life stage in the high saline water in outer bay. Spawning occur from June to September, having the peak spawning period from July to August. Biological minimum size of matured fishes containing mature oocytes is about 143.5mm in total length, which requires about 20 months after hatching. The ranges of total length by age are as follows : 0-ring group(floating stage), 30~70mm ; 1-ring group, 49.0~133.0mm 2-ring group, 128.6~167.0mm ; 3-ring group, 169.0~202.0mm ; 4-ring group, 200.7~240.0mm. The major food items of young fish under 8cm were copepods and invertebrate larvae, and those of adult fishes were annelids(polychaets) in winter, and bivalves and shrimps in summer and autumn. Therefore, it can be assumed that the population of C. joyneri could be reduced due to the decrease of food organisms caused by the continuous reclamation activities in the inner bays of the west coast of Korea.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.529-539
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• 1997

The circulations and movement of suspended materials by tidal residual current and seasonal surface wind in the Yellow Sea and the East China Sea are investigated by using a 2-dimensional barotropic model and a particle tracing technique. The tidal residual current is relatively strong around the south and west coast of Korea including the Cheju Island and southern coast of China. The current has a maximum speed of 10 cm/s in the vicinity of Cheju Island with a clockwise circulation. General tendency of the current, however, is to flow eastward along the southern coast of Korea. At the east coast of China from Shanghai to Tunghai, it also shows a eastward flow toward the South Sea of Korea. The anticyclonic circulation formed by wind-driven current and southward current prevails along the coast of Korea in the winter season(from October to April) when northerly wind is dominant. In summer(represented by July), however, the cyclonic circulation appears due to the influence of southerly wind. Suspended materials are advected by tidal residual current and wind-driven current. The long period(ten days) displacement by wind-driven current is bigger than that by tidal residual current. However, the tidal residual current would have the more important role for the advection of the suspended material considering longer period more than several months.