• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권4호
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• pp.249-253
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• 2000

Data obtained from a cruise from 4~12 December, 1998 was analyzed to estimate the mixing effects of wind, surface cooling, and tide. A band denoting a mixing area with a temperature difference of less than 1$^{\circ}C$ between the sea surface and the bottom extended 40~60 km from the coast into the open sea, following 125$^{\circ}$ 30\` E in longitude. This band was divided into two areas; a well-mixed area close to the coast and a stratified region in the open sea. The mixing effect due to the wind was only 2%, yet the mixing effect due to the tides was about 68%. This indicates that surface cooling and tides were the major factors involved in the mixing mechanism on the west coast during the cooling season.

• Journal of Environmental Science International
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• 제14권1호
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• pp.41-51
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• 2005

Using three-dimensional non-hydrostatical numerical model with one way double nesting technique, atmo­spheric circulation in the mountainous coastal region in summer was investigated from August 13 through 15, 1995. During the day, synoptic westerly wind blows over Mt. Mishrung in the west of a coastal city, Sokcho toward the East Sea, while simultaneously, easterly upslope wind combined with both valley wind from plain (coast) toward mountain and sea-breeze from sea toward inland coast blows toward the top of the mountain. Two different directional wind systems confront each other in the mid of eastern slope of the mountain and the upslope wind goes up to the height over 2 km, becoming an easterly return flow in the upper level over the sea and making sea-breeze front with two kinds of sea-breeze circulations of a small one in the coast and a large one in the open sea. Convective boundary layer is developed with a thickness of about 1km over the ground in the upwind side of the mountain in the west and a thickness of thermal internal boundary layer from the coast along the eastern slope of the mountain is only confined to less than 200 m. On the other hand, after sunset, no prohibition of upslope wind generated during the day and downward wind combined with mountain wind from mountain towardplain and land-breeze from land toward under nocturnal radiative cooling of the ground surfaces should intensify westerly downslope wind, resulting in the formation of wind storm. As the wind storm moving down along the eastern slop causes the development of internal gravity waves with hydraulic jump motion in the coast, bounding up toward the upper level of the coastal sea, atmospheric circulation with both onshore and offshore winds like sea-breeze circulation forms in the coastal sea within 70 km until midnight and after that, westerly wind prevails in the coast and open seas.

• Journal of the Korean earth science society
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• 제37권2호
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• pp.89-106
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• 2016

The Gochang open-coast intertidal flat is located in the southwestern coast of Korea (the eastern part of the Yellow Sea), characterized by macro-tidal range, an open-coast type, and sand substrates. This study has investigated seasonal variation in sedimentary facies of surface sediments in the Gochang intertidal flat. In the four seasons of February, May, August, and November, 2014, surface sediments of 252 sites in total were sampled and analyzed along three survey lines. The surface sediments of the Gochang intertidal flat in 2014 consisted mainly of fine-grained sand sediments showing a trend in grain size to be coarser in winter and finer in summer. Based on seasonal wave and tidal level data recorded near the study area, it was interpreted that the seasonal effects of wave were stronger than those of tide as a factor controlling surface sedimentation. High waves in winter resulted in the coarsening trend of grain size in surface sediments, whereas, during summer time, the sediments became finer by relatively low waves. Spatial sedimentary facies of the Gochang intertidal flat in 2014 represented that seasonal deviation of the upper tidal zone was larger than that of the lower tidal zone, hence sediments getting coarser in grain size and poorly sorted in the upper tidal zone. From upper to lower tidal zone, the grain size became finer and sediments were better-sorted, showing smaller seasonal deviations.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.630-634
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• 2007

In the past, the use of wave energy has mainly been focused on conversion of large wave energy resources in the far offshore areas. However, with the technological improvement of converting wave energy into electricity, the energy resources at much shallow waters are now considered as a site for possible installation of the devices that obtain energy from the waves. In this respect, the wave energy resources on the east coast of Korea, where the sea is milder than the open ocean, were investigated using the field measurement data obtained at three different locations along the coast. For all the locations, the wave power was greater in winter season, compared to summer season. The estimated wave power varied from 2 to 4.5 kW/m on average, depending on the measurement locations.

• Journal of the Korean Society for Railway
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• 제8권5호
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• pp.405-410
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• 2005

In this paper, the train resistances for HSR-350x(Korean High Speed Train project), which has been obtained by the coast-down test, have been proposed in cases of the open field and tunnel. They are approximated as quadratic functions suggested by the Davis equation. The coast-down simulations for HSR-350x using the estimated train resistances have performed and the results have been compared with those of the same conditions of the coast-down tests. It is concluded that the proposed train resistances can be considered to provide good estimations for HSR-350x. Also, the effects of the infrastructure conditions, such as tracks, curves and tunnels have been reviewed. These results show that the tunnel plays an important role in determining the train resistance but others does not.

• Journal of the Korean earth science society
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• 제36권6호
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• pp.533-542
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• 2015

The Gochang beach is located in the southwestern coast of Korea along the eastern part of the Yellow Sea, comprising the Donghori, Gwangseungri, and Myeongsasipri beaches from north to south. The Gochang beach is characterized by macro-tide, open-coast, linear shoreline, and sand substrates. This study has investigated annual and seasonal characteristics of surface topography variation and sediment accumulation rate in the Gochang beach. During the five seasons of winter (Feb.), spring (May), summer (Aug.), and fall (Nov.) in 2014 and winter (Feb.) in 2015, the topographic elevation of total 315 sites was measured along three survey lines. It consists of 21 sites at 30 m intervals in each transverse line perpendicular to the shoreline, respectively. Annual accumulation rate of the Gochang beach in 2014 was -0.081 m/yr, indicative of erosional condition. Annual accumulation rates of the comprising beaches represent -0.091m/yr of the Donghori, -0.051 m/yr of the Gwangseungri, and -0.10 m/yr of the Myeongsasipri.

• Journal of the Korean Society of Marine Environment & Safety
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• 제18권5호
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• pp.379-387
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• 2012

In order to see the oceanographic conditions, the observations of aquaculture farm of ascidian in Youngdeuk, the east coast of Korea were conducted through 6 times-23 February, 6 April, 8 June, 19 August, 6 October and 20 December-in 2010. Surveys were conducted in 20 stations bimonthly using SBE 19 CTD instrument. The mixed layer depth (MLD) was deep in winter and shallow in summer. The cold water below $5^{\circ}C$ in temperature was occupied below thermocline through all season. The temperature was high in the southeastern area. The salinity was increased from the coast to the open sea. The halocline was distinct at 20 m depth in August and at 40 m depth in October. The lowest value of salinity was appeared at the depth of 10 m in October. In addition the value of precipitation minus evaporation denoted negative in October. These low saline water seemed to inflow to the coast from the open sea. Therefore the low saline water moved to the east coast of Korea. The EKWC may play an important role to convey the low saline water. It may affect the aquaculture farm along the coast as the mass mortality of ascidian. It needs to clarify the role and pathway of EKWC to transfer the low saline water along the east coast of Korea.

• Journal of the Architectural Institute of Korea Planning & Design
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• 제35권6호
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• pp.59-68
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• 2019

The purpose of this study was to analyze the spatial change of coastal area called Nampo-dong in Busan. And then the subject of research was chiefly concentrated upon the development of southern coast and the land-reclamation based on the commercial facilities after the opening port. There were various reclamation projects in the coastal area of Japanese settlement under the Rule of Japan. Busan Nambin Coast(Currently, Nampo-dong) was one of typical reclamation projects conducted in the southern seashore. Due to the characteristic of coastal area, fishery was developed well and the entertainment industry also grew rapidly with the characteristic of the short distance of urban centre. In this study, we investigated the process of reflecting the characteristic of spatial change that were pursued by communities at that time, particularly through the establishment and change of buildings.

• Journal of the Korean association of regional geographers
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• 제22권4호
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• pp.875-886
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• 2016

The eastern coast of Seopo-myeon, Sancheon-si in the South Coast is a bay almost completely separated from open sea by Changseon and Namhae Islands. Marine terraces in this area can be classified into geomorphic surfaces with elevations of 10~12m, 15~18m, 20~24m, 25~28m, 30~33m, 35~38m, 40~45m, 45~50m and 54m. This marine terrace system is similar to the Boryeong area in the West Coast. The geomorphic surfaces distribute along ridges and show relatively small areas. The young and old surfaces show a mixed distributional pattern. This distributional pattern contrasts to the East Coast where the oldest surface farthest from the coastline is parallel to the coast and age of the surfaces increases with a distance from the coast. These seem to result in high energy waves by typhoon that developed wave-cut platform on hill areas with relatively complex relief in a short time.

• Fisheries and Aquatic Sciences
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• 제24권7호
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• pp.243-259
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• 2021

The spatial and temporal behaviors and fluctuations of the cold water that appeared in the South East Sea and the East Sea coast from 2016 to 2017 were investigated. The water temperature drop was large in the east coast from April to June and the southeast coast from July to September, and the temperature drop period was longer in the southeast coast. The water temperature fluctuated sensitively to the wind direction, and it gradually decreased in the southwest wind but rose as if jumping in the northeast wind. Wind stress and surface water temperature had an inverse correlation, which was larger in Bukhang-Idukseo, and decreased toward the north of Guryongpo. The cold water appeared mainly in Geojedo-Pohang after 1 to 2 days when the southwest wind was strong, but when the wind became weak, it shrank to the Idukseo (Ulgi-Gampo) and extended into the open sea in a tongue shape. Cold water was distributed only in Samcheok-Toseong in mid-May, Idukseo-Guryongpo and Hupo-Jukbyeon-Samcheok from late May to mid-July, and Bukhang-Idukseo in August-September. The intensity of cold water was greatest in mid-August, and the center of cold water descended from the east coast to the southeast coast from spring to summer. The water temperature fluctuation was dominant at the periods of 1 d and 7-21 d. In wavelet spectrum analysis of water temperature and wind, wind speed increase-water temperature decrease showed phase difference of 12 h in 2 d, 18 h in 3 d, 1.5 d in 4-8 d, and 2-3 d in 8-24 d period. The correlation between the two parameters was large in Geojedo and Namhang, Bukhang-Idukseo, Guryongpo-Jukbyeon, and Samcheok-Toseong. Monitoring stations with high correlation in all periods were generally parallel to the monsoon direction.