• Title/Summary/Keyword: 용승

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Correlation Analysis of UA Using Wind Data of AWS/ASOS and SST in Summer in the East Sea (AWS/ASOS 바람자료를 이용한 여름철 동해 연안역의 용승지수와 수온과의 상관성)

  • Kim, Ju-Yeon;Han, In-Seong;Ahn, Ji-Suk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.6
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    • pp.773-784
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    • 2018
  • In this study, we examined the UA (upwelling age) using wind data of AWS/ASOS in the East Sea coast and the correlation between UA and SST (sea surface temperature) from May to August in 1995 to 2016. The data used the 6 observations of the wind data of AWS/ASOS and the SST data of the COD/RISA provided by the National Institute and Fisheries Science near the East Sea coast. The UA was calculated quantitatively low but it rose when the actual cold water mass occurred. Correlation analysis between UA and SST showed the negative (-) r (correlation coefficient) predominately. At the time of cold-water mass in June to August 2013, the r had a very high negative value of -0.65 to -0.89 in the 6 observations. It proved that as the UA increases, the SST is lower. By knowing the UA, we were able to evaluate the trend of upwelling in the cold-water mass of the East Sea coast in the long term and it will contribute to minimizing the damage to aquatic organisms according to the size and intensity of the upwelling.

An Experimental Study for the Falling Test and Upwelling Effect of the Artificial Upwelling Structures in Flow Field (흐름장에서 인공용승구조물의 블록투하 및 용승효과에 관한 실험적 연구)

  • Jeon, Yong-Ho;Lee, Gyung-Sun;Kang, Yoon-Koo;Ryu, Cheong-Ro
    • Journal of Ocean Engineering and Technology
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    • v.21 no.4
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    • pp.21-27
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    • 2007
  • The multiplication equipment of marine products with artificial upwelling structures could be useful in the fishing grounds near coastal areas. Artificial upwelling structures could move the inorganic nutrients from the bottom to the surface. Artificial upwelling structures have been used to improve the productivity of fishing grounds. Until now, research on artificial upwelling structures has been related to the distribution of the upwelling region, upwelling structures, and the marine environment. However, little work on the optimum design of the rubber-mound artificial upwelling structures has been done to increase the efficiency of drawing up the inorganic nutrients. This study investigated the optimum cross-section of rubber-mound artificial upwelling structures by means of hydraulic experiments. The hydraulic experiments include the falling test of rubber. Based on the results of the falling test, the relationship between the length of the rubber mound and water velocity, and the relationship between the shape of the rubber and the stratification parameter were established. In addition, the effect of the void ratio of various artificial structures on the stratification parameter was studied. From the experiment, it was found that upwelling could be enhanced when the ratio of structure height to water depth was 0.3 and stratification parameter was 3.0. The upwelling was not improved when the void ratio exceeded 0.43. The optimum size of rubber mounds was determined when the incident velocity was influenced by the mean horizontal length rather than size of block.

A Study on the Flow Characteristics around Underwater Triangular Structure (삼각형상 수중구조물 주위의 유동특성에 관한 연구)

  • Han, Won-Hui;Cho, Dae-Hwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.1
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    • pp.21-27
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    • 2008
  • Triangular structure is used as basic shape of artificial structures for generating the upwelling current in order to make rich fishing ground at sea. Artificial upwelling current could bring the deep sea water containing a lot of nutrients from the bottom up to the surface. The purpose of this study is to examine the flow characteristics around underwater triangular structure with various stratification parameter. An experimental study was carried out for the triangular structure model in the circulating water channel to investigate flow characteristics by flow visualization method. A velocity fields around the underwater structure were measured by particle image velocimetry(PIV). The experimental results showed that the upwelling effect at the back and upper region of the structure could be best when the water depth was 2 times of the structure height and the stratification parameter was approximately 3.0. These quantitative data will be useful to determine the functional efficiency cf artificial upwelling structures.

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A Study on Characteristic of Three-Dimensional Flow around the Artificial Upwelling Structures (인공용승구조물 주변 흐름의 3차원 특성에 관한 연구)

  • Jeon, Yong-Ho;Ryu, Cheong-Ro
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2006.11a
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    • pp.290-293
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    • 2006
  • From the hydraulic experiment, it was concluded that upwelling could be enhanced when the relative structure height (the ratio of structure height to water depth) was 0.3 and stratification parameter was 3.0. In addition, the optimum size of rubbers was determined that the effect of the mean horizontal length of block was affected incident velocity than size of block. In the numerical experiment, the relation between the shape of rubber and stratification parameter was verified, ana the hydraulic characteristics of 3-D flow field around the artificial structures were investigated. Phenomena of flow field around the artificial upwelling structures corresponded with the results of hydraulic experiment. The position with maximum velocity in artificial upwelling structure was the center of top of its front side and the slip stream occurred at the inside and behind-bottom of artificial upwelling structures. The velocity of slip stream and early amplitude of velocity were higher in the inside than the behind-bottom.

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CHEMICAL OCEANOGRAPHIC ASPECT OF THE COLE WATER MASS IN OFFSHORE OF THE EAST COAST OF KOREA (한국 동해안 냉수괴의 해양화학적 고찰)

  • PARK Chung Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.11 no.2
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    • pp.49-54
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    • 1978
  • The cold water mass appeared in offshore of the east coast of Korea in summer season was studied in aspect of chemical oceanography. Such a typical relationship between phosphate and dissolved oxygen as shown in the upwelling regions could not be found in the east coast except around the Kampo coast, southern part of the east coast. It is possible to isolate the North Korean Cold Water from tile proper water of tile Japan Sea by using $\sigma_t-O_2$ diagram. The origin of the cold water mass in offshore of the east coast of Korea in summer is not mainly due to the development of upwelling of the proper water of the Japan Sea but thesouthwardflolvingoftheNorthKoreanCold Water.

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Bioecological Studies in the Upwelling Area of Cheju Island. ( I ) - Upwelling Phenomenon and Chemical Properties of Seawater in the Southwestern Coastal Area of Cheju Island (제주도 주변 용승역의 생물생태학적 기초연구 ( I )- 제주도 남서부 연안해역의 해수화학적 특성과 용승현상)

  • KANG Tae-Youn;CHOI Young-Chan;Go You-Bong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.5
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    • pp.603-613
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    • 1996
  • Hydrographic conditions (temperature, salinity, dissolved oxygen), nutrients, chlorophyll-a and suspended solid have been studied in the southwestern coastal area of Cheju Island from April 1993 to March 1994. Vertical profile of temperature, salinity and chemical properties (nutrients, chlorophyll-a) distribution in th southwestern sea of Cheju Island showed a upwelling feature. Although it was not clear in winter season, it seems to continued through out the year. In the surface water at the upwelling areas, the ranges of dissolved oxygen, nitrate, phosphate and silicate was $3.30\~8.43\;ml/l,\;0\~7.12{\mu}g/l,\;0.03\~1.75{\mu}g-at/l\;and\;2.75\~22.32\;{\mu}g-at/l$l, respectively. Nutrients was higher in the shore water than in the offshore water, because sufficient supply of nutrients from the bottom water by coastal upwelling. In November, especially high concentration silicate was observed at all the stations and depth in the study area. At all station of bottom water (down to the depth of 60 meter), concentration value of dissolved of gen was as high as 8 ml/l. Mean values of N/P was 8.0, lower than Redifield ratio of 16. The mean values of Si/P was observed to 46.3 in southwest of Cheju Island. Concentration of chlorophyll-a was in the range of $0.04\~2.36\;{\mu}g/l$. Concentration of chlorophyll-a in surface orator at all station was especially higher in spring than in other seasons. Mean concentration value of suspended solids was 3.14 mg/l $(0.75\~8.47\;mg/l)$. Ratio of the volatile suspended solids to the suspended solids was higher in the inshore water $(53\%)$ than in the offshore water $(46\%)$, and higher in the surface water than in the bottom water.

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Horizontal Behavior of Artificial Upwelling Device (인공용승장치의 수평거동특성)

  • Hong, Nam-Seeg;Kang, Seok-Wook
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2002.10a
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    • pp.240-244
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    • 2002
  • Mathematical and numerical modelling is proposed to evaluate the horizontal behavior of a wave-driven upwelling device and then, the horizontal behavior and the structural ability are inspected for the regular and irregular waves in East sea. Analysis results indicate that the buoy moves with the water particle and the pipe behaves cantilever beam. Also, it is found that the strength of pipe is sufficient to resist the internal moment

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한국 남동해역의 해류 모니터링

  • 이재철
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.3
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    • pp.211-212
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    • 2002
  • 해양과학공동연구소에서는 1999년부터 울산-감포 해역을 중심으로 하는 한국 남동해역 연안용승지역의 해양관측을 계속하면서 동시에 HF Radar를 이용하여 표층해류 모니터링 시스템을 구축하였다.