• Title/Summary/Keyword: Real sea environment

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Development of Real-time Oceanographic Information System for Pelagic Fishery Based on Argo Data (Argo 자료를 이용한 해외어장 실시간 해황정보시스템 개발연구)

  • Yang, Joon-Yong;Suk, Moon-Sik;Suh, Young-Sang;Jeong, Hee-Dong;Heo, Seung
    • Journal of Environmental Science International
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    • v.17 no.4
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    • pp.461-468
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    • 2008
  • Competitive power of pelagic fishery in Korea has been weakened by the domestic and international problems such as wage increase and exclusive economic zone. To make it worse, fishing fleet spends more than 80% of fishing time on searching fishing grounds. Real-time information on oceanographic data, temperature in particular, are likely to contribute to raise efficiency of fishing. However, available data obtained by satellite remote sensing, fixed buoy and drifting buoy, limited to sea surface or fixed positions. ARGO (Array for Real-time Geostrophic Oceanography), an international program, has delivered vertical profiles of temperature and salinity in the upper 2000m of the world ocean every 10 days using freely moving floats. We have developed real-time oceanographic information system for pelagic fishery based on the Argo data which has the contents of vertical profile, horizontal distribution and vertical section of temperature around fishing grounds and searched data can be download unrestrictedly. Comparison of skipjack catch with sea surface temperature and depth of $20^{\circ}C$ derived from Argo data in the West Equatorial Pacific revealed that Argo data are able to help fishing fleet to find fishing grounds and to increase catch.

A Study on Modification of Geographical Features Affecting Onset of Sea Breeze (지형적 특징이 해풍시작에 미치는 영향에 대한 연구)

  • 정우식;이화운
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.6
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    • pp.757-772
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    • 2003
  • We simulate the geographical effects on the onset time of sea breeze at Suyoung and Haeundae districts by using the LCM (Local Circulation Model). The following can be found out from the numerical simulation on Case I (real terrain) which considered the real geography of Busan metropolitan area. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. To find out more about the effects of terrain and geography on the onset time of sea breeze, the results of numerical simulation of virtual geography are as follows. In Case II (flat terrain), to find out how the terrain slope affects the onset of sea breeze, flat land and the ocean was considered. As a result, convergence of nighttime air mass at a Suyoung area and nighttime strong wind speed phenomenon was not shown. In Case III (modified flat terrain), to find out the effects of the irregularity of coastline affecting the onset of sea breeze, numerical simulation was carried out by simplifying the complex coastline into segments of straight coastline. So land breeze system and changing process of sea breeze after sunrise at Suyoung and Haeundae was simulated almost in a similar manner. Through this we could find the effects of coastal irregularities on onset of sea breeze.

A Study on the Panoramic Image Generation in the Sea Environment (해상 환경에서의 파노라믹 영상 생성 기법에 관한 연구)

  • 김효성;김길중
    • Journal of the Institute of Convergence Signal Processing
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    • v.3 no.3
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    • pp.41-46
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    • 2002
  • We generally used electric optical sensors in order to detect and identify sea objects efficiently. However due to the limitation of view-angle, the region acquired from the sense is restricted. So it is necessary to generate panoramic image from sea images acquired from pan-tilt camera. Previous mosaicing method is not able to generate panoramic image for sea environment because intensity is similar to all region and time varying. In this paper, we proposed new algorithm for generating high-resolution panoramic image on sea environment. Proposed algorithm use single-view point model, applying mosaicing result in feature environment to in sea environment, we overcame the limitation of previous method. In the result of virtual and real experiment, we showed that proposed algorithm is efficient for generating sea panoramic image.

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A Study on Measuring Procedure and Analysis Technique of Ship Infrared Signature at Sea (해상에서 적외선신호의 계측절차 및 분석기법 연구)

  • Cho, Yong-Jin
    • Journal of Ocean Engineering and Technology
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    • v.23 no.3
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    • pp.53-58
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    • 2009
  • A scale model test for ship Infra-Red signature measurements at sea is impossible, because it is sensitive to the environment. Since we can't control the meteorological environment of the real sea, it can't be carried out with the desired maritime environments. Therefore, in the sea, we made measurements of the weather, operating conditions of the ship, and ship IR signatures under given conditions, and then analyzed them. Conversely, we compared the results of the test with a prediction for a given scenario condition. This paper describes the test items, procedures, and measuring instruments of the experiments at sea and the results from basic researches for methods of estimation and analysis of the measured data.

Tracking Model of Drifted Ships for Search and Rescue (해상 수색구조를 위한 표류지점 신속추정모델 연구)

  • Lee Moonjin;Gong In-Young;Kang Chang-Gu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.2 no.2
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    • pp.78-85
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    • 1999
  • Tracking model of a drifted ship lot the search and rescue mission in southern sea of Korea is studied. In this model, search area is determined by considering standard deviation of position around reference point. The reference point is estimated for a given type of ship when marine environmental conditions such as wind and current are given. A database for environmental data, which is necessary for the real-lime tracking of drilled ship, is gel)elated on southern sea and western sea of Korea. Using this database, the real-time prediction of wind and current is possible. The simulated trajectories and search area of our model ate validated by comparing with reported real data.

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Application of Oil Spill Model to the South Sea of Korea (누유확산 모델의 남해안 적용)

  • Hong Keyyong;Lee Moonjin
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.1 no.1
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    • pp.56-65
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    • 1998
  • An oil spill model, Green Sea Ranger(GSR) based on trajectory and fate modeling of spilt oil behavior is introduced. The various physical models on weathering processes are reviewed and those adopted by GSR are described. A database for currents, which is necessary for the real-time simulation of oil spill, is generated on the south sea of Korea. The real-time prediction of tidal currents in the South Sea of Korea is carried out. Four major constituents (M₂, S₂, K₁, O₁ tide) are employed in the prediction, and those angular speeds and phases are determined from the astronomical arguments. The harmonic constants of the constituents are computed by solving shallow-water tide equations. The GSR has user-freiendly GUI and flexible framework which makes it easy to expand the database for sea environments in Korean coastal waters. The GSR is validated by the simulation of O-Sung oil spill caused by a grounded oil tanker in coastal sea near Maemol-do. The simulated trajectory is compared with observed one and it is shown that the GSR gives reasonable estimation on spilt oil bahavior.

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Performance analysis of real sea area according to OFDM parameters in the underwater channel environment of the West Sea and South Sea of Korea (대한민국 서해, 남해 수중 채널 환경에서 OFDM 파라미터에 따른 실해역 성능 분석)

  • Chung, Tea-Geon;Lim, Hyun-Taek;Im, Tae-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.8
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    • pp.1086-1094
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    • 2020
  • AThis paper measured real sea area for performance analysis according to distance from west sea and south sea of Korea. The performance of the underwater OFDM system was analyzed by comparing the performance of the West and South Seas by adjusting the number of data repetitive transmissions and the pilot symbol placement interval parameters based on the real-sea data measured from the distance and Data rate of the West and South Sea vessels. In conclusion, when comparing the performance of the South Sea at the Data rate and distance, the BER performance of the South Sea was similar at the 5 km South Sea and 1 km West Sea under the same conditions. Placement interval of pilot symbol at 10 km of South Sea and 3 km of West Sea is (𝚫f, 𝚫t) = (6, 3) and the number of times the PRB is (Rf, Rt) = (2, 1) repeated. We confirmed that we can send high data over long distances in the South Sea.

Regional sea water chlorophyll distribution derived from MODIS for near-real time monitoring

  • Liew, S.C.;Heng, A.W.C.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1039-1041
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    • 2003
  • Ocean color products derived from remote sensing satellite data are useful for monitoring the sea water quality such as the concentrations of chlorophyll, sediments and dissolved organic matter. Currently, ocean color products derived from MODIS data can be requested from NASA over the internet. However, due to the bandwidth limitation of most users in this region, and the time delay in data delivery, the products cannot be use for near-real time monitoring of sea water chlorophyll. CRISP operates a MODIS data receiving station for environmental monitoring purposes. MODIS data have been routinely received and processed to level 1B. We have adapted the higher level processing algorithms from the Institutional Algorithms provided by NASA to run in a standalone environment. The implemented algorithms include the MODIS ocean color algorithms. Seasonal chlorophyll concentration composite can be compiled for the region. By comparing the near-real time chlorophyll product with the seasonal composite, anomaly in chlorophyll concentration can be detected.

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Biochemical analysis of blood serum from wintering seabream with green liver syndrome (저수온기 돔류의 녹간증 혈청성분)

  • Choi, Hye-Sung;Park, Sung-Real;Jung, Choon-Goo
    • Journal of fish pathology
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    • v.15 no.1
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    • pp.43-48
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    • 2002
  • A blood biochemical analysis was carried out for the serum of wintering sea bream (red sea bream Pagrus major, black sea bream Acanthopagrus schlegeli, rock bream Oplegenathus fasciantuas) with green liver syndrome. GOT and GPT were significantaly elavated in the diseased sea bream. The value of $NH_{3}$ was slightly higher but those of TBIL. TP and UA were lower than the control. But there were no differences in albumin. Ca and glucose between the diseased and the control. These results suggent that a green liver syndrome in the sea bream might be related with nutritional defects and the stress of low water temperature during the winter.

Development of the Korea Ocean Prediction System

  • Suk, Moon-Sik;Chang, Kyung-Il;Nam, Soo-Yong;Park, Sung-Hyea
    • Ocean and Polar Research
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    • v.23 no.2
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    • pp.181-188
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    • 2001
  • We describe here the Korea ocean prediction system that closely resembles operational numerical weather prediction systems. This prediction system will be served for real-time forecasts. The core of the system is a three-dimensional primitive equation numerical circulation model, based on ${\sigma}$-coordinate. Remotely sensed multi-channel sea surface temperature (MCSST) is imposed at the surface. Residual subsurface temperature is assimilated through the relationship between vertical temperature structure function and residual of sea surface height (RSSH) using an optimal interpolation scheme. A unified grid system, named as [K-E-Y], that covers the entire seas around Korea is used. We present and compare hindcasting results during 1990-1999 from a model forced by MCSST without incorporating RSSH data assimilation and the one with both MCSST and RSSH assimilated. The data assimilation is applied only in the East Sea, hence the comparison focuses principally on the mesoscale features prevalent in the East Sea. It is shown that the model with the data assimilation exhibits considerable skill in simulating both the permanent and transient mesoscale features in the East Sea.

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