• Title/Summary/Keyword: Oceanic condition

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Accuracy Assessment of Sea Surface Temperature from NOAA/AVHRR Data in the Seas around Korea and Error Characteristics

  • Park, Kyung-Ae;Lee, Eun-Young;Chung, Sung-Rae;Sohn, Eun-Ha
    • Korean Journal of Remote Sensing
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    • v.27 no.6
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    • pp.663-675
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    • 2011
  • Sea Surface Temperatures (SSTs) using the equations of NOAA (National Oceanic and Atmospheric Administration) / NESDIS (National Environmental Satellite, Data, and Information Service) were validated over the seas around Korea with satellite-tracked drifter data. A total 1,070 of matchups between satellite data and drifter data were acquired for the period of 2009. The mean rms errors of Multi- Channel SSTs (MCSSTs) and Non-Linear SSTs (NLSSTs) were evaluated to, in most of the cases, less than $1^{\circ}C$. However, the errors revealed dependencies on atmospheric and oceanic conditions. For the most part, SSTs were underestimated in winter and spring, whereas overestimated in summer. In addition to the seasonal characteristics, the errors also presented the effect of atmospheric moist that satellite SSTs were estimated considerably low ($-1.8^{\circ}C$) under extremely dry condition ($T_{11{\mu}m}-T_{12{\mu}m}$ < $0.3^{\circ}C$), whereas the tendency was reversed under moist condition. Wind forcings induced that SSTs tended to be higher for daytime data than in-situ measurements but lower for nighttime data, particularly in the range of low wind speeds. These characteristics imply that the validation of satellite SSTs should be continuously conducted for diverse regional applications.

On the Characteristics of the Oceanic Condition in the Surface Layer of the Northwestern East Sea (Japan Sea) (동해 북서해역의 표층해황 특성)

  • 김철호
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.8 no.2
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    • pp.215-220
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    • 1996
  • Seasonal and interannual variations of the oceanic condition in the surface layer of the northwestern East Sea are described. The seasonal variation shows two types in the water circulation. In the first type the East Korean Warm Current (EUC) Water are dominant in the East Korean Bay in spring, while in summer the cold water region develops as the North Korean Cold Current (NKCC) becomes strong. In the second type the cold water appears in the East Korean Bay from spring, but in summer the EKWC comes close to the coast, thus influencing the coastal cold water region. The characteristics of the interannual variation can be classified into 4 types according to the relative strength between the EKWC and the NKCC, and the paths of these currents. In each case various sizes of cyclonic cold eddies and/or anti-cyclonic warm eddies are formed frequently in the East Korean Bay.

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A Diagnosis of Strategy Execution Ability and Corresponding Measures for Korean Oceanic Shipping Companies

  • Ahn, Ki-Myung;Kim, Myung-Jae
    • Journal of Navigation and Port Research
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    • v.34 no.7
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    • pp.595-601
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    • 2010
  • This paper aims to diagnose the strategy execution ability and to provide corresponding measures for Korean oceanic shipping companies. The analysis method is the t-test between importance awareness and Corresponding ability for strategy execution diagnosis index(XPP). According to the diagnosed results, the strategy development is unsatisfactory because the strategy implemented does not adhere to concurrent environmental change. Moreover, the execution of the strategy is also unsatisfactory. Therefore, an evaluation shows that there is a need for a SWOT analysis using BSC, an organization structure to strengthen the strategy execution ability and the support from the market condition analysis prediction center.

Development of Oceanic General Circulation Model for Climate Change Prediction (기후변화예측을 위한 해양대순환모형의 개발)

  • Ahn, Joong-Bae;Lee, Hyo-Shin
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.1
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    • pp.16-24
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    • 1998
  • In this study, Ocean General Circulation Model (OGCM) has been developed as a counterpart of Atmospheric General Circulation (AGCM) for the study of coupled ocean-atmosphere climate system. The oceanic responses to given atmospheric boundary conditions have been investigated using the OGCM. In an integration carried out over 100 simulated years with climatological monthly mean data (EXP 1), most parts of the model reached a quasi-equilibrium climate reproducing many of the observed large-scale oceanic features remarkably well. Some observed narrow currents, however, such as North Equatorial Counter Current, were inevitably distorted due to the model's relatively coarse resolution. The seasonal changes in sea ice cover over the southern oceans around Antarctica were also simulated. In an experiment (EXP 2) under boundary condition of 10-year monthly data (1982-1991) from NCEP/NCAR Reanalysis Project model properly reproduced major oceanic changes during the period, including El Ni$\tilde{n}$os of 1982-1983 and 1986-87. During the ENSO periods, the experiment showed eastward expansion of warm surface waters and a negative vertical velocity anomalies along' the equator in response to expansion of westerly current velocity anomalies as westerly wind anomalies propagated eastward. Simulated anomalous distribution and the time behavior in response to El Ni$\tilde{n}$o events is consistent with that of the observations. These experiments showed that the model has an ability to reproduce major mean and anomalous oceanic features and can be effectively used for the study of ocean-atmosphere coupling system.

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Sea Wave Modeling Analysis and Simulation for Shipboard Landing of Tilt Rotor Unmanned Aerial Vehicle (틸트로터 무인기 함상이착륙 위한 파고운동 해석 및 시뮬레이션)

  • Yoo, Chang-Sun;Cho, Am;Park, Bum-Jin;Kang, Young-Shin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.9
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    • pp.731-738
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    • 2014
  • The mission of UAV has been expanded from a land to an ocean based on an enhancement of its technologies. Korea Aerospace Research Institute (KARI) also tries to expand the mission of tilt rotor UAV to an ocean, in which the shipboard landing of UAV is required. However the environment of an oceanic operation is severer than that of land due to salty, fogy, and windy condition. The landing point for automatic landing is not fixed due to movement of shipboard in roll, pitch, and heave. It makes the oceanic operation and landing of UAV difficult. In order to conduct an oceanic operation of tilt rotor UAV, this paper presents that the sea wave modeling according to the sea state is conducted and the shipboard landing of tilt rotor UAV under the sea wave is tested and evaluated through the flight simulator for UAV.

The oceanic condition of the Tsushima Warm Current region the southern part of the East Sea (Sea of Japan) In June, 1996

  • Lee Chung Il;Cho Kyu Dae
    • Proceedings of KOSOMES biannual meeting
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    • 2003.11a
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    • pp.167-174
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    • 2003
  • Oceanic conditions of the Tsushirm Wann Current (1WC) region in the southern area if the East Sea (the Japan Sea) are examined using data obtained from a CREAMS (Circulation Research if the East Asian Marginal Seas) cruise in June 1996. In 1990s, a lower temperature appears in $19\%$ and in this period, two branch of the TWC exist and the first branch of the TWC flows inshore if the Japanese coastal region compared to tfr1t in the other years, especially in the sfr1llower water layer at less th:1n about 2mm. The TWC cored with the higher salinity (>34.6 psu) is clearly observed over the continental shelf zone in the Japanese coastal region and offshore and identified by geostrophic calculation Intrusion if the TWC into the East Sea through the Korea Strait (the Tsushima Strait) makes the density structure in the water column change and the water mass in the TWC region is unstable based on Brunt- Vaisala frequency.

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Numerical Modelling Of The Coastal Upwelling Near The Poleward Edge Of The Western Boundary Current

  • An, Hui Soo
    • 한국해양학회지
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    • v.16 no.1
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    • pp.12-23
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    • 1981
  • A numerical experiment is made in order to clarify the mechanism of the upwelling phenomenon along the coast near the poleward edge of the western boundary current. The possibility of the upwelling is suggested from the analysis of the observational data in the east of Honshu, Japan, and in the south eastern coast of Korean Peninsula. This upwelling phenomenon is very deep and can be traced to the bottom layer. The upwelling phenomenon seems to be a general oceanic feature which characterizes the region along the west coast near the poleward edge of the western boundary current. This experiment is simulating the oceanic condition of the transition region between Kuroshio front and the Oyashio front in the east of Honshu, Japan. The possible explanations of the causes of the upwelling are as follows;In the interior of the modeled ocean the cold heavy water supplied from the north and the warm light water from the south make the north-south gradient of the pressure field and accelerate the eastward current to produce the h-orizontal divergence feld near the west coast. The divergence is compensated by the upwelling near the separation region. Another one is that the upwell-ed cold water strengthen constantly the pressure gradient which is balanced by the northward current and is weakened by the horizontal diffusion.

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Case Study on Habitability of Superstructure built on Floating Structure

  • Maruyoshi Koichi;Cho Yong-Soo;Song Hwa-Cheol;Saijo Osamu
    • Journal of Navigation and Port Research
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    • v.30 no.2
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    • pp.131-136
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    • 2006
  • Researches on a superstructure built on a floating structure in the shape of pontoon type have begun in recent years. A superstructure responds by wave load and it is important to evaluate its habitability. The purpose of this study is evaluation and investigation of habitability of a superstructure due to wave for 10 year return period. In this study, response analyses of the superstructure built on middle-sized floating structure due to the waves of three cases were carried out by 3-D integration analysis, which means analyzing the calculation model integrated a superstructure with a floating structure, and its habitability was evaluated by the evaluation diagrams. As the result, the habitability differed by each wave condition The use of a superstructure is restricted according to the disposition of a floating structure for incident wave angle.

A Study of Strategy Development of Marina using ubiquitous sensor network (유비쿼터스 센서네트워크 기반의 스마트 마리나 구축에 관한 연구)

  • Kang, Nam-Seon;Kwon, Youn-Won
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2011.06a
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    • pp.96-97
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    • 2011
  • In these days many korean people have much interested in oceanic sports and oceanic leisure equipment.. However, the current condition for the marine leisure in korea are not advanced even worse than wnderdeveloped countries.. Recently several suggestion for vitalization on the marine leisure industry and preparations of the laws & the regulations for marine leisure.. This paper suggest the new marina model using ubiquitous sensor network to reduce the risk of the policy and the investment in the filed og marine leisure industry.

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