• Title/Summary/Keyword: sea state

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Abnormal Cooling before and after the 1982-1983 and 1997-1998 ENSO Events in the Korean East Sea Water (1982-1983년.1997-1998년 엘니뇨현상 전후 한국동해역에서의 이상 저수온 현상)

  • Hong, Chul-Hoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.4
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    • pp.294-300
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    • 2008
  • Abnormal cooling of the Korean East Sea Water(KESW) in the East Sea before and after the 1982-1983 and 1997-1998 ENSO events is examined using bimonthly routine observation data from the National Fisheries Research and Development Institute of Korea for the period 1965 to 2002. The KESW, which occupies roughly a region between the Korean Peninsula and west of approximately $131^{\circ}E$, showed extreme cold-state years(1981 and 1996) prior to the two strongest ENSO events of the last half-century. Inter-annual bimonthly mean anomalies at 100 m in the KESW region were $-3.10^{\circ}C\;and\;-3.41^{\circ}C(SD=1.4^{\circ}C)$ in 1981 and 1996, respectively. These results suggest that extreme cooling of the KESW may be a prelude to very strong ENSO events through large-scale teleconnections.

Image-Based Maritime Obstacle Detection Using Global Sparsity Potentials

  • Mou, Xiaozheng;Wang, Han
    • Journal of information and communication convergence engineering
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    • v.14 no.2
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    • pp.129-135
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    • 2016
  • In this paper, we present a novel algorithm for image-based maritime obstacle detection using global sparsity potentials (GSPs), in which "global" refers to the entire sea area. The horizon line is detected first to segment the sea area as the region of interest (ROI). Considering the geometric relationship between the camera and the sea surface, variable-size image windows are adopted to sample patches in the ROI. Then, each patch is represented by its texture feature, and its average distance to all the other patches is taken as the value of its GSP. Thereafter, patches with a smaller GSP are clustered as the sea surface, and patches with a higher GSP are taken as the obstacle candidates. Finally, the candidates far from the mean feature of the sea surface are selected and aggregated as the obstacles. Experimental results verify that the proposed approach is highly accurate as compared to other methods, such as the traditional feature space reclustering method and a state-of-the-art saliency detection method.

CLIMATIC TRENDS OF SOME PARAMETERS OF THE SOUTHERN OCEAN DERIVED FROM REMOTE SENSING DATA

  • Lebedev, S.A.
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.1023-1026
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    • 2006
  • As it was shown recently, climate changes in Antarctica resulted in interannual trends of some climatic parameters like sea level pressure, surface air temperature, ice thickness and others. These tendencies have effect on the Southern Ocean meteorological and hydrological regime. The following remote sensing data: AVHRR MCSST data, satellite altimetry data (merged data of mission ERS-2, TOPEX/Poseidon, Jason-1, ENVISAT, GFO-1) are used to analyse the interannual and/or climatic tendency of sea surface temperature (SST) and sea level anomaly (SLA). According to the obtained results, SST has negative trend $-0.02{\pm}0.003^{\circ}C/yr$ for 24-yr record (1982-2005) and SLA has positive trend $0.01{\pm}0.005$ cm/yr for 24-yr record (1982-2005) and $0.24{\pm}0.026$ cm/yr for 12-yr record (1993-2005). However in some areas (for example, Pacific-Antarctic Ridge) SST and SLA tendencies are stronger $-0.065{\pm}0.007^{\circ}C/yr$ and $-0.21{\pm}0.05$ cm/yr, respectively.

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A Study on the Implication of Sustainability and Environmental Assessment (지속가능성과 환경평가의 연계에 관한 연구)

  • Hong, Sang-Pyo
    • Journal of Environmental Impact Assessment
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    • v.20 no.3
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    • pp.269-279
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    • 2011
  • Sustainability assessments tend to integrate ecological, social, and economic concerns. Sustainability assessment could be considered the highest rung in the assessment ladder. Broad strategies that seek to integrate individual SEA(Strategic Environmental Assessment) could be subjected to a sustainability assessment. Sustainability assessment could incorporate global and transboundary effects and priorities into SEA and project-level EIA(Environmental Impact Assessment). SEA could provide an environmental context and direction for project-level EIA. Procedural and substantive EIA requirements can be addressed through tiering such as sustainability assessment, SEA, project-level EIA. In Korea, PERS(Prior Environmental Review System) that has been utilized to evaluate administrative plans related with various kinds of development projects should be evolved not only to incorporate environmental impacts into early stage decision-making, but also to implicate sustainability assessments that include social equity and economic efficiency. Integration of SEA and sustainability assessment can be initiated through the application of DPSIR (Driving Force - Pressure - State - Impact - Response ) framework that was developed by European Environmental Agency.

Roles and strategic functions of the Jeju Naval Base (제주 해군기지의 역할과 전망)

  • Lee, Choon Kun
    • Strategy21
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    • s.39
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    • pp.140-162
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    • 2016
  • The construction of Jeju Naval Base was finally completed and donated to the Republic of Korea Navy on February 26th this year. There is no doubt that the new base will contribute to the substantial augmentation of Korea's naval power and maritime security. However, we should note that the new naval base took a long and hard twenty-three years to be completed. In the 21st century, Korea should adopt a new strategy that can fulfill the security requirements of Korea for the new age of international relations. The 21st century is characterized by globalization, and in the world of globalization, a national boarder has become meaningless. In the late 20th century, after the Cold War, trade between countries have greatly increased and so did the importance of the seas. Having transformed from an agricultural country into a commercial country, Korea went from a continental state to a maritime state. Korea has become the 9th largest trading state, and obviously, the importance of the sea has become significant. Korea's national strategic focus needs to be on the sea for national survival. Thus, since the 1990s, the Korean Navy has planned to build the Jeju Naval Base. Jeju, due to its geopolitical characteristics, is extremely important to the 21st century Korea's economy and national security. Jeju is the starting point of the sea route that reaches out to the world, and at the same time, the ending point of the sea route that heads towards Korea. Jeju is located in the center of Northeast Asia and thus, Jeju Naval Base is extremely important for the area's security and order. Jeju Naval Base will be very useful not only for the maritime security of Korea, but also for keeping peace and order in Northeast Asia. Jeju Naval Base was the minimal effort against the six sea route security threats towards Korea. The six sea route threats are: 1) Threat from North Korea; 2) China's Threat towards Korea's sovereignty; 3) China's treat towards Korea's fishery; 4) Threat from Japan; 5) Threat towards Korea's sea routes; 6) Threat from recent phenomena of isolationism of the United States. Jeju Naval Base is built for both warships and civilian ships--such as cruise ships--to use. Just like the United States' Pearl Harbor, Jeju Naval Base will become not only the largest military base, but a beautiful tourist site.

Characteristics on the response of the stern trawler according to the state of its operation (선미트롤어선의 운항 형태에 따른 거동 특성)

  • PARK, Chi-Wan;KIM, Jong-Wha;KIM, Hyong-Seok;KANG, Il-Kwon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.52 no.4
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    • pp.339-346
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    • 2016
  • The aim of this research was to the experimental data using statistical and spectral analyzing method to get the motion reponses of a stern trawler in operation states such as drifting, sailing and trawling according to the wave height. In drifting, the significant and the maximum valuer of roll in beam sea increased according to the wave height, but those of pitch decreased. The response and the period of peak of roll in beam sea were increased, but those of pitch decreased. In navigation, the significant and maximum values of roll increased remarkably according to the wave height, but those of pitch changed a little. The response of roll was highest in quartering sea, beam sea and then following sea, but those of pitch was highest in bow sea, head sea and then beam sea in the order of all wave heights. The period of peak of roll due to the wave height and the wave direction changed from 3.8 to 9.9 seconds, and those of pitch changed from 3.3 to 10.4 seconds. In trawling, the significant and maximum values of roll increased a little according to the wave height, but those of pitch increased significantly. The response of roll was highest in beam sea, bow sea and then quartering sea, but those of pitch was highest in head sea, following sea, and then beam sea in the order. The period of peak of roll due to the wave height and the direction changed from 6.6 to 10.9 seconds, and those of pitch changed from 6.7 to 11.2 seconds.

Novel Alkali-Stable, Cellulase-Free Xylanase from Deep-Sea Kocuria sp. Mn22

  • Li, Chanjuan;Hong, Yuzhi;Shao, Zongze;Lin, Ling;Huang, Xiaoluo;Liu, Pengfu;Wu, Gaobing;Meng, Xin;Liu, Ziduo
    • Journal of Microbiology and Biotechnology
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    • v.19 no.9
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    • pp.873-880
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    • 2009
  • A novel xylanase gene, Kxyn, was cloned from Kocuria sp. Mn22, a bacteria isolated from the deep sea of the east Pacific. Kxyn consists of 1,170 bp and encodes a protein of 390 amino acids that shows the highest identity (63%) with a xylanase from Thermohifida fusca YX. The mature protein with a molecular mass of approximately 40 kDa was expressed in Escherichia coli BL21 (DE3). The recombinant Kxyn displayed its maximum activity at $55^{\circ}C$ and at pH 8.5. The $K_m,\;V_{max}$, and $k_{cat}$ values of Kxyn for birchwood xylan were 5.4 mg/ml, $272{\mu}mol/min{\cdot}mg$, and 185.1/s, respectively. Kxyn hydrolyzed birchwood xylan to produce xylobiose and xylotriose as the predominant products. The activity of Kxyn was not affected by $Ca^{2+},\;Mg^{2+},\;Na^+,\;K^+$, ${\beta}$-mercaptoethanol, DTT, or SDS, but was strongly inhibited by $Hg^{2+},\;Cu^{2+},Zn^{2+}$, and $Pb^{2+}$. It was stable over a wide pH range, retaining more than 80% activity after overnight incubation at pH 7.5-12. Kxyn is a cellulase-free xylanase. Therefore, these properties make it a candidate for various industrial applications.

THE TATAR STRAIT SEA LEVEL SESONAL VARITIONS BY SAT-ELLITE ALTIMETRY DATA

  • Sedaeva, Olga;Romanov, Alexander;Vilyanskaya, Elena;Shevchenko, Georgy
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.844-847
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    • 2006
  • In this work Topex/Poseidon altimeter data 1993 - 2002 were used. There are three altimetry tracks (one ascending and two descending) that cross Tatar Strait. The data were collected in the points of sub-satellite tracks with the step 0.25 degree. 10-years average values were calculated for each month. The seasonal sea level variations were compared with tide gauges data. The well expressed annual cycle (with maximum at July-August and the minimum at February-March) prevails in the Tartar Strait. However, the seasonal variations expressed much weakly in both the altimetry track points and Kholmsk - Nevelsk tide-gauges that locate close to La Perouse Strait because of Okhotsk Sea influence. The sea level slopes between the Sakhalin Island and the continent coasts were analyzed in different seasons. We found that sea level increases near Sakhalin coast in spring and summer that corresponds to the northward flow. In autumn, otherwise, the sea level decreases near Sakhalin Island that corresponds to southward current. This result is verified by the CTD data gathered on the standard sections. Well-expressed upwelling is observed near coastline of Sakhalin Island in fall season. This phenomenon is caused by the northerly and the northwesterly wind which are typical for cold season.

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