• Title/Summary/Keyword: OPR

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Development of a Fixing Apparatus Available to Mount-and-detach ADCP on a Small Vessel (소형선박용 착.탈식 ADCP 고정장치 개발)

  • Hwang, Sang-Chul;Jeon, Dong-Chull;Kang, Jae-Hoon;Kim, Cheol-Soo
    • Ocean and Polar Research
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    • v.26 no.3
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    • pp.481-486
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    • 2004
  • A portable apparatus mounting Acoustic Doppler Current Profilers (ADCP) to any small boat was developed to effectively measure currents in shallow and narrow coastal seas like the west coasts of Korea. Characteristics of the apparatus is that an underwater fish-shaped body protecting an ADCP is designed to reduce the drag during the cruise, which can be freely mounted and detached from a boat with a clamp. Several cruise outputs prove themselves that the apparatus is properly designed for the intended purpose, to minimize air bubbles and to control the submerged depth of the sensor.

Test of Fishing Activity Levels using Schaefer Model (쉐퍼모형 응용을 통한 어로활동수준 검정)

  • Lee, Kwang-Nam
    • Ocean and Polar Research
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    • v.31 no.2
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    • pp.157-165
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    • 2009
  • The study examined overuse of the fishery resource. Influence of fishing activity was estimated by application of Schaefer model's. Fishing efforts that produced the maximum sustainable yield were determined in the model, allowing the effect of overfishing to be assessed. In the model, a wide variety of fish species as well as crustaceans and shellfish were susceptible to overfishing, while mollusks were not. Overfishing by modern techniques exacted a greater toll than more traditional methods. The results of the modeling study suggest that the 'Buy bag' input-control system of fisheries resource management warrants consideration, as does modernization, expansion and strengthening of self-control management of the fishery resource. Finally, more effective efforts in dissemination of policy information and education concerning the fishery resource are needed.

Ocean Policy of Japan: Focusing on the Relations with Pacific Island Nations (일본의 해양 정책 - 태평양 도서국과의 관계를 중심으로)

  • Hyun, Daesong
    • Ocean and Polar Research
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    • v.35 no.4
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    • pp.355-371
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    • 2013
  • The purpose of this study is to explore the history of the relationships between Japan and the Pacific Island Nations in the context of its ocean policy, and to survey the current situation. Particularly, this paper inquires into how Japan's maritime policy, nuclear policy, and official development assistance policy have affected relationships with countries in this region. Firstly, this paper gives a brief overview of the socio-political situations of Pacific Island Nations. Secondly, the history of the 'Southward Advance Theory' adopted as national policy by Japan in the Meiji era is summarized. Thirdly, how Japan successfully re-entered this region despite conflicts surrounding the nuclear issue after the Second World War is explored. Lastly, this paper investigates how official development assistance and PALM (Pacific Island Leaders Meeting) helped to develop relations between Japan and the Pacific Island Nations.

Simulation of the Mixed Layer in the Western Equatorial Pacific Warm Pool

  • Jang, Chan-Joo;Noh, Yign
    • Ocean and Polar Research
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    • v.24 no.2
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    • pp.135-146
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    • 2002
  • The upper ocean in the western equatorial Pacific warm pool during TOGA-COARE IMET IOP was simulated using a one-dimensional turbulence closure ocean mixed-layer model, which considered recent observations, such as the remarkable enhancement of turbulent kinetic energy near the ocean surface. The shoaling/deepening of the mixed layer and warming/cooling subsurface water in the model were in reasonable agreement with the observations. There was a significant improvement in simulating the cooling trend of the sea surface temperature under a westerly wind burst with heavy rainfall over previous simulations using bulk mixed-layer models. By contrast the simulated sea surface salinity (SSS) departed significantly from the observed SSS, especially during a westerly burst and the subsequent restratification period, which might be due to 3-D control processes, such as downwelling/upwelling or advection.

Volume Transport through the La-Perouse (Soya) Strait between the East Sea (Sea of Japan) and the Sea of Okhotsk

  • Saveliev Aleksandr Vladimirovich;Danchenkov Mikhail Alekseevich;Hong Gi-Hoon
    • Ocean and Polar Research
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    • v.24 no.2
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    • pp.147-152
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    • 2002
  • Seasonal and interannual variation of volume transport through the La-Perouse Strait were estimated using the difference of sea level observed at Krillion of Sakhalin, Russia, and Wakkanai of Hokkaido, Japan, during the period of 1975-1988. Historical sea level measurements between Russian and Japanese tide gauge data were normalized using an independent direct volume transport measurement. Volume transport from the East Sea (Sea of Japan) to the Sea of Okhotsk varied from -0.01 to 1.18 Sv with an annual mean value of 0.61 Sv. Monthly water transport rates showed a unimodal distribution with its maximum occurring in summer (August) and minimum in winter (December-February). The annual mean volume transport varied from 0.2 to 0.8 Sv during the period of 1975-1988 with the maximum variance of 0.6 Sv.

A Bioeconomic Analysis of the Management Policies for the United States Gulf of Mexico Red Grouper Fishery

  • Kim, Do-Hoon
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.483-491
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    • 2003
  • Since the red grouper was declared overfished, the Gulf of Mexico Fishery Management Council must prepare a rebuilding plan considering the following alternative management policies: a Total Allowable Catch (TAC), 5-month season closure, 1800-pound trip limit, and a 50-fathom longline boundary. This study was aimed at evaluating the effects of proposed policies for rebuilding the red grouper stock in a 10-year period by developing a bioeconomic model. Under the assumption that the recreation sector was held to its share of TAC (24% of the total quota), the target stock biomass goal was attained in all policies. The NPV was the largest in the 5-month season closure policy if the output price did not fall. There were distributional effects on the different components of the fleets in the 1800-pound trip limit and the 50-fathom longline boundary policy.

Macroalgal Flora of Kongsfjorden in Svalbard Islands, the Arctic (북극 스발바드 군도 Kongsfjorden의 해조상)

  • Kim, Ji-Hee;Chung, Ho-Sung;Choi, Han-Gu;Kim, Yea-Dong
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.569-591
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    • 2003
  • Marine benthic flora was investigated in an Arctic bay. Specimens of chlorophyte, phaeophyte, and rhodophyte were collected and examined over the period from July to August 2003 from Kongsfjorden Spitsbergen in Svalbard Islands. A total of 28 genera and 32 species (5 chlorophytes, 18 phaeophytes, and 9 rhodophytes) was identified and described. A green alga Enteromorpha linza(Linnaeus) J. Agardh, a brown alga Asperococcus compresus Griffiths ex Hooker, and three red algae Gracilaria gracilis (Stackhouse) Steentoft et al., Rhodymenia pacifica Kylin and Schizochlaenion rhodotrichum Wynne et Norris were recorded in Svalbard Islands for the first time.

The Oxygen-Transport System of Polar Fish: The Evolution of Hemoglobin

  • Verde Cinzia;Prisco Guido di
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.617-623
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    • 2003
  • Organisms living in the Arctic and Antarctic regions are exposed to strong constraints, of which temperature is a driving factor. Evolution has led to special adaptations, some with important implications at the biochemical, physiological, and molecular levels. The northern and southern polar oceans have very different characteristics. Tectonic and oceanographic events have played a key role in delimiting the two polar ecosystems and influencing evolution. Antarctica has been isolated and cold longer than the Arctic; its ice sheet developed at least 10 million years earlier. As an intermediate system, the Arctic is a connection between the more extreme, simpler Antarctic system and the very complex temperate and tropical systems. By studying the molecular bases of cold adaptation in polar fish, and taking advantage of the information available on hemoglobin structure and function, we analysed the evolutionary history of the ${\alpha}\;and\;{\beta}globins$ of Antarctic and Arctic hemoglobin using the molecular clock hypothesis as a basis for reconstructing the phylogenetic relationships among species.

Krill and Currents-Physical and Biological Interactions Influencing the Distribution of Euphausia superba

  • Nicol, Stephen
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.633-644
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    • 2003
  • The distribution and abundance of Antarctic krill (Euphausia superba), particularly in the South Atlantic, has traditionally been viewed as primarily determined by the flow of the Antarctic Circumpolar Current. Krill are viewed as being particles on a conveyor belt that carries them around the Antarctic continent resulting in a single circumpolar population. The evidence to support this viewpoint is largely circumstantial and there is very little direct evidence available of krill being moved by the currents-krill flux. There is also considerable biological and physical evidence which suggests that other factors may play a dominant role in the life history and distribution of krill. This review examines the evidence fur krill flux and also examines evidence that does not accord with this theory. The management implications of assuming krill flux are outlined and some lines for future research are suggested.

Heavy Metal Pollution Monitoring at King Sejong Station, King George Island, Antarctica

  • Ahn, In-Young;Choi, Hee-Seon;Kim, Ko-Woon
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.645-652
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    • 2003
  • The coastal environment of King George Island is potentially subject to contamination by pollutants arising from station operations, such as emissions from fossil fuel burning, oil spills, waste disposal, etc. As a preparatory step to assess such impacts on the marine environment and living organisms of this island, two molluscan species (the bivalve Laternula elliptica and the gastropod Nacella concinna) were selected as biomonitors for metal pollution monitoring, and their baseline levels have been investigated for the past several years at King Sejong Station. In this review, variability of the baseline levels is discussed in relation to body size, tissue type, and sex. Natural elevations of some metals are also discussed with respect to the environmental characteristics of this region.