• 한국음향학회지
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• 제19권2호
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• pp.46-53
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• 2000

내만은 잦은 선박통행, 인공구조물에 의한 쇄파 그리고 생물학적 활동으로 외해에 비해 공기방울의 생성이 활발하다. 따라서 공기방울의 생성과정과 분포형태가 주로 쇄파에 의존하는 외해의 특성과는 매우 다른 내만에서의 해수면 후방산란신호를 분석하였다. 해수면 후방산란신호의 입사각에 따른 변화, 해수면 부근에서의 잔향특성 그리고 산란신호의 주파수 확장폭 등을 외해의 산란신호 특성과 비교하였다. 내만에서의 표층 산란신호는 시간영역에서는 매우 불규칙한 진폭의 변화를 보이고 주파수 확장폭이 외해의 거친 해수면보다 더 크게 나타나고 있다. 소위 해수면 잔향신호의 진폭 분포는 기존에 알려진 Rayleigh 분포를 따르지 않고 있어 공기방울의 크기 및 수직분포가 외해와 비교, 매우 상이한 특성을 갖고 있음을 보여주고 있다.

• 한국해양학회지
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• 제20권3호
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• pp.37-54
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• 1985

1984년 5월과 10월, 2회에 걸쳐 동해 서남 해역에서 조사한 수온, 클로로필-a, 영양염, 식물플랑크톤 및 일차생산에 관한 자료를 토대로 하여 대산 수역의 phytohydrography를 논의하였다. 식물플랑크톤의 종별 양적분포로 부터 특성 해수의 이전 환경을 추측할 수 있었는데, 이는 해양물리${\cdot}$화학적인 자료만으로는 기대하기 어려운 결과였다. 울기 및 감포 부근 해역의 상층부에서는, 그 하층에 근접한 냉수로 부터 영양염을 공급받아, 높은 일차생산력, 높은 클로로필-a 및 낮은 미세플랑크톤 비율 등의 특징이 나타났다. 반면에 대마난류수에는 매우 낮은 일차생산력, 빈약한 현존량 및 극히 높은 미세플랑크톤 비율 등의 특징이 나타나 좋은 대조를 이루었다. 연구해역에서 식물플랑크톤의 세포수 뿐만 아니라 클로로필-a 및 일차생산량에서도 미세플랑크톤이 압도적으로 우세함을 확인하였다. 이는 한반도 전해역 가운데 난류수가 예외적으로 강하게 유입되는 연구해역의 생물해양학적 특성을 잘 반영해 주는 현상이다.

• 해양환경안전학회지
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• 제5권2호
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• pp.57-65
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• 1999

The in situ observations and the seawater analyses were conducted at all seasons from July 1996 to April 1999 for the purpose of describing the characteristics of seasonal variations of water quality in Mokpo harbour, Korea. Vertical stratification started to be formed in water column in spring, developed in summer and disappeared in fall. In summer, vertical density distribution of water column was found to be in stable structure with lower temperature and higher salinity of bottom water, and the vertical mixing of water between surface and bottom layers was restricted. In winter, however, surface water was found to be similar to bottom water in temperature and salinity, and water column was in unstable structure and in well-mixed condition between surface and bottom waters. The saturation percentage of dissolved oxygen(DO) in bottom water of inner part of Mokpo harbour at all seasons was shown to be decreased to the third grade or under the third grade of Korean standards of seawater quality. In particular, dissolved oxygen was oversaturated in surface water and undersaturated in bottom water in summer, due to stratification and organic pollution. The difference of DO concentration between surface and bottom waters was found to be greater in spring and summer than in fall and winter, due to stratification and photosynthesis of phytoplankton. The concentrations of chemical oxygen demand(COD) over the entire waters of Mokpo harbour were found to fluctuate from below the third grade to the first grade of Korean standards through all seasons and COD concentrations of same seasons were shown to be different year after year. In particular, in view of COD, the annual average seawater quality of Mokpo harbour was evaluated to be in third grade of Korean standards, due to organic pollution. The average COD of surface water was greater than that of bottom water in spring and summer, due to the autochthonous COD caused by production of phytoplankton in surface waters, while the average COD of surface water was similar to that of bottom water in fall and winter, due to the vertical mixing of water between surface and bottom layers.

• 한국수산과학회지
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• 제46권2호
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• pp.186-194
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• 2013

We compiled and analyzed long-term time-series data collected in Korea to evaluate changes in oceanographic conditions and marine ecosystems near Jeju Island ($33^{\circ}00^{\prime}-34^{\circ}00^{\prime}\;N$, $125^{\circ}30^{\prime}-127^{\circ}30^{\prime}\;E$) from 1981 to 2010. Environmental data included depth-specific time series of temperature and salinity that have been measured bimonthly since 1961 in water columns at 175 fixed stations along 22 oceanographic lines in Korean waters by the National Fisheries Research & Development Institute, and time series of estimated volume transport of the Tsushima Warm Current (TWC) and Korea Strait Bottom Cold Water (KSBCW) for the period from 1961 to 2008. We analyzed the species composition in terms of biomass of fish species caught by Korean fishing vessels in the waters near Jeju Island (1981-2010). Data were summarized and related to environmental changes using canonical correspondence analysis (CCA). The CCA detected major shifts in fish community structure between 1982 and 1983 and between 1990 and 1992; the dominant species were a filefish during 1981-1992 and chub mackerel from 1992 to 2007. CCA suggested that water temperature and salinity in the mixed layer and the volume transport of the TWC and the KSBCW were significantly related to the long-term changes in the fish community in the waters off Jeju Island. Fish community shifts seemed to be related to the well-established 1989 regime shift in the North Pacific. Further studies are required to elucidate the mechanisms driving climate change effects on the thermal windows and habitat ranges of commercial species to develop fisheries management plans based on reliable projections of long-term changes in the oceanographic conditions in waters off Jeju Island.

• 수산해양교육연구
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• 제18권2호
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• pp.85-97
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• 2006

With extension of national jurisdiction over coastal living resources, new dimensions and objectives should be added to international cooperation in distant-water fisheries concepts. For distant-water fishing nations, Korea, joint exploitation of these resources is today considered not only as a way of producing additional income opportunities, but first of all as at least a partial solution to neutralization of harvesting limitations imposed on them in traditionally exploited fishing grounds.This paper explores the development of Korean distant-water fisheries agreements and reviews the various types of agreements currently in place and discusses the future of Korean distant-water fisheries agreements with third countries. The relationship between coastal States and fishing fleets from non-adjacent countries has been transformed since the 1980s. This was primarily a result of the declaration of Exclusive Economic Zones(EEZs) by many coastal states in the years leading up to the close of the negotiations of the UNCLOS in 1982. Significantly, by recognizing the right of coastal states to determine how their waters were to be exploited, UNCLOS provided a legal basis and economic motivation for the negotiation of access agreements between coastal states and distant-water fishing nations, KoreaThere is a real danger that Korean distant-water fisheries agreements could and do result in the adverse environmental impacts experienced in Korean coastal waters being transferred to third country water and consequently creating socio-economic problems for these third countries. Korean distant-water fisheries agreements with third countries have the potential to be a force for good if they are well managed and if the principals that will be applied within Korean coastal waters, through the reform of the distant-water fisheries policy, are applied equally upon third country waters.

• 한국해양학회지:바다
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• 제8권2호
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• pp.132-137
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• 2003

서해 중부 연안에서의 내부파 관측을 위하여 현장 관측과 인공위성의 SAR(Synthetic Aperture Radar)센서를 이용한 관측을 함께 수행하였다. 2002년 5월 28일부터 30일까지 어청도 서쪽 10 km해상에서 thermistor chain, RCM 및 ADCP 유속계를 계류하여 관측하였으며 주변해역에 대한 CTD 관측도 수행하였다. 또한 29일 오전 6시 53분 SAR 영상을 획득하였다. 현장관측 결과 계류 지점을 통과하는 여러 개의 내부파가 관측되었고 SAR 영상에서도 관측지점 주변에서 다수의 내부파 군의 공간적인 분포를 확인할 수 있었다. SAR영상에서 관측된 내부파의 공간적인 특성과 현장 관측에서 계산된 시간적인 특성에 K-dv(Korteweg and de Vries)방정식을 적용하며 서해 중부 연안에서 발생한 내부파의 특성을 분석하였다. 이러한 내부파는 물리적으로, 군사적으로, 그리고 해양생물학적으로 매우 중요한 현상이며 서해의 중요한 여름철 특성으로 고려되어야 할 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.667-674
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• 1999

Intensive livestock production has increased dramatically in Europe since the 1960s, particularly. in Northern and Central European countries, resulting in large increases in the nutrient pollution of surface and ground waters and in atmospheric emissions of ammonia. This has arisen due to inadequate management of the large amounts manure produced, particularly where there has been insufficient land area used for efficient nutrient reuse in crop production. Nutrient pollution from intensive livestock production has progressively degraded the quality of water resources in many parts of Europe, with eutrophication of many inland and coastal waters, as well as soil acidification and ecosystem degradation. These problems have been known for many years, and although there are various international agreements on transboundary pollution, it is largely left to individual countries to set and enforce standards. Consequently, a number of different approaches are employed, although the common feature of these is to encourage farmers to use the nutrients in animal manures efficiently according to crop requirements, which also reduces the potential for accumulation in soil and subsequent loss to the environment. This paper reviews nutrient production and use in Europe and some of the strategies employed to avoid and reduce nutrient pollution.

• Animal Systematics, Evolution and Diversity
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• 제33권3호
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• pp.176-188
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• 2017

Paramenophia platysoma (Thompson and Scott, 1903) is newly reported from Korean waters based on the materials collected from several seagrass and algal bed habitats. The Korean materials of P. platysoma in the present study coincide well with the original description of the species with respects to the characteristic features of the first, fourth, and fifth legs, and in most respects to P. platysoma sensu $Gam{\hat{o}}$ (1969) reported from Japan except for the antennary exopod. However, they show some differences to P. platysoma sensu Pallares (1973, 1975) reported in Argentina, in terms of the morphology of the fifth leg in females and the second leg in males. Detailed description and illustrations of P. platysoma are provided for both sexes. The morphological features of Paramenophia species are discussed and a key to the species of genus is provided.

• 환경생물
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• 제33권2호
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• pp.119-125
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• 2015

Despite the worldwide distributions of genus Lepidepecreum and the previous reports from China and Japan, this genus has not yet been recorded in Korean waters. In this study, Korean materials of lysianassid amphipods are assigned readily to the genus Lepidepecreum and identified as L. vitjazi Gurjanova, 1962 based on the following features: well-developed dorsal keels of the pleonite 3 and urosimite 1; unconcaved palmer margin of ganthopod 1; hooked locking spines of propodus on pereopods 3 and 4; and the shape of coxa 4. We also provide the description and illustrations of this species.

• 한국해양공학회지
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• 제13권4호통권35호
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• pp.143-150
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• 1999

Multipurpose fisheries base was conceptually designed to establish marine ranching system in the coastal waters around Tongyoung, southern sea of Korea. Fisheries base for marine ranching system has integrated various facilities which were required for the process of spawning, rearing, training, releasing, monitoring and catching functions. This base has five steel piles for supporting upper structure and systems. Four steel piles are surrounded by circular net pen made by steel wire, they have the function of the protection against fouling for pile and scouring for bottom soil as well as secondary rearing and short stocking. We can use the last pile to moor a ship and access to the base. Principal structure with steel piles is designed by optimization technique considering design external forces in the coastal waters of return period of 50 years. Design optimization Problem is formulated for this base. Optimal design of multipurpose fisheries base is numerically investigated by sequential quadratic programming method.