• Journal of fish pathology
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• v.20 no.1
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• pp.25-31
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• 2007

Vibriosis is one of the most important diseases affecting marin fish. In this study, a bacterium belonging to the Vibrio were isolated from maroon clownfish (Premnas biaculeatus) larvae (3～7 days after hatching). The bacterium was identified as Vibrio ponticus KJS1 by 16S rRNA gene sequence analysis. The result of biochemical test using the GN2 microplate (BioLog Inc, USA) showed that it has the ability to use 35 substrates including dextrin and sucrose was detected, could not degrade 52 substrates including α-cyclodextrin, and showed the weak ability to use 7 substrates including glycogen. It was sensitive to oxolinic acid, flumequine, ciprofloxacine, ofloxacin, norfloxacin, nalidixic acid, pefloxacin, and doxycycline hydrochloride.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.438-441
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• 2003

남해 동부 연안 지역 지하수의 해수 침투 영향을 광역적으로 파악하기 위하여, 202개소의 지하수 시료를 채취하고 수리지구화학적 연구를 수행하였다. 전체 시료 중 14.4%가 500 $\mu\textrm{m}$/cm을 초과하는 높은 EC값을 나타내어 해수 영향을 시사해 주었다. 해수 영향 판단의 또 다른 파라메터로 사용되는 CI/HCO$_3$ 몰비는 전체 시료의 23.3%가 1.3 이상의 값을 나타내었다. 한편, 대표적으로 해수침투 영향 및 인위적 오염의 영향을 각각 반영하는 것으로 알려진 Cl과 NO$_3$의 농도에 관한 누적도수분포도를 작성하여 배경수질군과 오염영향군을 구분짓는 배경치(background concentration)를 구한 결과, 각각 Cl = 22.3 mg/1 및 NO$_3$= 23.1 mg/l로 나타났다. 이 두 파라메터의 농도 분포를 기준으로 하여 채취된 지하수 시료를 크게 4개의 그룹으로 나눌 수 있었다. 그 결과, 자연적 또는 인위적 기원의 오염이 배제된 그룹 1은 전체 시료의 31%, 자연적 오염(해수 영향)을 반영하는 그룹 2는 전체의 24%, 인위적 오염의 영향을 반영하는 그룹 3은 전체의 9%, 해수 영향 및 인위적 오염을 동시에 반영하는 그룹4는 전체의 36%로 나타났다. 또한 그룹2와 그룹4는 대부분 Na-Cl유형으로 진화하는 Ca-Cl유형을 나타내었다. 따라서, 여러 지구화학 방법에 의한 해수 영향 판단 결과는 서로 잘 일치하고 있음을 알 수 있다. 결국, 지구화학적 파라메터를 종합적으로 활용함으로써, 연안 지역 해수침투의 효과적인 파악은 물론 예측 및 방지, 복구에 효과적으로 사용될 수 있을 것으로 판단된다.으로 토양에서 유동 가능성이 있는 중금속만을 추출하였다. 분석실험은 토양의 Cd2+ 와 Pb2+를 대상으로 행하여졌으며, 여러 토양에서 추출 분석한 결과를 EDTA분석결과와 비교하였다. 실험결과, 중금속은 매우 신속하게 고분자 자성체와 결합하였고, 그 후 자성체를 외부 자장으로 모은 후 산으로 용해시키고, 결합된 중금속은 Graphite furnace AAS로 분석함으로써 빠르고 효율적으로 분석실험을 수행할 수 있음을 알 수 있었다. 한편, 실험에서 나타난 수치들을 비교 검토한 결과 토양 분석시 sandy soil에서는 자성체를 이용한 분석이 EDTA에 의한 방법보다 더 높은 추출도를 보인 반면, silt 함량이 많은 토양의 경우에서 EDTA분석에서 더 높은 중금속 추출도를 보였다.s 중에서 490nm와 555nm의 복합밴드를 포함하는 OC2 알고리즘(ocean color chlorophyll 2 algorithm)을 사용하는 것이 OC2 series 및 OC4 알고리즘보다 좋은 추정 값을 도출할 수 있을 것으로 기대된다.환경에서는 5일에서 7월에 주로 이 충체의 유충이 발육되고 전파되는 것으로 추측되었다.러 가지 방법들을 적극 적용하여 금후 검토해볼 필요가 있을 것이다.잡은 전혀 삭과가 형성되지 않았다. 이 결과는 종간 교잡종을 자방친으로 하고 그 자방친의 화분친을 사용할 때만 교잡이 이루어지고 있음을 나타내고 있다. 따라서 여교잡을 통한 종간잡종 품종육성 활용방안을 금후 적극 확대 검토해야 할 것이다하였다.함을 보이고 있다.X> , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.160.2-160.2
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• 2011

바다를 가로막는 방벽이나 방조제의 배수갑문 또는 조력발전소의 수문과 같이 인공 해양구조물을 통하여 흐르는 고속 해류를 이용하여 발전하는 해류발전 방식에 있어서, 고속 해류에 적합한 수차터빈과 발전기의 특성을 알아보았다. 조석간만의 차가 큰 지역에 설치되는 인공 해양구조물을 지나는 해류는 인공 해양구조물 전후에 발생하는 해수의 위치에너지 차이가 운동에너지로 바뀌면서 조석간만의 자연현상에 의해 발생되는 조류의 속도보다 훨씬 더 빠르게 흐른다. 이론적으로 우리나라의 서해안의 조석간만의 범위 3~8m로부터 7.5~12m/s 정도의 고속 해류가 가능하다. 이러한 경우에 적합한 해류발전기는 수차터빈 날개지름의 크기가 5m에서부터 12m 이하이면서, 증속기어박스와 발전기, 유압시스템 및 냉각시스템 그리고 전력변환장치를 포함하는 발전시설들을 해수면 위에 설치하는 것이 바람직하다.

• Spatial Information Research
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• v.12 no.3
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• pp.275-283
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• 2004

In order to effectively, and accurately assess seawater intrusion in coastal area, multidisciplinary data including geophysical, well logging, and hydrogeochemical data should be managed in systematical way. Such systematical management of data is critical key to improve the re-usability of the data as well as the accuracy of the assessment by means of providing a method of synthetic analysis. Therefore, for systematical management of multidisciplinary data in seawater intrusion problem, we have developed a database management system and 3-D visualization interface based on geographic information system in this, study. All geophysical survey, well logging, hydrochemical, as well as drilling, data are classified as attribute data using Microsoft Access, and joined with spatial information based on ArcView. The database management system and 3-D visualization interface to handle these data, also, developed using the script language of ArcView. We think the development of database and 3-D visualization system will improve the efficiency of data management, user-friendliness of data access, and accuracy of data analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.30-34
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• 1988

In roastal fish farms the farmers, especialy engaging in dealing with the floating cage culture, going to know about relationships between holding capacity and water quality in cage. Some of water quality managers and specialists studing physiological ecology understand that the key of water quality management concerned fish farming is budget of dissolved oxygen. This paper deals with oxygen budget in floating cage of the yellow tail farms at southern coastal area in Korea. The sampling station is located at Konli-Do fish farm near Chungmu, and the data is collected for 24 hours from 3:00 p.m. 8th September 1987. In result, the needed oxygen coming after the consumption by the rearing fish had been supplied with the tide current exchange, the sum of oxygen produced by phytoplankton photosynthesis and diffused from atmosphere are no more that $43\%$ for the needs of sea water consumption included respiration of planktons and decomposition of organic matters. The optimum holding capacity of cage is possible to compute with the calculation of minimum diurnal water exchange rate $[Qin{\cdot}V^{-1}\;(C-\bar{c})]$ through net mesh of cage.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.166-174
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• 2013

Analysis of the fish community in the Lagoon Cheongcho, Korea, was investigated in 2008 and in 2012. A total 48 species, belonging to 26 falmilies, were sampled during the period. The dominant species was Tribolodon hakonensis (75.2%), and subdominant species were Acanthogobius flavimanus (5.4%), Pungitius kaibarae (3.1%). The results of the fish ecotypes according to origin of water body was compared by surveyed year, freshwater fish was reduced, whereas those of brackish water and seawater fishes were increased. Moreover, the result of similarity analysis based on species and individuals in five lagoons were divided into 2 major groups based on their similarity, and Lagoon Cheongcho was included group 'A' with Lagoon Gyeongpo, as having a montinous inflow of seawater. Hence, according to the characterization according to the analysis of fish community, Lagoon Cheongcho has lost the characteristics of a lagoon, and oceanization is considerably progressed. Therefore, we are considering the provision of a management strategy for hydrarch succession, as well as continuous research, in order to manage the recovery of essential characteristics of the lagoon ecosystem. Hence, according to the characterization according to the analysis of fish community, Lagoon Cheongcho has lost the characteristics of a lagoon, and oceanization is considerably progressed. Therefore, we are considering the provision of a management strategy for hydrarch succession, as well as continuous research, in order to manage the recovery of essential characteristics of the lagoon ecosystem.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.402-410
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• 2013

In this study, to identify ichthyofauna of the Seomjin River, which has no barrage at estuary, and to estimate effect of estuary barrage, fish sampling was conducted at 16 study sites in mainstream of the Seomjin River from 2010 to 2012. A total of 54 species classified into 17 families were collected. Cyprinidae was the dominant family and Zacco platypus (relative abundance, RA: 47.8%) was identified as the dominant species. In total, 17 Korean endemic species (31.5%) were collected, and it is higher than the average endemic rate of Korean peninsula (22.5~25.9%). Although the relative abundance of exotic species (1.1%) was low, it is higher than the past studies (2002: 0.0%, 2009: 0.4%). Dominance index of freshwater region (St.4~St.16) was relatively higher than estuary (St.1~St.3), because Z. platypus showed high relative abundance at freshwater region. But diversity and evenness index showed contradictory results, as estuary was higher than freshwater region. The ratios of sea fish, peripheral freshwater fish and economic fish, and diversity index are higher than the Nakdong River, the Yeongsan River and the Geum River. In conclusion, to conserve the value of the Seomjin River ichthyofauna, continuous monitoring is necessary.

• Journal of fish pathology
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• v.10 no.2
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• pp.165-176
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• 1997

Water samples collected from marine fish culture system in Korea were compared for their capability to reduce the infectivity titers of HRV (rhabdovirus olivaceus), FBV(flounder birnavirus) and RVS(retrovirus of salmonid). In addition, interaction between viruses and microorganisms present in the rearing seawater was examined. The titer of HRV and RVS were reduced at $15^{\circ}C$ to less than detectable limits within 3 to 5 days using untreated samples of seawater. No reduction of infectivity was noted in bacteria-free water treated by filtration or autoclaving. Bacteria (Pseudomonas and Vibrio sp.) isolated from the water collected from a flounder culture system showed the inactivation activity of HRV.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.280-281
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• 2000

담수산 rotifer, Brachionus calyciflorus는 담수산 어류 종묘생산시 가장 널리 이용되는 초기 먹이생물로 이용이 가능하며 특히, 입이 작은 열대 관상어의 먹이로 이용되고 있다. Rotifer의 생식은 처녀생식과 유성생식을 교대로 하는 종으로색 유성생식에 의해 형성된 내구란은 종 보존용, 대량배양시 seed로 쉽게 이용될 수 있으며 환경 독성학의 실험생물로 많이 이용되고 있다. 특히 최근 해수산 rotifer, Brachionus plicatilis 내구란을 대량생산하여 Artemia cyst처럼 간편하게 부화시 어류에게 직접 먹이로 공급할 수 있는 기술 수준에 도달하였다. (중략)

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.262-272
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• 2009

Upstream behavior of glass eels was examined in an experimental eel-ladder at a laboratory of the National Fisheries Research and Development Institute from March to May in 2008. The study was made under various environmental factors and conditions affecting the upstream migration of glass eels in order to design a functional ladder that would allow the passage of glass eels. The experimental eel-ladder consisted of an upper freshwater chamber and a lower sea water chamber; glass eels in sea water can move up to the upper freshwater chamber through the slope (eel-ladder) between them. The optimal condition of the eel-ladder was estimated by comparing the number of glass eels that moved upstream depending on various conditions. Since the glass eels actively moved up the slope to river water rather than to reservoir water or tap water, the experiment was realized using river water. A significantly higher number of glass eels moved up during the spring tide than during the neap tide, and during night than during the day. Upstream movement was significantly higher during high tide than during low tide. Glass eels effectively moved up through a slope of less than $30^{\circ}$ and water-flow velocity lower than 0.4 m/sec. The fish preferred a coarser ladder bed covered with small gravels, brush or carpet.