• Journal of Plant Biotechnology
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• 제33권2호
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• pp.117-122
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• 2006

Comparative studies on medium supply in bioreactors (raft, immersion and ebb and flood) have revealed that multiplication and growth of Alocasia Amazonica were greatest in the raft system, while lowest in ebb and flood system. In the raft system, the basal part of the shoots was continuously in contact with medium, which enabled a constant uptake of nutrients as well as aeration to the explants. The number and the size of leaf stomata were higher in the raft system compared with immersion and ebb&flood system. In the immersion system, plantlets were deformed and epidermal cells in leaves were irregular with a large intercellular space. The results suggested that the medium supply should be controlled properly to maintain normal and healthy plantlets during liquid cultures in bioreactors Which affects morphology and physiology Of the plantlets.

• 한국수산과학회지
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• 제37권4호
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• pp.323-329
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• 2004

In situ particle size and volume concentration of suspended sediment was measured at the mouth of Seomjin River Estuary In February 2001, using an optical instrument, 'LISST-100'. Time variation of in situ particle size and concentration shows: (1) during ebb tide, Seomjin River supplies relatively fine-grained particles with less-fluctuated, compared to during flood tide, and well-behaved concentrations following the tidal cycle; and (2) during flood tide, relatively coarse-grained particles with highly variable in size distribution and concentration flow upstream from Kwangyang Bay. This explains a poor correlation $(r^{2}=0.10)$ between sediment concentration and beam attenuation coefficient during flood and a high degree of correlation $(r^{2}=0.80)$ during ebb tide. Relatively fine grained and well defined, monotonous size distribution may promote the correlation between concentration and beam attenuation coefficient due to optical homogeneity of particles during ebb tide. Abundance of large aggregates with time-varying size and shape distributions may be mainly responsible for variations in optical properties of the sediment during flood tide, and thus may confound the relationship between the two variables. The difference in particle sizes and shapes between flood and ebb tides can also be observed on SEM images.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.331-335
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• 2004

This study is focused to analyze the movement of thermal effluent dischargeed from nuclear power plant by season, ebb and flow, and before and after foundation of tide embankment using thermal infrared band image of 28 scenes observed from Landsat from 1987 to 2004, which is the early stage of operation of young-kwang nuclear power plant. In diffusion of thermal effluent discharge by seasons, spring and summer is spreading further than autumn and winter. It is considered to distribute widely mixed with thermal effluent discharge and hot water, which is distributed naturally along the seaside. It is known the fact that tidal currents control the direction of diffusion of thermal effluent discharge by the change of ebb and flow. Namely, it is distributed widely on the Southwest direction along the seaside by tidal currents when ebb and, it is moved widely on the Northeast direction along the seaside by tidal current when flood. However, in the early stage of flood current, the mainstream of thermal effluent discharge is spread on Southwest direction and, the direction is changed on North­east way when the latter period of flood current. Similarly, in the early stage of ebb current, the mainstream of thermal effluent discharge is spread on Northeast direction and, the direction is changed on Southwest direction when the latter period of ebb current. As the result of comparing to the diffusion pattern of thermal effluent discharge before and after the foundation of seawall, discharged thermal effluent from the drain of plant by the foundation of dike is shown as curved circle pattern on Northeast to West direction from the ending portion of the seawall.

• 한국어류학회지
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• 제28권3호
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• pp.192-199
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• 2016

조류에 의한 에너지가 상대적으로 매우 큰 한강 하구역의 대표적인 석모수로와 염하수로에서 2007년 8월과 2008년 8월에 연속 관측을 통해 조석주기에 따른 소하성 어종인 웅어속 자치어의 출현량을 조사하였다. 조석주기에 따른 환경측정 결과, $1^{\circ}C$ 미만의 수온차를 보였고, 염분은 창조 시 최고 15.1 psu, 낙조 시 최저 0.8 psu로 조석에 따른 염분차가 컸다. 웅어속 자치어는 창조 시보다 낙조 시 높은 출현량을 보였다 (p<0.05). 이는 소하성 어종인 웅어속 자치어가 한강 상류 또는 중류에서 부화한 후, 보육장인 하구역에 정착하기 위해 수평이동 선택적 조수흐름 (STST)으로 낙조류를 이용하는 것으로 사료되며, 특히 낙조 시 13.6 mm 이상의 유영력이 향상된 개체일수록 뚜렷하게 나타났다.

• Journal of the korean society of oceanography
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• 제37권1호
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• pp.10-19
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• 2002

The detailed structure of a tidal front and its ebb-to flood variation in the main tidal channel of the Kyunggi Bay in the mid-west coast of Korea were investigated by analyzing CTD data and drifter trajectories collected in late July 1999. A typical tidal front was formed in water about 60 m deep at the mouth of the channel. Isotherms and isohalines in the upper layer above the seasonal pycnocline in the offshore stratified zone inclined upward to the sea surface to form a surface front, while those in the lower layer declined to the bottom front. The location of the front is consistent with $100 S^3/cm^2$ of the mixing index H/U defined by Simpson and Hunter (1974), where H is the water depth and U is the amplitude of tidal current. The potential energy anomaly in the frontal zone varied at an ebb-to flood tidal cycle, showing a minimum at slack water after ebb but a maximum at slack water after flood. This ebb-to flood variation in potential energy anomaly is not accounted for by the mixing index. We conclude that on- and offshore displacement of the water column by tidal advection is responsible for the ebb-to-flood variation in the frontal zone.

• 생물환경조절학회지
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• 제18권2호
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• pp.107-111
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• 2009

Echinacea 청정대량생산을 위해 재배환경조절이 강한 수경재배 시스템에서 Echinacea 뿌리와 잎 생산에 적합한 수경재배 시스템을 선발하고자 실험을 수행하였다. 실험에 사용한 공시작물은 E. angustifolia DC. 와 E. purpurea (L.) Moerch이며 NFT, modified NFT, DFT, aeroponics, Ebb & Flow등 5가지 시스템을 사용하여 150일간 실험하였다. 120일 수경재배한 두 종 모두 광합성 및 증산률은 Ebb & Flow 시스템에서 유의적으로 낮은 수준을 보였다. 정식 후 150일 째 지상부 생체중과 건물중은 E. angustifi이za의 경우 분무경과 DFT에서 높았고, E. purpurea는 분무경과 NFT에서 유의성 있게 높았다. 지하부의 생체중 및 건물중은 E. angustifolia와 E. purpurea는 분무경에서 가장 높았고 다음으로 M-NFT에서 높았다 두 종 모두 뿌리의 길이는 두 종 모두 NFT 및 Ebb & Flow 시스템에서 높았고 분얼수는 E. purpurea가 분무경에서 유의적으로 높았다. 따라서 Echinacea의 바이오매스 확보를 위한 수경재배 방식으로 광합성과 지상와 지하부 생육량이 E. angustifolia 와 E. purpurea 모두 높았던 분무경 시스템을 선발하였다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.435-438
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• 2008

The huge economical damage and environmental pollution have been occurred for decades because of using of fossil fuel. So the development of alternative energy is urgent. In the west sea of Korea, a proper area for tidal power plant, development and investigation for economical efficient of tidal power plant are preceeding. The water turbine generator with the capacity of 25.4MW was used to compare single-basin flood tide generation with ebb tide generation while considering the water depth and tide in the vicinity of Sukmodo.

• 한국해안해양공학회지
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• 제17권1호
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• pp.47-54
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• 2005

목포해역과 같이 수심이 복잡하고 조간대가 광범위하게 발달되어 있는 곳의 수심자료를 용이하게 입력하고 수치모형 운용을 경제적으로 수행할 수 있는 기법을 개발하였다. 이를 청계만의 조간대 모의에 적용하여 조간대와 관련된 목포해역의 동수역학적 해석을 수행하였다. 하구언과 방조제 건설에 따라 목포항 인근을 비롯해 청계만 수역까지 조석확폭현상이 발생한 바 있는데, 이로 인해 청계만의 조간대 규모가 증대되었으며 낙조우세가 더욱 심화되었다. 청계만의 심화된 낙조우세현상은 목포항 쪽의 해수유통량 증가에 기인하였는데 이러한 영향성 증대로 인해 목포항 부근의 낙조우세 역시 심화된 결과를 초래하였다.

• 한국수산과학회지
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• 제12권1호
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• pp.71-77
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• 1979

1. 말뚝망둥어 (Periophthalmus cantonensis)의 포복도약하는 생활군의 생태를 구명하는 일환으로 1978년 7월에서 8월까지 금강을 중심으로 하기의 생활양식을 조사한바 다음과 같은 결과를 얻었다. 1. 분포는 칠산리(St. 1)에서 오식도(St. 7) 까지의 약 25km 연안선이다. 2. 서식밀도는 평균 1.5미/$m^2$이고 고조아대에서 평균 2.6미/$m^2(56\%)$, 중조아대에서 평균 1.5미/$m^2(32\%)$ 저조아대에서 평균 0.5미/$m^2(12\%)$였다. 3. 정주세력비는 : $86\%$이며 정주세력의 평균체장은 57mm, 생활권은 10m, 보행속도는 2.16mm/sec였다. 4. 말뚝망둥어는 성장함에 따라 분리, 독립하여 일정구역을 점령확보하며, 또 이를 확인시켜가는 경향이 있다. 5. 독립생활을 하던 것이 다시 모여 군집을 형성하는 경우는 특히 정주세력이 강한 고조아대에서 볼 수 있었으나 이들 단위군집내에서는 체장차이를 볼 수 없었다.

• 생물환경조절학회지
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• 제14권4호
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• pp.298-301
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• 2005

Potato (Solamum tuberosum 'Dejima') plantlets were investigated on culture type and initial quantity of inoculation in bioreactor and survival rate by hydroponics for mass production. rode stems (1 to 1.5cm in length) of potato plantlets multiplied in vitro were grown for 3 weeks in liquid Murashige and Skoog (MS) medium with sucrose $30 g\; L^{-1}$. When plantlets (80-node inoculation) were raised in 10L balloon type bubble (BB) bioreactor, the healthiest growth of plantlets was obtained from explants cultured in ebb & flow culture with medium supplied periodically 12 times per day. The suitable inoculation quantity of 20L BB bioreactor was 120 pieces of stem segments (mean 2.2g fresh weight) in ebb & flow culture. Number of nodal shoot was eight on the average. In controlled culture room, survival rate of plantlets at 7 days after stem cutting was above $70\%$ when they were acclimatized by hydroponics grown in deep flow and solid medium culture. The highest survival rate of the stem cutting plantlets was in nutrient solution adjusted to EC $1.4dS{\cdot}m^{-1}$. Stem cutting plantlets through one culture could be obtained $670\~900$, when plantlets were grown in ebb & flow culture during 3 weeks using a 20L bioreactor with initial 120 pieces of nodal segments. 11 is possible In do mass production of seedlings cultured in bioreactor and hydroponics.