• Journal of Sensor Science and Technology
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• v.24 no.5
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• pp.348-352
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• 2015

Thin nickel oxide films formed on uncooled and cooled $SiO_2/Si$ substrates using a radio frequency (RF) magnetron sputter powered by 200 W in a mixed atmosphere of argon and oxygen. Grazing-incidence X-ray diffraction and field emission scanning electron microscopy are used for the structural analysis of nickel oxide films. The electrical conductivity required for better bolometric performance is estimated by means of a four-point probe system. Columnar and (200) preferred orientations are discovered in both films regardless of substrate cooling. Electric resistivity, however, is greatly influenced by the substrate cooling. Oxygen partial pressure increase during the nickel oxide deposition leads to a rapid decrease in resistivity, and the resistivity is higher in the cooled nickel oxide samples. Even when small microstructure variations are applied, lower resistivity in favor of low noise performance is acquired in the uncooled samples.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.198-200
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• 2001

Grager-Induced colony formation was examined using strains of green alga Scenedemus dimorphus (Turpin) Kutzing. Alga was cultured in a medium with or without filtered water in which Daphnia magna or Moina macrocopa had been reared. Colony formation was obviously promoted in S. dimorphus by exposure to zooplankton filtered water (ZFW), showing in proportion to the volume of zooplankton filtered water in cultured media. The particle volume as well as the number of cells per one colony of S. dimorphus increased between 24 and 48 hours after exposure to ZFW, which were caused by an infochemical released from from Daphnia or Moina probably as a part of defense mechanism against zooplankton grazing.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.201-204
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• 2006

In the side scan sonar method, use is made of the back-scattering, at low grazing angles of incidence to the seabed, of relatively high-frequency acoustic waves radiated in a fan-shaped beam from a transducer contained in a towed body. The fan beam is oriented so that the wider angle is in the vertical plane (scan range) and the narrower angle in the horizontal plane (beam width) with the axis of the beam normal to the ship track. The display of the returns is usually realized as a series of closely spaced intensity-modulated lines on a paper recorder or computer screen display. In this way a two-dimensional picture of the seabed is build up.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.6
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• pp.647-650
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• 1995

The study on the sex ratios of natural population of Ixodid ticks in pasture was conducted in the Bangladesh Agricultural University Campus, Mymensingh, from 1988 to June 1990. The samples were collected from the five grazing fields consisting of five different vegetations. Dragging methods were used for the collection of samples. In 24 months of observations a total of 1113 ticks of two different species, Boophilus microplus (670), Haemaphysalis bispinosa (443) were collected and their sex ratio was determined. Females were recorded higher in both B. microplus and H. bispinosa.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.320-323
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• 2008

In this study the effect of collision model was evaluated in spray field by CFD. A collision is basically the interaction between droplets and criteria of collision is determined by drop Weber number, impact parameter, and drop-size ratio. Early developed collision model considered coalescence and grazing collision with the exchange of momentum. However in experimental research there were bouncing, coalescence, reflexive separating and stretching separating in interaction between droplets. In this study the collision considering such complex phenomena is modeled and was compared with the basic collision model.

• Journal of Microbiology
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• v.34 no.4
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• pp.300-304
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• 1996

To define the effects of zooplankton and phytoplankton to bacteria, bacterial numbers, frequency of dividing cells (FDC) and size distribution were performed with image analysis in the surface layer of Lake Soyang. In August 1992, when Anabaena was blooming, the bacterial number increased at daytime. Bacterial numbers and FDC value had a negative correlation (r = 0.83, P < 0.01). Bacterial size spectrums were dynamically changed during the day and night, especially the small bacteria less than $0.5\;{\mu}m^3$. Meanwhile, in October, after the bloom, the bacterial number was only one third of that in August, even though the FDC was higher than that in August. The bacterial numbers of small size class dropped at 13:00. But the size spectrums were relatively constant during the night time. These results suggest that the bacterial growth was tightly coupled with phytoplankton during Anabaena bloom. And after the bloom, the bacterial number was controlled grazing activity of zooplankton at daytime.

• Journal of the Semiconductor & Display Technology
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• v.9 no.4
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• pp.31-37
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• 2010

In this paper, optical deflection of laser scattering has been investigated based on Rayleigh criterion for crystalline silicon wafer in solar cell. A laser scattering mechanism is newly designed using light scattering properties in silicon wafer. Intensity distributions of laser scattering are different, depending on the incident angle of laser computed from Rayleigh criterion. In case of the incident angle satisfied with the criterion, they are asymmetric. Also, their specular reflection angle is shifted to unpredicted ones. These phenomena are in accordance with previous theories of laser scattering. The optical deflection of laser scattering is experimentally identified with the designed laser scattering mechanism. Its mathematical model is presented from the geometric relationship of laser scattering. It is shown that the optical deflection of laser scattering agree with the presented model, exclusive of grazing angles which is satisfied with Rayleigh criterion.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.1
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• pp.7-12
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• 1994

This study was undertaken to evaluate the effect of legume reseeding on legume establishment, dry matter yield, quality and botanical composition of grasses in timothy(Ph1eum prarense L.) dominated pasture at alpine area. Establishment number and percentage of legume in timothy dominated pasture were increased with spring, red clover(Tr$olium pratense L.) and gramoxone $treatment Dry matter yield of pasture was increased with fall and grazing after overseeding, but, there waq no difference in legume species. Crude protein content(%) of grasses at the first cutting was increased with red clover and paraquat (gramoxone) treatment. Based on the results, it is suggested that spring in seeding time, red clover in legume species and oveneeding after gramoxone treatment are good for effective renovation of timothy dominated pasture at alpine area.

• Journal of Environmental Science International
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• v.15 no.4
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• pp.385-386
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• 2006

In 2005, harmful dinoflagellate Cochlodinium polykrikoides was first occurred on July 18 and disappeared on September 12 in the Yeosu waters of the South Sea of Korea. During C. polykrikoides blooms, the species of Protoperidinium was isolated from Jabong Island in Yeosu in the middle of August, 2005. The surface water temperature at the sampling site was $25^{\circ}C$, and salinity was 33.1 psu. The specimen was somewhat large in size and was longer than its width. The shape was close to being ovoid, with an apical horn. This study discovered cells with colorless and transparent ingested chain-forming C. polykrikoides. However, this species was not abundant, implying low grazing impact on C. polykkoides.

• ALGAE
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• v.28 no.4
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• pp.297-305
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• 2013

There is increasing interest in the relationships between marine bacteria and red tide organisms. Some bacteria are known to kill red tide organisms, and may be responsible for accelerating the termination of red tides. Thus, certain algicidal bacteria have been proposed for the control of red tides. Meanwhile, many red tide organisms are known to feed on marine bacteria. The roles of marine bacteria and red tide organisms are therefore reversible. In Korean waters, the killing of red tide organisms by algicidal bacteria, and also the feeding of red tide organisms on marine bacteria have been extensively investigated. The findings of such studies may influence the conventional view of red tide dynamics, and also planktonic food webs. Here, we review the species and concentrations of algicidal bacteria that kill red tide organisms in Korean waters, as well as the ingestion rate and grazing impact of red tide organisms on marine bacteria. Furthermore, we offer an insight into the ecological roles of these 2 components in marine planktonic food webs.