• Title/Summary/Keyword: Red light

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Red Electrophosphorescent Organic Light-emitting Diodes Based on New Iridium Complexes. (새로운 이리듐 화합물을 이용한 적색 인광 유기 발광 다이오드)

  • Gong, Doo-Won;Kim, Jun-Ho;Lee, Kum-Hee;Yoon, Seung-Soo;Kim, Young-Kwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.73-74
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    • 2006
  • New iridium complexes that have carbonyl group were synthesized and demonstrated various red light emission in organic light-emitting diodes (OLEDs). The maximum luminance of $57000{\sim}15300\;cd/m^2$ at 15 V and the luminance efficiency of 22.8~5.6 cd/A at $20\;mA/cm^2$ were achieved respectively. The peak wavelength of the electroluminescence were at 570~604 nm and the device also showed a stable color chromaticity with various voltages.

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Effect of Light Intensity and Quality on the Growth and Quality of Korean Ginseng (Panax ginseng C.A. Meyer) III. Effects of Light Intensity on the Quality of Ginseng Plant (광량 및 광질이 고려인삼의 생육과 품질에 미치는 영향 III. 광량이 인삼품질에 미치는 영향)

  • Cheon, Seong-Gi;Mok, Seong-Gyun;Lee, Seong-Sik
    • Journal of Ginseng Research
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    • v.15 no.2
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    • pp.144-151
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    • 1991
  • This study was conducted to elucidate the effects of light intensity using polyethylene (p.E) net shading on the specific gravity, red ginseng quality, sugar and saponin contents of ginseng root. The specific gravity significantly increased in the ginseng roots grown under the P.E net shading as compared with that of common straw shading. The red ginseng quality under the P.E net shading was improved in order of 10, 5, 15, 20, 30% of light intensity and the inside cavity and inside white part decreased remarkably as compared with those of common straw shading. The ginseng roots grown under the P.E net shading at 10% and 15% light intensity showed a significant increase in the total sugar content but a significant decrease in the reducing sugar content at 15% light intensity as compared with those of common straw shading. The amount of total saponin of ginseng roots was increased under the P.E net shading at high light intensity as compared with that of common straw shading and the ginseng roots grown under the P.E net shading at 10% light intensity showed an increase in the diol group saponin but the ratio of PT/PD was decreased. Extract contents of ginseng root under the P.E net shading was higher than those of common straw shading and the roots grown under the P.E net shading at 15% and 20% light intensity resulted in a remarkable increase in extract contents.

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Effect of Light-Emitting Diode Wavelength, Light Intensity and Air Flow Ration on Optimal Growth of Pavlova lutheri and Phaeodactylum tricornutum (LED의 파장 및 광도, 공기주입이 Pavlova lutheri와 Phaeodactylum tricornutum의 최적 성장에 미치는 영향)

  • Choi, Bo-Ram;Kim, Dong-Soo;Lee, Tae-Yoon
    • KSBB Journal
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    • v.28 no.3
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    • pp.170-176
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    • 2013
  • The purpose of this study was to determine optimum condition of Pavlova lutheri and Phaeodactylum tricornutum. Detailed studies were carried out on the effects of various wavelengths of light-emitting diodes (LEDs), light intensities and air flow rations. For the Pa. lutheri, cell growth rates and maximum cell concentrations were similar regardless of wavelengths and air flow rates. Among the different light intensities, cell concentration increased when light intensity of red LED increased. For Ph. tricornutum, red LED was found to be the most effective light source, and light intensity of 3,100 Lux resulted in the most effective for the cultivation of Ph. tricornutum. Different air flow rates were tested to overcome shading effects due to denser cell concentration in the solution. Aeration of 0.8 vvm was determined to be the optimum aeration rate for the cultivation of Ph. tricornutum. Especially, five and two times greater cell concentrations of Pa. lutheri and Ph. tricornutum, respectively, were observed when air was applied.

Development of Real-Time Internal Quality Evaluation Technique for Korean Red Ginseng using NIR Spectroscopy

  • Son, J.R.;Kim, G.;Kang, S.;Lee, K.J.
    • Agricultural and Biosystems Engineering
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    • v.7 no.1
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    • pp.8-12
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    • 2006
  • This study was conducted to develop a real-time internal quality evaluation technique for Korean red ginseng using NIR spectroscopy while they were moving to be graded. Internal qualities of Korean red ginseng were defined by color, amount of white core and cavity in the red ginseng. To evaluate the internal quality, PLS (Partial Least Square) model was developed. Spectrum saturation can be occurred when most red ginseng has a sound internal quality expressed by higher light transmittance ratio, but that could not found in the ginseng of internal white core under the same light situation. And, if spectrum saturation is obtained, it is hard to identify the exact information of internal quality. In order to evaluate of the internal quality regardless of having internal normal core or white core, an integral time controlled method was used to obtain traditional spectrum. This procedure was applied in real-time process when red ginseng was moving to be graded in the line. Among the 450 samples including 223 internal normal ginsengs and 227 internal white core ginsengs, 315 ginsengs (70%) were used to develop a calibration model and 135 ginsengs were spent to validate the model. The result of quality evaluation by the model was very good showing SEP and bias were 0.3573 and 0.0310, respectively, and the accuracy was 95.6%.

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Dual Halos and Formation of Bright Elliptical and Lenticular Galaxies

  • Lee, Myung Gyoon;Park, Hong Soo
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.37.2-37.2
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    • 2013
  • Recently it turns out that simple-looking elliptical galaxies and lenticular galaxies are more complex and intriguing than expected. One of the most surprising and intriguing findings in extragalactic studies during the last two decades is a discovery that color distribution of the globular clusters in these galaxies is bimodal, suggesting that there are two subpopulations: blue and red globular clusters. We present a determination of the two-dimensional shape parameters of the blue and red globular cluster systems (GCSs) in a large number of bright elliptical galaxies and lenticular galaxies. The position angles of both and red GCSs show a correlation with those of the stellar light distribution, showing that the major axes of the GCSs are well aligned with those of their host galaxies. However, the shapes of the red GCSs show a tight correlation with the stellar light distribution as with the rotation property of their host galaxies, while the shapes of the blue GCSs do much less. These provide clear geometric evidence that the origins of the blue and red globular clusters are distinct and that these galaxies may have dual halos: a blue (metal-poor) halo and a red (metal-rich) halo. These two halos show significant differences in metallicity, structure, and kinematics, indicating that they are formed in two distinguishable ways. The red halos might have formed via dissipational processes with rotation, while the blue halos are through accretion.

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Demand-feeding and Locomotor Circadian Rhythms in the Red sea bream, Pagrus major

  • Choe Yong-Gwon;Choi Jae-Eun;Roh Duk-Whan;Choi Cheol-Young
    • Fisheries and Aquatic Sciences
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    • v.4 no.3
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    • pp.130-137
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    • 2001
  • In the present study, the locomotor and feeding activities of single red sea bream, Pagrus major were simultaneously investigated to examine the existence of such dual behaviour. Seven red sea bream of 13cm body length on average were placed individually in 35L tanks equipped with an infrared sensor and a newly developed demand-feeding device. Fish were exposed to a light: dark 12: 12h cycle and constant darkness (DD) to study endogenous rhythmicity. Under LD 12: 12 h, the daily pattern of behaviour differed between individual fish; some red sea bream were diurnal and others were nocturnal. Futhermore, some of them displayed an extraordinary flexibility in phasing because they were dark active but light feeding, and vice versa. Under DD, red sea bream showed free-running rhythms for locomotor activity and feeding. These results indicate that the type of phasing of locomotor activity did not necessarily decide the feeding phase; much of this is explained by the fact that red sea bream were demand-fed. Flexibility in phasing and a certain degree of independence between locomotor and feeding activities could be seen as an adaptative response of the highly adaptable circadian rhythms of fish.

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Microscopic Patterns of Decay caused by Tyromyces palustris and Gloeophyllum trabeum in Korean Red Pine and Radiata Pine Woods

  • Kim, Hwa Sung;Eom, Young Geun
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.5
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    • pp.1-10
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    • 2006
  • The objective of this study was to elucidate the microscopic patterns of decay caused by brown-rot fungi of Tyromyces palustri and Gloeophyllum trabeum in Korean red pine (Pinus densiflora) and radiata pine (Pinus radiata) woods through light and electron microscopies. The ultrastructural changes of cell walls attacked by the two brown-rot fungi were compared in this respect. Macroscopically, radiata pine showed more ring and radial checks than Korean red pine. Microscopically, with the progress of decay, spiral checks associated with cross-field pits and bore holes in the cell wall were more remarkably numerous in the radiata pine than in the Korean red pine. In the radiata pine, G. trabeum produced more spiral checks in the cell wall than T. palustris. In the advanced stages of decay by G. trabeum, the erosions of ray cell walls were identified both in the Korean red pine and radiata pine but $S_3$ layers of tracheid walls were eroded only in the Korean red pine.

Anatomical Characteristics of Yellow-Hearted Pine (Pinus densiflora for. erecta Uyeki) (황장목(黃腸木)의 해부학적 특성)

  • Lee, Ae-Hee;Jang, Jae-Hyuk;Park, Byung-Ho;Kim, Nam-Hun
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.56-61
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    • 2014
  • Macroscopic and microscopic characteristics of Yellow-hearted pine and Red pine were investigated. Wood color, annual ring width and latewood percentage were observed by the naked eye. Anatomical properties as the structure of three sections and cell dimensions were examined by an optical microscopy. As a result, the color of bark in Yellow-hearted pine was Reddish-grey, and Red pine showed brown or gray. The color of heartwood and sapwood in Yellow-hearted pine was deep-yellow to brown and creamy-white. And the color of heartwood and sapwood in Red pine was light-brown and light-yellow. The annual ring width of Yellow-hearted pine was narrower than that of Red pine, and the latewood percentage of Yellow-hearted pine was a little higher than that of Red pine. There was no significant difference in the anatomical characteristics between Yellow-hearted pine and Red pine.

White Light-Emitting Diodes Using Conjugated Polymer Blends

  • Hwang, Do-Hoon;Park, Moo-Jin;Kim, Suk-Kyung;Lee, Chang-Hee;Kim, Yong-Bae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.585-587
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    • 2004
  • We report the characterization of white light emitting devices fabricated using conjugated polymer blends. Blue emissive poly[9,9-bis(4'-n-octyloxyphenyl) fluorene-2,7-diyl-co-10-(2'-ethylhexyl)phenothiazine-3,7-diyl] [poly(BOPF-co-PTZ)] and red emissive poly(2-(2'-ethylhexyloxy)-5-methoxy-1,4-phenylenevinylene) (MEH-PPV) were employed in the blends. The inefficient energy transfer between these blue and red light emitting polymers (previously deduced from the PL spectra of the blend films) enables the production of white light emission through control of the blend ratio. The PL and EL emission spectra of the blend systems were found to vary with the blend ratio. The EL devices were fabricated in the ITO/PEDOT/blend/LiF/Al configuration and white light emission was obtained for one of the tested blend ratios.

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RGB White Organic Light Emitting Diode with a Color Control Layer

  • Lee, Jeong-Ik;Chu, Hye-Yong;Yang, Yong-Suk;Lee, Mi-Do;Chung, Sung-Mook;KoPark, Sang-Hee;Hwang, Chi-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1587-1590
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    • 2006
  • Through the engineering of recombination region and energy transfer in organic light emitting device, blue and red light emitting device with good color stability has been successfully obtained. A Color control layer (CCL), which emits green light through the energy transfer from the emission layers, has been introduced into the blue and red light emitting device for RGB white OLED. The RGB white OLED showed the current efficiency of 13 cd/A and the CIE coordinates of (0.33, 0.38) at $1000\;cd/m^2$. The device exhibited very stable spectrum with respect to operating current density and the CIE coordinates varied from (0.34, 0.38) to (0.31, 0.37) for $100-22000\;cd/m^2$.

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