• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.522-525
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• 2002

본 논문에서는 고휘도 LCD 백라이트 유닛에 사용되는 직하방식 백라이트 제조 방법을 이용하여 저전력, 고휘도, 경박 단소의 광고용 사인보드를 설계 제작하였다. 광학 시뮬레이션을 이용하여 램프의 배치 등 을 설계하였으며. 최고 16개의 냉음극관 램프를 구동할 수 있는 인버터를 설계 제작하였다. 크기 $500mm{\times}400mm$의 광고판의 경우 두께는 35mm 이었으며 휘도는 15,000lux이었다.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.9-13
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• 1991

The short-horned grasshoppers, Oxya sinuosa Mistshenko, were reared in the growth cabinet exposed alternately to 16 hours of artificial light (510${\pm}$240 lux) and 8 hours of darkness under the condition of constant temperature of 30${\circ}C$ and 65${\pm}$3% in relative humidity. The results obtained in this study are summarized as follows. Both female and male grasshoppers had seven instars. In the larval developmental stages of female and male, the third stage was shorter than the other stages, and the longest stage was the seventh. The total developmental period of females and males were approximately 80.17 and 63.5 days, respectively. The survivorship curve at the temperature of 30${\circ}C$ shows straight line.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.168-173
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• 2011

Recently, from a saving energy and environmental lighting sources point of view, using LED lighting have been increased rapidly. The colors of light was applied to the control of dimmers that is composed of red, green, blue, and white(RGBW) to improve the quality of visual environment. Moreover this study has been processed to develop adjustable dynamic LED lighting system on SPD and definitize the various spectral power distribution and color temperature of light through the control of the four dimmers. It is possible to combine up to $432^4$ kinds of light. Measurement of illuminance of range on working surface was as 7~l,831 lux. Application of visual environment for occupants can be expected according to control of lighting performance.

• Journal of the Korean Solar Energy Society
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• v.40 no.1
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• pp.35-47
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• 2020

Due to the large window area, the lighting environment of the educational space between the window and deep part of the room is not uniformly illuminated, and the phenomenon of glare is severe. For this reason, the daylight performance of DSC-BIPV windows was analyzed in order to improve the natural lighting in the educational sector. The method derives the correlation with natural lighting by measurement and simulation. Dynamic simulation confirmed that the average illuminance of the target space was higher at later than the early afternoon. The performance of natural lighting at 40% and 30% transmission of DSC has the effect of significantly reducing the amount of excess light in existing windows. Nevertheless, the actual average illuminance in all seasons corresponds to the standard illuminance of the educational facility, 300 Lux. In addition, the uniformity is also seen through the skylight illuminance ratio.

• Journal of Plant Biology
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• v.29 no.4
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• pp.243-254
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• 1986

The enzyme patterns and the food storage changes in radish (Raphanus sativus L. cv. Taewang) cotyledons during seedling development were studied. The radish seeds were germinated for 8 days at $25^{\circ}C$ under light (7, 000 lux) or dark condition. The lipid and protein contents per seed were 4.3 mg and 2.85 mg respectively. In 8-day-old light-grown seedling, the lipid and protein contents per cotyledon pair were 1.5 mg and 2.08 mg; in 8-day-old dark-grown seedling, they were 0.8 mg and 1.24 mg respectively. The heterotrophic phase of seedlings continued for 3 days after sowing and followed by autotrophic phase (3~6 day) and senescence phase (6~8 day). The food storage function decreased in response to time course. During heterotrophic phase, the activities of glyoxysomal enzymes (malate synthetase, isocitrate lyase, and catalase) were high at 2~3 day. Those patterns were somewhat more prominent in darkness. During the autotrophic phase, the activities of peroxysomal enzymes (glycolate oxidase and catalase) increased at 4~5 day.

• Korean Journal of Microbiology
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• v.10 no.3
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• pp.117-127
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• 1972

To study the effect of IAA on the growth of Chlorella, the alage wre cultured on the media for six days by bubbling $_{2}$ enriched air under 10K lux at 20-$25^{\circ}C$. The culture media were made by adding a concentration of $10^{-3}$M, $10^{-4}$M, and 0M(as a control) IAA to the standard media. During the period of culture, Chlorella was smapled for the given time of interval and photosynthetic and respiratory activities were measured by Warburg manometer and change of chemical components of Chlorella was determined by spectrophotometry after the Chlorella cell was fractionated by Schmidt-Thannhauser method. 1) Photosynthetic and respiratory activities were enhanced by IAA ; especially the enhancement of respiratory activity was so remarkable. 2) As to the chemical components of Chlorella, carbohydrates and amino acids were reduced a little but phosphate, RNA, DNA, and protein were increased by $10^{-3}$M IAA ; the increase of RNA, in particular, was noticable. 3) The above results suggest that the enhancement of growth of Chlorella, by IAA and ATP induced by respiratory activity accelerated with IAA enhanced RNA synthesis, resulting in an increase of protein synthesis.

• Journal of the Ergonomics Society of Korea
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• v.6 no.2
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• pp.9-18
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• 1987

The purpose of this study was to find the optimal stroke width-to-height ratio of the Korean character (Hangeul) which yields the greatest reading distance. In this study, black characters on a white background were used under 200 lux conditions in-doors, with the stroke width-to-height ratios ranging from a very thin 1:125 to heavier 1: 8.3. The criterion was the average reading distance at which three subjects (male university students) having normal visual acuity (1.2) could read the characters. Using the data obtained from the experi- ment, we analyzed the relationship between stroke width-to-height ratio and reading distance. In the case of the black characters on a white background, the greatest reading distances occurred with a range from 1:11.4 to 1:17.9.

• Korean Journal of Health Education and Promotion
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• v.3 no.1
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• pp.99-111
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• 2001

Adolescent psychosocial smoking prevention programs have been successful, but limited in the magnitude of program effects on the reduction of smoking behaviors. This is primarily due to the mixed results of independent studies with program variations. This systematic, quantitative research synthesis is designed to identify program key factors that are likely to increase program effects. The present study examined school-based psychosocial smoking prevention programs (1978-1997)among students in grades 6 to 12 in the United States. Theoretical formulations in this analysis of mediating effects posit that program impact on knowledge and/ or skills is associated with less smoking behaviors among program participants. Knowledge factors investigated in this study included health effects, social consequences, social influences, and social norms. Skill factors included affective skill, self-efficacy, assertiveness, self-control, problem solving, and refusal skill. The findings from this study highlight the importance of social consequences knowledge factor and assertive communication skill factor in decreasing adolescent smoking behaviors.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.322-327
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• 1997

Photosynthetic bacterium strain N-1 was isolated from the eutrophic wet soil and identified as Rhodospirillum rubrum. The optimum conditions for the cultivation of R. rubrum N-1 were estimated as 0.2% (w/v) of sodium acetate, 0.2% (w/v) of sodium propionate, 0.2% (w/v) of sodium butyrate in the Lasscelles basal medium at 30$circ$C, pH 7.0 under 4000 lux of the illumination. The removal efficiencies of total organic acid and chemical oxygen demand (COD$_{Cr}$) in swine wastewater were 80% and 87%, respectively, when 10% (v/v) of R. rubrum N-1 was inoculated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.505-508
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• 2001

Currently there is much interested in removing latent charge that is caused to latent image effect and blurring of obtained image as well as reduction of x-ray conversion efficiency in digital radiography system. To remove latent charge a-Se film is irradiated by light with 3500 lux using halogen lamp and optical fiber. We measured dark current and photosensitivity to analyze removing effect of latent charge, then compared with and without light erasing method. The reduction of measured signal due to latent charge effect was 32.3%, and the removal effect of latent charge by using light erase method was its 95.5%.