• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.817-822
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• 2000

A proper flashing light is expected to enhance microalgal biomass productivity and photosynthetic efficiency. The effect of flashing light on high-density Chlorella kessleri (UTEX 398) cultures was studied using light-emitting diodes. A frequency modulator was designed to flash LEDs, and the device successfully provided wide range of frequencies and various duty cycles of flashing. A relatively high frequencies of 10, 20 and 50 kHz were used in this study. These frequencies have very short flashing time ($2-50{\mu}s$), which corresponded to the time constant of the light reaction of photosynthesis. The specific oxygen production rates of photosynthesis under flashing light were compared with those under an equivalent continuous light in specially designed illumination cuvette. The specific oxygen production rates under flashing light were 5-25% higher than those under the continuous light. A range of cell concentration was discovered, where the benefit of flashing light was maximized. The photosynthetic efficiency was also higher under flashing light with frequencies of over 1 kHz, which was a clear indication of flashing light effect and the degree of mutual shading could by overcome by flashing lights, particularly at high-density algal cultures.

• 한국실내디자인학회논문집
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• 제15권3호
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• pp.65-74
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• 2006

This study is intended to analyze the way of incorporating the effect of natural light into the architectural space design by Le Cobusier. The composition of modem architectural space is significantly different from that of classical architecture. Such transition is attributable to the change of tectonic method which was supported by the development of new materials and structural systems. In addition, the effect of natural light systems which is one of the main elements in architectural space has undergone significant changes in modern ages. Moreover, Le Corbusier introduces the new concept of natural light in his works. By bringing the above two trends together, this study analyzed the way how Le Cobusier applied light effect in his works. Specifically, findings regarding the 'traffic flow in the space' with the light, 'elevation effect' with the 'Brise soleil' in Le Cobusier's works were presented. And also the way of lighting the object in the space was presented.

• 대한화장품학회지
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• 제46권4호
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• pp.383-390
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• 2020

블루라이트는 380 ~ 450 nm 사이의 파장에 존재하는 파란색 계열의 빛으로 활성산소를 유발하여 노화를 불러일으키는 것으로 보고되었으며, 이에 따라 블루라이트 차단 효과에 대한 관심이 높아지고 있다. 본 연구에서는 자외선 차단제품에서 오일의 극성도, 제형의 점도, 유화제의 종류, 유화입자, 무기자외선 차단제 등이 블루라이트 차단 효과에 미치는 영향에 대해 조사해 보았다. 그 결과 오일의 극성도가 유기자외선차단제의 극성과 유사해질수록 블루라이트 차단율이 높아지는 것으로 확인되었으며, 제형의 점도가 증가할수록 높은 블루라이트 차단율을 나타냈다. 유화제의 종류 및 유화 입자는 블루라이트 차단 효과에 미치는 영향이 미비하였고, 무기자외선 차단제 함유 여부가 블루라이트 차단율에 큰 영향을 주는 인자 중 하나로 나타났다. 이러한 결과들은 블루라이트 차단 효율을 효과적으로 높일 수 있으며, 앞으로 블루라이트 차단 제품 개발 및 제형 연구에 활용될 수 있을 것이다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.953-956
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• 2009

We have investigated the effect of light on amorphous silicon thin film transistors based photo-sensor applications. We have analyzed the instability caused by electrical gate bias stresses under the light illumination and the effect of photo-induced quasi-annealing on the instability. Threshold voltage ($V_{TH}$) under the negative gate bias stress with light illumination was more decreased than that under the negative gate bias stress without light illumination even though $V_{TH}$ caused by the light-induced stress without negative gate bias was shifted positively. These results are because the increase of carrier density in a channel region caused by the light illumination has the enhanced effect on the instability caused by negative gate bias stress. The prolonged light illumination led to the recovery of shifted VTH caused by negative gate bias stress under the light illumination due to the recombination of trapped hole charges.

• 한국실내디자인학회논문집
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• 제23권5호
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• pp.25-32
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• 2014

The purpose of this study is to analyze the expression method and visual characteristics of material utilized the lighting in terms of a visual aspect. The method of study is to establish standards for analysis and to classify type of visual effect and expression of that focused on preliminary study. And It is to grasp the visual expression characteristics of new materials. through analysis standards. The results of the study are as follows. First, 'decorativeness', 'symbolization', 'motion-images' and 'interactivity' were selected as the type of visual expression through the precedent studies. And it was classified the visual effects as 3 types like 'a light-emitting effect', 'steric effects' and 'movement effect'. Second, We could know that 'light-emitting effect' was expressed in 7-new materials, 'three-dimensional effect' was expressed in 3-new materials, and 'motion effect' in 4-new materials. Through that. We could know that the new materials represented with 'light-emitting effect' are much more than the other new materials. Third, the results of this study show that 'decorativeness' in the visual types was appeared to 'light-emitting effect' and 'three-dimensional effect'. 'symbolization' to 'light-emitting effect' and 'motion effect', 'motion-images' to 'three-dimensional effect' and 'motion effect' and 'interactivity' to 'light-emitting effect', 'three-dimensional effect' and 'motion effect'. And It was appeared to three effects in 'interactivity'. We could know that it is more effective to be presented the visual effect simultaneously to communication with the visual perception.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.904-911
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• 2019

Objective: The study was conducted to evaluate the effects of night light regimen on growth performance, antioxidant status and health of Lingnan Yellow broiler chickens from 1 to 21 days of age. Methods: A completely randomized factorial design involved 2 photoperiods (constant lighting [CL], 24 L:0 D and intermittent lighting [INL], 17 L:3 D:1 L:3 D)${\times}2$ light intensities (10 lx and 30 lx). A total of one thousand six hundred and eighty 1-d-old Lingnan Yellow broiler chicks were randomly divided into 4 treatments with 6 replicates (70 birds per replicate). The experiment lasted for 21 d. Results: Photoperiods and light intensities had no effect on average daily gain, feed conversion ratio, and mortality of the broiler chickens (p>0.05). The INL had a significant effect on average daily feed intake (p<0.05) of broiler chickens compared with CL. Photoperiod and light intensity had an interactive effect on melatonin (MT) concentration (p<0.05). At CL, reducing light intensity increased MT concentration; INL birds had higher MT but MT concentration was not affected by light intensity. There was an interactive effect on glutathione peroxidase (GPx) and catalase (CAT) in serum and total antioxidant capability (T-AOC) in liver between photoperiod and light intensity. With the decrease of light intensity, the activities of GPx and CAT in serum and T-AOC in liver increased in CL group (p<0.05). Broiler chickens reared under INL had better antioxidant status and 10 lx treatments had higher activities of CAT in serum than 30 lx (p<0.05). Different photoperiods and light intensities had no effect on malondialdehyde. There was an interaction between photoperiod and light intensity on serum creatine kinase (CK) concentration (p<0.05). At CL, the elevated light intensity resulted in an increase in CK content; INL birds had lower CK concentration especially in low light intensity group. Besides, INL and low light intensity significantly reduced the concentration of serum corticosterone and heat shock protein 70 (p<0.05). Serum immunoglobulin M contents were increased in broiler chickens reared under the INL compared with CL group (p<0.05). Conclusion: Results above suggest that the night light regimen of INL and 10 lx could be beneficial to the broiler chickens from 1 to 21 days of age due to the better health status and electricity savings.

• Journal of the Optical Society of Korea
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• 제18권1호
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• pp.9-14
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• 2014

We numerically investigate the effect of sunlight polarization on the absorption efficiency of V-shaped organic solar cells (VOSCs) using the finite element method (FEM). The spectral distribution of absorbance and the spatial distribution of power dissipation are calculated as a function of the folding angle for s-and p-polarized light. The absorption enhancement caused by the light-trapping effect was more pronounced for s-polarized light at folding angles smaller than $20^{\circ}$, where s-polarized light has a relatively larger reflectance than p-polarized light. On the other hand, the absorption efficiency for p-polarized light is relatively larger for folding angles larger than $20^{\circ}$, where the smaller reflectance at the interface of the VOSC is more important in obtaining high absorption efficiency.

• 융복합기술연구소 논문집
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• 제1권1호
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• pp.29-33
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• 2011

This study is performed to investigate the effect of the artificial light for room lightening. To do that, the experiments were done using the black room with 1m3 and performed to show the effect of the length between the room and light source and light intensities as LUX. The LUX of 18 sites in the room was measured using LUX meter. The length between the room and the light source was chosen as 500mm, 1000mm, and 1500mm and the light intensities was 3 levels. The results were shown the distinct difference between the part directly projected through the light path and non-directly projected. So, the light delivery path have to be modified for next step research. The results were very sensitive for the part directly projected through the light path. This study showed the basic results for room lightening using light source to simulate the solar lightening and was worth in a strict sense as fundamental study.

• 조명전기설비학회논문지
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• 제28권3호
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• pp.7-13
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• 2014

As issues on light pollution is being raised recently, movements to prevent light pollution is being implemented by each local government, such as by enforcing the Light Pollution Act from February 2013, in order to require compliance with the light-emitting permission level of existing lighting facilities. However, despite the regulations, no specific measures on products are being prepared. Thus, this Research has designed a light shield as a measure to minimize the burden of the effectiveness and time required for development and the burden of the cost necessary to re-install existing light facilities in its entirety and reviewed the effect of the measure through the BUG ratings.

• 과학교육연구지
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• 제44권1호
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• pp.112-121
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• 2020

광전효과는 빛의 입자성을 설명하는 대표적인 현상으로 고전 물리학에서 현대물리학으로의 전환을 이끈 중요한 주제이다. 중등교육 과정에서도 광전 효과를 중요하게 다루고는 있지만, '빛의 세기'에 대한 설명이 전자기파의 세기에 대한 설명과 달라서 교사나 학생들이 종종 혼란을 겪고 있다. 이에 본 연구에서는 현대물리 교재의 광전효과 단원에서 '빛의 세기'를 어떻게 설명하고 있는지 분석하였다. 널리 사용되는 10종의 현대물리 교재를 분석한 결과 '빛의 세기'가 크게 두 가지 유형으로 설명되고 있었으며, 특히 한 교재 내에서 두 가지 다른 유형의 표현이 모두 나타나기도 하였다. 연구자들은 본 연구의 결과를 바탕으로 향후 광전효과를 기술하는 데 있어서 몇 가지 유의점을 제안하였다.