• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.06a
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• pp.140-142
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• 2013

최근 에너지 절감과 친환경 정책에 따라 LED조명에 대한 관심이 높아지면서 방송제작 현장에서도 LED조명의 활용이 많아지고 있다. 방송조명은 출연자의 인물을 사실적으로 재현하고, 영상의 전체적인 분위기와 느낌을 자연스럽고 감성적으로 표현하는 것이 중요하다. 특히 TV 스튜디오에서 요구되는 LED조명의 중요한 광원 특성은 연색성, 색온도, 조도의 평탄도, 색공간 균일성 등이다. 이에 본 논문은 방송현장에서 요구하는 광원특성을 기초로 제정된 TTA(한국정보통신기술협회)의 "방송용 LED조명 인증기준"에 따라서 기존의 할로겐 조명 및 국내 외 제조사별 LED조명 기구의 특성을 측정하여 비교분석 하였다.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.3 no.2
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• pp.56-62
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• 1989

자연채광에 관한 에너지 해석을 하기 위해서는 주광조도를 예측하여야 하며, 주광조도를 예측하기 위해서는 천공상태를 추정할 수 있어야만 한다. 즉, 천공상태의 최저상태나 최소설계기준을 추정할 수 있어야만 자연채광에 의한 에너지 절약을 해석할 수가 있다. 천공상태를 추정하는데에는 CIE에서 개발한 정적 천공모델이 많이 이용되어 왔다. 그러나 천공은 정적광원이 아니라 시간에 따라 동적으로 변하고 있음으로 자연채광설계에서 에너지의 영향을 평가하기 위해서는 보다 융통성이 있는 천공모델이 요구된다. 따라서 이 논문은 그동안 동적천공을 나타낼 수 있도록 개발된 비표준천공의 추정방법, 동적 천공상태의 추정방법, 주광조도와 천공휘도의 추정방법, 주광의 유용성 평가방법 등을 비교분석함으로써, 앞으로 우리나라 기후상태에 적합한 자연채광용 천공모델을 개발하는데 기초자료화하였다.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.220-227
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• 2012

This study was conducted to analyze the seeding quality of paprika and the growth and early yield after transplanting of paprika nursed under artificial light and natural light. In this study, blue LED, red LED, and white fluorescent lamps (FL) were used as artificial lighting sources. Photoperiod, average photosynthetic photon flux, air temperature, and relative humidity in a closed transplants production system (CTPS) were maintained at 16/8 h, $204{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 26/$20^{\circ}C$, and 70%, respectively. Leaf length, leaf width, leaf area, top fresh weight and dry weight of paprika seedlings, and chlorophyll content in paprika leaves nursed under LED and fluorescent lamps for 21 days after experiment were significantly affected by light treatments. As compared with the control (white FL), leaf area of paprika grown under blue LED, red LED, and natural light was decreased by 63%, 63%, and 28%, respectively. Top dry weight of paprika grown under blue LED, red LED, and natural light was 64%, 50%, and 22%, respectively, compared with the control. Number of leaves on 18 days after transplanting showed with red LED, blue LED, and natural light by 86%, 84%, and 48%, respectively, compared with the control. On 114 days after transplanting, paprika nursed under blue LED and red LED had relatively short plant height. This result might be caused that the elongation of its internodes was suppressed by the illumination of sole blue or red light. Average number of fruits per plant harvested during 4 weeks after first harvest was 3.5 with red LED, 3.3 with blue LED, 1.0 with natural light, and 2.2 with control, respectively. Early yield of paprika nursed under red LED, blue LED, natural light, and control were 453 g/plant, 403 g/plant, 101 g/plant, and 273 g/plant, respectively. Larger fruit of 136 g was harvested with red LED treatment. Even though the early yield of paprika was greatly increased with artificial lighting, but total yield was almost similar as the harvest period after transplanting in greenhouses was lengthened. From the above results, we could understand that paprika nursed under white FL, blue LED, and red LED showed good growth after transplanting and was early harvested by a week as compared to the natural light. Therefore, the white FL, blue LED, and red LED as the artificial lighting sources in CTPS could be strategically used to enhance the seedling quality, to shorten the harvest time, and to increase the yield of paprika.

• Clean Technology
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• v.16 no.2
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• pp.88-94
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• 2010

The physiological roles of various wavelength of light emitting diode (LED) on ‘Hayward’ kiwifruit experiencing after-ripening were investigated. Various wavelengths from LED light source were irradiated on kiwifruits kept in plastic bags or under open air at $25^{\circ}C$. During two weeks of storage, firmness of Hayward kiwifruits was decreased by $25^{\circ}C$ treatment than by $4^{\circ}C$ treatment. In the $25^{\circ}C$ storage condition, the firmness of kiwifruits was decreased by the treatment of 380 nm UV and 470nm white LED light source. Sweetness of kiwifruits treated with 380 nm UV LED and dark condition at $25^{\circ}C$ increased higher than $15^{\circ}$Brix. The acidity of kiwifruits under open air was decreased 52% by incubating at $25^{\circ}C$ with 660 nm red LED treatment. The acidity of kiwifruits in plastic bags was decreased 52.6, 55.6, 52.8% by the treatment of 440 nm blue, 470 nm white and 660 nm red LED light source, respectively, compared to that of kiwifruits incubated in darkness at $25^{\circ}C$. Decreased acidity irradiated by 660 nm red LED light source can be applied for regulating periods of the kiwifruit after-ripening process. LED light sources emit very narrow wavelength with a power-saving mode, therefore, the usage of these LED light source for regulating the after-ripening process can be classified as a clean biotechnology producing safe and environment-friendly kiwifruits.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.1-6
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• 2004

Recently the examples of a designing a building-lighting to which LED, a solid state Lighting, is applied are increasing in number, but the development of lighting apparatus and the techniques applied to a designing lighting apparatus frequently don't fit to a new source of light. This essay refers to the matters relevant to the techniques for designing a lighting, which are controlled with a digital technology, and the effectiveness of a "Interactive-lighting technique" which has a ductility by a sensor with developing a digital source of light module and applying it to a real designing a building-lighting . In the negative aspect that a digital technology can standardize a space for a lighting, a "Interactive-lighting Technique", which detects an analogic change of nature through a sensor and produces it, can become a new alternative one.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.170-175
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• 2005

In this study, mercury was removed by $TiO_2$ using fluorescent light and sunlight, instead of UV lamps. A reactor was specially designed to increase the $TiO_2's$ exposure to the light source and to make the rotational speed constant. The contacting surface area between mercury and adsorbents was increased by packing the adsorption bed with mixture of $TiO_2$ and glass beads. The mercury removal efficiency was more than 99% under all light sources tested in this study. The mercury removal efficiency was more than 99% under the fluorescent light or sunlight which is harmless and cheap or free.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.13 no.2
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• pp.29-35
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• 2004

최근 심미적인 보철 치료에 대한 사람들의 관심이 높아짐에 따라 자연치와 더욱 조화롭게 보철 치료를 하는 것이 요구되고 있다. 이는 구조적인 심미성과 함께 자연스러운 색조 재현을 통하여 이루어지는데, 자연치의 색조는 매우 다양하고 부위별로 달라질 수 있기 때문에 단순히 shade guide상의 비교만으로는 정확한 색조를 얻기가 어렵다. 이러한 색조 선택의 부정확성 때문에 객관적으로 색조를 분석하는 많은 기계적 장치들이 고안되었고, 최근에 ShadeScan system(CYNOVAD, Canada), Vita Easyshade system(Vident, Canada) 등 디지털로 색조를 평가하는 시스템이 각광을 받고 있다. ShadeScan system은 한 번의 클릭으로 치아 이미지를 채득할 수 있고, 바로 컴퓨터를 통해서 이를 분석하여 원하는 shade map, translucency map 등을 얻을 수 있다. 또한 세 방향에서 조사되는 빛은 자체 calibration을 거쳤기 때문에 주변 광원이나 환경의 영향 없이 객관적으로 치아의 이미지를 채득할 수 있다고 한다. 사실 그 동안 이미지 채득이 객관적이라고 주장하는 많은 system이 있었지만 임상의들은 그 신뢰성에대해 의구심을 보였던 것이 사실이다. 이에 본고에서는 ShadeScan system이 반복 촬영 시 같은 색조재현을 할 수 있는지 실험하여 그 객관성에 대해 살펴보았다.

• Journal of the Speleological Society of Korea
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• no.64
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• pp.13-26
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• 2004

In this paper, it was studied to investigate and apply the optimal method for well-management of cave with use of solar-cell power source and electro-luminescent tape of illuminating equipment of flat light - lamp for build up the pro-environmental management system of the long way cave on the mountain or the others.

• Electronics and Telecommunications Trends
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• v.28 no.5
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• pp.11-23
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• 2013

OLED 조명은 얇고 가볍고 열이 나지 않은 이점을 가질 뿐만 아니라 형광등 절반의 전력으로 같은 밝기가 구현 가능하여 저전력 조명기구가 가능하게 될 것이다. 또한 태양광에 가까운 균일한 면광원으로 부드러우면서 자연스러우면서 다양한 모양의 등 기구 제작이 가능한 차세대 조명이다. 본고에서는 OLED 조명의 발광원리와 특징, OLED의 고성능화를 위한 고효율 재료기술, 광추출 기술, 백색 OLED 기술, 봉지기술 등에 관하여 기술하였다. 또한 OLED 광원 산업체의 동향을 한국을 중심으로 일본업체, 대만/중국업체, 미국업체, 유럽업체 순으로 살펴보았다. OLED 조명은 2020년에 이론적인 발광 효율인 200lm/W가 구현이 되면 일상생활의 조명이 획기적으로 변화되는 사회를 맞을 것으로 기대되므로, 전 세계적으로 시장형성 초기단계이므로 선제적이고 전주기적인 지원을 통하여 시장선점 및 확대가 필요하다.

• Journal of the Korea Computer Graphics Society
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• v.17 no.2
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• pp.11-16
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• 2011

In computer graphics, shadows play a very important role as a hint of inter-object distance as well as themselves in terms of realism. To represent shadows, some traditional methods such as shadow mapping and shadow volume have been frequently used for the purpose. However, the rendering results are not natural since they assume the point light. On the contrary, an area light can render soft-shadows, but its computation is too burdensome due to integral over the whole light source surface. Many alternatives have been introduced, back-projection of occluder onto the light source to get visibility of light or filtering of shadow boundary by calculating size of penumbra. But they also have problems of light bleeding or ringing effects because of low order approximation, or low performance. In this paper, we describe a method to improve those problems using shadow atlas.