• Title/Summary/Keyword: Quantity of Light

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A study on improving the surface structure of solar cell and increasing the light absorbing efficiency - Applying the structure of leaves' surface - (태양전지 텍스처 표면구조 개선 및 빛 흡수효율 향상에 관한 연구 - 식물 잎의 표면구조 적용 -)

  • Kim, Taemin;Hong, Joopyo
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.11a
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    • pp.38.2-38.2
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    • 2010
  • Biomimetc is a new domain of learning that proposes a solution getting clues from nature. There seems to be a sign of this phenomenon in fields of Renewable Energy. Foe example, Wind power was imitate the whale's fin that was improve efficiency of generating energy. This study focused on the photovoltaic generation as the instance of applying biomimetic. Efficiency is the most important factor in field of Photovoltaic generation. When given solar cell taking the sun light, most important fields of the study are absorb more light and increase the quantity of generation. For improving efficiency, the solar cell were builded up textures of taking a pyramid form, such a surface structure taking a role for remaining the light. This effects do the role as increasing absorbing efficiency. Such phenomenon calls Light Trapping, locking up the light on the surface of solar cell for a long time. Light is a vital factor to plants in the nature. Plants grow up through the photosynthesis that absorbing light for growth and propagation. So, plants make a effort how can absorb more the light in poor surroundings. This study set up a goal that imitates the minute surface structure of plants and applies to the existing solar cells's surface structure, so it can improve the efficiency of absorbing light. We used Light Tools software analyzing geometrical optics to analyze efficiency about new designed textures on the computer. We made a comparison between existing textures and new designed textures. Consequently, new designed textures were advanced efficiency, absorbing rates of light increasing about 7 percent. In comparison with existing and new textures, advancing about 20 percent in the efficient aspect.

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The Comparison of hospitalization time of Patients According to Natural Light in Hospital (병실의 자연광 환경에 따른 환자들의 입원기간 비교)

  • Kim, Hyoung-Sup;Kim, Min-Sung;Lee, Ju-Yoon;Song, Kyoo-Dong
    • KIEAE Journal
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    • v.5 no.2
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    • pp.35-41
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    • 2005
  • This study was conducted to identify the effect of daylighting in hospitals on hospitalization time of patients and patients' outcomes in hospitals. Two major variations include orientation of hospital wards and the hospitalization times of various kinds of patients. Patients' data were obtained from two hospitals located in Seoul, Korea. The hospital buildings have north-facing and north-facing wards. The patients were classified according to the types of diseases and the orientation of the patient rooms. Then, statistical T-tests were applied in order to verify if natural light might shorter the hospitalization time of patients. The study also identified the types of diseases that were more responsive to the quantity of natural light in patient rooms. This information may be used as a basis for the development of guidelines for patient rooms in hospitals to achieve more effective healing environments. Likewise, the results may be applied to medical treatment buildings, recreational centers and hospital as well.

A Study on Efficient Control of Backlight LED for Reduction of Power Consumption of LCD TV (LCD TV의 소비 전력 절감을 위한 백라이트 LED의 효율적인 제어에 관한 연구)

  • Kang, Sung-Jin;Jung, Hye-Dong
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.9 no.3
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    • pp.80-85
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    • 2010
  • In this paper, we present an algorithm for efficient control of backlight LED in order to reduce the power consumption of LCD TV. In addition, a pragmatic implementation method is presented. In conventional local dimming control, backlight LEDs of LCD TV are divided into $M{\times}N$ blocks. And, the proper luminance for each block is computed according to input image and used for dimming control. But, LED light of each block is diffused and affects the neighboring blocks, so that luminance of each block becomes larger than that of intent. In the proposed algorithm, dimming control values are reduced by the amount of quantity affected by the neighboring blocks using light spread function, resulting in additional reduction of power consumption.

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Development and Performance Property Investigation of Lighting System using Plastic Optical Fiber (플라스틱 광섬유를 이용한 조명시스템 개발과 특성 분석)

  • Shin, Sang-Uk;Yi, Chin-Woo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.12
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    • pp.25-32
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    • 2010
  • Compared to general lighting method, the lighting system that uses optic fiber can provide only the visible light of good quality to subject by eliminating ultraviolet ray and infrared ray. Thanks to this merit, it is possible to prevent the hard phenomenon of subject caused by ultraviolet ray and infrared ray and to provide the agreeable light environment. This study developed indoors illumination system of high color rendering on the basis of plastic optic fiber with excellent optical property and processing to substitute halogen lamp which has been used for excellent color rendering in spite of low efficiency and short life. Producing pilot product of the designed illumination system and evaluating the property of electric and optical property, ultraviolet ray radiation quantity and temperature property, this study verified the excellence of suggested lighting system of plastic optic fiber.

Sulfuric acid and Hydrochloric acid resistance properties of Light Weight Matrix Based on Blast furnace slag (고로슬래그 기반 경량 경화체의 황산 및 염산 저항 특성)

  • Kim, Weon-Jeong;Lee, Seung-Ho;Park, Sun-Gyu;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.11a
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    • pp.137-138
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    • 2015
  • The use of the cement and increased with the recent development of the construction industry. If the cement is the environmental problems caused by generating a large quantity of CO2 and the production process. Accordingly, this study is the test to determine the sulfuric acid and hydrochloric acid resistance properties of the Light weight matrix product of blast furnace slag-based light. A result, the compression strength of the sulfuric acid and hydrochloric acid immersion showed alower strength than the Plain.

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Color Sensing and Signal Transmission Diversity of Cyanobacterial Phytochromes and Cyanobacteriochromes

  • Villafani, Yvette;Yang, Hee Wook;Park, Youn-Il
    • Molecules and Cells
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    • v.43 no.6
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    • pp.509-516
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    • 2020
  • To perceive fluctuations in light quality, quantity, and timing, higher plants have evolved diverse photoreceptors including UVR8 (a UV-B photoreceptor), cryptochromes, phototropins, and phytochromes (Phys). In contrast to plants, prokaryotic oxygen-evolving photosynthetic organisms, cyanobacteria, rely mostly on bilin-based photoreceptors, namely, cyanobacterial phytochromes (Cphs) and cyanobacteriochromes (CBCRs), which exhibit structural and functional differences compared with plant Phys. CBCRs comprise varying numbers of light sensing domains with diverse color-tuning mechanisms and signal transmission pathways, allowing cyanobacteria to respond to UV-A, visible, and far-red lights. Recent genomic surveys of filamentous cyanobacteria revealed novel CBCRs with broader chromophore-binding specificity and photocycle protochromicity. Furthermore, a novel Cph lineage has been identified that absorbs blue-violet/yellow-orange light. In this minireview, we briefly discuss the diversity in color sensing and signal transmission mechanisms of Cphs and CBCRs, along with their potential utility in the field of optogenetics.

Antimicrobial Effect on Streptococcus mutans in Photodynamic Therapy using Different Light Source (광원의 종류에 따른 광역동 치료시의 Streptococcus mutans에 대한 항균 효과)

  • Kim, Jaeyong;Park, Howon;Lee, Juhyun;Seo, Hyunwoo;Lee, Siyoung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.45 no.1
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    • pp.82-89
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    • 2018
  • In a photodynamic therapy, the difference of antibacterial capacity was compared according to the type of source of light when the same quantity of energy is irradiated. After S. mutans is formed in planktonic state and biofilm state, erythrosine diluted to $40{\mu}M$ was treated for 3 minutes, and as the type of light source, Halogen, LED, and Plasma arc were used, which were irradiated for 30 seconds, 15 seconds and 9.5 seconds, respectively. After the completion of the experiment, CFU of each experiment arm was measured to compare the photodynamic therapeutic effects according to each condition. The CFU of each experiment arm had no statistically significant difference. Under the same quantity of energy, the photodynamic therapeutic effect can be said to be the same regardless of types of light source, which is a useful result in the clinical field with various light irradiators.

A Basic Study on Performance Evaluation of Permanent Supplementary Artificial Lighting of Interior(PSALI) using a LED Light Source (LED광원을 이용한 실내상시보조인공조명(PSALI)의 성능평가에 관한 기초적 연구)

  • Lee, Jin-Sook;Kim, Byoung-Soo;Kim, So-Yeon;Jung, Young-Gyu
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.4
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    • pp.16-23
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    • 2011
  • Since the first lighting light source was invented, lighting has turned into superior-quality lighting considering the amenity of occupants, and the characteristics of a light source has developed rapidly. So this research confirmed the lighting performance of a dimmer control system and an ON-OFF control system via the existing light source, and analyzed the basic lighting environment of Permanent Supplementary Artificial Lighting of Interiors(PSALI) through the physical comparison and evaluation of a LED lamp substituted for a fluorescent lamp used in a dimmer control system, showing that the lighting physical quantity characteristics of an ON-OFF control system and a dimmer control system are similar to each other and that they are effective in terms of energy saving. Besides, it was shown that introducing a LED light source to a dimmer control system improves lighting environments and largely reduces energy consumption.

Two-Dimensional Dimming Algorithm using Light Spread Function (빛 확산 함수를 이용한 이차원 디밍 알고리즘)

  • Jung, Hye-Dong;Kang, Sung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.8B
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    • pp.1204-1210
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    • 2010
  • In this paper, in order to reduce the power consumption of LCD TV, we present a two-dimensional dimming algorithm for LED BLU(Backlight Unit) using light spread function and a pragmatic implementation method. In conventional two dimensional dimming algorithms, LED BLU is divided into MxN blocks and proper backlight luminance for each block is computed according to input image and used for dimming control. But, LED light of each block is diffused and affects the neighboring blocks so that luminance of each block becomes larger than that of intent. In the proposed algorithm, dimming control values are reduced by the amount of quantity affected by the neighboring blocks using light spread function, resulting in additional reduction of power consumption.

A Forecasting on the Market Size of Korean Solar Salt (한국 식용 천일염 시장규모 전망에 관한 연구)

  • Choi, Byung-Ok;Kim, Bae-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.4812-4818
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    • 2013
  • This paper contains material of the supply-demand forecasting of solar salt for food in Korea. The solar salt was granted admission for food by the act of salt management in 2007. So, the yearly statistics of solar salt for food are not enough to forecast the supply-demand unsing econometrics. However, the related industry become interested in market size of the solar salt for food and the growth potential of the market. This study deal with the supply-demand forecasting of solar salt for food in light of industry of solar salt, consumption trends, export-import quantity, etc. This research results indicate that the production quantity will be 222-384 thousand MT, the export quantity will be 498-565 thousand MT, the export quantity will be 2.67-3.62 thousand MT, the consumption quantity will be 767-996 thousand MT.