• Title/Summary/Keyword: Light Control

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Flowering Control Using by Red Light of Perilla (적색광을 이용한 들깨의 개화조절)

  • Hong, Seung-Chang;Kwon, Soon-Ik;Kim, Min-Kyeong;Chae, Mi-Jin;Jung, Goo-Bok;Kang, Kee-Kyung
    • Korean Journal of Environmental Agriculture
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    • v.31 no.3
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    • pp.224-228
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    • 2012
  • BACKGROUND: This experiment was conducted to investigate the effects of red light on inhibition of flowering and vegetative growth of perilla (Perilla Frutescens. L). METHODS AND RESULTS: To determine red light intensity for inhibiting floral induction of perilla 6h light plus daylength extension (17:00-23:00) with three different intensity of red lights 0.046, 0.114 and $0.177{\mu}mol/m^2/s$ were treated respectively, and control plants were grown under 11(06:00-17:00)/13(17:00-06:00)h light/dark environment. Red(660nm) and far-red(730nm) light were irradiated for night break treatment subsequently to investigate photoreversible flowering response of perilla 'Manchu'. The flowering was inhibited by night break with red light, but sequential far-red light induced floral induction of perilla. Perilla not flowered by red light intensity over $0.177{\mu}mol/m^2/s$. Red light of $0.2{\mu}mol/m^2/s$ was irradiated for 6 hours (20:00-02:00) with LEDs device in plastic house. Perilla not flowered and continued the vegetative growth by red light treatment and the plant length, number of leaves, fresh weight, and leaf area of perilla were increased by 3%, 7%, 21%, and 19%, respectively, compared to incandescent control. CONCLUSION: These results showed that red(660nm) light for daylength extension could be used to control flowering and to enhance production of perilla leaf.

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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EFFECT OF ANTE-MORTEM STRESS ON POST-MORTEM CHANGES OF TITIN I (α-CONNECTIN) INTO TITIN II (β-CONNECTIN) AND NEBULIN IN THE LIGHT AND DARK MUSCLE OF TAIWAN COUNTRY CHICKEN

  • Lin, L.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.3
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    • pp.405-411
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    • 1994
  • Purified myofibrils were prepared from ante-mortem stress and control lots of Taiwan country chicken breast and thigh muscles at death and afler storage at $4^{\circ}C$ for 0, 1, 2, 3, and 7 days post-mortem. Sodium dodecyl sulfate polycrylamide gel electrophoresis (3.2%) and densitometer were used to examine the effect of ante-mortem stress and control storage of muscle on titin and nebulin. Results indicated that titin and nebulin were more rapidly degraded in the control and the ante-mortem stress light muscles than in the control and ante-mortem dark muscles of Taiwan country chicken. In contrast, nebulin was shown to be more resistance to degradation in the ante-mortem stress dark muscle than in the control light muscle.

Flight Test of Pitch Control Force for an Airplane (항공기 피치 조종력 비행시험)

  • Lee, Jung-hoon
    • Journal of Aerospace System Engineering
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    • v.8 no.3
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    • pp.20-26
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    • 2014
  • This paper presents the procedures and the results of the pitch control force via flight test for a light airplane in order to make out the stability of the aircraft and the compliance with concerned regulation. The flight test procedures were determined in order to obtain the aircraft type certification. The instrumentation equipments including airspeed indicator, accelerometer, and pitch control force measurement tools are used to perform the flight test. For the flight test, the airspeed and the pitch control force with related normal acceleration are measured sustaining turn flight with bank angle derived from trim speed. The flight test results showed that the handling qualities of the airplane are complied with the KAS-23, the regulation of the Korean government for the light airplane type certification.

Effects of Sulfite on Chl Fluorescence in Barley(Hordeum vulgare L.) Seedlings in Light and Dark

  • Sook, Chung-Hwa;Park, Kang-Eun
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.1
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    • pp.11-21
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    • 1999
  • The effect of sulfite on barley seedlings was investigated through Chl content, the electron transport activity of the photosystem, and Chl fluorescence. Barley leaves were harvested every 12 hrs during greening periods, and were then treated with a sulfite solution in either light or dark conditions. In both cases, the Chl content decreased in comparison with the control at any greening period. After sulfite treatment in the light, the activity of PS I decreased slightly, yet that of PSII showed a decrease of about 15%. The values of Fv, qP and qE decreased, however, the value of ql increased compared with the control. In addition, the value of qE decreased in leaves greened more than 12 hrs compared with that of the control. This indicates that the photosynthetic complex involved in energy dependent fluorescence quenching is undeveloped in a 12 hrs greened leaf, accordingly, it was a hardly affected by sulfite. After sulfite treatment in the dark, the activities of PSII and PSI decreased slightly, there was a small change in the value of Fv, qP decreased, and qE and the ratio of qNP/q increased in comparison with the control. As a result, PSII and PSI were not inhibited, however, the redox of QA was inhibited, and the excited energy was lost through the nonphotochemical pathway. The effects of sulfite in light or dark conditions were not considerably different with the Chl fluorescence quenching analysis method. In both light and dark conditions, the value of qP significantly decreased with sulfite compared to that of the control. This implies that the redox of QA was inhibited by sulfite in both light and dark contions.

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Effects of Enhanced Light Transmission Rate During the Early Growth Stage on Plant Growth, Photosynthetic Ability and Disease Incidence of Above Ground in Panax ginseng (생육 초기에 투광량 증가가 인삼생육 및 지상부 병 발생에 미치는 영향)

  • Mo, Hwang Sung;Jang, In Bae;Yu, Jin;Park, Hong Woo;Park, Kee Choon
    • Korean Journal of Medicinal Crop Science
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    • v.23 no.4
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    • pp.284-291
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    • 2015
  • This study was performed to investigate the effects of enhanced light transmission on plant growth, photosynthetic ability, and disease tolerance to leaf blight, anthracnose in ginseng (Panax ginseng C. A. Meyer, Araliacease family) during the early growth stage (April to June). The photosynthetic ratio, stomatal conductance, and stem diameter of plants grown under a shade net with 15% light transmission rate showed an increasing trend compared to the control plants (5% light transmission rate) although the growth of the aerial parts were not influenced significantly. Plant height, stem length, and leaf length of treated plants were not significantly different from those of the control plants. Root parameters, such as root length, diameter, and weight of treated plants increased significantly compared to the control. Yield performance ($187.4kg{\cdot}10a^{-1}$) of treated plants was 55.5% higher than that of the control ($150.4kg{\cdot}10a^{-1}$). Additionally, disease severity scores of treated plants were lower than those of the control plants, revealing higher survival rates. To retain high yield potential and enhance the level of disease tolerance in ginseng, we suggest the increase of light transmission rate during the early growth stage.

Visible Light Communication with Color and Brightness Control of RGB LEDs

  • Choi, Kyungmook;Jang, Yunseon;Ju, MinChul;Park, Youngil
    • ETRI Journal
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    • v.35 no.5
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    • pp.927-930
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    • 2013
  • We propose a visible light communication system in which the color and brightness are controllable. Pulse width modulation and variable pulse position modulation (VPPM) schemes are used to control the color and brightness, respectively. A digital algorithm to decode VPPM signals is suggested and implemented. A seamless transmission is observed in a testbed experiment under various environmental conditions. The proposed scheme can be applied to emotional-lighting-based wireless optical communication.

Development of efficient Web-based Light Facility Control and Management System (효율적인 Web기반 조명시설 제어 및 관리 시스템의 개발)

  • Chang, Byong-Kun;Jeon, Chang-Dae
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.11a
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    • pp.347-350
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    • 2004
  • In this paper, PDA(Personal Digital Assistants) terminal is proposed to be used for controlling and managing light facilities efficiently by connecting it to a web-based server system and adding additional functions. The control box of current light facilities may be implemented based on a simple On-Off function. The operational quality of the light facilities will be efficiently improved with some practical advantages such as reduction of required facility, manpower and time in managing the lights and control boxes tv using the popular PDA.

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A Bright and Wide Color Gamut Reflective Full-color LCD using Diffused Light Control Technology

  • Ishinabe, Takahiro;Uchida, Tatsuo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1377-1380
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    • 2008
  • A development of low power display is an important problem from a point of reduction in worldwide energy consumption. In this research, we aimed to achieve a high quality and low power paper-like reflective full-color display and investigated the design rules for the light diffusing film, LC-cell structure, front lighting systems based on the diffused light control technology. As a result, we successfully obtained the high quality reflective liquid crystal display with a high reflectivity, a wide color gamut and a high motion picture quality.

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A Current-Mode DC-DC Buck Converter with PFM to Improve the Light-Load Efficiency (Light-load에서 고효율을 가지는 PFM 전류모드 DC-DC Buck 변환기)

  • Ahn, Young-Kook;Nam, Hyun-Seok;Roh, Jeong-Jin
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.601-602
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    • 2008
  • This paper presents pulse-frequency modulation(PFM) to improve the light-load efficiency. The proposed circuit is designed by using the device parameter of standard $0.13{\mu}m$ CMOS process. The performance of proposed circuit is evaluated by HSPICE simulation Measured efficiency in a light-load is measured 78-90 % for 0.1 to 100mA output current.

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