• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.10
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• pp.1-8
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• 2013

Wireless Visible Light Communication is the technology that enables communication using LED illumination Infrastructure instead of existing illumination such as incandescent lamp or fluorescent light. Because VLC uses light for communication, it has no problem of frequency permission and is harmless to human body. It is also possible to check the communication through eye. So VLC can be used as a supplement to the Radio Frequency communication, Infrared in indoor environment. So far, researchers on the LED Visible light communication have focused on the increasing transmission speed, transmission distance, modulation method. However, there is few research of main factors that influence on system performance. System performance has been mainly predicted through simulation. In this paper, I recognized that these factors such as outside light noise, obstacle, LED panel position or emitted angle have a great impact on wireless communication system. So I experimented VLC system by changing distance and position to discover location suitable for BER regulation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.10
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• pp.610-617
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• 2004

This paper presents a novel high frequency generating circuit integrated chopper-inverter using ZVS with high power-factor. The proposed topology is integrated half-bridge boost rectifier as power factor corrector(PFC) and half-bridge high frequency resonant inverter into a single-stage. The input stage of the half-bridge boost rectifier works in discontinuous conduction mode(DCM) with constant duty cycle and variable switching frequency. So that a boost converter makes the line current follow naturally the sinusoidal line voltage waveform. Simulation results have demonstrated the feasibility of the proposed high frequency resonant inverter. Characteristics values based on characteristics analysis through circuit analysis is given as basis data in design procedure. Also, experimental results are presented to verify theoretical discussion. This proposed inverter will be able to be practically used as a power supply in various fields as induction heating applications. fluorescent lamp and DC-DC converter etc.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2696-2698
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• 2005

기존 형광램프의 조도 조절이 가능한 조광가변 전자식 안정기의 경우 조광 설정 스위치와 조광가변 전자식 안정기와의 상호 연계 동작을 위해 안정기와 스위치 사이에 전원선 이외에 별도의 통신선로를 포설해야 하고, 이에 따른 비용 증가와 시공상의 어려움이 있다. 이런 단점을 극복하기 위한 방법 중의 하나로 전력선 통신을 사용할 경우 기축 건물에도 보다 쉽게 시공할 수 있으며, 별도의 통신 선로 포설에 의한 비용 부담도 줄일 수 있다. 본 연구에서는 (주)젤라인에서 개발된 ARM9 코어를 내장한 전력선 통신 칩(XPLC30)을 이용하여 기존 조광가변 전자식 안정기에 전력선 통신 기능을 추가하여 조광설정 스위치와 안정기간의 통신이 전력선을 통하여 이루어질 수 있도록 하고, XPLC30의 여분의 프로세싱 능력을 활용하여 기존의 조광가변 전자식 안정기에서 사용하던 조광 제어 칩의 여러 기능을 XPLC30 칩이 대신 할 수 있도록 하는 전력선 기반의 조광 체어 칩의 구현에 대한 연구를 하고자 한다.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.2 s.31
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• pp.37-41
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• 2004

Parallel combination of cold chathode fluorescent lamps (CCFL) are widely used as the light sources of LCD TV backlight. Brightness uniformity is safisfied by using one transformer per one CCFL. Instead of using one transformer per oneCCFL, one transformer is used to drive 8 CCFLs by using differential driving method. A differential driving inverter with two transformers is developed to drive 16 CCFLs of 26' backlight for LCD TV. The brightness uniformity of $88\%$ was obtained by driving 26' backlight with the developed differential driving inverter successfully.

• The Transactions of the Korean Institute of Power Electronics
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• v.5 no.5
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• pp.501-507
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• 2000

A nobel low-cost, simple and unity-power-factor electronic ballast is presented. The proposed electronic ballast employs a bypassing capacitor- and load networks composed of ballast capacitors and small charge pump capacitors as power factor correction circuit combined with the secondary winding of the transformer in the self-excited current-fed push-pull resonant inverter(CF-PPRI), resulting in cost-effectiveness and higher efficiency. By analyzing the princip1es of power factor correction mathematically, optimum design guidelines are presented. Since the lamps are used in power factor correction stage, the input power is automatically adjusted according to the number of the lamps.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1123-1126
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• 2003

In this paper, the emission properties of electrodeless fluorescent lamp were discussed using the inductively coupled plasma. To transmit the electromagnetic energy into the chamber, a RF power of 13.56MHz was applied to the antenna and considering the Ar gas pressure and the RF electric power change, the emission spectrum, Ar- I line, luminance were investigated. At this time the input parameter for ICP RF plama, Ar gas pressure and RF power were applied in the range of $10{\sim}60m$ Torr, $10{\sim}300W$ respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.11
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• pp.729-735
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• 2016

It is highly important issue to use an energy efficiently for sustainable prosperity of mankind. From this point of view, using LED lighting can be a good alternative because it has a lot of advantages such as high efficiency, long life time and eco-friendly manufacturing process. That is the reason why using LED lighting has been encouraged worldwide. However, in situations that LED lighting is replacing traditional lighting quickly, the problem of the flicker of LED lighting has emerged as an important issue. Therefore, in foreign countries like US or Japan in order to ensure the reliability of LED lighting, study for flickering effects of the human body and test methods are have been actively conducted. But related research in domestic situation is an insufficient condition. In this study, a flicker characteristic was measured conventional lamps such as incandescent lamps or fluorescent lamp and 81 items of LED lightings which are distributed in domestic markets.

• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.59-63
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• 1998

The light sensitivity and angular dependence of the $Mg_2SiO_4$:Tb(MSO-5) TLD which affect the accuracy of the radiation dose measurement are investigated. Light-induced thermoluminescence of MSO-S TLD under the 200 lux fluorescent and the incandescent lamp for 8 hours are corresponding to 11 and 3 mR exposure, respectively. TL intensity ratio of the incident angle of ${\pm}80^{\circ}$ to normal incidence for MSO-S and badge type MSO-L are about 0.8 and 0.15, respectively.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.290-297
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• 2010

The effect of supplemental light such as metal, Na and fluorescent lamp on the growth and productivity of tomato for 5 hours a day The growth rate of tomatoes under artificial light were increased 6~10% rather than the growth rate of tomatoes under no light treatment. Also the quantity and productivity of tomatoes under artificial light were increased rather than the quantity and productivity of tomatoes under no light treatment. Increasing profitability per 10a under artificial light were 9.4~28.2 million won.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.40-45
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• 1978

We have selected 36 schools of a total of night high schools for boys and girls in seoul and measured intensity of illumination of the classroom, The corridors and the stairs that students study and live, with priority given to an illumination, a primary factor of environmental sanitation of school following is the result. 1. The maximum average intensity of illumination of the classroom is 93.2 Lux, and the minimum average intensity of illumination 39.5 Lux. Mean$\pm$S, is 59.03$\pm$22.8 Lux 2. The maximum average intensity of illumination of the corridor is 39.2 Lux, and the minimum average intensity of illumination 11.1 Lux. 3. The maximum average intensity of illumination of the stair is 11.58 Lux, and the minimum average intensity, of illumination 4.92 Lux, mean$\pm$S.D is 7.88$\pm$10.0Lux. 4. Schools with tile illumination facilities more than 50 Lux are 63.8% and less than 50 Lux are 36.2%. 5. Schools with 9-11 facilities of a source of light per classroom by a fluorescent lamp are the most as 30.50%. 6. As for the corridor, schools with the illumination equipment less than 10 Lux are 27.8%, are more than 10 Lux 72.2% 7. As for the stairs schools with the illumination equipment less than 10 Lux are 77.8%, and more than 10 Lux 10 Lux 22.2%.