• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.11
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• pp.9-19
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• 2012

The purpose of this study is to present the direction of LED lighting development to give people a comfortable feeling. For about 2 years, the database of daylighting color has been built by daylighting measurement and analysing hourly, monthly and seasonal change in daylighting colors. Finally, changes of color coordinates were drawn as a graph and it presented as the LED lighting color development indicator through the relationship with Plankian locus. This methodology is expected to contribute to the development fields of the LED lighting color.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.170-173
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• 2007

본 논문에서는 LED광원에서 현재 가장 많이 사용되는 MR과 PAR 타입의 램프를 측정 분석하였다. 최대광도 및 광속의 측정값을 비교 분석하였다. 그러나 MR 16 및 PAR 30의 경우 관련 KS 규격상에 광속에 대한 값을 명기하고 있지 않은데 이것은 램프 뒤쪽에 반사경(다이크로익 미러)이 부착되어 있어 가시광을 일정한 방향으로 집중시키는 투광 개념의 광원이므로 광속 측정의 의미가 필요하지 않아서 인 것으로 생각된다. LED광원의 경우 LED자체의 광 확산이 매우 광범위하고, 반사경의 영향을 적게 받고 있어 사이드 방식으로 측정된 상기의 광속값은 불확도 범위이내에 존재할 것이 확실시되므로 향후 LED관련 규격의 제안시 측정이 요구될 것으로 판단된다.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.168-173
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• 2011

Recently, from a saving energy and environmental lighting sources point of view, using LED lighting have been increased rapidly. The colors of light was applied to the control of dimmers that is composed of red, green, blue, and white(RGBW) to improve the quality of visual environment. Moreover this study has been processed to develop adjustable dynamic LED lighting system on SPD and definitize the various spectral power distribution and color temperature of light through the control of the four dimmers. It is possible to combine up to $432^4$ kinds of light. Measurement of illuminance of range on working surface was as 7~l,831 lux. Application of visual environment for occupants can be expected according to control of lighting performance.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.103-111
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• 2024

We address the problematic issue of blinking in residential LED lighting systems-a phenomenon that has recently become a significant concern due to voltage sags caused by high-power household appliances. To combat this, we developed a two-stage LED converter with integrated anti-blinking circuitry, specifically designed for T5 LED indirect lighting fixtures. The first stage employs a Power Factor Correction (PFC) boost circuit to enhance voltage stability by aligning the voltage and current phases, thereby minimizing power losses. The second stage, a meticulously engineered DC-DC buck converter, ensures stable lighting despite electrical fluctuations. Rigorous testing has confirmed our converter's efficacy in maintaining consistent light output without blinking, thereby substantially improving user comfort and adhering to strict standards for harmonic distortion and electromagnetic compatibility. Our breakthrough provides a robust solution to a pressing issue, marking a significant advancement in LED lighting technology.

• IEMEK Journal of Embedded Systems and Applications
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• v.7 no.2
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• pp.103-111
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• 2012

This paper introduces a novel concept of 'A Green LED Sensitivity Lighting System' which can automatically estimate QoS(quality of service) and emotional requirements of user using smart phone. And it can intelligently control ambient illumination lamp to conserve electric energy and to satisfy human sensitivity. The proposed system has 4 control modes; emotional lighting, smart lighting, green lighting and realistic lighting modes in order to comfort man's emotion, to maximize work efficiency, to save energy consumption and to make the entertainment more fun, respectively. When we choose green lighting mode for indoor office situations, an elaborate simulation shows that the proposed system with home network can reduce the energy by 50% compared to conventional light control system with a fixed time-based switching.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.56-59
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• 2009

In the nineties the invention of the InGaN blue LED has innovated illumination technology. Currently LCD backlighting and more and more general lighting applications are based on white LEDs comprising of inorganic phosphors and blue emitting InGaN chip. Well established phosphor materials are ortho silicates and garnets like yellow emitting YAG:Ce. In our paper we demonstrate that garnet materials also allow for green light emission for both, general lighting and backlighting LED applications.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.21-23
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• 2009

The paper is to evaluate for reliability of LED Modules for Lighting by ALTs(Accelerated Life Tests). The recently, some of KS were established by law of LED Modules for Lighting(KS C 7651, KS C 7652 and KS C 7653), but reliability assessment methods of LED Modules for Lighting were not established. Therefore, the paper aided companies to test methods for accelerated life testing by themselves.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.2999-3004
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• 2010

In comparison with some other light sources, LED has merits such as long lifetime, pollution free, and high energy efficiency. Lately, due to development of LED with high brightness and capacity, LED, which has been applied in display system only, has applied in the field of lighting system. As power LED for lighting system can be burned out by heat problem, the driving current of power LED has to be controlled below the designed value. In this paper, power LED photovoltaic lighting system, which has the current limitting function, has been described. After photovoltaic power is generated from PV panel. it is charged into a battery. And then, after the charged power is converted to DC24[V] through a boost DC-DC converter, it is supplied to power LED at night. It has been validated by designing and testing of 72[W] power LED lighting system, which includes a PV charger, a boost DC-DC converter and a current limiter for driving power LED.

• 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 the Korean Society of Manufacturing Process Engineers
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• v.17 no.1
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• pp.23-33
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• 2018

In the general manual feeder of an LED lighting assembly system, many workers are needed to supply parts to the main conveyor. The automatic feeder for modern automation lighting assembly systems consists of a completely automated feeding system and a magazine system that supplies the parts automatically. A standardized LED panel and diffusion cover is stacked in the cartridge of the magazine system. The structural safety of the automatic feeding system with regard to handling the load from the panels and covers stored in the cartridge should be guaranteed. LED convergency lighting modules are assembled using two LED panels and one diffusion cover in an automatic feeder. In this study, the structural safety and fatigue life of the automatic feeder and magazine were analyzed by considering the load generated in the automatically assembled LED convergency lighting system. In addition, the dynamic behavior of each auto-feeding system and magazine delivery system was visualized, and the working process was evaluated via dynamic simulation using a virtual engineering method. A tack time table for automatic feeding systems was derived by developing a virtual prototype.