• 한국전기전자재료학회논문지
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• 제28권1호
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• pp.57-63
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• 2015

Recently, LED is widely used in the kinds of display devices or lighting. In this paper, we fabricated LED chamber light for naval vessels to replace to conventional chamber light using incandescent lamp. The LED package of chamber light was designed with luminous intensity of 5.5 cd, color temperature of $6,000{\pm}500K$, forward voltage of 3~3.2 V and input current of 60 mA. A LED module was composed of 36 LED packages and metal PCB. The VF and luminous intensity of LED package were getting down when temperature increased. The temperature of LED chamber light was measured by changing the number of LED package and applied current for one hour when an electric current flow. The heat transfer capability have been improved by using metal PCB. The power consumption of LED chamber light reduced by 86% compared to the conventional chamber light using incandescent lamp.

• 산업기술연구
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• 제31권A호
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• pp.95-101
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• 2011

According to recent technological developments in high-power LEDs, the stage lighting is one of most important areas to apply power LED system. Moving light for color rendering of stage uses the RGBW(red, green, blue, white) color mixing method. LED moving light system needs to have a wide range of dimming control as enough to operate at very low power. Also LED dimming system should not be induced color-shift and flicker in camera. This paper is experimentally verified the LED Moving Light driving circuit of 200Watt level designed to satisfy the above characteristics which applied the DC current-controlled and PWM mixed dimming method.

• Journal of information and communication convergence engineering
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• 제11권4호
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• pp.247-252
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• 2013

An intelligent light emitting diode (LED) dimming system is designed and implemented for energy-saving lighting systems. An LED light bulb is powered by an LED driver controlled by a microcontroller using pulse width modulation (PWM) signals. By changing the duty cycle of the PWM signals, the LED driver generates a driving current of up to 1,000 mA. The current consumption by the LED light bulb exhibits a very linear characteristic that indicates that the level of LED dimming can be finely tuned. Multiple sensors-lighting intensity and ultrasonic range sensors-are combined with the LED dimming system to realize an automatically controllable LED lighting system. The light intensity sensor is capable of sensing ambient light. The ultrasonic range sensor can detect objects from 0.15 to 5.6 m at a resolution of 0.0254 m. The collected information by the light intensity and ultrasonic range sensors is processed by the microcontroller that in turn automatically controls the brightness of the LED light bulb. The algorithm of the software for the LED dimming system is also described.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.15-16
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• 2012

LED(Light Emitting Diode)는 기존 광원보다 고효율, 저전력, 장수명으로 인해 일반 조명들을 모두 대체될 것으로 전망되며, 또한 기본적으로 반도체 소자이기 때문에 전기에서 빛으로 바꾸는 속도가 매우 빠르며, 이와 같은 특성을 이용하여 고속 ON-OFF 스위칭을 통한 통신 변조를 수행 할 수 있다. 최근에는 이러한 특징을 이용한 가시광 통신(VLC: Visible Light Communication)기술이 주목받고 있으며, 많은 연구가 진행 되고 있다. 본 논문에서는 LED와 가시광 통신을 융합하여 송신부에는 LED 발광소자와 수신부에는 적외선센서를 사용하여, 미디어 신호 전송을 구현하였다. 미디어 전송 속도를 개선하기위해 가시광 통신에 적용되는 기존 가시광 통신용 LED 드라이버의 전력 변환 효율 및 발열 문제를 개선하고자 통신 시스템의 효율 증대를 위해 새로운 방식의 LED 드라이버를 연구하고자 한다.

• 한국산학기술학회논문지
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• 제13권10호
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• pp.4740-4744
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• 2012

본 논문은 Zigbee를 이용한 LED 조명 제어 모듈을 구성 하고자 하였다. LED 조명 제어 모듈은 주변 밝기의 변화에 따라 LED 조명의 밝기를 제어하도록 하였으며, 논문에서 구성된 제어 모듈은 8bit 마이크로 컨트롤러를 사용하여 LED 디밍 및 무선 조도 측정이 가능하도록 구성하였다. 제안된 방법을 적용시 소비전력량 3.4~0.4W의 변화로 평균 48%까지 개선될 수 있다. 측정된 주변 조도값을 ADC 변환하여 설정된 PWM 파형으로 출력하게된다. 이렇게 출력된 파형에 따라 LED Driver에서 출력되는 전류값 변화에 따라 LED 조명의 밝기를 제어하게 된다. 또한 근거리 무선통신이 가능한 Zigbee를 이용하여 무선을 이용한 조도 측정값을 전송가능 하도록 구성하였다.

• 조명전기설비학회논문지
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• 제29권5호
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• pp.26-33
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• 2015

Secondary optical system designed for LED bulb which emits light in all directions was simulated with Energy Star standards. Components of the optical system were LED light source, the cover of the LED bulb and reflector which is to confirm the diffuser plate and LightTools software was used to design the illumination optics. The main points of the secondary optical system design are the location of the LED light source, the shape of the LED bulb cover, the location of the reflection plate, and the scattering properties of the diffusing plate. Mechanism of the LED bulb is that the light emitted from the light source move on to the backward after reflected by the coated light cover from the inside and then the reflected light is scattered by the diffuser plate. The LED bulb was designed to satisfy the standard light distribution and color specifications of the Energy Star(IES LM-79-08).

• 수산해양기술연구
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• 제53권3호
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• pp.240-245
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• 2017

In order to study for the growth of fish in the aquaculture industry, the behavior analysis of rock bream (Oplegnathus fasciatus) depending on the temperature and LED lights was conducted. In this study, water temperatures from 10 to 30 degrees were used. One red light (wave length: 622 nm; light power: 811 mW) and one green light (wave length: 518 nm; light power: 648 mW) were used. Behavior of the rock bream was analyzed at an average moving distance for one minutes (AMD) and a rate of movement. The mean AMD were respectively 5.3 m, 7.3 m and 3.0 m in the red LED light, green LED light and control condition. The mean rates of movement were 77%, 88% and 61% respectively in the red LED light, green LED light and control condition. The mean AMD during 24 hours were 3.1 m, 3.1 m and 3.3 m respectively in the red LED light, green LED light and control condition.

• International Journal of Aerospace System Engineering
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• 제1권1호
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• pp.44-47
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• 2014

This study proposes a development for the nano silver adhesive, which is applicable to high efficiency LED(light-emitting diode) light. The important issue of LED light is heat exhaust from LED. Generally, the middle area of LED light is increased up to 380K. Therefore, the bottleneck between LED chip and heat sink are caused by high temperature. In this work, the adhesive material between LED Chip and heat sink was newly developed for improvement of bottleneck. The nano silver was adopted to solve heat problem of chip on board package for LED light. In order to evaluate the performance of the nano silver adhesive, the thermal analysis was performed. Moreover both adhesive performance and heat exhaust were verified through the prototype test. From the experimental test results, it is found that the developed nano silver adhesive has the high performance.

• 한국위성정보통신학회논문지
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• 제8권2호
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• pp.44-49
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• 2013

LED 통신은 LED(Light Emitting Diode)에서 나오는 가시광선을 이용해 정보를 전송하는 무선통신기술로 RF(Radio Frequency) 통신의 문제점인 주파수 할당, 인체 내 유해성, 보안의 취약성, 전자기기 간 간섭 등을 극복할 수 있는 기술이다. LED를 이용하여 조명과 통신을 동시에 사용할 수 있는 융합 기술로 유비쿼터스 환경에 적합하다. 본 논문에서는 LED, PD(Photodiode) 및 MCU(Micro Controller Unit)를 이용한 LED 통신 시스템의 데이터 전송 알고리즘을 개발하였고 구현하는 과정을 소개한다.

• 전기학회논문지P
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• 제58권2호
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• pp.142-147
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• 2009

Conventional HP(high pressure) sodium or Metal-halide lamps have a life span of around one year requiring at least annual replacement and maintenance. High Power LED lights require no regular maintenance further increasing savings on replacement bulbs, access equipment and labour costs. New installations benefit from a substantial reduction in the cost of expensive heavy duty cable required for sodium lighting. Especially, LED light can achieve variable color temperature, high functional performance in the field of street light. There are two main method to achieve variable color temperature function of the street light. one method is using RGB multi-chip LED, the other is using Orange-White LED method. In this paper, it was compare RGB Multi-chip LED with white-orange LED for there characteristics performance.