• 조명전기설비학회논문지
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• 제25권5호
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• pp.7-14
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• 2011

Currently high power Light Emitting Diode (LED) is in the limelight due to its characteristics of long durability, low maintenance costs, and high efficiency. Furthermore, it does not emit pollutants or poisonous gases and is a light source not using mercury, so it holds a high status in eco-friendly terms as well. In this paper, we studied a two-stage LED power drive circuit that can compensate only voltage regulation through LED output current, in order to improve efficiency of LED drive with constant current control in accordance with changes in temperature. The proposed LED drive has an advantage of reducing LED drive's voltage losses by controlling only voltage change of input power, compared with an existing circuit which controls input voltage. The suggested non-insulation compensating circuit for voltage change was verified to have improved efficiency relative to a LED drive using existing DC/DC converter.

• 기술사
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• 제42권5호
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• pp.46-49
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• 2009

Many companies are looking for going into the LED Industry as LED has the brightest prospects in the future compare to any other industries. But many companies are lack of comprehension of market for successful entry decision. It is highly recommended to setup the effective strategy by categorizing the LED application markets and selecting the target market. In this paper LED Lighting industry is mainly explained among the many LED markets.

• 광산업정보
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• 통권32호
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• pp.18-29
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• 2006

빛고을 광주 첨단 산업단지에 LED신호/조명시스템시범단지가 조성된다. 한국광산업진흥회(회장 이기태)는 지난 2004년부터 오는 2008년까지 5년간 82억원을 투입해 광산업 2단계 육성사업의 일환으로 LED신호/조명시스템시범구축사업을 추진한다. 이 사업은 LED관련 제품의 테스트 베드와 홍보기회를 제공해 관련 산업의 신규 수요를 창출하고 광산업제품의 우수성을 홍보하기 위해 실시된다. 한국광산업진흥회는 이 사업을 통해 LED관련 신기술 및 신제품 개발의 동기부여, LED 관련 시젶품 홍보를 위한 데스트베드 제공, LED관련 제품 수요창출을 통한 기업 매출증대 및 지역경제 활성화에 크게 기여할 계획이다.

• 한국전기전자재료학회논문지
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• 제28권7호
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• pp.473-479
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• 2015

Hybrid supercapacitors with high power density and long cycle life are widely used for emergency power source of LED emergency luminaires. In this paper, we designed and fabricated a hybrid capacitor cell and a module for the LED emergency luminaires. Using hybrid supercapacitor cells (1,000 F, 2.8 V), we designed a module in a 10-year warranty considering aging and ESR. Considering the ESR and efficiency has been designed to module with 1,000 F 5.6 V design results in 2 series and 2 parallel combination. Module was used to confirm that the operation 77.5 minutes at room temperature, discharge LED emergency luminaires with 2 W. As a LED emergency luminaires of emergency power supply that we can support more than 10 years of life was confirmed the applicability of hybrid supercapacitor.

• 한국전기전자재료학회논문지
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• 제33권5호
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• pp.418-426
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• 2020

This study tested the electrical, structural, and thermal safety of LED lighting products, available on the market. Five recessed LED systems, 20 W each, and five fixed LED systems, 25 W each, were selected. Dielectric strength tests, live part electric shock protection tests, and thermal tests were conducted on the LEDs. These were key tests for user safety, according to the specification of the safety criteria for electric products, KC 60598-1, South Korea. In addition, the wiring temperature of UL1007, 60227 IEC 08, and UTP cables, was measured. The results of the study gave an in-depth examination of the safety of LED lighting systems for users.

• Journal of Biosystems Engineering
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• 제37권5호
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• pp.314-318
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• 2012

Purpose: This study was conducted to develop a measurement system for determining photosynthetic photon flux (PPF) distribution and illumination efficiency of LED lamps. Methods: The system was composed of a linear moving sensor part (LMSP), a rotating part to turn the LMSP, a body assembly to support the rotating part, and a motor controller. The average PPF of the LED lamp with natural cooling and water cooling was evaluated using the measurement system. Results: The PPF of LED lamp with water cooling was 3.1-31.7% greater than that with natural cooling. Based on the measured value, PPF on the horizontal surface was predicted. Illumination efficiency of the LED lamp was slightly increased with water cooling by 3.4%, compared with natural cooling. A simulation program using MATLAB was developed to analyze the effects of the vertical distance from lighting sources to growing bed, lamp spacing, and number of LED lamps, on the PPF distribution on the horizontal surface. The uniformity of the PPF distribution of the LED lamps was fairly improved with 15 cm spacing, as compared to the 5 cm spacing. By simulation, PPF of $217.0{\pm}27.9{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was obtained at the vertical distance of 40 cm from six LED lamps with 12 cm spacing. This simulated PPF was compared to the measured one of $225.9{\pm}25.6{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. After continuous lighting of 346 days, the relative PPF of LED lamps with water cooling and natural cooling was decreased by 6.6% and 22.8%, respectively. Conclusions: From these results, it was concluded that the measurement system developed in this study was useful for determining PPF and illumination efficiency of artificial lighting sources including LED lamp.

• Journal of Advanced Marine Engineering and Technology
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• 제34권4호
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• pp.515-521
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• 2010

본 논문에서는 에너지 절감형 발광다이오드 집어등의 개발과 적용에 대하여 기술하였다. 오징어, 다랑어, 고등어, 정어리 그리고 갈치와 같은 대부분의 생선은 주광성이며, 집어등은 이러한 어류들의 광반응 특성을 이용하여 어업 효율을 증대시킨다. 현재는 집어등으로 소비전력이 1.5 kW이고 인체에 유해한 자외선을 방출하는 메탈 할라이드 램프(MHL)가 대부분 사용되고 있다. LED 집어등의 개발을 위해, 광 파장에 따른 해수투과와 오징어의 광반응 특성을 연구하였다. 실험에서는 상기 두 가지 특성이 모두 470 nm 전후의 청색에서 나타났다. 결과에 근거하여, 1.5 kW MHL의 약 1/9의 소비전력인 160 W급 청색 LED 집어등을 제작하였다. 에너지 절감효과로 LED 집어등은 1.5 kW 80개의 MHL을 설치한 22톤 어선의 경우, 시간당 128 kWh의 전력소모를 줄일 수 있으며, 이는 이산화탄소 86 kg에 해당한다. 시제작 LED 집어등은 2척의 어선에서 실증 조업 중에 있다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.313-313
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• 2012

In recent years there have been many studies of InGaN/GaN based light emitting diodes (LEDs) in order to progress the performance of luminescence. Many previous literatures showed the performance of LEDs by changing the LED structures and substrates. However, the studies carried out by the researchers so far were very complicated and sometimes difficult to apply in practice. Therefore, we propose one simple method of changing the thickness and the numbers of multiple quantum wells (MQWs) in order to optimize their effects. In our research, we investigated electrical and optical properties by changing the well thickness and the number of quantum well (QW) pair in LED structures by growing the structure -inch Si (111) wafer. We defined the samples from LED_1 to LED_3 according to MQW structure. Samples LED_1, LED_2 and LED_3 consist of 5-pair InGaN/GaN (3.5 nm/ 4.5 nm), 5-pair InGaN/GaN (3 nm/4.5 nm) and 7-pair InGaN/GaN (3.5 nm/4.5 nm), respectively. We characterized electrical and optical properties by using electroluminescence (EL) measurement. Also, Efficiency droop was analyzed by calculating external quantum efficiency (EQE) with varying injection current. The EL spectra of three samples show different emission wavelength peaks, FWHM and the blueshift of wavelength caused by screening the internal electric field because of the effect of different MQW structure. The results of optical properties show that the LED_2 sample reduce the internal electric field in QW than LED_1 from EL spectra. the increase in the number of QW pairs reduces the strain and increase the In composition in MQW. And, the points of efficiency droop's peak show different trend from LED_1 to LED_3. It is related with the carrier density in active region. Thus, from the results of experiments, we are able to achieve high performance LEDs and a reduction of efficiency droop and emission wavelength blueshift by optimizing MQWs structure.

• 한국버섯학회지
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• 제12권4호
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• pp.270-274
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• 2014

표고 톱밥배지 재배시 녹색LED 광량에 따른 생육특성분석 결과 $5umol{\cdot}m^{-2}{\cdot}s^{-1}$에서 3주기 기준 배지당 자실체의 수량은 239 g으로 형광등 202 g 대비 18% 증수효과가 있었으며, 자실체 폴리페놀 함량은 형광등 107 ppm에 대비 78.4 ppm으로 27% 정도 낮았지만 에르고스테롤 함량은 형광등 145 ppm 대비 307 ppm으로 2.1배 높은 함량을 보였다. 전력소모량은 형광등 대비 15.9%의 에너지 절감율을 보였으며, 전등의 에너지 효율이 77.5%로 가장 컸다.

• 한국버섯학회지
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• 제15권4호
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• pp.264-268
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• 2017

하이테크 산업은 이른바 스마트 농업의 융합에 장벽을 극복하기 위해 농업의 경관을 바꾸고있다. 정밀 농업의 핵심인 온도, 습도, 위치 정보 및 실시간 요약 정보 등의 중요한 ICT제어기술을 적용하여 버섯재배온도, 습도, 조명, 이산화탄소 등의 제어가 가능한 컨테이너형 버섯재배 시스템을 설계제작하였으며, 버섯 재배에 활용가능성을 표고버섯을 대상으로 시험을 수행하였다. 표고버섯의 초발이소요일수는 청색 LED광에서 5~6일, 적색 LED광, 청색-적색-흰색 혼합 LED광, 형광등에서 6~7일로 유사하였고 생체중은 청색 LED광에서 39.82 g으로 타처리구에 비해 우수하였다.