• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.118.3-118
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• 2001

CLED (Contact Light Emitting Device) has three layers consisting of a transparent electrode, a light emitting layer and a substrate. When the substrate of the CLED comes in contact with a fingerprint under AC input voltage, it makes an electric field between the fingerprint and the device. Due to the electric field, the light is emitted along the ridgeline of the fingerprint. The intensity along the ridge on the surface of the CLED increase in proportion to the electric field. To achieve uniform performance of fingerprint verification devices, inspection system of CLED for quality control were required. In this research, we proposed the factors for quality controls such as dimensions of the CLED, uniformity ...

• Environmental Engineering Research
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• 제13권4호
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• pp.197-202
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• 2008

This study evaluated the photocatalytic oxidation of BPA using the RPOD reactor under various conditions. This study found that the RPOD was effective for BPA degradation. It could reduce 1 mg/L of BPA by half within 5 min under the optimum conditions. According to the study results, $TiO_2$ coating was important for the BPA oxidation. As the coating thickness increased, the removal efficiency improved. The light source, the light intensity and the drum rotating speed were important for the oxidation. The UV light was more effective for the BPA degradation than the visible light. The removal efficiency improved with increasing intensity. As the drum speed increased, the removal efficiency improved. The maximum speed was 240 rpm in this study. Addition of air and nitrogen was not beneficial for the BPA degradation in this study probably due to enough oxygen in the water.

• 한국통신학회논문지
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• 제36권11B호
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• pp.1383-1388
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• 2011

세계적으로 온실가스 감축 정책, 전기전자제품 유해물질 사용제한 지침(RoHS: Restriction of Hazardous Substances) 등 환경 규제 제도의 본격 시행으로 전통적인 조명이 친환경 고효율 LED(Light Emitting Diode)로 빠르게 대체되고 있으며, 에너지 효율의 극대화를 위한 효과적인 조명 제어 기술이 요구되고 있다. 본 논문에서는 여러 광원으로 이루어진 LED 조명 광원의 효과적인 제어를 통해 실내의 각 위치에 따라 요구되는 조도를 만족하면서 LED 조명 시스템의 에너지 소비를 개선하는 조명제어 기법을 제안한다. 실내 각 영역별 사용자 유무, 요구조도 수치 등을 반영하여 조명제어 최적화 문제를 구성하고, 이에 관한 해를 도출하여 LED 조명의 개별 광원 광도(luminous intensity)를 효과적으로 조절한다. 이를 통해 제시되는 각 위치별 요구조도를 만족하고, LED 조명 시스템 에너지 소모를 효율적으로 감소시킨다. 모의실험 결과 제안된 방식이 기존 방식 대비 사용자 실내 점유율 증가에 따라 약 40%, 조명과 피조면 사이 높이 변화에 따라 약 24~71%의 소비전력을 절감 효과를 얻음을 보인다.

• 생물환경조절학회지
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• 제13권1호
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• pp.44-50
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• 2004

본시험은 백침계 오이에 있어 착과기 이후의 저광도 조건이 생육 및 수량에 미치는 영향을 검토코자 수행되었다. 광도 처리는 무처리를 비롯하여 100, 200, 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$로 되도록 하였다. 초장과 측지길이는 광도가 낮았던 처리에서 크게 감소되었으나, 저광도 처리간에는 차이를 보이지 않았다. 엽면적과 근중은 100${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$에서 가장 적었으나, 200과 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$처리간에는 차이를 보이지 않았다. 광합성량은 저광도가 될수록 감소되었다. 엽록소 함량과, 근활력 및 일비액 역시 낮은 광도에서 감소하였는데, 200 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$과 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$처리간에는 차이를 보이지 않았다. 잎의 기공 관찰 결과 낮은 광도에서 기공세포의 발달이 억제되었고 기공의 개도도 완전하지 않았으며, 기공크기가 작았으나 기공수는 증가하였다. 낮은 광도 하에서 잎에 황화현상과 유과 형태의 비정상과가 발생되었다. 또한 잎의 Mg와 Ca의 흡수량이 광도가 낮아짐에 따라 저하되었다. 수확과수는 자연광에 비하여 400 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$에서 65%, 200고 100 ${\mu}mol\;{\codt}\;m^{-2}\;{\cdot}\;s^{-1}$에서 각각 80%와 90%의 수량감소를 보였다. 이러한 저광 조건은 처리 후 2주 정도의 초기수량에 크게 영향을 끼쳤으며, 특히 측지 수확과수가 현저히 줄어드는 결과를 보였다.

• 원예과학기술지
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• 제31권1호
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• pp.14-23
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• 2013

This study evaluated the influence of light quality and intensity during healing and acclimatization on the $CO_2$ exchange rate, growth, and morphogenesis of grafted pepper (Capsicum annuum L.) transplants, using a system for the continuous measurement of the $CO_2$ exchange rate. C. annuum L. 'Nokkwang' and 'Tantan' were used as scions and rootstocks, respectively. Before grafting, the transplants were grown for four weeks in a growth chamber with artificial light, where the temperature was set at $25/18^{\circ}C$ (light/dark period) and the light period was 14 hours $d^{-1}$. The grafted pepper transplants were then healed and acclimatized under different light quality conditions using fluorescent lamps (control) and red, blue, and red + blue light-emitting diodes (LEDs). All the transplants were irradiated for 12 hours per day, for six days, at a photosynthetic photon flux (PPF) of 50, 100, or 180 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The higher PPF levels increased the $CO_2$ exchange rate during the healing and acclimatization. A smaller increase in the $CO_2$ exchange rates was observed in the transplants under red LEDs. At a PPF of 180 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, the $CO_2$ exchange rate of the transplants irradiated with red LEDs was lowest and it was 37% lower than those irradiated with fluorescent lamps. The $CO_2$ exchange rates of transplants irradiated with blue LEDs was the highest and 20% higher than those irradiated under fluorescent lamps. The graft take was not affected by the light quality. The grafted pepper transplants irradiated with red LEDs had a lower SPAD value, leaf dry weight, and dry matter content. The transplants irradiated with blue LEDs had longer shoot length and heavier stem fresh weight than those irradiated with the other treatments. Leaves irradiated with the red LED had the smallest leaf area and showed leaf epinasty. In addition, the palisade and spongy cells of the pepper leaves were dysplastic and exhibited hyperplasia. Grafted pepper transplants treated with red + blue LEDs showed similar growth and morphology to those transplants irradiated with fluorescent lamps. These results suggest that high-quality grafted pepper transplants can be obtained by healing and acclimatization under a combination of blue and red lights at a high PPF level.

• 원예과학기술지
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• 제35권1호
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• pp.21-29
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• 2017

This study was conducted to determine the effects of artificial lighting sources on vegetative growth of Phalaenopsis and Doritaenopsis (an intergeneric hybrid of Doritis and Phalaenopsis) orchids. One - month - old plants were cultivated under fluorescent lamps, cool - white light - emitting diodes (LEDs), or warm - white LEDs at 80 and $160{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The blue (400 - 500 nm) : green (500 - 600 nm) : red (600 - 700 nm) : far - red (700 - 800 nm) ratios of the fluorescent lamps, cool-white LEDs, and warm-white LEDs were 1 : 1.3 : 0.8 : 0.1, 1 : 1.3 : 0.6 : 0.1, and 1 : 2.7 : 2.3 : 0.4, respectively. Each light treatment was maintained for 16 weeks in a closed plant-production system maintained at $28^{\circ}C$ with a 12 h photoperiod. The longest leaf span, as well as the leaf length and width of the uppermost mature leaf, were observed in plants treated with warm-white LEDs. Plants grown under fluorescent lamps had longer and wider leaves with a greater leaf span than plants grown under cool-white LEDs, while the maximum quantum efficiency of photosystem II was higher under cool-white LEDs. The vegetative responses affected by different lighting sources were similar at both 80 and $160{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Leaf span and root biomass were increased by the higher light intensity in both cultivars, while the relative chlorophyll content was decreased. These results indicate that relatively high intensity light can promote vegetative growth of young Phalaenopsis plants, and that warm - white LEDs, which contain a high red-light ratio, are a better lighting source for the growth of these plants than the cool-white LEDs or fluorescent lamps. These results could therefore be useful in the selection of artificial lighting to maximize vegetative growth of Phalaenopsis plants in a closed plant - production system.

• 한국전기전자재료학회논문지
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• 제25권9호
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• pp.743-749
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• 2012

In this paper, we designed and fabricated LED navigation lights which can replace the existing ones immediately and overcome disadvantages due to use of conventional lamps. To decide the best arrangement and position of a LED module, optical systems of existing navigation lights were analyzed and refracted routes of rays were simulated. The electrical and optical characteristics of the fabricated LED navigation lights were measured and analyzed with a goniophotometer. To calculate ranges of visibility, the vertical and horizontal luminous intensity distributions were evaluated in accordance with the COLREGs (convention on the international regulation for preventing collisions at Sea). From the results, the proposed LED navigation lights showed suitable characteristics for marine environment with the power consumption reduced by 90% and the maximum luminous intensity increased by 20% compared to the existing navigation lights.

• 한국실내디자인학회논문집
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• 제24권2호
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• pp.189-196
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• 2015

In case of Senior Hospitals, meticulous care is required in both amount and quality of natural lighting because of the semi-long term residence of patients. Natural lighting has a huge impact on the physical and psychological part for the seniors. Likewise, natural lighting is an important factor considered for hospital design because it can also effect hospitalization period of patients. Research subject was K Senior Hospital which was determined as the courtyard-type building made to provide healing environment through natural lighting. Analysis was performed by dividing the space of K Senior Hospital into Central Treatment Department directly used by patients, Outpatient Department(OPD), Ward Department, Common Use Department. Research was carried out in two ways of integration value analysis using SPACE SYNTAX and illumination intensity analysis using ECOTECT. K Senior Hospital intended to actively let in natural light through courtyard and to make patients exposed to natural light when they walk along the circuit corridor built around the courtyard. This environmental consideration affected the utilization rate of Common Use Department and residence time of patients raising the average of Common Use Department on every floor. As a resuit of this study presenting type C and type D, part of four types of illumination intensity, takes higher percentage of almost every spaces compare to the others therefore K Senior Hospital was designed on the assumption of healing environment composition through natural light. The result of this research would be used meaningfully in the space programming phase of Senior Hospitals in the future. Utilization rate can be adjusted using illumination intensity value in the space that integration rate should be planed to be high. The use(purpose) of space and integration rate can be used as a guideline to set illumination intensity of natural.

• 한국통신학회논문지
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• 제36권9B호
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• pp.1108-1116
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• 2011

실내 가시광 무선 통신 기술은 반도체인 LED (Light Emitted Diode)의 발광 특성을 제어하여 디지털 신호를 송신하며, PD (Photo Diode)를 이용하여 광 신호를 송수신하는 차세대 무선 통신 기술이다. 이러한 가시광 무선통신에서 LED는 실내 조명기기로써의 역할 뿐 아니라 우선 통신 시스템의 송신기의 역할도 수행한다. 가시광 무선 통신 시스템은 그 특성 상 통신 영역이 빛의 도달하는 범위로 한정되며, 빛의 광량에 따라 통신 채널 품질이 결정된다. 이에 본 논문에서의 복수의 LED로 구성된 LED 패널의 위치 변화와 LED 발광 각도 변화가 통신 채널 품질에 미치는 영향을 분석하고자 한다. 이를 위한 모의실험을 수행하였고, 그 결과 LED 패널의 위치 및 LED 발광 각도가 조도 및 SNR 변화에 상당한 영향을 끼친다는 사실을 입증하였다.

• 한국균학회지
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• 제36권1호
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• pp.31-35
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• 2008

잎새버섯의 생육환경 중에 광이 자실체 발생 및 생육에 미치는 영향을 구명하기 위하여 광질 3종류(청색광, 녹색광, 백색광), 광량 4수준(200, 500, 8000, 1200 lux)으로 시험한 결과는 다음과 같다. 광질이 자실체 발생 및 생육에 미치는 영향을 조사한 결과 백색광의 발이율이 청색, 적색보다 높고 초발이 소요일수도 3일로 청색광, 녹색광의 5일보다 빠른 것으로 나타났다. 생육일수는 백색광과 청색광이 14일로 녹색광(16일)보다 2일 빠르며, 전체 재배일수 또한 백색광이 52일로 청색광보다 1일, 녹색광보다 4일 단축되었다. 봉지당 수량성에서도 백색광이 242 g 으로 청색광(230 g)과 녹색광(216 g)보다 우수하였다. 백색광의 광량이 지질체 발생 및 생육에 미치는 영향을 조사한 결과 200 lux의 광량에서 발이율이 가장 우수하고, 초발이 소요일수도 4일로 500, 800, 1200 lux의 $7{\sim}8$일보다 $3{\sim}4$일 정도 빠른 것으로 나타났다. 생육일수는 500 lux가 9일로 가장 빨랐으며, 전체 재배일수는 200, 500 lux가 49일로 800, 1200 lux의 51일보다 2일정도 빨라 광량이 증가할수록 재배기간이 다소 길어졌다. 봉지당 수량성은 500 lux가 257 g 으로 가장 우수하였고, 광량이 증가할수록 갓의 크기가 신장되고, 갓 색이 다소 진한 것으로 나타났다.