• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.9-10
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• 2007

In this paper, we investigated the effect of solar cell breakage on maximum output power of PV module. The test result using artificial light source didn't give any change in output power in case of crack near electrical ribbon. Also, there was a reduction in output power in case of increasing of crack area far from electrical ribbon. But, this experiment is under artificial light source test method. So, when such a PV module is outdoor for a long time, there would be problems on electrical output power and durability because of thermal aging phenomenon of solar cell breakage.

• 한국환경농학회지
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• 제41권4호
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• pp.245-251
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• 2022

BACKGROUND: Selection an suitable light source is essential in the year-round production of horticultural crops in closed production systems such as plant factory with controlled environments. This study was investigated to confirm the effects of artificial light sources on growth of cherry tomato'CF Jelly'(Lycopersicon esculentum var.) under high-pressure sodium lamps (HPS), metal-halide lamps (MH), and LEDs. METHODS AND RESULTS: Light intensity of the light sources was controlled at 220±30 µmol/m²/s with 12 hrs of photoperiod for a day. Flower development was significantly faster in HPS and MH treatments compared to the LEDs. There was no significant difference between the leaf number and leaf shape under the HPS and MH treatments. Reproductive growth of cherry tomato was significantly promoted by the LEDs treatment of blue plus red lights. Fruit yield per plant also increased under the LEDs compared to the others. CONCLUSION(S): Growth, flowering, and fruit setting of the cherry tomato were accomplished by the artificial lights under plant factory conditions. The HPS treatment showed negative effect on fruit quality in terms of blossom-end rot incidence compared to the LEDs or MH treatment. Effect of the LEDs on promotion of fruit weight and yield was also proved. Additional research should be carried out for improving sugar metabolism or decreasing disease in the fruits under plant factory system using only artificial lights.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2001년도 동계 학술대회 논문집
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• pp.160-166
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• 2001

• Journal of Biosystems Engineering
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• 제23권6호
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• pp.591-598
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• 1998

Light intensity and spectral characteristics of different types of fluorescent lamps were tested to investigate their possibility as the artificial lighting sources for the close illumination applied in the transplant production factory. Photosynthetic photon flux densitiy(PPF), illuminance and irradiance for all lamps decreased logarithmically with an increase of the vertical distance from the lighting source. The fluorescent lamp specially designed plant growth (PG lamp) showed a maximum spectral irradiance at the wavelength of 660nm. However, it showed lower irradiance than that of a standard fluorescent lamp at the range of wavelength between 500 and 600nm. On the other hand, PG lamp showed higher PPF and lower illuminance than those of the standard fluorescent lamp. The maximum peak of spectral characteristics for both of the single and twin three-bind fluorescent lamps was shorn at the wavelength of 545m and the next peaks were shown at the wavelength of 610nm and 435nm, respectively. Since the red fluorescent lamp has a narrower peak at the wavelength of 660nm, it may be useful for the supplementary red lighting. For three of standard, single three-band and twin three-band fluorescent lamps, the values of conversion factor for converting illuminance to PPF fell within the narrow range from 76 to 791x/$\mu$molㆍm$^{-2}$ ㆍs$^{-l}$ . However, for PG lamp, it was 29.71x/$\mu$molㆍm$^{-2}$ ㆍs$^{-1}$. Also, the values of conversion factor for converting PPF to irradiance of fluorescent lamp used in this study ranged between 4.85 and 5.34$\mu$molㆍm$^{-2}$ ㆍs$^{-1}$/Wㆍm$^{-2}$ .

• 한국위성정보통신학회논문지
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• 제9권3호
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• pp.74-79
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• 2014

조명은 현재 인류에서는 없어서는 안 될 유효사용 기술 중 하나이다. 이러한 조명은 태양광에 의한 주광조명(晝光照明)과 인공광원을 통해 생성되는 인공조명(人孔照明)이 있으며, 본 논문에서는 전기에너지를 통해 생성되어지는 인공조명의 제어기술과 효율적인 운영방안에 대한 연구를 진행하였다. 일차적으로 인체를 감지하기 위하여 Doppler Sensor를 사용하여 인체를 감지하고 이에 대한 감지신호를 기반으로 하여 LED조명의 연속디밍 컨트롤 하여 효율적인 에너지 관리를 하기 위한 기술이다. 이와 같이 본 논문에서는 전기적인 에너지원을 기초로 하여 LED 조명에 대한 연속 디밍 기법과 도플러 및 적외선센서 융합 기법을 제안하고자 한다.

• 한국통신학회논문지
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• 제36권11B호
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• pp.1394-1402
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• 2011

본 논문은 포물 반사경 방식 및 프레넬 렌즈 방식을 이용한 태양광 집광장치 및 이의 응용에 관한 것이다. 본 시스템은 대구경 반사경과 더불어 2차 광학계를 도입하여 광섬유로 입사되는 빛의 입사각을 광섬유의 개구수보다 작게 함으로써 집광효율을 극대화하였다. 또한 광섬유 단면에 입사하는 빛의 에너지 밀도를 낮게 하기 위해 광섬유 다발 직경 크기와 동일한 평행광이 광섬유로 입사되게 함으로써 반사경을 사용한 집광 시 문제가 되는 열발생 문제를 별도의 냉각장치 없이 근원적으로 차단하였다. 최근 각광받고 있는 식물공장에 주로 쓰이는 LED와 같은 인공광원 대신 본 연구에서 개발한 태양광 집광장치를 식물공장에 적용하여 인공조명과 태양광의 혼합조명장치를 통해 식물을 재배하였다. 그 결과 낮 시간대에 인공조명에 소요되는 전기에너지를 대폭 절감할 수 있었다. 혼합조명장치에서는 조도센서를 활용하여 항상 일정량의 빛이 식물에 제공되도록 LED등의 밝기를 조절하였다. 하루 10시간 기준으로 100형 규모의 식물공장에 태양광 채광시스템을 적용할 경우 한 달에 약 28,080KWh의 에너지 절감효과가 있다.

• 한국실내디자인학회논문집
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• 제23권2호
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• pp.3-11
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• 2014

Light has been considered as one of the most important elements in architectural design. Light provides occupants in buildings a lot of architectural experiences by interrelating the space, shape and other design elements. Especially, natural light is the valuable source to create the better indoor space compared to artificial light. It is a sustainable energy source and offers a more natural environment. It also enables occupants to perceive the form and depth of space. In general. many of architects including Henri Ciriani have tried to design buildings with natural light expecting optimum indoor environment. Therefore, this paper tried to examine the works of Henri Ciriani and analyze how to control the light in his works. For this purpose, two museums designed by Henri Ciriani-Arles Museum of Archaeology and Great War Historical Museum in Peronne - were selected to analyze how Henri Ciriani used light in his design phase and applied it to his museum works. According to the results of the study, it has been proved that Henri Ciriani tried to realize a space continuum through the spatial expansion, openness and closeness by natural light and incorporate the architectural form, interior space and exhibition circulation with natural light in order to create innovative exhibition space in museum buildings.

• 복식문화연구
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• 제15권2호
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• pp.214-220
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• 2007

The purpose of this study is to derive the use of the luminous source corresponding to the intention and contribute to product display by visually evaluating the relations between luminous source and colors, analyzing and reviewing the subjective perceptions depending on the luminous source, and clarifying the colors of artificial luminous source that look close to natural lights by each color. Hence, the researcher objectified the subjective evaluation for which they used sensory evaluation method with four colors of luminous sources(natural colors, 2800K, 4200K, and 6500K) and five colors of textiles(purple, blue, green, yellow, and red) by quantifying the evaluation. As a result, we could obtain the conclusion as follows. As for the temperature of textile colors under artificial luminous sources that appeared most close to the colors of textiles under natural luminous sources, 6500K was most frequent, and the temperature of the luminous sources that appeared most different was 2800K. However, as there were also 4200K colors that looked most close to the textile colors under natural light source, it was observed that the temperature differs depending on the textile colors. In addition, less glossy textiles exhibited more visual changes by luminous source colors than comparatively more glossy textiles, and it was observed that the most influenced color was purple, as purple has shown the largest difference among colors.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.632-638
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• 2000

This paper represents the characteristics of evapotranspiration rate (EVTR) and graft-taking of watermelon grafted seedlings in a graft-taking enhancement system using fluorescent lamps as artificial lighting source. Four air temperature levels of 23, 25, 27 and 29C, three humidity levels of 85, 90 and 95%R.H. and two photosynthetic photon flux (PPF) levels of 30 and 50 ${\mu}$mol m$\^$-2/ S$\^$-1/ were provided to investigate the effects of air temperature, relative humidity and light intensity on EVTR and graft-taking of grafted seedlings. EVTR of grafted seedlings increased with increasing air temperature and the passage of time after grafting. Also EVTR increased with decreasing relative humidity. As relative humidity decreased and air temperature increased, vapor pressure deficit increased and thus EVTR increased. It is required to maintain a low level vapor pressure deficit for suppressing EVTR of grafted seedlings during first 1-2 days after grafting. Therefore, less EVTR at initial stage after grafting would be adequate for smooth joining of the scion and rootstock.

• 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.