• Journal of IKEEE
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• v.25 no.2
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• pp.267-272
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• 2021

Recently, attention has been focused on renewable energy and carbon neutrality to resolve fossil energy depletion and environmental problems. In addition, high-rise urban buildings and an increase in building energy are rapidly increasing. There are many restrictions on installing solar power in urban areas. In addition, as buildings become taller, a lot of low-light environments in which shade is formed occur. Therefore, in this study, we intend to develop a power plant capable of generating electric power in an outdoor low-light environment and indoor lighting environment. The power plant in a low-light environment used a dye-sensitized solar cell. A unit cell and a 20cm×20cm module were manufactured, and the electrical characteristics of the power plant were measured using light sources of LED, halogen lamp, and 3-wavelength lamp. The photoelectric conversion efficiency of the unit cell was 17.2%, 1.28%, 19,2% for each LED, halogen lamp, and 3-wavelength lamp, and the photoelectric conversion efficiency of the 20cm×20cm module was 10.9%, 8.7%, and 11.8%, respectively. In addition, the maximum power value of the module was 13.1mW, 15.7 mW, and 14.2 mW for each light source, respectively, confirming the possibility of power generation in a low-light environment

• 전자공학회논문지 IE
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• v.43 no.3
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• pp.22-27
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• 2006

This paper presents the control system of high-efficiency automotive 35W metal-halide lamp ballast using the new control method and planar transformer. In this paper, the electronic ballast is designed so that digital control method by microcontroller can be applied to the electronic ballast for the lamp requirement and peripheral environment in order that metal-halide lamp, which has the complicated transient features, is to be applied to the automobile even if it has superior features in brightness, color rendering, light efficiency, and lifespan compared to the conventional halogen lamp. Also, the efficiency increase of the ballast is devised by being varied the switching frequency of Flyback Converter following the battery input voltage of the automobile. Being designed for high-frequency switching transformer of converter in planar form, reduction of loss, weight, overall size are realized and efficient power control in the automobile that had the limited energy and the limited space of battery is devised. The results of the proposed system is verified through various experiment results.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.2
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• pp.1-7
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• 2004

This experimental study investigates the wall display of shoes shops among the commercial space to suggest a desirable lighting by focusing on the lighting on the lighting surroundings. The important outcomes of this study are summarized below. The result of the experiment for the wall lighting: For the wall lighting, which needs a diversity, there should be various light source or bigger rate of illuminance between the ambient lighting and the local lighting. There is another possibility that is we can use the lower rate of illuminance with the ambient lighting and the local lighting or higher illuminance generally. The other wall lighting, which need a luminance and a emotional response, will be more effective as they take the lower rate of illuminance with the ambient lighting and the local lighting or higher illuminance generally.

• KSBB Journal
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• v.20 no.6
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• pp.413-417
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• 2005

The purple sulfur phototrophic bacterium, Thiocapsa roseopersicina NCIB 8347 has been studied on hydrogen production and cell growth under different culture conditions, such as light source, light intensity, and growth temperature. T. roseopersicina showed maximum cell growth of 1.38 and 1.42 g-DCW/L under 7.5-10 klux of halogen and fluorescent light, respectively, and produced maximum amount of hydrogen with values of 0.90 and 0.48 $mL-H_2/mg$-DCW under the irradiation of 10 klux of halogen and fluorescent light, respectively. The optimum growth temperature for hydrogen production was $26^{\circ}C$, and hydrogen production rate was lowered over $30^{\circ}C$. When T. roseopersicina was grown photoheterotrophically under irradiation of 8-9 klux of halogen lamp, the generation time was 4.2 hr. The strains started producing hydrgen from the middle of the logarithmic growth phase and continued until succinate concentration leveled out.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.25-33
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• 2017

This paper reports the optical design of the MR-16 lamp series with a LED second lens and an aspherical plano-convex lens suitable for a simple and rapid injection molding fabrication method. The fabrication and performance evaluation of the MR-16 lamp series, which was designed with a narrow angular distribution of luminous intensity, were conducted to replace halogen lamps with LED lamps. Four types of LED lamps were fabricated, which have angular distributions of luminous intensity of $22.4^{\circ}$, $31.1^{\circ}$, $37.3^{\circ}$, and $59.9^{\circ}$ and luminous efficiencies of 76.5 lm/W, 75.2 lm/W, 72.0 lm/W, and 77.8 lm/W, respectively, while their spreading angles with an illuminance uniformity of 81% were $3^{\circ}$, $15^{\circ}$, $22^{\circ}$, and $49^{\circ}$, respectively. After eliminating a yellow tail of the LED lamps using a diffusion sheet, the angular distributions of the luminous intensity were measured to be $20.8^{\circ}$, $31.5^{\circ}$, $37.8^{\circ}$, and $68.7^{\circ}$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.757-758
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• 2010

At the time of medical treatment and surgical operation, halogen lamp and plasma lamp were mainly used as luminous source for lighting. These two luminous sources have drawbacks that the life of lamps are not long, various problems are brought about due to excessive heat generation and its volume is very big because of cooling device. Accordingly, in this research a ring light was developed so that a partial shadowless shooting for the patient's affected area at the medical treatment room and surgical operation room using high luminance LED for which attention is being paid as new lighting parts for medical purpose. LED which was applied to the development used high luminance three color LED for full color for which various color materialization and the adjustment of radiation intensity are possible and we can get white light in order to emphasize the delicate expression for generic tone of shooting object, strong highlight, simple shadow and three dimensional effect at the time of close-up shadowless shooting of the affected area.

• 보존과학연구
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• s.33
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• pp.85-97
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• 2012

In this study, reliability assessment was carried out on UV(ultraviolet) indicators for the application of the indicator method on cultural heritages. As a result, some UV indicators(L, K, and M) proved to be unsuitable due to their low reactivity to UV and high reactivity to RH(relative humidity). On the other hand, indicator S showed considerable color changes and fading due to UV-B and UV-C according to the integral amount of UV irradiation. Indicator S showed the most distinct reaction to UV and a remarkable applicability to exhibition light, which are used in museums. Therefore, UV indicator S is an easy and useful monitoring tool for light environment management in cultural- property conservation facilities.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.306-315
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• 2021

This study analyzed the effects of light-shielding curtains and halogens on spectrum when acquiring hyperspectral images in a greenhouse. The image data of tarp (1.4*1.4 m, 12%) with 30 degrees of angles was achieved three times with four conditions depending on 14 heights using the automatic image acquisition system installed in the greenhouse at the department of Southern Area of National Institute of Crop Science. When the image was acquired without both a light-shielding curtain and halogen lamp, there was a difference in spectral tendencies between direct light and shadow parts on the base of 550 nm. The average coefficient of variation (CV) for direct light and shadow parts was 1.8% and 4.2%, respective. The average CV value was increased to 12.5% regardless of shadows. When the image was acquired only used a halogen lamp, the average CV of the direct light and shadow parts were 2 .6% and 10.6%, and the width of change on the spectrum was increased because the amount of halogen light was changed depending on the height. In the case of shading curtains only used, the average CV was 1.6%, and the distinction between direct light and shadows disappeared. When the image was acquired using a shading curtain and halogen lamp, the average CV was increased to 10.2% because the amount of halogen light differed depending on the height. When the average CV depending on the height was calculated using halogen and light-shielding curtains, it was 1.4% at 0.1m and 1.9% at 0.2 m, 2 .6% at 0.3m, and 3.3% at 0.4m of height, respectively. When hyperspectral imagery is acquired, it is necessary to use a shading curtain to minimize the effect of shadows. Moreover, in case of supplementary lighting by using a halogen lamp, it is judged to be effective when the size of the object is less than 0.2 m and the distance between the object and the housing is kept constant.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.782-786
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• 2009

Thiocapsa roseopersicina NCIB 8347은 purple sulfur bacteria이며 광합성종속영양 조건에서는 nitrogenase 효소계가 유도되어 질소를 고정하며, 수소를 발생한다. 또한 광합성독립영양 조건에서는 hydrogenase 효소계가 유도되어 3~4개 종류의 특성이 다른 hydrogenase가 membrane에 결합되어 있거나, cytoplasma에 존재하며, 이 중의 일부는 산소농도와 온도의 상승에도 비교적 안정하다. 본 연구에서는 T. roseopersicina NCIB 8347이 광합성종속영양 조건에서 수소를 생산할 수 있는 제반 배양조건을 최적화하고, nitrogenase와 일부 hydrogenase역가를 측정하여 purple non-sulfur bacteria, Rhodobacter sphaeroides KD131의 nitrogenase와 비교하여 수소생산을 최적화하였다. 할로겐램프를 8-9 $Klux/m^2$로 조사할 때와 배양온도 $26{\sim}30^{\circ}C$, 배양시간 72시간에서 균체 성장과 수소생산이 가장 높았다. T. roseopersicina NCIB 8347는 광합성 독립영양, 종속영양 조건에서 모두 성장 할 수 있었다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.8
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• pp.950-958
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• 1988

We have implemented a RTA system using W-halogen lamps and tried to recrystallize the phosphorus ion implanted amorphous silicon on insultor (SOI) taking advantages of seeding window. The purpose of this study is to investigate the possibility of a typical crystalline orientation occurred during the solidifying process of molten amorphous silicon layer. Experimental results show that several twin boundaries are found on the seeding window region after annealing for 15 sec at 1040\ulcorner. These twin boundaries represent that the recrystallization is partialy possible and when the annealing is done at 1150\ulcorner, (100) etch pits with <110> facets are found on the solidified amorphous silicon layer. Consequently, Hall mobility of recrystallized silicon film is measured and the thermal behavior of grain boundary is also observed by SEM.