• 한국산학기술학회논문지
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• 제21권10호
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• pp.64-71
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• 2020

본 연구에서는 미세조류 Haematococcus pluvialis의 성장에 미치는 배양 배지와 광원의 영향을 평가하기 위해 제한 성분 배지인 Modified Bold's Basal Medium (MBBM) 와 상업용 액체 비료 배지인 Neo, 그리고 파장이 서로 다른 7개의 광원을 사용하여 H. pluvialis를 39일 동안 배양하고 성장률을 비교하였다. 그 결과 제한 성분 배지인 MBBM에서 H. pluvialis의 성장은 fluorescent light 광원에서 세포 성장이 가장 높게 나타난 반면, blue+red LED에서 세포 성장이 가장 낮게 나타났다. 상업용 배지인 Neo에서 H. pluvialis의 성장은 fluorescent light 광원에서 세포성장이 가장 높게 나타났으며, blue LED에서는 세포 성장이 가장 낮음이 확인되었다. 본 연구를 통해 MBBM 배지가 Neo 배지보다 우수한 결과를 나타내었으며 또한, MBBM 배지를 이용하여 fluorescent light에서 성장한 미세조류는 본 연구에서 가장 우수한 세포 성장 결과를 보였다. 이러한 결과는 이차대사산물 생산을 위한 H. pluvialis 배양에서 배지, 광원과 광량을 최적화한 것으로 미세조류 대량 배양에 기초 자료로써 유용하게 활용될 것이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.321-323
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• 2006

The light gets darker from center to edge of the light source. Therefore, we can find the center of the sun using shading histogram. Moreover, we can track the exact position of the sun with the shading histogram. In this paper, we propose a new technique using image-processing of digital camera, in order to locate the position of the sun.

• 여성건강간호학회지
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• 제21권3호
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• pp.197-206
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• 2015

Purpose: The purpose of this study was to examine the effects of light therapy on sleep disturbance and depression in climacteric women with menopausal symptoms. Methods: The research design was a nonequivalent control group pre test-post test design. Data were collected from September 29, 2013 to November 11, 2013. Participants included 17 climacteric women in an artificial light therapy group, 17 climacteric women in a sun light therapy group and 16 climacteric women in a control group. Measures consisted of the sleep disturbance, depression, melatonin, and serotonin. Results: There was a statistically significant difference of Korean Sleep Scale A (F=53.87, p<.001), and melatonin (F=31.19, p<.001) among three groups. There was a statistically significant difference of Self-Rating Depression Scale (F=121.86, p<.001), and serotonin (F=102.37, p<.001) among three groups. Conclusion: Artificial and sun light therapy can be applied as a supportive nursing intervention to subjects with sleep disturbance and depression in climacteric women with menopausal symptoms. Artificial and sun light therapy is expected to be a complementary alternative intervention for health management of the subjects with sleep disturbance and depression in climacteric women with menopausal symptoms.

• 한국환경과학회지
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• 제2권4호
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• pp.279-289
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• 1993

자연광 및 여러 파장의 광선과 NAA, GA$_3$, BA 등의 식물호르몬을 옥수수 유식물에 처리하여 엽록소-단백질 복합체 형성에 미치는 효과를 조사하였다. 자연광하에서 3 종류의 호르몬 처리는 전체적으로 엽록소-단백질 복합체, 특히 LHCP-1과 LHCP-3의 형성을 촉진하였으나, 2 종류의 호르몬 조합은 엽록소-단백질 형성에 효과적이지 못하였다. LHCP-1, CPA 및 LHCP-3 등의 광계 II 관련 엽록소 형성에 있어서 백색광은 자연광에 비하여 효과가 적었으나 적색광은 효과적이었다. 적색광하에서 식물호르몬의 단독처리는 엽록체 발달 초기에 광계 II의 엽록소-단백질의 양적 증가를 유도하였다. 한편, 적색광하에서 2 종류의 호르몬 조합 처리도 자연광하에서의 처리와는 대조적으로 광계 II의 엽록소-단백질 형성에 매우 효과적이었다. 이와 같은 결과는 광선처리의 효과가 호르몬처리 효과보다 엽록소-단백질 복합체 형성에 중요한 인자로 작용한다는 것을 시사해 준다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.352-357
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• 2008

Using the artificial sun, namely the BIOSUN, we can control the sun light according to the latitude and longitude and for the seasonal changes and apply that to subway stations. By doing this, we can expect three effects, a. allowing the plants to grow inside the stations which will in turn contribute to improving air purity, controlling humidity, and reducing dust for pleasant environment, b. pleasant environment will foster positive emotional responses of the passengers and that would increase the satisfaction, and c. fostering good service for the citizenry and establishing an environmental friendly image of the Seoul Metro Subway System. The purpose of this thesis paper is to contemplate on the uses of the artificial sun powered by the microprocessor of a Light Emitting Diode (LED) in controlling the light and how the light can be utilized in facilitating photosynthesis that would allow plants to grow inside subway stations.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.274-277
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• 2006

KARI is currently developing a geostationary ocean color imager (GOCI) for COMS. We report the progress in integrated optical modeling and analysis for stray light suppression and the end-to-end instrument performance verification including in-orbit calibration. The Sun is modeled as the emitting light source and the selected area around Korean peninsular as the observation target that scatters the sun light towards GOCI in orbit. The optical ray tracing employing active geometric scaling was then used for precise characterization of the spatial and radiometric performance at the instrument focal plane. The analysis results show positive reduction in the simulated stray light level with the design improvement including baffles. It also indicates that the ray traced in-orbit radiometric performances are effective tools for the independent assessment of more traditional linear and quadratic equation based estimation of water leaving radiance. The concept of integrated GOCI optical model and the computational method are presented.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.480-480
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• 2007

This paper performed the basic study for developing the light therapy equipment for medical treatment. We developed the equipment for medical therapy using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, and to control the change of output value, TLC5941 was used. Control stage is divided into 4 step by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and the output of a high brightness LED could be controlled, stage by stage.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.70-77
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• 2020

미세조류는 광합성을 수행하는 독립영양생물로 배양 환경을 변화시켜 미세조류 유래 유용물질의 축적을 증대시킬 수 있다. 본 연구에서는 미세조류 S. obliquus의 세포 성장에 주요 인자인 배지와 광원의 영향을 평가하기 위해 MBBM, Neo 배지와 7가지의 광원을 사용하여 39일 동안 배양하여 세포 성장을 측정하였다. 그 결과 MBBM과 Neo 배지에서 성장한 S. obliquus의 경우, Fluorescent light 광원과 Red2 LED (R660) 광원에서 세포 성장이 가장 높게 관찰되었고, Infra Red LED (R741) 광원에서는 세포 성장이 가장 낮게 관찰되었다. 평균 세포 성장률은 MBBM 배지에서 17.7 %, Neo 배지에서 15.4 %의 성장률을 확인하였다. MBBM과 수생식물 생산용 영양소를 포함한 Neo 배지의 건조세포무게(dry cell weight)를 비교하였을 때, Blue LED (B450)를 제외한 LED 광원에서 Neo보다 많은 세포 성장이 높은 것이 확인되었다. 이는, MBBM 배지가 Neo 배지보다 미세조류 세포량 증대에 보다 적합함이 증명되어 향후 미세조류 대량배양을 통한 유용물질 생산에 있어 광원 선정이 중요하다는 것이 확인되었다.

• 한국재료학회지
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• 제24권6호
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• pp.305-309
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• 2014

When sunlight irradiates a boron-doped p-type solar cell, the formation of BsO2i decreases the power-conversion efficiency in a phenomenon named light-induced degradation (LID). In this study, we used boron-doped p-type Cz-Si solar cells to monitor this degradation process in relation to irradiation wavelength, intensity and duration of the light source, and investigated the reliability of the LID effects, as well. When halogen light irradiated a substrate, the LID rate increased more rapidly than for irradiation with xenon light. For different intensities of halogen light (e.g., 1 SUN and 0.1 SUN), a lower-limit value of LID showed a similar trend in each case; however, the rate reached at the intensity of 0.1 SUN was three times slower than that at 1 SUN. Open-circuit voltage increased with increasing duration of irradiation because the defect-formation rate of LID was slow. Therefore, we suppose that sufficient time is needed to increase LID defects. After a recovery process to restore the initial value, the lower-limit open-circuit voltage exhibited during the re-degradation process showed a trend similar to that in the first degradation process. We suggest that the proportion of the LID in boron-doped p-type Cz-Si solar cells has high correlation with the normalized defect concentrations (NDC) of BsO2i. This can be calculated using the extracted minority-carrier diffusion-length with internal quantum efficiency (IQE) analysis.

• 한국정밀공학회지
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• 제29권11호
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• pp.1170-1173
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• 2012

We have investigated the LED lens eccentricity effect on light intensity distribution. For the purpose, we introduced an equation of focal length for paraboloid, and then made a comparative analysis of the theoretical result and 3-D simulation result.