• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.409-416
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• 1998

Owing to their high growth rate, marine microalgae such as Chlorella, Spirulina, Porphpidium and Dunaliella have been believed to be potentially useful for the production of foods, drugs and energy from light, $CO_2$ and minerals. In this study, we investigated the relationship between the growth and fatty acid composition in the blue green alga Spirulina platensis when the temperature and light intensity of culture conditions were changed. The optimal growth conditions for Spirulina platensis from the biomass and lipid contents were $30^{\circ}C$ on 6391 $\mu$E/$m^3$/sec and $35^{\circ}C$ on 4235 $\mu$E/$m^3$/sec. The difference of lipid contents between exponential phase and stationary phase were very large according to growth conditions. According to growth conditions the fatty acid compositions of Spirulina platensis differed, but regardless of growth conditions the main fatty acids were C16 : 0 and C20 : 0 in saturated fatty acid, C16 : 1, C18 : 1 and C 18 : 2 in unsaturated fatty acid.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.19-37
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• 2017

Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS-DNB) data provides a much higher capability for observing and quantifying nighttime light (NTL) brightness in comparison with Defense Meteorological Satellite-Operational Linescan System (DMSP-OLS) data. In South Korea, there is little research on the detection of NTL brightness change using VIIRS-DNB data. This study analyzed the spatial distribution and change of NTL brightness between 2013 and 2016 using VIIRS-DNB data, and detected its spatial relation with possible influencing factors using regression models. The intra-year seasonality of NTL brightness in 2016 was also studied by analyzing the deviation and change clusters, as well as the influencing factors. Results are as follows: 1) The higher value of NTL brightness in 2013 and 2016 is concentrated in Seoul and its surrounding cities, which positively correlated with population density and residential areas, economic land use, and other factors; 2) There is a decreasing trend of NTL brightness from 2013 to 2016, which is obvious in Seoul, with the change of population density and area of industrial buildings as the main influencing factors; 3) Areas in Seoul, and some surrounding areas have high deviation of the intra-year NTL brightness, and 71% of the total areas have their highest NTL brightness in January, February, October, November and December; and 4) Change of NTL brightness between summer and winter demonstrated a significantly positive relation with snow cover area change, and a slightly and significantly negative relation with albedo change.

• The Optical Journal
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• s.137
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• pp.54-57
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• 2012

사진이란 빛으로 그리는 그림이다. 카메라의 파인더로 보고 느낀 아름다움을 구도와 구성으로 담아서 적절한 빛을 이용하여 사진 안에 담는다. 풍경사진의 기본은 자연이 만들어낸 아름다움과 마주하게 되는 순간부터 시작이다. 아름답고 신비로운 곳으로 걸어 들어가면 카메라 렌즈 안으로 이미 풍경이 녹아든다.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.785-788
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• 2015

In this study, the effect of light irradiation on tyrosinase activity during storage in a low temperature incubator was investigated, with the goal of identifying the appropriate wavelength and intensity of light for inhibiting tyrosinase activity. Fluorescent light and blue light emitting diode (LED) irradiation were found to inhibit tyrosinase activity. In particular, tyrosinase activity was significantly inhibited under high intensity blue LED irradiation, suggesting that the activity of tyrosinase present in vegetables or fruits might be inhibited by LED irradiation. Therefore, blue LED irradiation during food storage and the distribution stage would be useful for ensuring good quality of food, owing to the inhibition of the enzymatic browning reaction.

• Korean Architects
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• v.5 no.2 s.18
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• pp.38-44
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• 1970

• KSBB Journal
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• v.19 no.4
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• pp.257-262
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• 2004

Recently, there is a growing interest in microalgae and the use of microalgae focused on the production of various high value metabolite used in food, pharmaceuticals and cosmetics. The key limiting factor in high density algal cultivation is the light and algal growth is defined by light intensity and light penetration depth into the culture medium. The effect of light with various light paths, S/V ratios, light intensities, and 50% duty cycle on the growth of microalgae was examined to enhance microalgal biomass productivity and photosynthetic efficiency. We confirmed that the utilization of efficient light energy was obtained from 4 cm of diameter, 57.6% of S/V ratio, 62 ${\mu}$mol/㎡/s of light intensity.

• Textile Coloration and Finishing
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• v.7 no.2
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• pp.86-91
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• 1995

탄소 섬유란 높은 강도, 높은 탄성률 등을 갖고 잇는 소재로서, 복합 재료에 이용되고 있다. 최근에는 스포츠 용품에 대해서도 장식성이 필요한 시대가 되어서 탄소 섬유도 착색할 필요가 있게 되었다. 일반 의류용 섬유를 염색할 때 염료가 섬유를 구성하는 분자에 단분자상으로 흡착한다. 섬유란 사실상 투명하기 때문에 빛이 섬유 내부에 흡착된 염료까지 도달하고, 염료는 빛을 흡수하여 발색한다. 그러나 탄소 섬유의 색은 검고, 빛이 섬유 내부까지 미치지 못하기 때문에 만약 탄소 섬유에 염료를 흡착시키더라도 염료는 발색하지 않게 된다. 한편 검은 탄소 섬유를 표백해서 백색으로 만들기 위해 예를 들어 불소와 반응시키면 검은 탄소 섬유가 백색이 되기는 하지만, 이 불소와 반응한 탄소섬유는 대단히 부서지기 쉬워서, 섬유로 사용할 수 없게 된다. 따라서 탄소섬유는 검은 색 그대로 착색시키지 않으면 안된다. 즉 탄소 섬유는 섬유의 표면에 도료와 같은 색소 층을 붙여서 착색하게 된다.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.440-443
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• 2024

한의학의 증상을 파악하는 한의 변증 진단에서 혀의 형태와 색상을 파악하는 것에서 설질과 설태의 색상을 파악하는 것이 핵심이다. 혀 촬영 장치로 촬영하더라도 조명의 빛 종류와 빛 강도, 위치에 따라 컬러가 변환됨에 따라 혀 취득장치의 컬러교정이 필요하다. 컬러교정을 하지만, 오버피팅, 측정 오류와 노이즈 또는 색상 공간의 불균형으로 컬러의 왜곡이 발생할 수 있다. 이 연구에서는 24개의 patch 중에서 오류를 최소화할 수 있는 patch를 선정하는 최적화의 방법을 제시하려 하였다. 24개 patch 중 몇 개의 선택한 patch의 평균값을 구하여, 기준 값으로 변환시키는 변환 행렬을 구하고, 교정 값을 구하고, 교정된 24 patch 값의 평균과 기준 값과의 오차를 구하여 최소가 되는 변환 행렬을 구하였다. 이 방법은 컬러 챠트의 개수를 줄여 장치의 부피를 줄이는데 활용될 수 있다. 또한 이 방법은 외부의 빛이 차단된 촬영장치에서 활용되었지만, 조명조건이 안정된 개방된 공간에서도 스마트폰을 이용하여 촬영하는데 활용 가능할 것으로 예상된다.

• Journal of Korea Game Society
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• v.16 no.1
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• pp.111-118
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• 2016

This paper proposes the mathematical model of Fresnel effect used to illuminate and simulate a surface character model for defense game play. The term illumination is used to represent the process by which the amount of light reaching a surface character model used on game play is determined. The character surface shaders generally use a mathematical model to predict how light will reflect on triangles. The shading normally represents the methods used to determine the color and intensity of light reflected toward the viewer for each pixel representing the character surface model of the game. This model computes the reflection and transmission coefficients and compares simulated results to the Fresnel equations for the real game improvement.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.38-43
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• 2021

Photocurable hydrogels are widely used as 3D printing materials in tissue engineering (e.g., scaffold fabrication) as well as optical fibers (or optical sensors) materials. Photocurable hydrogels can control optical and mechanical properties such as chemical or fabrication conditions. In previous research, we introduced a new 3D printing method to fabricate a freestanding overhanging hydrogel structure without supporting structure. This study was measured and analyzed the difference of the mechanical properties of the photocurable hydrogel according to the light intensity using a micro tensile tester. In practically, it was difficult to perform a direct tensile test on a micro (less than 1 mm) size fiber. In this study, the tensile test of the hydrogel fibers could be measured simply and repeatedly using a paper carrier.