• 제목/요약/키워드: Sun light

검색결과 1,942건 처리시간 0.033초

Effect of Light Source on Organic Acid, Sugar, and Flavonoid Concentrations in Buckwheat

  • Kim, Sun-Lim;Lee, Han-Bum;Park, Cheol-Ho
    • 한국작물학회지
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    • 제47권1호
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    • pp.42-47
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    • 2002
  • The major free sugars of buckwheat plants were fructose, glucose, and maltose but their contents and compositions were influenced by the different wavelength of light. Free sugar contents of Clfa 39 (Fagopyrum tataricum) were higher than those of Yangjul-maemil (Fagopyrum esculentum) regardless of the light sources. As treated with red and blue light, the free sugar contents in the leaves of buckwheat plants were slightly increased, but their contents in the stems and flowers were lower than those of natural light condition. Under the natural light condition, maltose was detected in every tissues of buckwheat plants, but as treated with blue and red light, it was not detected in the flowers of buckwheat plants. Citric, malic and acetic acid were detected as major organic acids in buckwheat plants. Red and blue lights decreased the total organic acid contents in buckwheat plants as compared with natural light condition. It was considered that blue light are less active than red light for the accumulation of organic acids. Tataric acid was detected only in the leaves of buckwheat plants, however, as treated with red and blue light, it was not detected in the leaves of Clfa 39. Flowers of Yangjul-maemil contained a considerable amount of rutin and quercitrin. Only small amount of quercitrin was detected in leaves, but it was not detected in stems. On the other hand, Clfa 39 leaves contained a considerable amount of rutin, quercetin and small amount of quercitrin, but quercitrin and quercetin were detected only in the stems of Clfa 39. Red and blue lights significantly decreased the contents of rutin, quercitrin, and quercetin in buckwheat plants as comparing with natural light condition. Rutin content in the flowers of Clfa 39 was increased under the red and blue light conditions.

무선센서네트워크를 위한 TCP-Light 프로토콜 설계 (Design of TCP-Light Protocol for wireless sensor network)

  • 김선영;진교홍
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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    • pp.477-480
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    • 2008
  • 무선센서네트워크로부터 전달되는 데이터를 수집하거나, 센서노드를 제어하고 감시하기 위해서는 센서노드와 인터넷 상의 호스트가 연결될 필요가 있다. 그러나 무선센서네트워크는 기존의 인터넷과는 달리 노드의 하드웨어적인 제약이 많으며, 높은 패킷 에러율을 보인다. 이에 따라 유선망에 연결된 호스트의 TCP 프로토콜은 성능이 급격히 떨어지므로 이를 해결하기 위한 방안이 모색되어야 할 것이다. 즉, 센서노드의 하드웨어적인 문제점, 무선망의 환경적인 요소 등을 고려한 새로운 TCP 프로토콜이 개발되어야 한다. 따라서 본 논문에서는 기존의 TCP 프로토콜과 호환되며, 무선센서노드에서도 사용가능 한 TCP-Light 프로토콜을 제안하였다. 제안된 TCP-Light 프로토콜은 메모리 소모율이 낮으며, 망상의 메시지 수를 줄일 수 있다.

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광섬유를 이용한 자연채광시스템 적용 연구 (A Study on the Application of Sunlight System Using an Optical fiber)

  • 안승주;한상주;홍우식;최창호;이종혁
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 추계학술대회 초록집
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    • pp.51.2-51.2
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    • 2010
  • In recently, interests in the New & Renewable Energy are increasing because of exhaustion of fossil energy and limit of greenhouse gas emission all over the world. Furthermore, improvements in living standards and high-raise Buildings due to the industrial growth require a lot of sunlight in the interior space. Sunlight system gets the natural light into the indoor dark space. There are a lot of type of systems which are reflector type, duct type, optical fibers type and so on. And these systems consist of light-collection module, light-transporting module and light-emitting module. In this research, we installed optical fiber sunlight system in our head office building and tested the system's performance and efficiency. Optical fiber sunlight system is closely connected with hour of sunlight, due to the system have to chase the sun for the solar concentrating, and the system's light-collection and light- transporting efficiency is important factors in the system's performance. As a result of the test, system can be used about 5.66 hours on average in a day, and it has a about 3.21 times collection efficiency and 5.5% transmission loss.

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박형 도광판의 음각, 양각 마이크로 패턴 성형성에 관한 연구 (Study on the gate cutting of light guiding plate for mobile using quenching element)

  • 황철진;김종선;민인기;김종덕;윤경환
    • Design & Manufacturing
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    • 제2권5호
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    • pp.1-4
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    • 2008
  • LCD-BLU (Liquid Crystal Display - Back Light Unit) is one of kernel parts of LCD unit and it consists of several optical sheets(such as prism, diffuser and protector sheets), LCP (Light Guide Plate), light source (CCFL or LED) and mold frame. The LGP of LCD-BLU is usually manufactured by forming numerous dots with $50-200{\mu}m$ in diameter on it by erosion method. But the surface of the erosion dots of LGP is very rough due to the characteristics of the erosion process during the mold fabrication, so that its light loss is high along with the dispersion of light into the surface. Accordingly, there is a limit in raising the luminance of LCD-BLU. Especially, the negative and positive micro-lens pattern fabricated by modified LiGA with thermal reflow process was applied to the optical design of LGP.

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고휘도 발광 Chip 소자를 이용한 빛의 명암도 분석 (Estimation of the Light Intensity by Using Bright-Chip LED Sensory System)

  • 최주현;김지선;정구인;이태희;김아희;오한별;박희정;김경섭;전재훈
    • 전기학회논문지
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    • 제62권9호
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    • pp.1290-1296
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    • 2013
  • The light intensity which represents the relative amount of brightness and darkness is very important feature to discern the color hue and its relevant information. With this aim, we devise a new optical system and method to analyze the light intensity. Our suggested system including a phototransistor and white-high-brightness chip light-emitting diode intend estimate the contrast value utilizing Image Research Institute(I.R.I.) Hue & Tone samples which includes 120 color sheets arranged by the color hue and tone. As a result, we confirmed that the brightness of the color checker can be accurately estimated by a high-brightness light-emitting-diode optical system.

초록저고리와 치마색의 톤 변화에 따른 한.미 여대생의 선호도 연구 (The Study in the Preference of Korean and American Students with the tone Variation of Green Jacket and Skirt Color)

  • 강경자;김선미
    • 한국생활과학회지
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    • 제15권4호
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    • pp.597-609
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    • 2006
  • The purpose of the research was to compare the preference of coloration of traditional Korean dress according to tone variation of green jacket by Korean and American women college students. The results of research can be summarized as follows. Korean students preferred skirt of vivid red color and light green jacket, but American students did not like it. Korean students did not like the skirt and jacket of same color, but American students preferred it. Both Korean and American students preferred skirt and jacket of different tone. Korean students liked skirt of dull blue and jacket of light dull green, skirt of dark blue and jacket of vivid, dull green. American students liked skirt of vivid violet and jacket of vivid dull, dark green. They also liked skirt of light yellow and jacket of light green, light skirt of blue, violet and jacket of light, dull, dark green, skirt of dark blue and vivid, light, dull gueen, skirt of dark violet and jacket of dull, dark green.

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식기간 동안의 천리안 기상영상에 대한 미광의 영향 분석 (Stray Light Impacts on the COMS MI Images during the Eclipse Period)

  • 진경욱;박봉규
    • 항공우주기술
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    • 제11권2호
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    • pp.12-18
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    • 2012
  • 이 논문에서는 식기간 동안 미광(stray light)에 의해 천리안 기상 영상이 받게 되는 영향에 대해 분석하였으며 미광의 영향을 제거하기 위한 방법 또한 모색하였다. 기상영상의 경우 식기간 동안 미광의 영향을 받아 영상의 왜곡 (줄무늬 등)문제가 발생한다. 미광의 영향에 대한 정량적 분석이 천리안위성의 궤도상 시험기간 동안에 이루어졌으며, 천리안위성 기상탑재체의 총 4개 적외 채널에 대해 태양과의 거리에 따른 미광의 영향이 분석되었다. 본 연구에서는 계산된 천리안위성의 식기간 자료를 바탕으로 미광의 영향이 매우 강한 사례를 선정하여 적외채널 영상의 미광에 의한 오염 정도를 조사하였다. 또한 영상에 나타난 미광의 영향을 두 개의 열적외 채널을 이용하여 단파적외 채널을 대체하는 방법이 유효함을 확인 하였다.

Factors associated with Intermittent and Light Smoking among Korean High School Students: Intermittent and Light Smoking among Korean Adolescents

  • Ra, Jin Suk;Kim, Hye Sun;Cho, Yoon Hee
    • 지역사회간호학회지
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    • 제29권1호
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    • pp.33-40
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    • 2018
  • Purpose: The purpose of this study was to identify factors associated with intermittent and light smoking among Korean high school students. Methods: In this cross-sectional study, we employed secondary data from the 2015 Korea Youth Risk Behavior Web-Based Survey, and used the biopsychosocial model as a framework. The analysis was performed using the data of 2,851 high school students who smoked. We defined intermittent and light smoking as smoking on 1 to 29 days in a 30-day period and no more than 10 cigarettes per day. A logistic regression analysis using the complex samples procedure was conducted. Results: Among all the participants, 1,231 (43.2%) were intermittent and light smokers. Factors significantly predicting intermittent and light smoking were gender and grade (biological factors); subjective stress (psychological factor); and mother's smoking, sibling's smoking and academic achievement (sociocultural factors). Conclusion: In smoking cessation programs, health care providers both at school and in the community should consider the unique biological, psychological, and sociocultural characteristics of intermittent and light smoking behavior among high school students.

고분자 전기 발광 다이오드(PLEDs)를 위한 포토리소그라피 패터닝 방법에 관한 연구 (The Investigation of Photolithographic Patterning Method for Polymer Light Emitting Diodes (PLEDs))

  • 김미경;이정익;김덕일;황치선;양용석;오지영;박상회;추혜용;김숙경;황도훈;이형종
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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    • pp.106-108
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    • 2004
  • We have investigated the photolithographic patterning method of light emitting polymer film for polymer light emitting diodes (PLED). Blue light emitting polymers based on polyfluorene, which can be cured photochemically to yield an insoluble form, have been synthesized using Ni(0) mediated Yamamoto polymerization. The relationship between patterning property and several variables such as the intensity of the exposed UV light, the concentrations of additives, has been studied by using optical microscope analysis, UV/visible spectroscopy, and photoluminescence. We have successfully fabricated PLEDs composed of the patterned emissive layer and their electroluminescence property has been also investigated. In this presentation, the detailed photolithographic patterning method and its application for polymer light emitting display will be discussed.

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염료감응형 태양전지의 고효율화를 위한 $Alq_3$가 코팅된 FTO기판 제작 (Optimization of $Alq_3$-coated FTO substrate for high efficient of DSSC)

  • 박아름;박경희;구할본;박복기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.241-241
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    • 2010
  • Recently high and persistent spontaneous buildup of a surface potential (SP) upon vacuum deposition of tris (8-hydroxyquinolinato) aluminum (III) ($Alq_3$), which is widely used for organic light emitting devices. The removal of the giant surface potential by visible light irradiation has also been reported. In this study, we coated $Alq_3$ on the FTO substrate and raise the capacity for absorbing sun light. The $Alq_3$ which is green light emitting diode emits light at wavelengths between 500 and 550nm. If we apply one's FTO/$Alq_3$ substrate in one's DSSC, we could get higher energy conversion efficiency because the N719 dye that we used for fabricating the DSSC emits light just at near 540nm. The energy conversion efficiency of approximately 4.8 % at the condition of irradiation of AM 1.5 (100 mW/$cm^2$) simulated sunlight, and the $J_{sc}$ is 12.0 mA/$cm^2$, $V_{oc}$ is 0.71 V, FF is 0.56, respectively.

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