• Title/Summary/Keyword: infrared radiation

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The Effect of Far Infrared Radiation of $\beta$-Spodumene Glass-Ceramics Flims Coated on Iron Substrate by Sol-Gel Technique (졸-겔법에 의한 금속기판상의 $\beta$-spodumene 결정성유리의 박영도포와 원적외선상세성)

  • 양중식;신현택;박종옥
    • Journal of the Korean institute of surface engineering
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    • v.27 no.2
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    • pp.99-108
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    • 1994
  • Films of glass-ceramics $Li_2O-Al_2O_3-SiO_2$(LAS)system were prepared on substrate of an iron plate(SCP) by sol-gel technique using metal alkoxide such as Si$(OC_2H_5)_4$,Al$(OC_2H_9)_3$) and Ti$(OC_2H_6)_4$). Sol which was made by means of simple spray coating, on the substrate was hydrolyzed at 75~$80^{\circ}C$ in moisture cabinet (80~90 % humidity) to form the multicomponent gel. The films up to about 0.8~1.0$mu extrm{m}$ in thickness can be obtained by repeating operation, spraylongrightarrowhydrolysis and condensationlongrightarrowdryinglongrightarrowheating and crystallization at $700^{\circ}C$ for 3~5min. The far-infrared radiation spectra of the coated films on substrate were examined by FT-IR and of films was also observed by scanning electron micrograph technique. The thermal evaluation of the gel-film is followed by TG/DTA measurements. The structure evaluation is followedd X-ray diffraction. These results suggest that this process is applicable to far-infrared radiat at thin film technique.

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Probing Cosmic Near Infrared Background using AKARI Data

  • Seo, Hyun Jong;Matsumoto, Toshio;Jeong, Woong-Seob;Lee, Hyung Mok;Matsuura, Shuji;Matsuhara, Hideo;Oyabu, Shinki;Pyo, Jeonghyun;Wada, Takehiko
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.34.1-34.1
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    • 2013
  • The first generation stars in the universe are not observed as discrete objects by using current observational facilities, but their contributions are redshifted to the near infrared wavelength bands at present universe. Therefore, investigation of background radiation at near infrared is important for the study of the first stars. In this study, we present new observations of spatial fluctuations in sky brightness toward the north ecliptic pole using data from AKARI. Among pointed observation program of AKARI, we used two pointing surveys named Monitor field and NEP wide field at three wavelength bands 2.4, 3.2, and 4.1 ${\mu}m$. To obtain spatial fluctuations from observed images, first of all, we exclude pixels affected by resolved foreground objects and then obtain diffuse map which consists of diffused radiation only. Because the diffuse map contains not only cosmological components but also various foreground components, in order to detect cosmological components, we estimate the contributions of foreground components separately. The results of this study show that there remains excess spatial fluctuation that cannot be explained by known foreground sources. This work is based on observations with AKARI, a JAXA project with the participation of ESA.

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Probing Cosmic Near Infrared Background using AKARI Data

  • Seo, Hyun Jong;Matsumoto, Toshio;Jeong, Woong-Seob;Lee, Hyung Mok;Matsuura, Shuji;Matsuhara, Hideo;Oyabu, Shinki;Pyo, Jeonghyun;Wada, Takehiko
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.35.1-35.1
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    • 2013
  • The first generation stars in the universe are not observed as discrete objects by using current observational facilities, but their contributions are redshifted to the near infrared wavelength bands at present universe. Therefore, investigation of background radiation at near infrared is important for the study of the first stars. In this study, we present new observations of spatial fluctuations in sky brightness toward the north ecliptic pole using data from AKARI. Among pointed observation program of AKARI, we used two pointing surveys named Monitor field and NEP wide field at three wavelength bands 2.4, 3.2, and 4.1 ${\mu}$. To obtain spatial fluctuations from observed images, first of all, we exclude pixels affected by resolved foreground objects and then obtain diffuse map which consists of diffused radiation only. Because the diffuse map contains not only cosmological components but also various foreground components, in order to detect cosmological components, we estimate the contributions of foreground components separately. The results of this study show that there remains excess spatial fluctuation that cannot be explained by known foreground sources. This work is based on observations with AKARI, a JAXA project with the participation of ESA.

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Airborne Remote Sensing of Evapotranspiration over Rice Paddy

  • Chen, Y.Y.;Liou, Yuei-An
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.351-353
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    • 2003
  • We present a retrieval scheme for the remote sensing of evapotranspiration (ET) over rice paddy. To perform the retrieval, high-resolution airborne imagery of multi-spectral visible and thermal infrared data, and ground-based meteorological measurements are utilized. Our ET retrieval scheme is based on the basic principal of surface energy budget, which is a result of balance in longwave and shortwave radiation, latent heat, sensible heat, and energy flux into the ground. To partition the latent and sensible heat fluxes of interest from the energy balance equation, three basic parameters are of most concern, including albedo, surface temperature, and normalized difference vegetation index (NDVI). The NDVI and albedo can be easily derived from the visible and near infrared spectral data, while the surface tem-perature can be determined through the analysis of the infrared data with the Stefan Boltzmann law. From the airborne imagery taken on 28 April 2003, we observe very good dry and wet pixels that can be easily corre-sponded to the radiation and evaporation controlled crite-ria, respectively, and, hence, for the further use in defin-ing the evaporative fraction needed to partition sensible and latent heat fluxes from the net energy flux. The de-rived ET is compared with the in situ measurements.

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Effects of Air Blast Thawing Combined with Infrared Radiation on Physical Properties of Pork

  • Hong, Geun-Pyo;Shim, Kook-Bo;Choi, Mi-Jung;Min, Sang-Gi
    • Food Science of Animal Resources
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    • v.29 no.3
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    • pp.302-309
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    • 2009
  • This study investigated the effects of infrared (IR) radiation combined with air blast thawing on the physical properties of pork. Regardless of air velocity, increasing IR dosage produced an exponential increase in the thawing rate of pork. This rate increased further when air blast velocity was increased. IR treatments showed significantly lower thawing loss than that of 0 Watt treatment, while increasing air velocity significantly increased thawing loss of pork (p<0.05). Increasing both IR power and air velocity tended to decrease the cooking loss of pork. Moreover, increased IR power tended to decrease the water holding capacity and shear force of pork. The shear force changes were not significant (p>0.05). Shear force also increased with increasing air velocity. In addition, the higher the air velocity the higher the shear force of pork. In Commission Internationale de l'Eclairage (CIE) colour determination, control of temperature prevented discolouration from overheating of sample surface. The results suggest that IR dosage combined with air blast has potential in thawed meat quality aspects, and that humidity control could prevent surface drying.

A study on energy saving and economic analysisy calculation of far-infrared radiation oven (원적외선 복사오븐의 에너지 절감평가 및 경제성분석)

  • Kim, Yong-Ha;Yoo, Jeong-Hui;Lee, Gwong-Sung;Heo, Dong-Lyul;Yon, Hyeon-Su;Lee, Seong-Hui
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1270-1271
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    • 2011
  • A study on the energy consumption(weigh against of the energy consumption for analyzed oven) and the energy consumption of follow cooking time (weigh against of cooking time for analyzed oven)through weigh against far-infrared radiation oven and other system. for this study, analysis the energy consumption follow temperature change and calculate the energy consumption until come to saturation temperature. also, the energy consumption is measured for food analysis follow cooking time. The energy reduced cost and time is estimated.

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UV/IR flame detector using Microprocessor (마이크로프로세서를 사용한 UV/IR 불곶 감지기)

  • 박성진;임병현;임종연;김명원;윤길호
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.215-218
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    • 2001
  • A flame detector responds either to radiant energy visible to the human eye or outside the range of human vision. Such a detector is sensitive to glowing embers, coals, or flames which radiate energy of sufficient intensity and spectral quality to actuate the alarm. An infra-red detectors can respond to the total IR component of the flame alone or in combination with flame flicker in the frequency range of 5 to 30 Hz. A major problem in the use of infrared detectors receiving total IR radiation is the possible interference of solar radiation in the infrared region. When detectors are located in places shielded from the sun, such as vaults. filtering or shielding the unit from the sun's rays is unnecessary. In this study, we proposed method for redue a false alarm with using filtering & sensor technology for distinguish of causes of raise a false alarm and pure flame.

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Matrix Infrared Spectra and DFT Computations of 2H-Azirine Produced from Acetonitrile by Laser-Ablation Plume Radiation

  • Cho, Han-Gook
    • Bulletin of the Korean Chemical Society
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    • v.35 no.7
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    • pp.2093-2096
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    • 2014
  • 2H-azirine, a less known acetonitrile isomer, is observed in matrix IR spectra from the precursor exposed to radiation from laser ablation of transition-metals. Its vibrational characteristics confirm the previous results, and those for the deuterated and $^{13}C$ substituted isotopomers are also newly reported. The weak absorptions are traced to the low production yield due to its high energy and low extinction constants. IRC computations reveal smooth inter-conversion between 2H-azirine and $CH_2NCH$, providing a rationale for the observed variation of their relative contents during photolysis.

Broadening of absorption spectrum in a p-type InGaAs-InAlAs coupled Quantum well (p형 InGaAs-InAlAs 결합양자우물을 이용한 흡수계수스펙트럼의 broadening)

  • 김경환;김성준
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.3
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    • pp.34-40
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    • 1997
  • Intervalence subband absroption of normally incident infrared radiation in p-type InGaAs-InAlAs coupled quantum well (CQW) is theoretically investigated by the multiband effective mass formalism. By solving a 4*4 luttinger-kohn hamitonian, we calculate valence subband structures, intervalence subband transition matrix elements, and absorption coefficient spectrum in the CQW which consists of a wider well, a thinner well and a barreir between them. Using the flexible design parameters given to the valence band CQW structure, we show that the absorption coefficient profile can be tailored. For a carefully designed CQW, theabsorption coefficient cn be made to maintain a large value over a wider wavelength range of incident infrared radiation compared with that shown in intersubband absorption in usual single quantum well.

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A Study on Scale Busting and Preventing Effect of Coating Ceramic Ball (코팅 세라믹볼의 방청효과에 관한 연구)

  • 하윤식;김학용;김수진;백우현
    • Journal of Environmental Science International
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    • v.11 no.10
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    • pp.1117-1123
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    • 2002
  • Coating ceramic balls activate water molecular in water as radiate far-infrared radiation of high efficiency, and then prevent formation of scale and corrosion of pipe. Therefore, but only keep away drop of heat exchange efficiency of boiler, not also remove formed scale. As a result, pipe of boiler has clean and has form thin protection film in inner of pipe. Also, the water treated by rust preventing system using the ceramic balls, that is harmless, tasteless, odorless, and non-toxicity in the human body, and it can use drinking water. This rust preventing system can save energy and protect environment.