• 제목/요약/키워드: Spectral range

검색결과 949건 처리시간 0.024초

KAISTSAT-4 : A Progress Report

  • Gyeong-Uk Min;Gwang-Seon Yu;Dae-Hui Lee;Jin-Geun Lee;Seung-Han O;In-Su Yuk;Gwang-Il Seon;Ho Jin;Jang-Hyeon Park
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2004년도 한국우주과학회보 제13권1호
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    • pp.51-51
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    • 2004
  • KAISTSAT-4 is to be launched in August 2003 into an orbit at 800 km altitude with the intended mission shared between astrophysics and space physics. The primary objective of its astrophysics mission is to provide spectral sky survey data of hot Galactic plasmas in the far-ultraviolet wavelength range. Far-Ultraviolet Imaging Spectrograph (FIMS) is sensitive to emission line fluxes in 900 - 1175 $\AA$ and 1335 - 1750 $\AA$. (omitted)

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A CRYOGENIC TWO MILLIMETER RECEIVER SYSTEM

  • Lee, Chang-Hoon;Han, Seog-Tae;Park, Yong-Sun
    • Journal of Astronomy and Space Sciences
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    • 제11권2호
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    • pp.232-249
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    • 1994
  • Since we finished the purchase of the cooled Schottky diode mixer receiver made by Radiometer Physics Co. for the 120-170GHz range in October 1991, we have not prepared the PPL hardware and software for this receiver and the ellipsolidal mirror for beam guiding. After these problems were solved, this receiver was installed at the 14m telescope in late December 1993, and used for the confirmation of a spectral line detection and the measurement of the beam efficiency. The beam efficiency is about 36% at 146 GHz.

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Liquid Crystal Display with High and Stable Color Gamut by Using Pre-compensated Tri-chromatic LED Backlight

  • Chiu, Tien-Lung;Lee, Jiun-Haw
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1515-1518
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    • 2007
  • We demonstrate a high color gamut liquid crystal display (LCD) system (>100 %) by using a precompensated tri-chromatic LED-backlight module over a temperature range of (25 to $70^{\circ}C$), whose pre-compensated optical characteristic balances the spectral redshift and intensity decrease due to the temperature rising during operation.

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PQR 레이저의 1km 광섬유 전송 및 자유공간 특성 (1km Optical fiber transmission and free space characteristics of the PQR laser)

  • 김무성;곽규섭;김준연;김무진;권오대
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.322-325
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    • 1999
  • We report fiber guiding experiments on the Photonic Quantum Ring(PQR) laser diode. In the 1km transmission measurements, we find that the PQR performs much better than the VCSEL. This suggests that the PQR laser is very promising candidate for LAN-range optical data communications. On the other hand, we have also fabricated 8$\times$8 PQR laser arrays and measured spatial decays for free space properties without using any guiding optics, which showed about 1m distance of spectral angle sensing.

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Phenol성(性) 화합물(化合物)의 $^{13}C$-핵자기(核磁氣) 공명(共鳴)(II) -Phenol 성(性) Coumarine 유도체(誘導體)의 Chemical Shift에 관(關)하여- ($^{13}C-Nuclear$ Magnetic Resonance of Phenolic Compounds (II) -A Study on the Chemical Shifts of the Phenolic Coumarine Derivatives-)

  • 안병준
    • 생약학회지
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    • 제8권1호
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    • pp.23-29
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    • 1977
  • The $^{13}C-chemical\;shifts$ of the phenolic coumarine derivatives, aesculetin, daphnetin and herniarin were studied on the basis of my previous report. All spectral data found in this report could be utilized to the structure elucidation of the unknown phenolic coumarine derivatives and other phenolic compounds. In addition, it is suggested that a long range coupling may occur in the following structure as represented by arrow.

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표면 반사율에 의한 사과의 색상 선별 (Color Sorting of Apples by Surface Reflectance)

  • 배영환
    • Journal of Biosystems Engineering
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    • 제17권4호
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    • pp.382-395
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    • 1992
  • The surface color of several varieties of apples were expressed quantitatively in xyz chromaticity coordinates. The spectral reflectance of 'Fuji' apples were measured in 400-820 nm range by using a spectrophotometer. Based on the spectrophotometer data and the result of visual sensory test, linear regression models were developed to select wavelengths effective for sorting apples. The models utilized reflectance at single wavelength, and the difference and ratio of the reflectance at two distinct wavelengths. The model which best fitted the visual sensory test data was one utilizing the ratio of the reflectance at 618 nm and 514nm. The correlation coefficient for this model was 0.967. Several other models were also described.

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KTX 차량 곡선부 스퀼 소음 특성 (Analysis of curve squeal noise for KTX train)

  • 이찬우;김재철
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.1187-1190
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    • 2009
  • CURVE SQUEAL NOISE IS THE INTENSE HIGH FREQUENCY TONAL THAT CAN OCCUR WHEN A RAILWAY VEHICLE TRAVERSES A CURVE OR A SWITCH. THE HIGH NOISE LEVEL CAUSES ANNOYANCE FOR PEOPLE WHO LIVE IN THE NEIGHBOURHOOD OF THE SQUEALING RAILWAY TRACK AS WELL AS FOR THE PASSENGERS IN CARS WITH CURVES. THIS PAPER EXAMINES THE SPECTRAL SOUND DISTRIBUTION IN CURVES FOR KTX TRAIN. THE FREQUENCY RANGE IS FROM AROUND 4,000 TO ALMOST 16,000Hz, WITH NOISE LEVELS UP TO 92dB IN CURVE R400.

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Partitioning of Si in Fe-Zr-Si-B Nanocrystalline Alloys

  • Waniewska, A.Slawska;Greneche, J.M.;A.Inoue
    • Journal of Magnetics
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    • 제4권1호
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    • pp.1-4
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    • 1999
  • The microstructure and magnetic properties of$ Fe_{87}Zr_7Si_4B_2$ nanocrystalline alloys were studied by magnetization measurements and M ssbauer spectrometry over a wide temperature range. Three well resolved spectral components have been found and attributed to bcc-Fe grains (with almost pure iron structure), residual amorphous matrix enriched with solute elements and interfaces formed at the grain-matrix boundaries. It has been shown that, contrary to the expectation, during crystallization the atomic segregation occurs leading to the formation of primary bcc-Fe grains and the partition of Si atoms into the residual amorphous matrix.

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Protection Method for Diameter-downsized Fiber Bragg Gratings for Highly Sensitive Ultraviolet Light Sensors

  • Seo, Gyeong-Seo;Ahn, Tae-Jung
    • Current Optics and Photonics
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    • 제2권3호
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    • pp.221-225
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    • 2018
  • We suggested the use of miniature hollow glass tubes having high ultraviolet (UV) transmission characteristics for the protection of optical-fiber-type UV sensors. We have recently proposed a highly sensitive optical sensor in the UV spectral range, using a fiber Bragg grating (FBG) coated with an azobenzene polymer as the photoresponsive material. In this study, we used UV-transparent miniature glass tubes to protect the etched FBG with the azobenzene polymer coating. This technique will be very useful for protecting various fiber-based UV sensors.

Real Time Spectroelectrochemical Experiments with a Multichannel Detector

  • Sun-Il Mho;Sally N. Holer;Bum-Soo Kim;Su-Moon Park
    • Bulletin of the Korean Chemical Society
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    • 제15권9호
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    • pp.739-743
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    • 1994
  • A spectroelectrochemical system assembled with a white light source, bifurcated optical fiber, Oriel Multispec spectrograph, and a charge-coupled device (CCD) detector is described. The system is shown to be capable of acquiring a whole spectrum in the spectral range of 290-800 nm in 25 ms or a longer period during electrochemical experiments at reflective working electrodes such as platinum or mercury. The utility of the system in studying electrochemical reactions during the potential scan, galvanostatic electrolysis, or after the potential step is demonstrated.