• Title/Summary/Keyword: Infrared Reflection

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High Resolution Near Infrared Spectrum of NGC 7023

  • Le, Huynh Anh N.;Pak, Soojong;Lee, Hye-In;Lee, Jae-Joon;Nguyen-Luong, Quang;Kaplan, Kyle;Jaffe, Daniel T.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.93.1-93.1
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    • 2014
  • The reflection nebula NGC 7023 is a typical example of a photodissociation region (PDR), which consists of high density molecular gas that is exposed to an intense UV radiation field. The source of the UV photons in NGC 7023 is the young pre-main-sequence Be star HD 200755. We present our near-infrared high-resolution (R ~ 40,000) spectrum of NGC 7023, covering a region of $1{\times}15$ arcseconds, observed during the commissioning runs of IGRINS (Immersion GRating near-INfrared Spectrometer). The spectrum shows many strong narrow emission lines that arise from the molecular rovibrational transitions of H2. From the intensity ratios between these H2 lines, we investigate physical conditions within the PDR such as the temperature, density, and pressure. The high spectral resolution of IGRINS allows us to resolve the velocity field of the PDR. In addition, we compare the IGRINS spectrum to Cloudy PDR model.

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Study on the Defects Detection in Composites by Using Optical Position and Infrared Thermography

  • Kwon, Koo-Ahn;Park, Hee-Sang;Choi, Man-Yong;Park, Jeong-Hak;Choi, Won Jae
    • Journal of the Korean Society for Nondestructive Testing
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    • v.36 no.2
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    • pp.130-137
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    • 2016
  • Non-destructive testing methods for composite materials (e.g., carbon fiber-reinforced and glass fiber-reinforced plastic) have been widely used to detect damage in the overall industry. This study detects defects using optical infrared thermography. The transient heat transport in a solid body is characterized by two dynamic quantities, namely, thermal diffusivity and thermal effusivity. The first quantity describes the speed with thermal energy diffuses through a material, whereas the second one represents a type of thermal inertia. The defect detection rate is increased by utilizing a lock-in method and performing a comparison of the defect detection rates. The comparison is conducted by dividing the irradiation method into reflection and transmission methods and the irradiation time into 50 mHz and 100 mHz. The experimental results show that detecting defects at 50 mHz is easy using the transmission method. This result implies that low-frequency thermal waves penetrate a material deeper than the high-frequency waves.

Quantification of Naproxen in Pharmaceutical Formulation using Near-Infrared Spectrometry (근적외 분광분석법을 이용한 나프록센 정제의 정량분석)

  • Kim Do Hyung;Woo Young Ah;Kim Hyo Jin
    • YAKHAK HOEJI
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    • v.49 no.1
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    • pp.1-5
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    • 2005
  • Near-infrared (NIR) spectroscopy has been widely applied in various field, since it is nondestructive and no sample preparation is required. In this paper, NIR spectroscopy was used for the determination of naproxen in a commercial pharmaceutical preparation. NIR spectroscopy was used to determine the content of naproxen in intact naproxen tablets containing 250 mg ($65.8\%$ nominal concentration) by collecting NIR spectra in the range of $1100{\sim}1750nm$. The laboratory-made samples had $46.1{\sim}85.5\%$ nominal naproxen concentration. The measurements were made by reflection using a fiber-optic probe and calibration was carried out by partial least square regression (PLSR). Model validation was performed by randomly splitting the data set into calibration and validation data set (63 samples as a calibration data set and 42 samples as a validation data set). The developed NIR calibration gave results comparable to the known values of tablets in a laboratorial manufacturing process with standard error of calibration (SEC) and standard error of prediction (SEP) of $1.06\%\;and\;1.04\%$, respectively. The NIR method showed good accuracy and repeatability. NIR spectroscopic determination in intact tablets allowed the potential use of real time monitoring for a running production process.

Phantom Glucose Measurement by Near Infrared Reflection (근적외선 반사를 이용한 인체 팬텀의 글루코즈 농도 측정)

  • 전계진;황인덕;조혜민;한상준;윤길원
    • Proceedings of the Optical Society of Korea Conference
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    • 2002.07a
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    • pp.250-251
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    • 2002
  • 혈당의 비침습적인 측정의 필요성은 잦은 채혈로 인한 감염의 우려, 필요할 때마다 채혈의 고통 없이 혈당을 측정할 수 있다는 장점 때문에 지난 20여 년 동안 활발히 연구되어 왔다. 근적외선 및 원적외선 흡수분광법, 라만분광법, Polarization rotation 또는 Stimulated Raman 측정법, 온도측정법, 통계적 분석법, 전처리연구 등 많은 분야에서 접근하고 있지만 아직까지는 in vivo 측정에 성공하고 있지 못하고 있다 [1]. (중략)

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Quantitative Measurement of Spray Deposit Using Spectrophotometer (Spectrophotometer를 이용한 농약의 부착량 측정방법)

  • 이중용;안성용;정창주
    • Journal of Biosystems Engineering
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    • v.24 no.6
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    • pp.479-486
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    • 1999
  • A measurement method for the deposition amount of spray, using tracer and spectrophotometer was developed. Food colors was selected as tracer, because it was cheep and easily treatable. Using NIRS(Near Infrared Reflection Spectrophotometer), regression curves between absorbance spectrum and concentration of the tracer were obtained. Yellow food colors showed the peak of spectrum at 452nm, and absorbance of peak showed a tendency to increase as concentration increased. Also, the possibility of concentration control by heating was investigated.

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Velocity Characteristics of Horizontal Saccadic Eye Movement (수평 Saccadic 안구운동의 속도 특성에 관한 연구)

  • 박상희;이상효
    • Journal of Biomedical Engineering Research
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    • v.3 no.1
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    • pp.17-22
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    • 1982
  • In this paper, peak velocity characteristics of saccadic eye movements were measured and analyzed as a velocity characteristics of horizontal saccadic eye movement system. Measurements were made with an infrared reflection method, and horizontal saccadic eye movements of 5 normal subject were recorded for the periodic and random pulse targets of 5$^{\circ}$, 10$^{\circ}$, 20$^{\circ}$ , and 30$^{\circ}$ amplitudes.

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Implementation of new gestures on the Multi-touch table

  • Park, Sang Bong;Kim, Beom jin
    • International Journal of Advanced Culture Technology
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    • v.1 no.1
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    • pp.15-18
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    • 2013
  • This paper describes new gestures on the Multi-touch table. The 2 new gestures with 3 fingers are used for minimizing of all windows that is already open and converting Aero mode. We also implement a FTIR (Frustrated Total Internal Reflection) Multi-touch table that consists of sheet of acrylic, infrared LEDs, camera and rear projector. The operation of proposed gestures is verified on the implemented Multi-touch table.

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Using ASTER TIR imagery to identify Heat Islands: A case study of New Jersey (ASTER 열적외선 이미지를 이용한 열섬 현상 탐지: 뉴저지를 사례로)

  • Park, Gwang yong;David W. Gwynn;David A. Robinson
    • Proceedings of the KGS Conference
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    • 2004.05a
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    • pp.56-56
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    • 2004
  • The ability to detect urban heat islands in satellite imagery is a function of spatial, spectral, and temporal resolutions. Imagery from the satellite-mounted Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor acquired since December 1999 allows us to view the Earth at a higher spectral resolution in the thermal infrared (TIR) portion of the electromagnetic spectrum than most other satellite systems (e.g., AVHRR, Landsat TM). (omitted)

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A Rapid Quantitative Assay of Intact Ambroxol Tablets by FT-NIR Spectroscopy

  • Kim, Do-Hyung;Ah, Woo-Young;Kim, Hyo-Jin
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.213.2-213.2
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    • 2003
  • A simple analytical procedure using FT-NIR for the rapid determination of individual ingredients was evaluated. Direct measurements were made by reflection using a reflectance accessory, by transmittance using tablet accessory and turn table. FT-NIR spectral data were transformed to the first derivative. Partial Least Square Regression(PLSR) was applied to quantify near-infrared (NIR) spectra of 2 ingredients. These calibration models were cross-validated (leave-one-out approach). The prediction ability of the models was evaluated on ambroxol tablets and compared with the real values in manufacturing procedure. (omitted)

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