• Title/Summary/Keyword: Near-Infrared

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NEAR-INFRARED WIDE-FIELD IMAGING CAMERA WITH PtSi 1040 $\times$ 1040 CSD

  • ITOH NOBUNARI;YANAGISAWA KENSHI;ICHIKAWA TAKASHI
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.379-380
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    • 1996
  • We have constructed a near-infrared imaging camera which is attached to the prime focus of 105cm Schmidt telescope at Kiso Observatory. The camera is equipped with a 1040$\times$1040 PtSi CSD array developed by Mitsubishi Electric Co. The combination of Kiso Schmidt and the array gives a wide field of view of 18.4'$\times$18.4' with a reasonable spatial resolution of 1.06' /pixel. The system performances of the camera have been evaluated through laboratory and observational tests. Low noise, good cosmetics(no defect pixels), and good stability of the camera system show an excellent performance for astronomical use.

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Novel optical properties of amorphous ferric hydroxide in near infrared region

  • Kang, Tae Yeon;Chae, Weon-Sik
    • Rapid Communication in Photoscience
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    • v.4 no.2
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    • pp.34-36
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    • 2015
  • New spectroscopic characteristics of amorphous ferric hydroxide ($Fe(OH)_3$), interestingly in the near infrared (NIR) region, are presented in this study. The absorption spectrum of ferric hydroxide covers wide spectral regions from ultraviolet to NIR (200~900 nm). Unique emission bands were newly observed in the NIR regions (800~1400 nm). Several bands of this NIR emission are quiet well overlapped with the combinational vibrational absorption bands of water. From photothermal conversion study, very interestingly, temperature of aqueous mixture solution including the amorphous ferric hydroxide was significantly increased from ambient temperature to $38^{\circ}C$ for 30 minutes under irradiation of a standard helium lamp.

A Novel Image Dehazing Algorithm Based on Dual-tree Complex Wavelet Transform

  • Huang, Changxin;Li, Wei;Han, Songchen;Liang, Binbin;Cheng, Peng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.10
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    • pp.5039-5055
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    • 2018
  • The quality of natural outdoor images captured by visible camera sensors is usually degraded by the haze present in the atmosphere. In this paper, a fast image dehazing method based on visible image and near-infrared fusion is proposed. In the proposed method, a visible and a near-infrared (NIR) image of the same scene is fused based on the dual-tree complex wavelet transform (DT-CWT) to generate a dehazed color image. The color of the fusion image is regulated through haze concentration estimated by dark channel prior (DCP). The experiment results demonstrate that the proposed method outperforms the conventional dehazing methods and effectively solves the color distortion problem in the dehazing process.

Prediction of Chemical Compositions for On-line Quality Measurement of Red Pepper Powder Using Near Infrared Reflectance Spectroscopy (NIRS)

  • Lee, Sun-Mee;Kim, Su-Na;Park, Jae-Bok;Hwang, In-Kyeong
    • Food Science and Biotechnology
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    • v.14 no.2
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    • pp.280-285
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    • 2005
  • Applicability of near infrared reflectance spectroscopy (NIRS) was examined for quality control of red pepper powder in milling factories. Prediction of chemical composition was performed using modified partial least square (MPLS) techniques. Analysis of total 51 and 21 red pepper powder samples by conventional methods for calibration and validation, respectively, revealed standard error of prediction (SEP) and correlation coefficient ($R^2$) of moisture content, ASTA color value, capsaicinoid content, and total sugar content were 0.55 and 0.90, 8.58 and 0.96, 31.60 and 0.65, and 1.82 and 0.86, respectively; SEP and $R^2$ were low and high, respectively, except for capsaicinoid content. The results indicate, with slight improvement, on-line quality measurement of red pepper powder with NIRS could be applied in red pepper milling factories.

2MASS Near-Infrared Photometry of the Old Open Cluster Trumpler 5

  • Kim, Sang-Chul;Kyeong, Jae-Mann;Sung, Eon-Chang
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.53.2-53.2
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    • 2010
  • Using the JHK 2MASS near-infrared data, we present photometry results for the old open cluster (OC) Trumpler 5 (Tr 5). From the near-infrared color-magnitude diagrams of Tr 5, we have located the position of the red giant clump (RGC) stars, and used the mean magnitude of the RGC stars in K-band to estimate the distance to Tr 5. From the Padova isochrone fittings, we have estimated the reddening, metallicity, and age of Tr 5. These parameters generally agree well with those obtained from the previous studies on Tr 5 and confirms that this cluster is an old OC with metallicity being metal-poorer than solar abundance, located in the anti-Galactic center region.

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Food Powder Classification Using a Portable Visible-Near-Infrared Spectrometer

  • You, Hanjong;Kim, Youngsik;Lee, Jae-Hyung;Jang, Byung-Jun;Choi, Sunwoong
    • Journal of electromagnetic engineering and science
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    • v.17 no.4
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    • pp.186-190
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    • 2017
  • Visible-near-infrared (VIS-NIR) spectroscopy is a fast and non-destructive method for analyzing materials. However, most commercial VIS-NIR spectrometers are inappropriate for use in various locations such as in homes or offices because of their size and cost. In this paper, we classified eight food powders using a portable VIS-NIR spectrometer with a wavelength range of 450-1,000 nm. We developed three machine learning models using the spectral data for the eight food powders. The proposed three machine learning models (random forest, k-nearest neighbors, and support vector machine) achieved an accuracy of 87%, 98%, and 100%, respectively. Our experimental results showed that the support vector machine model is the most suitable for classifying non-linear spectral data. We demonstrated the potential of material analysis using a portable VIS-NIR spectrometer.

An Vision System for Automatic Detection of Vehicle Passenger (차량 승객 자동탐지를 위한 비젼시스템)

  • Lee Young-Sik;Bae Cheol-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.3
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    • pp.622-626
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    • 2005
  • This paper presents an active vision system for ITS(intelligent transportation system : ITS). We have described a novel method to provide high quality imaging signals to a system that will perform passenger detection and counting in the roadway. The method calls for two co-registered near-infrared cameras with spectral sensitivity above (upper-band) and below (lower-band) the quality of the signal remains. We propose a novel system based on fusion of near-infrared imaging signals and we demonstrate its adequacy with theoretical and experimental arguments.

Cure Kinetics for the Acid Anhydride-cured Epoxy System Using a Near-infrared Reflection Spectroscopy (근적외선 분광분석을 통한 산무수물경화 에폭시 시스템의 경화 동력학)

  • 곽근호;박수진;이재락
    • Polymer(Korea)
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    • v.24 no.1
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    • pp.65-71
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    • 2000
  • The latent properties and cure kinetics of an acid anhydride-cured epoxy resin have been investigated by a near-infrared (NIR) reflection spectroscopy. The assignments of the latent properties and cure behaviors were performed by the measurements of the NIR reflectance for epoxide and hydroxyl groups at different temperatures. A comprehensive analysis of the origin, location, and shifts during reaction of all major NIR absorption peaks in the spectral range from 4000 to 7100 $cm^{-1}$ / was provided. The extent of reaction was determined from NIR absorption band at the 4530 $cm^{-1}$ / depending on epoxide concentration and cure temperature.

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Nondestructive Classification between Normal and Artificially Aged Corn (Zea mays L.) Seeds Using Near Infrared Spectroscopy

  • Min, Tai-Gi;Kang, Woo-Sik
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.53 no.3
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    • pp.314-319
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    • 2008
  • Near infrared (NIR) spectroscopy was used to classify normal and artificially aged nonviable corn (Zea mays L., cv. 'Suwon19') seeds. The spectra at 1100-2500nm were scanned with normal and artificially aged single seeds and analyzed by principle component analysis (PCA). To discriminate normal seeds from artificially aged seeds, a calibration modeling set was developed with a discriminant partial least square 2 (PLS 2) method. The calibration model derived from PLS 2 resulted in 100% classification accuracy of normal and artificially aged (aged) seeds from the raw, the 1st and 2nd derivative spectra. The prediction accuracy of the unknown normal seeds was 88, 100 and 97% from the raw, the $1^{st}$ and $2^{nd}$ derivative spectra, and that of the unknown aged seeds was 100% from all the raw, the $1^{st}$ and $2^{nd}$ derivative spectra, respectively. The results showed a possibility to separate corn seeds into viable and non-viable using NIR spectroscopy.

Fisheye Lens for Image Processing Applications

  • Kweon, Gyeong-Il;Choi, Young-Ho;Laikin, Milton
    • Journal of the Optical Society of Korea
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    • v.12 no.2
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    • pp.79-87
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    • 2008
  • We have developed a miniature fisheye lens with $190^{\circ}$ field of view operating simultaneously in the visible and the near infrared wavelengths. The modulation transfer function characteristic for the visible wavelength is sufficient for a mega-pixel-grade image sensor. The lens also has a fair resolution in the infrared wavelength region. The calibrated $f-{\theta}$ distortion is less than 5%, and the relative illumination is over 90%. In consequence, a sharp wide-angle image can be obtained which is uniform in brightness over the entire range of field angles. The real image heights for the visible and the near infrared wavelengths have been fitted to polynomial functions of incidence angle with sub-pixel accuracies. Combined with the near equidistance projection scheme of the lens, this lens can be advantageously employed in various image-processing applications requiring a wide-angle lens.