• Title/Summary/Keyword: NIR filter

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Frequency Domain Methods for Demosaicking of Single-Chip RGB/NIR Image Sensors

  • Jeong, Kil-Hyun
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.11
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    • pp.25-30
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    • 2017
  • In this paper, We proposed an effective demosaicking method for single chip RGB-NIR sensors to recover RGB and NIR images. As the method operates in the spatial frequency domain, the frequency domain characteristics of the sampled CFA data are investigated. Using the luminance signal in the frequency domain and the chrominance signals are processed separately with different filters. The simulated images using the real images are compared with other state-of-art methods. As a result, the proposed demosaicking method resulted an effective calculation by a single processing which the existing alternating projection method requires repeated calculation.

Transparent Near-infrared Absorbing Dyes and Applications (투명 근적외선 흡수 염료 및 응용 분야)

  • Hyocheol Jung;Ji-Eun Jeong;Sang-Ho Lee;Jin Chul Kim;Young Il Park
    • Applied Chemistry for Engineering
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    • v.34 no.3
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    • pp.207-212
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    • 2023
  • Near-infrared (NIR) absorbing dyes have been applied to various applications such as optical filters, biotechnology, energy storage and conversion, coating additive, and traditionally information-storage materials. Because image sensors used in cellphones and digital cameras have sensitivity in the NIR region, the NIR cut-off filter is essential to achieving more clear images. As energy storage and conversion have been important, diverse NIR absorbing materials have been developed to extend the absorption region to the NIR region, and NIR absorbing materials-based research has proceeded to improve device performances. Adding NIR-absorbing dye with a photo-thermal effect to a self-healable coating system has been attractive for future mobility technology, and more effective self-healing properties have been reported. In this report, the chemical structures of representative NIR-absorbing dyes and state of the art research based on NIR-absorbing dyes are introduced.

NIR DIODE ARRAY SPECTROMETERS ON AGRICULTURAL HARVEST MACHINES OVERVIEW AND OUTLOOK

  • Rode, Michael
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1172-1172
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    • 2001
  • Compact Near Infrared Diode Array Spectrometers offer new possibilities for on line quality assurance in the agricultural sector. Due to their speed and complete robustness towards temperature fluctuations and mechanical shock Diode Array Spectrometers are suitable for the use on Agricultural Harvest Machines. The growing consumer consciousness of food quality in combination with falling manufacturing prices demands procedures for an effective quality control system. The various conventional types of NIR instruments which have so far been used in laboratories are unsuitable for mobile applications under the rough conditions of field cropping not only because of their slow speed of measurement but also because of their shock sensitive filter wheels and monochromators necessary for fractionating polychromatic light. Another advantage of the on line use is the reduction of the sampling error because of the continuously measurement of the whole product. Considering the large economic importance of the dry matter content on agricultural products it is of particular advantage that water belongs to those constituents which are most easily assessed in the near infrared. While other constituents of economic importance such as starch, oil and protein in grains and seeds have a much lesser effect on NIR signals, their contents can nonetheless be assessed with high analytical precision on freshly harvested grains and seeds. In the last years several applications for on line quality assessment on harvesting machines were developed and tested. The talk will give an overview and outlook on existing and future possibilities of this new field of NIR applications.

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Identification of geographical origin of sesame seeds by near infrared spectroscopy (근적외 분석법에 의한 참깨의 원산지 판별)

  • Kwon, Young-Kil;Cho, Rae-Kwang
    • Applied Biological Chemistry
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    • v.41 no.3
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    • pp.240-246
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    • 1998
  • Geographical origin of the Korean, Chinese and Japanese sesame seeds were identified very high accuracy by NIR spectroscopy. The NIR instrument of filter type showed the same accuracy of the monochromator scanning type to identify the geographical origin of the sesame seeds. In case of adulteration between the Korean and Chinese sesame seeds, the ratio of addition could be determined about 10% error level. The reason of identification of geographical origin by NIR spectroscopy, it was supposed to the difference, of oil cake substance.

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Characterization of Denitrifier Community in Independent Anoxic Reactor Using Modified BAF Process (Modified BAF 공정을 이용한 독립적인 무산소조에서 탈질미생물 군집의 특성)

  • Park, Jeung-Jin;Jeung, Young-Rok;Yu, Jae-Cheul;Hur, Sung-Ho;Choi, Won-Seok;Byun, Im-Gyu;Lee, Tae-Ho;Park, Tae-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.7
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    • pp.752-756
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    • 2006
  • The independent anoxic reactor was introduced in biological aerated filters as the regulation of water quality requirement, especially total nitrogen, had been strengthened. The process studied in this work was upflow $Biobead^{(R)}$ process which was used commercial invented for removal of organic materials and nitrification. For the purpose of evaluating the independent anoxic reactor, PCR-DGGE, of the molecular biological methods, was performed. Two types of nitrite reductase genes were selected. One is nirS represented cytocrome $cd_1$ nitrite reductase gene and the other is nirK represented Cu-containing nitrite reductase gene. Denitrifier community in the independent anoxic reactor was analyzed with PCR-DGGE using these two denitrifying functional genes. As the result of the PCR, only nirS gene was detected between nirS and nirK. With the result of the DGGE, specific bands became strong, as the operating days were longer, nitrate loading rate was increased. otherwise those of the initial activated sludge showed various bands. In the consequence of the sequence of DGGE bands, various denitrifiers were sequenced in the initial activated sludge, while specific denitrifiers like alcaligenes faecalis were predominant in the anoxic reactor. Consequently, introduction of the independent anoxic reactor made it possible to achieve 96% denitrification efficiency, and was proper for the modification of BAF process.

ROI Extraction and Enhancement for Finger Vein Recognition (지정맥 인식을 위한 ROI 검출과 정맥 증강처리)

  • Lee, Ju-Won;Lee, Byeong-Ro
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.4
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    • pp.948-953
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    • 2015
  • Recently, the finger vein recognition based on NIR and CCD sensor camera is investigating the technology to identify a personal using by biometrics. The performance difference of finger vein recognition is generated according to methods that are to separate the vein and background from noises such as finger thickness, ambient light, skin temperature, etc. To improve these problems, in this study, we are proposing the methods for rotation, ROI extraction, and enhancement of vein image captured by NIR LED and CCD camera, and were evaluated performances of these methods. In results of the experiment, the accuracy of the proposed method for image rotation and ROI extraction was 99.8%. And the proposed filter bank method in vein enhancement has shown better performance than retinex algorithm. The proposed method for results of these experimentations will provide better recognition rate when applied to the preprocessing of finger vein recognition.

NORTH ECLIPTIC POLE WIDE SURVEY

  • Lee, Hyung Mok;Kim, Seong Jin;NEP-Wide Team, NEP-Wide Team
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.129-134
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    • 2012
  • The North Ecliptic Pole (NEP) Wide survey covered about 5.4 $deg^2$, a nearly circular area centered on the NEP, using nine passbands of InfraRed Camera (IRC). We present the photometric properties of the data sets, and the nature of the sources detected in this field. The number of detected sources varied according to the filter band: with about 109,000 sources in the NIR, about 20,000 sources in the MIR-S, and about 16,000 sources seen in the MIR-L channel. The $5{\sigma}$ detection limits are about 21 mag in the NIR and 19.5 - 18.5 mag in the MIR bands in terms of the AB magnitude. 50% completeness levels are about 19.8 mag at $3{\mu}m$, 18.6 mag at $9{\mu}m$, and 18 mag at $18{\mu}m$ band (in AB magnitude), respectively. In order to validate the detected sources, all of them are confirmed by matching tests with those in other bands. The 'star-like' sources, defined by the high stellarity and magnitude cut from the optical ancillary data, appear statistically to have a high probability of being stars. The nature of the various types of extragalactic sources in this field are discussed using the color-color diagrams of the NIR and MIR bands with the redshift tracks of galaxies providing useful guidelines.

Near Infrared Shielding Properties of Quaternary Tungsten Bronze Nanoparticle Na0.11Cs0.22WO3

  • Moon, Kyunghwan;Cho, Jin-Ju;Lee, Ye-Bin;Yoo, Pil J.;Bark, Chung Wung;Park, Juhyun
    • Bulletin of the Korean Chemical Society
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    • v.34 no.3
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    • pp.731-734
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    • 2013
  • Reduced tungsten bronze nanoparticles of ternary and quaternary compounds were prepared by adding sodium and cesium to crystal structures of tungsten trioxides ($Na_xCs_{0.33-x}WO_3$, x = 0, 0.11) while maintaining the overall alkali metal fraction at 0.33, in an attempt to control near infrared (NIR) shielding property in the particular wavelength range of 780 to 1200 nm. The structure and composition analysis of the quaternary compound, $Na_{0.11}Cs_{0.22}WO_3$, revealed that 93.1% of the hexagonal phase was formed, suggesting that both alkali metals were mainly inserted in hexagonal channel. The NIR shielding property for $Na_{0.11}Cs_{0.22}WO_3$ was remarkable, as this material demonstrated efficient transmittance of visible light up to 780 nm and enhancement in NIR shielding because of the blue-shifted absorption maximum in comparison to $Cs_{0.33}WO_3$.

Near-infrared Spectroscopy of Metal-enriched Supernova Ejecta in Cassiopeia A

  • Lee, Yong-Hyun;Koo, Bon-Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.44.4-44.4
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    • 2019
  • The supernova remnant Cassiopeia A (Cas A) provides a unique opportunity to observe the fine details of the explosion of core-collapse supernova (SN). Previous optical and near-infrared (NIR) observations of Cas A have shown that the spatial distribution of the metal-enriched SN ejecta is very complicated, indicating that the SN explosion should have been asymmetric and turbulent, especially near the core. Recently, we obtained a long-exposure (~10 hr) image of Cas A by using the UKIRT 3.6-m telescope with a narrow-band filter centered at [Fe II] 1.644 um emission. This 'deep [Fe II] image' provides an unprecedented panoramic view of Cas A, revealing the distribution of dense SN ejecta over the entire remnant. We have carried out NIR multi-object spectroscopic observations of the dense ejecta knots in the northeastern (NE) and eastern (E) outer regions of the remnant using the MMIRS attached on the MMT 6.5-m telescope. A total of 67 ejecta knots are detected. By analyzing their spectra, we have found that the knots in the NE area show strong [S II]/[S III] and [Fe II] lines but little or no [P II] line, while those in the E outer region show strong [Fe II] lines but weak [S II]/[S III] lines. In this talk, we present the preliminary results of our NIR spectroscopic observations and discuss the implications.

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A Study for Automatic Analysis of Qualysis of Quality Components in Tabacco Leaves Using Non-destructive Analytical Method (근적외 분광분석법에 의한 잎담배의 품질측정 자동화)

  • Cho, Rae-Kwang;Lee, Kyung-Hee;Lee, Jung-Hwan;Kwon, Yong-Kil
    • Applied Biological Chemistry
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    • v.37 no.5
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    • pp.349-355
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    • 1994
  • The present study was conducted to develop the automatic analytical method for determining moisture, nicotine, reducing sugar and total nitrogen contents and color(L, a, b) value in domestic tobacco leaves using near infrared(NIR) spectroscopy. The results of multiple linear regression analysis between chemical and NIR data showed that NIR spectro-scopy can determine those quality components of tobacco samples in 30 seconds, non-destructively. The results using developed calibrations are summarized as follows; The standard error of prediction(SEP) for moisture, nicotine. total nitrogen, reducing sugar contents and color(L, a, b) value in domestic tobacco leaves was 0.28%, 0.25%, 0.07%, 0.75%, 1.25, 0.44 and 1.07, respectively. In addition, The possibility of developing the cheaper filter type NIR instrument, for quality evaluation in the procurement from leaf tobacco cultivators and process control was investigated.

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