• Title/Summary/Keyword: near-infrared image

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Medical Applications of Near Infrared Spectroscopy and Diffuse Optical Imaging (Review) (근적외선 분광법 및 확산 광 영상법의 최근 연구 동향)

  • Lee, Seung-Duk;Kwon, Ki-Won;Koh, Dal-Kwon;Kim, Beop-Min
    • Journal of Biomedical Engineering Research
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    • v.29 no.2
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    • pp.89-98
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    • 2008
  • NIRS (Near-infrared Spectroscopy) and DOI (Diffuse Optical Imaging) are relatively new, non-invasive, and non-ionizing methods that measure or image optical properties (Scattering and Absorption Coefficient) and physiological properties (Water Fraction, concentration of Oxy-, Deoxy-Hemoglobin, Cytochrome Oxidase, etc) of biological tissues. In this paper, three different types of NIRS systems, mathematical modeling, and reconstruction algorithms are described. Also, recent applications such as functional brain imaging, optical mammography, NIRS based BMI (Brain-Machine Interface), and small animal study are reviewed.

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.

Infrared Target Extraction Using Weighted Information Entropy and Adaptive Opening Filter

  • Bae, Tae Wuk;Kim, Hwi Gang;Kim, Young Choon;Ahn, Sang Ho
    • ETRI Journal
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    • v.37 no.5
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    • pp.1023-1031
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    • 2015
  • In infrared (IR) images, near targets have a transient distribution at the boundary region, as opposed to a steady one at the inner region. Based on this fact, this paper proposes a novel IR target extraction method that uses both a weighted information entropy (WIE) and an adaptive opening filter to extract near finely shaped targets in IR images. Firstly, the boundary region of a target is detected using a local variance WIE of an original image. Next, a coarse target region is estimated via a labeling process used on the boundary region of the target. From the estimated coarse target region, a fine target shape is extracted by means of an opening filter having an adaptive structure element. The size of the structure element is decided in accordance with the width information of the target boundary and mean WIE values of windows of varying size. Our experimental results show that the proposed method obtains a better extraction performance than existing algorithms.

Damage Analysis of CCD Image Sensor Irradiated by Continuous Wave Laser (연속발진 레이저에 의한 CCD 영상센서의 손상 분석)

  • Yoon, Sunghee;Jhang, Kyung-Young;Shin, Wan-Soon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.6
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    • pp.690-697
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    • 2016
  • EOIS(electro-optical imaging system) is the main target of the laser weapon. Specially, the image sensor will be vulnerable because EOIS focuses the incident laser beam onto the image sensor. Accordingly, the laser-induced damage of the image sensor needs to be identified for the counter-measure against the laser attack. In this study, the laser-induced damage of the CCD image sensor irradiated by the CW(continuous wave) NIR(near infrared) laser was experimentally investigated and mechanisms of those damage occurrences were analyzed. In the experiment, the near infrared CW fiber laser was used as a laser source. As the fluence, which is the product of the irradiance and the irradiation time, increased, the permanent damages such as discoloration and breakdown appeared sequentially. The discoloration occurred when the color filter was damaged and then the breakdown occurred when the photodiode and substrate were damaged. From the experimental results, LIDTs(laser-induced damage thresholds) of damages were roughly determined.

Topography in intertidal zone by satellite images

  • Kang, Yong-Q.
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.664-669
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    • 2002
  • Intertidal zone (tidal flat) is a place which is sometimes dry and sometimes wet depending on the tidal rhythm. Direct measurement of topography in the intertidal zone is very difficult to be achieved. The interface between wet and dry parts in the tidal flat, which can be identified from near infrared band of satellite image, is a 'depth contour' which corresponds to the sea level at the time of satellite pass. Aquisition of topography data in tidal flat is possible by combining various techniques such as (1) identification of the interface between wet and dry parts, (2) GCP correction of satellite image, and (3) realtime prediction of sea level elevation at the time of satellite pass. The algorithm was successfully applied in obtaining topography (bathymetry) data in the intertidal zone of Asan Bay in the west coast of Korea from 26 satellite images. The method is expected to be very efficient in making bathymetry data base in the western and southern parts of Korea where tidal flats are well developed in wide regions.

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Research on the efficient illumination method in iris recognition at a distance (원거리 홍채 인식에서 효율적 조명 조사방법에 관한 연구)

  • Jo, Hyun-Su;Bae, Kwang-Hyuk;Park, Kang-Ryoung;Kim, Jai-Hie
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.969-970
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    • 2008
  • This paper proposes illumination-efficient iris image capturing method. face capture method for extraction of iris pattern with one high resolution camera needs a large scale near infrared illumination. we replace high-resolution camera with co-optic-axial combination between wide view camera and narrow view camera. because this method needs small scale illumination that illuminate only narrow camera viewing angle, we can capture iris pattern image with small scale near infrared illumination.

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Synthesis and Characterization of Quaterrylene Bisimide as NIR Colorant (NIR Colorant용 Quaterrylene Bisimide의 합성 및 특성 연구)

  • Park, Keun-Soo;Jeong, Yeon-Tae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.5
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    • pp.398-403
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    • 2011
  • Recently, Near-infrared (NIR)colorant is intriguing and attractive but full of challenges. Although some cyanine colorant have been commercialized, near-infrared colorant with intensive NIR absorption, good chemical and photo-stability, and high solubility still remain as target compound. Certain polycyclic aromatic compounds such as quaterrylene represent a key class of NIR colorant and also give rise to outstanding physical and chemical properties after appropriate chemical modification. In this study, We have tried to introduceimide functional group to quaterrylene in order to give chemical and thermal stability. Finally, N,N'-bis (2,6-diisopropylphenyl)-quarterrylene-3,4:13,14-tetracarboximide was synthesized and evaluated its properties using $^1H$ NMR, Maldi-tof, TGA, and UV/VIS/NIR spectroscopy as NIR colorant. The quaterrylene bisimide compound exhibit a excellent thermal stability and chemical stability.

Near-Field Imaging of Graphene

  • Gwon, Hyeok-Sang;Kim, Deok-Su;Kim, Ji-Hwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.127-127
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    • 2012
  • We carried out the high-resolution dielectric mapping of graphenes on $SiO_2$/Si substrate, using the scattering Apertureless Near-Field Scanning Optical Microscopy (s-ANSOM) in both visible (633 nm) and infrared (3.6 um) wavelengths. In the visible wavelength, the dielectric contrasts are almost proportional to the number of the graphene layers, which indicates that the near-field interaction between the tip and individual graphene layers leads to an image charge oscillation in two-dimension. In the infrared region, on the other hand, we observe unique layer-specific contrasts that do not linearly increase with number of layers. It is attributed to the layer-dependent band- structure of graphenes.

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Color Noise Detection and Image Restoration for Low Illumination Environment (저조도 환경 기반 색상 잡음 검출 및 영상 복원)

  • Oh, Gyoheak;Lee, Jaelin;Jeon, Byeungwoo
    • Journal of Broadcast Engineering
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    • v.26 no.1
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    • pp.88-98
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    • 2021
  • Recently, the crime prevention and culprit identification even in a low illuminated environment by CCTV is becoming ever more important. In a low lighting situation, CCTV applications capture images under infrared lighting since it is unobtrusive to human eye. Although the infrared lighting leads to advantage of capturing an image with abundant fine texture information, it is hard to capture the color information which is very essential in identifying certain objects or persons in CCTV images. In this paper, we propose a method to acquire color information through DCGAN from an image captured by CCTV in a low lighting environment with infrared lighting and a method to remove color noise in the acquired color image.

Damage Degree Valuation of Forest Using NDVI from Near Infrared CCD Camera and Spectral Radiometer in a Forest Fire Area (근적외 CCD카메라와 분광반사계의 식생지수를 이용한 산불 발생지역에서의 산림 피해도 평가)

  • Choi, Seung-Pil;Kim, Dong-Hee;Park, Jong-Sun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.4
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    • pp.367-374
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    • 2005
  • Recently, forest damage has occurred often and made big issues. Among them, the damage by forest fire is not only damage of itself but also being connected with secondary damage like a flood. This is the fact that a forest fire is caused rather artificially by people than nature. In this study, we try to investigate damage of a forest fire through spectral reflectance of a plant community surveyed using a near infrared CCD camera and a SPM (Spectral Radiometer) as advanced work to use satellite image data. That is, damage of a forest fire by the naked eye observation was divided into the No damage, the light damage, the serious damage and we estimated activity of forest and grasped revival possibility of forest. Through correlation analysis between the spectral reflectance by SPM and the near infrared CCD camera, we could get high correlation in the No damage and light damage. Therefore, when we surveyed damage of a forest fire, we could grasp damage, that is hardly observed by the naked eye by, using jointly the spectral radiometer and the near infrared CCD camera.