• Title/Summary/Keyword: infrared detector

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Development of Infrared Telemeter for Autonomous Orchard Vehicle (과수원용 차량의 자율주행을 위한 적외선 측거 장치개발)

  • 장익주;김태한;이상민
    • Journal of Biosystems Engineering
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    • v.25 no.2
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    • pp.131-140
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    • 2000
  • Spraying operation is one of the most essential in an orchard management and it is also hazardous to human body. for automatic and unmanned spraying , an autonomous travelling vehicle is demanded. In this study, a telemeter was developed using infrared beam which could detect trunks and obstacles measure distance and direction from the vehicle travelling in the orchard. The telemeter system was composed of two infrared LED transmitters and receivers, a beam scanning device for continuous object detection , two rotary encoders for angle detector, and a beam level controller for uneven soil surface. The detected distance and direction signal s were sent to personal computer which made for the system display the angular and distance measurements through I/O board. According to a field test in an apple farm, the system detected up to 10m distance under 12 V of transmitted beam intensity, however, it was recommended that the proper beam transmit intensity be 7 v at the 10 m distance, because of the negative effect to human body at 12 V. The error rate of this system was 0.92 % when the actual distance was compared to measured one. The system was feasible at the small error rate. The developed telemeter system was an important part for autonomous travelling vehicle provided the real time object recognition . A direction control system could be constructed suing the system. It is expected that the system could greatly contribute to the development of autonomous farm vehicle.

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Research on Local and Global Infrared Image Pre-Processing Methods for Deep Learning Based Guided Weapon Target Detection

  • Jae-Yong Baek;Dae-Hyeon Park;Hyuk-Jin Shin;Yong-Sang Yoo;Deok-Woong Kim;Du-Hwan Hur;SeungHwan Bae;Jun-Ho Cheon;Seung-Hwan Bae
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.7
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    • pp.41-51
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    • 2024
  • In this paper, we explore the enhancement of target detection accuracy in the guided weapon using deep learning object detection on infrared (IR) images. Due to the characteristics of IR images being influenced by factors such as time and temperature, it's crucial to ensure a consistent representation of object features in various environments when training the model. A simple way to address this is by emphasizing the features of target objects and reducing noise within the infrared images through appropriate pre-processing techniques. However, in previous studies, there has not been sufficient discussion on pre-processing methods in learning deep learning models based on infrared images. In this paper, we aim to investigate the impact of image pre-processing techniques on infrared image-based training for object detection. To achieve this, we analyze the pre-processing results on infrared images that utilized global or local information from the video and the image. In addition, in order to confirm the impact of images converted by each pre-processing technique on object detector training, we learn the YOLOX target detector for images processed by various pre-processing methods and analyze them. In particular, the results of the experiments using the CLAHE (Contrast Limited Adaptive Histogram Equalization) shows the highest detection accuracy with a mean average precision (mAP) of 81.9%.

Evaluation of the Scar Treatment using Near Infrared Diffuse Reflectance Spectroscopy (근적외선 확산반사 분광법을 이용한 흉터치료 평가)

  • Jang, I.J.;Youn, Jong-In
    • Journal of Biomedical Engineering Research
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    • v.37 no.1
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    • pp.53-60
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    • 2016
  • Monitoring of dermal collagen is important to assess various scar conditions, and many diagnostic methods have been applied to quantify collagen contents in scar tissue. In this study, Monte Carlo simulation was used to evaluate diffuse reflectance distributions in scar condition by a near-infrared laser source. The results showed that the effective distance of the light source and the detector was 2 mm to monitor the various scar conditions using diffuse reflectance spectroscopy. This study may suggest to the optimal design for a near infrared diffuse reflectance spectroscopy during the scar treatment.

OKAYAMA ASTROPHYSICAL OBSERVATORY WIDE-FIELD CAMERA

  • YANAGISAWA KENSHI
    • Journal of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.109-112
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    • 2005
  • We present the design, expected performance, and current status of the wide field near-infrared camera (OAOWFC) now being developed at Okayama Astrophysical Observatory, NAOJ, NINS. OAOWFC is a near-infrared survey telescope whose effective aperture is 91cm. It works at Y, J, H, and $K_s$ bands and is dedicated to the survey of long period variable stars in the Galactic plane. The field of view is $0.95 {\times} 0.95 deg^2$ which is covered by one HAWAII-2 RG detector of 2048 ${\times}$ 2048 pixels with the pixel size of $18.5 {\mu}m\;{\times}\;18.5{\mu}m$, that results in the sampling pitch of 1.6 arcsec/pixel. OAOWFC can sweep the area of $840 deg^2$ every 3 weeks, attaining a limiting magnitude of 13 in $K_s$ band. It allows us to observe long period variables embedded in the Galactic plane where interstellar extinction is severe in optical.

Optical Property Measurements of Optical Phantoms and Honan Tissues Using Frequency-Domain Diffuse Optical Tomography (주파수 영역 확산광 단층촬영 장치를 이용한 광 팬텀 및 인체조직의 광 계수 측정)

  • Ho, Dong-Su;Kwon, Ki-Woon;Eom, Gi-Yun;Lee, Seung-Duk;Kim, Beop-Min
    • Journal of Biomedical Engineering Research
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    • v.28 no.2
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    • pp.229-234
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    • 2007
  • Diffuse optical tomography (DOT) is a relatively new medical imaging modality which uses near infrared light to image large-sized tissues noninvasively. We constructed a frequency-domain DOT system to measure the optical properties of optical phantoms and human tissues. The FD-DOT uses the intensity-modulated infrared light source that illuminates the biological tissues. The phase shift and modulation changes at each detector site are separately processed to measure the optical properties. The absorption and scattering coefficients are separately estimated using inverse algorithms.

Development of a portable near infrared device for skin moisture by using a microspectrometer

  • Woo, Young-Ah;Suh, Eun-jung;Ahn, Jhii-Weon;Kim, Hyo-Jin
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.203-224
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    • 2003
  • In recent years, a miniature spectrometer has been extensively developed due to the combination of fiber optics and semiconductor detector arrays. This type of miniature spectrometer has advantages of low price and robustness because of the capability of mass production and no moving parts are required such as lenses, mirrors and scanning monochromator. In this study, for skin diagnostics, a portable near infrared (NIR) system has been developed using a LlGA microspectrometer, which is photo-diode arrays-type.(omitted)

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Near-infrared photometric properties of red-supergiant stars in nearby galaxies : NGC 4214, NGC 4736, and NGC 5194 / NGC 5195

  • Jung, DooSeok;Chun, San-Hyun;Choudhury, Samyaday;Sohn, Young-Jong
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.62.1-62.1
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    • 2016
  • We study the near-infrared photometric properties of red-supergiant stars (RSGs) in three nearby galaxies located within 15 Mpc: NGC 4214, NGC 4736 and NGC 5194 / NGC 5195. The near-infrared (JHK) imaging data were obtained using the WFCAM detector mounted on UKIRT telescope in Hawaii. We used the DAOPHOT/ALLSTAR pacakge to carry out the photometry. We applied MARCS synthetic fluxes to estimate the effective temperatures and luminosities of the RSGs in all the three galaxies. The results were plotted in the Hertzsprung-Russell(H-R) diagram along with the theoretical evolutionary tracks with different masses. We explore the spatial correlation between the RSGs and H II regions by examing the H-R diagram of the RSGs in the dominant H II regions for each of these three galaxies.

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Non-invasive Blood Glucose Measurement by a Portable Near Infrared (NIR) System (휴대용 근적외선 분광분석기를 이용한 비침투 혈당 측정)

  • 강나루;우영아;차봉수;이현철;김효진
    • YAKHAK HOEJI
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    • v.46 no.5
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    • pp.331-336
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    • 2002
  • The purpose of this study is to develop a non-invasive blood glucose measurement method by a portable near infrared (NIR) system which was newly integrated by our lab. The portable NIR system includes a tungsten halogen lamp, a specialized reflectance fiber optic probe and a photo diode array type InGaAs detector; which was developed by a microchip technology based on the lithography. Reflectance NIR spectra of different parts of human body (finger tip, earlobe, and inner lip) were recorded by using a fiber optic probe. The spectra were collected over the spectral range 1100 ∼ 1740 nm. Partial least squares regression (PLSR) was applied for the calibration and validation for the determination of blood glucose. The calibration model from earlobe spectra presented better results, showing good correlation with a glucose oxidase method which is a mostly used standard method. This model predicted the glucose concentration for validation set with a SEP of 33 mg/dL. This study indicated the feasibility for non-invasive monitoring of blood glucose by a portable near infrared system.

Fourier Transform Infrared Matrix Isolation Study of Acetonitrile in Solid Argon

  • Hack Sung Kim;Kwan Kim
    • Bulletin of the Korean Chemical Society
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    • v.13 no.5
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    • pp.520-526
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    • 1992
  • The intramolecular fundamental vibrations of $CH_3CN$ trapped in solid argon matrix have been reinvestigated by means of FT-IR spectroscopy in the spectral range of 4000-500 $cm^{-1}$. By employing a quantum detector, infrared spectra could be obtained at matrix to solute ratio of 10000, allowing the clarification of the peaks due to monomeric species more clearly. Temperature controlled diffusion was initiated to identify the dimeric and polymeric species in terms of difference spectra. The assignments of monomeric and dimeric species are found, in general, to agree with the earlier work performed at higher concentration (Ar/$CH_3CN$ = 1500) using a dispersive spectrometer. Nonetheless the difficulty of minute differences between the earlier infrared and Raman spectroscopic results could be resolved. Moreover, the previously unnotified peaks due to polymeric species have been identified.

Fabrication and Device Characteristics of Infrared Photodetector Based on InAs/GaSb Strained-Layer Superlattice (InAs/GaSb 응력초격자를 이용한 적외선검출소자의 제작 및 특성 연구)

  • Kim, J.O.;Shin, H.W.;Choe, J.W.;Lee, S.J.;Kim, C.S.;Noh, S.K.
    • Journal of the Korean Vacuum Society
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    • v.18 no.2
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    • pp.108-115
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    • 2009
  • The superlattice infrared photodetector (SLIP) with an active layer of 8/8-ML InAs/GaSb type-II strained-layer superlattice (SLS) of 150 periods was grown by MBE technique, and the proto-type discrete device was defined with an aperture of $200-{\mu}m$ diameter. The contrast profile of the transmission electron microscope (TEM) image and the satellite peak in the x-ray diffraction (XRD) rocking curve show that the SLS active layer keeps abrupt interfaces with a uniform thickness and a periodic strain. The wavelength and the bias-voltage dependences of responsivity (R) and detectivity ($D^*$) measured by a blackbody radiation source give that the cutoff wavelength is ${\sim}5{\mu}m$, and the maximum Rand $D^*$ ($\lambda=3.25{\mu}m$) are ${\sim}10^3mA/W$ (-0.6 V/13 K) and ${\sim}10^9cm.Hz^{1/2}/W$ (0 V/13 K), respectively. The activation energy of 275 meV analyzed from the temperature dependent responsivity is in good agreement with the energy difference between two SLS subblevels of conduction and valence bands (HH1-C) involving in the photoresponse process.