• Title/Summary/Keyword: Infrared Channel

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Performance of a DS/CDMA Packet Network in an Indoor Wireless Infrared Channel

  • Kim, Jin-Young
    • Proceedings of the IEEK Conference
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    • 2000.06a
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    • pp.213-216
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    • 2000
  • In this paper, performance of a CDMA-based packet transmission system is analyzed and simulated in a wireless infrared channel. The indoor wireless infrared channel is modeled as a non-directed diffuse link. The pulse position modulation (PPM) is used as a modulation scheme. From the simulation results, it is shown that the RS coding is very effective in improving the packet-delay characteristics of the CDMA-based packet transmission system. The performance improvement is more significant especially when the infrared channel is in a worse condition.

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Performance of a Turbo-Coded CDMA System in an Indoor Wireless Infrared Channel

  • Kim, Jin-Young;Yoon, Sung-Roh;Heo, Jun
    • Journal of Broadcast Engineering
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    • v.14 no.5
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    • pp.650-653
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    • 2009
  • Turbo-coded CDMA system is analyzed and simulated in an indoor wireless infrared channel. The indoor infrared channel is modeled as a non-directed diffuse link. From the simulation results, it is confirmed that the turbo coding is very effective in improving BER (bit error rate) performance, and outperforms BCH code.

An Improvement on the Self Diagnostic Characteristics of the Triple Quard Channel Infrared Flame Detector (삼파장 4채널 적외선식 불꽃감지기의 자가진단 성능 개선)

  • Song, Hyun Seon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.30 no.1
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    • pp.49-54
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    • 2016
  • There is needed the quard channel triple wave lengths pyroelectric infrared flame detector to recognize the unique characteristics of fire sources in various type. This system detects the triple wave lengths of infrared flame emitting maximum radient energy and scattering frequency of flame. The quard channel infrared flame detector detects the duplicate wave lengths of maximum radient energy to enhance the accuracy of detecting fire. Especially this paper focuss on development of the self diagnosis function system including contamination, temperature and input voltage. Therefore, the prevention and early suppression of fire is available.

A Study of Evaluation Technology for Heating Channel Layout in SMC Molds (SMC 금형의 가열채널레이아웃 평가기술에 관한 연구)

  • 이성희;고영배;이종훈
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.580-584
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    • 2004
  • In the present study, an evaluation technology for heating channel layout was investigated in SMC molding system design. Conventional design rules of cooling channel in injection molding process were applied to the present work. Finite element thermal analysis with ANSYSTM was performed to evaluate the temperature distribution of mold surface. SMC mold was manufactured to test the effect of a proposed heating channel layout system on the temperature distribution of mold surface and infrared camera was applied to a measurement of temperature. It was shown that infrared camera application was possible in a measurement of temperature distribution on mold surface.

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Beating Channel Layout Design and Evaluation Technology for SMC Molds (Sheet Molding Compound 금형의 가열채널설계 및 평가기술)

  • Heo Y. M.;Ko Y. B.;Lee J. H.;Lee S. H.
    • Transactions of Materials Processing
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    • v.14 no.3 s.75
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    • pp.263-268
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    • 2005
  • Heating channel layout design and evaluation technology for SMC molding system was investigated in this work. Traditional rules of cooling channel design in injection molding were applied to the present work. Finite element thermal analysis with $ANSYS^{TM}$ was performed to evaluate the temperature distribution of SHC mold surface. SMC mold was manufactured to evaluate the effect of a proposed heating channel layout system on the temperature distribution of SMC mold surface and infrared camera was applied to a measurement of temperature distribution. It was shown that infrared camera application was possible in a measurement of temperature distribution on SHC mold surface.

INTERCALIBRATION OF THE MTSAT-IR INFRARED CHANNELS WITH A POLAR ORBIT SATELLITE

  • Chung, Sung-Rae;Sohn, Eun-Ha;Ahn, Myoung-Hwan;Ou, Milim;Kim, Mee-Ja
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.554-556
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    • 2005
  • Meteorological imager on the Multi-functional Transport Satellite (MTSAT-IR), which has been operating formally since 28 June 2005, was intercalibrated with a polar orbit satellite [Aqua Moderate Resolution Imaging Spectroradiometer (Aqua/MODIS)] as a well-calibrated instrument. The intercalibration method used in this study was developed by the Cooperative Institute for Meteorological Satellite Studies (CIMSS). This was done for the infrared window channels. The differences of MTSAT-IR and MODIS were are -0.26 K for $11\;\mu m-IR$ window channel, 0.40 K for $12\;\mu m-IR$, window channel, and -0.67 K for $6.7\;\mu m-water$ vapor channel.

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A Multi-Channel Gas Sensor Using Fabry-Perot Interferometer-Based Infrared Spectrometer

  • Choi, Ju Chan;Lee, June Kyoo;Kong, Seong Ho
    • Journal of Sensor Science and Technology
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    • v.21 no.6
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    • pp.402-407
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    • 2012
  • We report a Fabry-Perot interferometer (FPI)-based multi-channel micro-spectrometer used for multi-gas measurement in the spectral range of $3-5{\mu}m$ and its gas sensing performance. The fabricated infrared (IR) spectrometer consists of two parts: an FPI on the top side for selective IR filtering and a $V_2O_5$-based IR detector array on the bottom side for the detection of the filtered IR. Experimental results show that the FPI-based multi-channel gas sensor has reliability and selectivity for simultaneously detecting environmentally harmful gases such as $CH_4$, $CO_2$, $N_2O$ and CO in the spectral range of $3-5{\mu}m$. The fabricated FPI-based multi-channel gas sensor also demonstrated that a reliable and selective detection of gas concentrations ranging from 0 to 500 ppm is feasible. In addition, the electrical characteristics demonstrate a superior response performance in regards to the selectivity in the multi-target gases.

Cloud Analysis Using a Fuzzy Reasoning Method (퍼지 추론 기법을 이용한 구름 분석)

  • Kim, Kwang-Baek;Woo, Young-Woon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1181-1187
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    • 2009
  • In this paper, we proposed a method to analyze kind of clouds using a fuzzy reasoning method. In the proposed method, we used the clues that G channel value is dominant from RGB color values in land areas and B channel value is dominant in the sea areas discovered by the analyses of both visible images and infrared images. By these information, R and B channel values are applied to land areas and R and G channel values are applied to the sea areas. Noise areas(areas except cloud areas) are removed from a visible image and an infrared image by a threshold value, and then land areas and the sea areas are discriminated from the noise removed image. Cloud areas are extracted from discriminated areas using R, G, B channel values and a fuzzy reasoning method, and finally kind of clouds is decided by combining same cloud areas included in both the visible image and the infrared image. In comparison with a conventional quantization method, we verified that the performance of cloud analysis by the proposed method is more efficient through experiments.

Single Image Enhancement Using Inter-channel Correlation

  • Kim, Jin;Jeong, Soowoong;Kim, Yong-Ho;Lee, Sangkeun
    • IEIE Transactions on Smart Processing and Computing
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    • v.2 no.3
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    • pp.130-139
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    • 2013
  • This paper proposes a new approach for enhancing digital images based on red channel information, which has the most analogous characteristics to invisible infrared rays. Specifically, a red channel in RGB space is used to analyze the image contents and improve the visual quality of the input images but it can cause unexpected problems, such as the over-enhancement of reddish input images. To resolve this problem, inter-channel correlations between the color channels were derived, and the weighting parameters for visually pleasant image fusion were estimated. Applying the parameters resulted in significant brightness as well as improvement in the dark and bright regions. Furthermore, simple contrast and color corrections were used to maintain the original contrast level and color tone. The main advantages of the proposed algorithm are 1) it can improve a given image considerably with a simple inter-channel correlation, 2) it can obtain a similar effect of using an extra infrared image, and 3) it is faster than other algorithms compared without artifacts including halo effects. The experimental results showed that the proposed approach could produce better natural images than the existing enhancement algorithms. Therefore, the proposed scheme can be a useful tool for improving the image quality in consumer imaging devices, such as compact cameras.

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An Extraction of Solar-contaminated Energy Part from MODIS Middle Infrared Channel Measurement to Detect Forest Fires

  • Park, Wook;Park, Sung-Hwan;Jung, Hyung-Sup;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.35 no.1
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    • pp.39-55
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    • 2019
  • In this study, we have proposed an improved method to detect forest fires by correcting the reflected signals of day images using the middle-wavelength infrared (MWIR) channel. The proposed method is allowed to remove the reflected signals only using the image itself without an existing data source such as a land-cover map or atmospheric data. It includes the processing steps for calculating a solar-reflected signal such as 1) a simple correction model of the atmospheric transmittance for the MWIR channel and 2) calculating the image-based reflectance. We tested the performance of the method using the MODIS product. When compared to the conventional MODIS fire detection algorithm (MOD14 collection 6), the total number of detected fires was improved by approximately 17%. Most of all, the detection of fires improved by approximately 30% in the high reflection areas of the images. Moreover, the false alarm caused by artificial objects was clearly reduced and a confidence level analysis of the undetected fires showed that the proposed method had much better performance. The proposed method would be applicable to most satellite sensors with MWIR and thermal infrared channels. Especially for geostationary satellites such as GOES-R, HIMAWARI-8/9 and GeoKompsat-2A, the short acquisition time would greatly improve the performance of the proposed fire detection algorithm because reflected signals in the geostationary satellite images frequently vary according to solar zenith angle.