• Title/Summary/Keyword: Signal Detector

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A Study On Development of Fast Image Detector System (고속 영상 검지기 시스템 개발에 관한 연구)

  • Kim Byung Chul;Ha Dong Mun;Kim Yong Deak
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.41 no.1
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    • pp.25-32
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    • 2004
  • Nowadays image processing is very useful for some field of traffic applications. The one reason is we can construct the system in a low price, the other is the improvement of hardware processing power, it can be more fast to processing the data. In traffic field, the development of image using system is interesting issue. Because it has the advantage of price of installation and it does not obstruct traffic during the installation. In this study, 1 propose the traffic monitoring system that implement on the embedded system environment. The whole system consists of two main part, one is host controller board, the other is image processing board. The part of host controller board take charge of control the total system interface of external environment, and OSD(On screen display). The part of image processing board takes charge of image input and output using video encoder and decoder, Image classification and memory control of using FPGA, control of mouse signal. And finally, for stable operation of host controller board, uC/OS-II operating system is ported on the board.

Fast LFM Target Detection Method with Robustness for Doppler Shift in Narrow-Band Sonar Systems (협대역 소나시스템에서 도플러 천이에 강인한 고속 LFM 표적 검출기법)

  • Choi, Sang-Moon;Do, Dae-Won;Kim, Woo-Sik;Lee, Dong-Hun;Kim, Hyung-Moon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.8
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    • pp.114-125
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    • 2014
  • In a conventional sonar system, which uses LFM signal for detecting targets with varying speed, the results of multiple LFM Doppler correlators are aligned and the maximum alined result are selected as a test cell for detecting targets. As the number of the LFM Doppler correlators are increased for accurate target detection, as the required computational complexity and the memory are also increased. This fact makes it difficult to implement the accurate LFM target detector. In this paper, we propose a new fast target detection which is robust for the variation of target speed. Because the proposed method uses the summation of alined results of large numbers of LFM Doppler correlators, the proposed method increase SNR and provide robust SNR for the variation of target speed. And the proposed method can provide very fast target detection by implementing the process, the summation of alined results of large numbers of LFM Doppler correlators, as one summation filter.

Visible Light Wireless Communication Link Using LEDs (LED를 이용한 가시광 무선 통신 링크)

  • Son, Yong-Hwan;An, Sung-Chan;Kim, Hyun-Seung;Won, Yong-Yuk;Han, Sang-Kook
    • Journal of IKEEE
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    • v.13 no.4
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    • pp.70-74
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    • 2009
  • In this paper, We propose the visible light communication(VLC) link based on white light emitting diode (LED) and Photo detector(PD). The proposed architecture is demonstrated experimentally and its performance is verified through the experimental results of quality-factor(Q-factor) and eye pattern of 10Mb/s PRBS signal. The ambient light effect from a typical type fluorescent lamp source was also analyzed. when the distance between the LED and the PD is about 1m, error free wireless transmission of the LED was achieved up to 10Mb/s data rate. Under the condition with ambient light, low BER, data transmission of the VLC link is achieved up to 5Mb/s data rate at 1m. Also, when the PD is placed away from the center, low BER data transmission of the VLC link is achieved up to 1Mb/s at 10cm and 10Mb/s at 5cm.

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A Signal Detection Method based on the Double Detection for Spatially Multiplexed MIMO Systems (다중 안테나 시스템을 위한 이중 검출 기반의 신호검출 기법)

  • Kim, Jung-Hyun;Bahng, Seung-Jae;Park, Youn-Ok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6C
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    • pp.634-641
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    • 2009
  • The goal of OSIC-series detection methods is to approach the ML performance with feasible complexity. However, since they sometimes suffer from the empty vector problem, they can not achieve the soft-output ML performance or many candidate vectors are required to achieve the soft-output ML performance. In this paper, we propose the novel detection method, which can generate the reliable soft-outputs without suffering from empty vector problem. The proposed detector can approach the near soft-output ML performance as well as hard-output. Further, the complexity study shows that the proposed detection method has the lowest complexity compared to the other detectors having the near ML performance.

Normalized CP-AFC with multistage tracking mode for WCDMA reverse link receiver (다단 추적 모드를 적용한 WCDMA 역방향 링크 수신기용 Normalized CP-AFC)

  • Do, Ju-Hyeon;Lee, Yeong-Yong;Kim, Yong-Seok;Choe, Hyeong-Jin
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.8
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    • pp.14-25
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    • 2002
  • In this paper, we propose a modified AFC algorithm which is suitable for the implementation of WCDMA reverse link receiver modem. To reduce the complexity, the modified CP-FDD algorithm named 'Normalized CP-FDD' is applied to the AFC loop. The proposed FDD algorithm overcomes the conventional CP-FDD's sensitivity to the variance of input signal amplitude and increases the linear range of S -curve. Therefore, offset frequency estimation using the proposed scheme can be more stable than the conventional method. Unlike IS-95, since pilot symbol in WCDMA is not transmitted continuously, we introduce a moving average filter at the FDD input to increase the number of cross-product. So, tracking speed and stability are improved. For more rapid frequency acquisition and tracking, we adopt a multi-stage tracking mode. Using NCO having ROM table structure, the frequency offset is compensated. We applied the proposed algorithm in the implementation of WCDMA base station modem successfully.

Development of Deterioration Diagnosis System for Aged ACSR-OC Conductors in HV Overhead Distribution Lines (고압 가공배전선의 노화된 ACSR-OC 도체에 대한 열화진단시스템 개발)

  • 김성덕;이승호
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.6
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    • pp.43-50
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    • 2000
  • Design and experiments of a nondestructive testing system with a solenoid eddy current sensor to inspect deterioration of ASCR-OC (ACSR Outdoor Cross-linked Polyethylene Insulated Wires) usually used in HV overhead distribution lines in domestic areas in presented in this paper. Through corrosion mechanisms and deterioration results for ACSR-OC conductors are examined, it is shown that corrosion may lead to the reduction of the effective cross section area of conductors is proposed. The measurement system consisting of a constant current source with a RF frequency, a signal processing unit and a motor driver/ controller is designed and implemented. This instrument has such capabilities as detecting the sensor output and estimating diameter change of the testing conductors, continuously. As a result, it was verified that such corrosion detector system with an eddy current sensor can be shown good effectiveness for estimating the serious faults due to deterioration in overhead distribution lines and giving an early warming before severe aged conductor may lead to fail.

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Hybrid Filter Based on Neural Networks for Removing Quantum Noise in Low-Dose Medical X-ray CT Images

  • Park, Keunho;Lee, Hee-Shin;Lee, Joonwhoan
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.15 no.2
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    • pp.102-110
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    • 2015
  • The main source of noise in computed tomography (CT) images is a quantum noise, which results from statistical fluctuations of X-ray quanta reaching the detector. This paper proposes a neural network (NN) based hybrid filter for removing quantum noise. The proposed filter consists of bilateral filters (BFs), a single or multiple neural edge enhancer(s) (NEE), and a neural filter (NF) to combine them. The BFs take into account the difference in value from the neighbors, to preserve edges while smoothing. The NEE is used to clearly enhance the desired edges from noisy images. The NF acts like a fusion operator, and attempts to construct an enhanced output image. Several measurements are used to evaluate the image quality, like the root mean square error (RMSE), the improvement in signal to noise ratio (ISNR), the standard deviation ratio (MSR), and the contrast to noise ratio (CNR). Also, the modulation transfer function (MTF) is used as a means of determining how well the edge structure is preserved. In terms of all those measurements and means, the proposed filter shows better performance than the guided filter, and the nonlocal means (NLM) filter. In addition, there is no severe restriction to select the number of inputs for the fusion operator differently from the neuro-fuzzy system. Therefore, without concerning too much about the filter selection for fusion, one could apply the proposed hybrid filter to various images with different modalities, once the corresponding noise characteristics are explored.

Noise Reduction of medical X-ray Image using Wavelet Threshold in Cone-beam CT (Cone-beam CT에서 웨이브렛 역치값을 이용한 x-ray 영상에서의 노이즈 제거)

  • Park, Jong-Duk;Huh, Young;Jin, Seung-Oh;Jeon, Sung-Chae
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.44 no.6
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    • pp.42-48
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    • 2007
  • In x-ray imaging system, two kinds of noises are involved. First, the charge generated from the radiation interaction with the detector during exposure. Second, the signal is then added by readout electronics noise. But, x-ray images are not modeled by Gaussian noise but as the realization of a Poisson process. In this paper, we apply a new approach to remove Poisson noise from medical X-ray image in the wavelet domain, the applied methods shows more excellent results in cone-beam CT.

A Study on Neutron Resonance Energy of Tantalum by 46-MeV Electron Linac TOF Method (46-MeV 전자선형가속기의 TOF 방법을 이용한 탄탈의 중성자 공명 에너지 분석에 관한 연구)

  • Lee, Samyol
    • Journal of the Korean Society of Radiology
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    • v.7 no.3
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    • pp.245-249
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    • 2013
  • Neutron sources from photonuclear reaction with 46-MeV electron linear accelerator at Research Reactor Institute, Kyoto University used for resonance energy measurement of natural tantalum. BGO($Bi_4Ge_3O_{12}$) scintillation detectors used for measurement of the prompt gamma ray from the natural tantalum sample. The BGO spectrometer was composed geometrically as total energy absorption detector. The electric signal from the spectrometer was analyzed for TOF(Time-of-Flight) spectrum which is used identification of neutron capture resonance energy. In this study, the neutron energy region is from 1 to 200 eV, because of strong X-ray effect produced photonuclear reaction in Ta target, the measurement was performed to below 1 keV energy region. The resonance energy was compared with the evaluated values(ENDF/B-VI, Mughabghab). All of the resonances from 4.28 ~ 200 eV were seen in the present measurement except 144.3 eV resonance.

Coupling Efficiencies of m1, m3 and m5 Muscarinic Receptors to the Stimulation of Neuronal Nitric Oxide Synthase

  • Park, Sun-Hye;Lee, Seok-Yong;Cho, Tai-Soon
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.207-207
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    • 1996
  • Through molecular cloning, five muscarinic receptors have been identified. The muscarinic receptors can be generally grouped according to their coupling to either stimulation of phospholipase C (m1, m3, and m5) or the inhibition of adenylate cyclase (m2 and m4). Each m1, m3, and m5 receptors has the additional potential to couple to the activation of phospholipase A$_2$, C, and D, tyrosine kinase, and the mobilization of Ca$\^$2+/. However, the differences in coupling efficiencies to different second messenger systems between these receptors have not been studied well. Ectopic expression of each of these receptors in mammalian cells has provided the opportunity to evaluate the signal transduction of each in some detail. In this work we compared the coupling efficiencies of the m1, m3 and m5 muscarinic receptors expressed in chinese hamster ovary (CHO) cells to the Ca$\^$2+/ mobilization and the stimulation of neuronal nitric oxide synthase (nNOS). Because G protein/PLC/PI turnover/[(Ca$\^$2+/])i/NOS pathway was supposed as a main pathway for the production of nitric oxide via muscarinic receptors, we studied on ml, m3 and m5 receptors. Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an index of generation nitric oxide (NO) in CHO cells. The agonist carbachol increased the cGMP formation and the intracellular [Ca$\^$2+/] in concentration dependent manner in three types of receptors and the increased cGMP formation was significantly attenuated by scavenger of NO or inhibitor of NOS. m5 receptors was most efficiently coupled to stimulation of nNOS, And, the coupling efficiencies to the stimulation of neuronal nitric oxide synthase in three types of receptors were parallel with them to the Ca$\^$2+/ mobilization.

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