• Title/Summary/Keyword: signal comparison

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Performance Comparison of Neural Network Algorithm for Shape Recognition of Welding Flaws (초음파 검사 기반의 용접결함 분류성능 개선에 관한 연구)

  • 김재열;윤성운;김창현;송경석;양동조
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.04a
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    • pp.287-292
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    • 2004
  • In this study, we made a comparative study of backpropagation neural network and probabilistic neural network and bayesian classifier and perceptron as shape recognition algorithm of welding flaws. For this purpose, variables are applied the same to four algorithms. Here, feature variable is composed of time domain signal itself and frequency domain signal itself, Through this process, we confirmed advantages/disadvantages of four algorithms and identified application methods of few algorithms.

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Performance Comparison of Welding Flaws Classification using Ultrasonic Nondestructive Inspection Technique (초음파 비파괴 검사기법에 의한 용접결함 분류성능 비교)

  • 김재열;유신;김창현;송경석;양동조;김유홍
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.10a
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    • pp.280-285
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    • 2004
  • In this study, we made a comparative study of backpropagation neural network and probabilistic neural network and bayesian classifier and perceptron as shape recognition algorithm of welding flaws. For this purpose, variables are applied the same to four algorithms. Here, feature variable is composed of time domain signal itself and frequency domain signal itself. Through this process, we comfirmed advantages/disadvantages of four algorithms and identified application methods of four algorithms.

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Cut Detection of Video Data Using Color Histogram and Entropy (컬러 히스토그램과 엔트로피를 이용한 동영상 컷 검출)

  • 송현석;안강식;안명석;조석제
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2001.06a
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    • pp.265-268
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    • 2001
  • In content-based video data retrieval, the representative-frame is usually used. To do that, the skill of detection for scene change is needed. Generally the color histogram comparison is used, but sensitive to light variation and tends to miss the scene change of similar color histogram. This paper shows how to use both color histogram comparison and entropy to prevent the false-positive of scene change occurred by light variation. At the experiments, il is more powerful to light variation to use both color histogram comparison entropy than to use only color histogram comparison.

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Development of an International Time Comparison System via GMS (정지기상위성을 이용한 국제시각비교시스템의 개발)

  • 이창복;이동두;정낙삼;장익수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.11
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    • pp.1238-1246
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    • 1992
  • We developed a time comparison system using the ranging signal of the geostationary meteorological satellite(GMS). By using the system time comparison between the KRISS(Korea Research Institute of Standards and Science) cesium atomic clock and the GMS ranging signal has been carried out and the results have shown that the precision of time comparison at KRISS is about 10 ns. For the more accurate measurements we calibrated the receiver delay time between KRISS receiver and CRL(Communications Research Laboratory) receiver by using the portable GMS receiver.

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The Design of Reliable Graphics-DTV Signal Converter Using EDAC Algorithm in DTV System

  • Ryoo, Dong-Wan;Lee, Jeun-Woo
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2126-2130
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    • 2003
  • In the integrated systems, that is integrated digital TV(DTV) internet and home automation, like home server, is needed integration of digital TV video signal and computer graphic signal. The graphic signal is operating at the high speed and has time-divide-stream. So the re-request of data is not easy at the time of error detection. therefore EDAC algorithm is efficient. In this paper, we show a scheme, that is integration of graphic and dtv format signal for DTV monitor display. This paper also presents the efficiency error detection auto correction(EDAC) for conversion of graphics signal to DTV video signal. A presented EDAC algorithms use the modified hamming code for enhancing video quality and reliability. A EDAC algorithm of this paper can detect single error, double error, triple error and more error for preventing from incorrect correction. And it is not necessary an additional memory. In this paper The comparison between digital TV video signal and graphic signal, a EDAC algorithm and a design of conversion graphic signal to DTV signal with EDAC function in DTV system is described.

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Effects of Contrast Agent Concentration on the Signal Intensity and Turbo Factor of TSE and Slice-selective IR in T1-weighted Contrast Imaging

  • Han, Yong Soo;Lee, Soo Chul;Lee, Dong Yong;Choi, Jiwon;Lee, Jong Woong;Kweon, Dae Cheol
    • Journal of Magnetics
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    • v.21 no.1
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    • pp.115-124
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    • 2016
  • The present study analyzes T1 TSE and T1 slice sel. IR (dark_fluid) signal strength according to the degree of gadolinium contrast agent dilution and analyzes the turbo factors with regard to changes in the maximum and overall signal strength to study correlations between changes and signal-to-noise ratios (SNRs) and compare peak-to-peak SNR (PSNR) enhancement in order to improve the quality of T1-weighted images. Enhancement TR (600 msec) evaluated to determine the T1 TSE turbo factor and obtain the maximum signal strength, T1WI were used sequentially to experiment with turbo factors_1-4. T1 slice sel. IR (dark-fluid) was used to sequentially test turbo factors_2-5 but not turbo factor_1 at a TR (1500 msec) and compare data at an increase in T1 of 900 msec. The T1 TSE was reduced according to the contrast agent concentration. Phantom signal strength increased, whereas turbo factors_1-4 exhibited maximum signal strength at a concentration of 3 mmol, followed by a gradual decrease. In the turbo factors_2-5, the signal strength increased sharply to maximum signal strength at 0.7 mmol, followed by a reduction. T1 TSE had a greater maximum signal strength than did T1 slice sel. IR (dark_fluid). A comparison of SNR found that T1 TSE imaging was superior (33.3 dB) in turbo factor_1 and T1 slice sel. IR (dark_fluid) was highest (33.9 dB) at turbo factor_5. A PSNR comparison analysis was not sufficient to distinguish between the images obtained with both techniques at 30 dB or higher under all experimental conditions.

The Design of Error Detection Auto Correction for Conversion of Graphics to DTV Signal

  • Ryoo-Dongwan;Lee, Jeonwoo
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.106-109
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    • 2002
  • In the integrated systems, that is integrated digital TV(DTV) internet and home automation, like home server, is needed integration of digital TV video signal and computer graphic signal. The graphic signal is operating at the high speed and has time-divide-stream. So the re-request of data is not easy at the time of error detection. therefore EDAC algorithm is efficient. This paper presents the efficiency error detection auto correction(EDAC) for conversion of graphics signal to DTV video signal. A presented EDAC algorithms use the modified Hamming code for enhancing video quality and reliability. A EDAC algorithm of this paper can detect single error, double error, triple error and more error for preventing from incorrect correction. And it is not necessary an additional memory. In this paper The comparison between digital TV video signal and graphic signal, a EBAC algorithm and a design of conversion graphic signal to DTV signal with EDAC function is described.

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The Method of Measurement Signal Processing of Biosensor Based on Optical Fiber Using Reflected Localized Surface Plasmon Resonance (반사된 국소화 표면 플라즈몬 공명 신호를 이용한 광섬유기반 바이오센서의 측정 신호처리 방법)

  • Jeong, Hyeon-Ho;Lee, Seung-Ki
    • Journal of Sensor Science and Technology
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    • v.20 no.2
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    • pp.107-113
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    • 2011
  • LSPR(Localized Surface Plasmon Resonance) sensor measures the refractive index change on the sensor surface. The detection of biological reaction with the unknown refractive index needs to be converted into the signal sensitivity for the refractive index change for comparison with other measurements. To find the signal sensitivity, the three steps of signal processing are proposed, which are signal modeling, signal calibration and signal normalization of LSPR sensor. The detected signal of biotin-streptavidin interaction has been converted into unit of [RU](Resonance Unit) using the proposed method. The converted signal directly can be compared with the other sensors including commercialized one.

Comparison of On-Line Diagnotic Methods on Multi-Channel Signals in Nuclear Plant (원자력발전소 다채널 신호의 온라인 진단방법 비교)

  • Lee, Kwang-Dae;Yang, Seung-Ok
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.705-708
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    • 2003
  • In this paper, we have evaluated the methods to generate the reference signal for the diagnosis of multi-channel signals. The channel signal integrity can be known by the difference between the reference signal and each channel value. The generation method of reference signal is important in the diagnosis of multi-channel measurement system. The continuous weighting average method rejects the abnormal signal using weighting method and makes the reference signal using sumation of all channel values. This gives the simple and reasonable reference signal. The principle component analysis, one of the multivariate analysis methods, and the neural network method give the reliable reference signal by using signal models, and learning algorithm. Two methods can make the reliable reference if all signals are normal, but any signal having the drift have an effect on the reference.

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Segmentation-based Signal Processing Algorithm for Vehicle Detection (차량검지를 위한 세그먼트에 기반을 둔 신호처리 알고리즘)

  • Ko, Ki-Won;Woo, Kwang-Joon
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.306-308
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    • 2005
  • The vehicle detection method using pulse radar has the advantage of maintenance in comparison with loop detection method. We have the information about the vehicle being and position by dividing the signals into sectors in accordance with SSC method, and by applying the discriminant function based on stochastical data. We also reduce the signal processing time.

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