• Title/Summary/Keyword: Integral Transform

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A Multiple Features Video Copy Detection Algorithm Based on a SURF Descriptor

  • Hou, Yanyan;Wang, Xiuzhen;Liu, Sanrong
    • Journal of Information Processing Systems
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    • v.12 no.3
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    • pp.502-510
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    • 2016
  • Considering video copy transform diversity, a multi-feature video copy detection algorithm based on a Speeded-Up Robust Features (SURF) local descriptor is proposed in this paper. Video copy coarse detection is done by an ordinal measure (OM) algorithm after the video is preprocessed. If the matching result is greater than the specified threshold, the video copy fine detection is done based on a SURF descriptor and a box filter is used to extract integral video. In order to improve video copy detection speed, the Hessian matrix trace of the SURF descriptor is used to pre-match, and dimension reduction is done to the traditional SURF feature vector for video matching. Our experimental results indicate that video copy detection precision and recall are greatly improved compared with traditional algorithms, and that our proposed multiple features algorithm has good robustness and discrimination accuracy, as it demonstrated that video detection speed was also improved.

Comparative Analysis of the Parabolic and Hyperbolic Heat Conduction and the Damped Wave in a Finite Medium (유한한 평판에서 포물선형 및 쌍곡선형 열전도 방정식과 파동 방정식의 비교 해석)

  • Park, S.K.;Lee, Y.H.
    • Journal of Power System Engineering
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    • v.3 no.3
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    • pp.14-21
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    • 1999
  • The wave nature of heat conduction has been developed in situations involving extreme thermal gradients, very short times, or temperatures near absolute zero. Under the excitation of a periodic surface heating in a finite medium, the hyperbolic and parabolic heat conduction equations and the damped wave equations in heat flux are presented for comparative analysis by using the Green's function with the integral transform technique. The Kummer transformation is also utilized to accelerate the rate of convergence of these solutions. On the other hand, the temperature distributions are obtained through integration of the energy conservation law with respect to time. For hyperbolic heat conduction, the heat flux distribution does not exist throughout all the region in a finite medium within the range of very short times(${\xi}<{\eta}_l$). It is shown that due to the thermal relaxation time, the hyperbolic heat conduction equation has thermal wave characteristics as the damped wave equation has wave nature.

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EMG Pattern Recognition based on Evidence Accumulation for Prosthesis Control

  • Lee, Seok-Pil;Park, Sand-Hui
    • Journal of Electrical Engineering and information Science
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    • v.2 no.6
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    • pp.20-27
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    • 1997
  • We present a method of electromyographic(EMG) pattern recognition to identify motion commands for the control of a prosthetic arm by evidence accumulation with multiple parameters. Integral absolute value, variance, autoregressive(AR) model coefficients, linear cepstrum coefficients, and adaptive cepstrum vector are extracted as feature parameters from several time segments of the EMG signals. Pattern recognition is carried out through the evidence accumulation procedure using the distances measured with reference parameters. A fuzzy mapping function is designed to transform the distances for the application of the evidence accumulation method. Results are presented to support the feasibility of the suggested approach for EMG pattern recognition.

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Mathematical Andysis of Imaging Conception (수학적 영상개념)

  • 박일영
    • Progress in Medical Physics
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    • v.3 no.2
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    • pp.67-81
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    • 1992
  • Lots of physical phenomena which deteriorate the faithfulness of radiological images exist. The most common types of degradation are a loss of resolution and an increase in noise. This article deals with resolution. factors that influence it. and its characterisation. The problem of resolution failure due to a generic blurring phenomenum is described diagramatically and mathematically. for both one dimensional and two dimensional signals. The definition of the point spread function. the line spread function. the convolution integral and the modulation transfer function are made. The concept of frequency domain operations using the Fourier Transform is also discussed.

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An Analysis of Elastic Wave Propagation in Multilayered Media (다층구조물내의 탄성파 전파해석)

  • 김현실
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.04a
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    • pp.143-150
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    • 1999
  • Elastic wave propagation in a multilayered elastic half-plane is studied by using the Cagniard-de Hoop method. After the unknowns are expressed in terms of the reflection and transmission coefficients in the in terms of the reflection and transmission coefficients in the integral-transformed domains they are assmbled to form the global matrix equation. The inverse Laplace transform of each term is done by applying the Cagniard-de Hoop methods. As a numerical example a four-layered half-plane is considered where a point source is applied to the first layer. The method described in the present study can be used in checking other numerical methods such as FDM.

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Extension of Generalized Hurwitz-Lerch Zeta Function and Associated Properties

  • Choi, Junesang;Parmar, Rakesh Kumar;Raina, Ravinder Krishna
    • Kyungpook Mathematical Journal
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    • v.57 no.3
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    • pp.393-400
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    • 2017
  • Very recently, Srivastava et al. [8] introduced an extension of the Pochhammer symbol and used it to define a generalization of the generalized hypergeometric functions. In this paper, by using the generalized Pochhammer symbol, we extend the generalized Hurwitz-Lerch Zeta function by Goyal and Laddha [6] and investigate some interesting properties which include various integral representations, Mellin transforms, differential formula and generating function. Some interesting special cases of our main results are also considered.

Feedback stabilization of linear systems with delay in state (상태변수에 지연요소를 갖는 시스템의 안정화 방법에 관한 연구)

  • 권욱현;임동진
    • 전기의세계
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    • v.31 no.1
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    • pp.59-67
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    • 1982
  • This paper suggests easy stabilization methods for linear time-varying systems with delay in the state. While existing methods employ the function space concept, the methods introduced in this paper transform the delay systems into the non-delay systems so that the well known methods for finite dimensional systems can be utilized. Particularly the intervalwise predictor is introduced and shown to satisfy an ordinary system. Control laws stabilizing the non-delay systems satisfied by this predictor will be shown to at least pointwise stabilize the delay systems with the additional strong possibility of true stabilization. In order to combine two steps of the predictor method, first transformation and then stabilization, an intervalwise regulator problem is suggested whose optimal control laws incorporate the intervalwise predictor as an integral part and also at least pointwise stabilize the delay systems. Since the above mentioned methods render the periodic feedback gains for time invariant systems the pointwise predictor and regulator are introduced in order to obtain the constant feedback gains, with additional stability properties. The control laws given in this paper are perhaps simplest and easiest to implement.

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A Study on Tuning of Current Controller for Grid-connected Inverter Using Particle Swarm Optimization (PSO를 이용한 계통연계형 인버터 전류제어기의 자동조정에 관한 연구)

  • Ahn Jong-Bo;Kim Won-gon;Hwang Ki-Hyun;Park Jun-H
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.11
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    • pp.671-679
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    • 2004
  • This paper presents the on-line current controller tuning method of grid-connected inverter using PSO(particle swarm optimization) technique for minimizing the harmonic current. Synchronous frame PI current regulator is commonly used in most distributed generation. However, due to the source voltage distortion, specially in weak AC power system, current may contain large harmonic components, which increase THD(total harmonic distortion) and deteriorates power quality. Therefore, some tuning method is necessary to improve response of current controller. This paper used the PSO technique to tune the current regulator and through simulation and experiments, usefulness of the tuning method has been verified. Especially in simulating the tuning process, ASM(average switching model) of inverter is used to shorten execution time.

An Application of k-domain Discrete Wavelet Transform for the Efficient Representation of Green Function (파수영역 이산 웨이블릿 변환을 이용한 효율적인 그린함수 표현에 관한 연구)

  • 주세훈;김형동
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.7
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    • pp.1110-1114
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    • 2001
  • The discrete wavelet concept in the k-domain is applied to efficiently represent Green function of integral equations. Application of discrete wavelet concept to Green function in the k-domain can be implemented equivalently by using spatial domain variable-sized windows. The proposed method consists of constant Q-filtering, changing the center of coordinates, and transforming spatially filtered Green functions into those in the k-domain. A mathematical expression of Green function based on the discrete wavelet concept is derived and its characteristics are discussed.

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Laser Ultrasonic Inspection of Environmental Barrier Coatings

  • Murray, T.W.;Balogun, O.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.22 no.6
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    • pp.599-608
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    • 2002
  • The mechanical properties of mullite $(3Al_2O_3\;2SiO_2)$ environmental barrier coatings are determined using a laser-based ultrasonic system. The waveforms generated by a laser source in mullite coatings in the $1-20{\mu}m$ thickness range are evaluated theoretically using the integral transform technique. It is shown that the laser source generated the two lowest order SAW modes in these systems. Experimental waveforms are generated using a 600ps pulsed Nd:YAG microchip laser and detected using a stabilized Michelson interferometer. The dispersion curves for the generated modes are extracted from the experimental data and the mechanical properties of the coatings are obtained by minimizing the error between the measured and calculated velocity values. The waveforms generated in mullite coatings agree well with theory and laser-based ultrasonics is shown to provide an effective tool for the nondestructive evaluation of ceramic coatings.