• Title/Summary/Keyword: Approximation Method

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Automatic classification of power quality disturbances using orthogonal polynomial approximation and higher-order spectra (직교 다항식 근사법과 고차 통계를 이용한 전력 외란의 자동식별)

  • 이재상;이철호;남상원
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1436-1439
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    • 1997
  • The objective of this paper is to present an efficient and practical approach to the automatic classification of power quality(PQ) disturbances, where and orthogonal polynomial approximation method is emloyed for the detection and localization of PQ disturbances, and a feature vector, newly extracted form the bispectra of the detected signal, is utilized for the automatic rectgnition of the various types of PQ disturbances. To demonstrae the performance and applicabiliyt of the proposed approach, some simulation results are provided.

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VISCOSITY METHODS OF APPROXIMATION FOR A COMMON SOLUTION OF A FINITE FAMILY OF ACCRETIVE OPERATORS

  • Chen, Jun-Min;Zhang, Li-Juan;Fan, Tie-Gang
    • East Asian mathematical journal
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    • v.27 no.1
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    • pp.11-21
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    • 2011
  • In this paper, we try to extend the viscosity approximation technique to find a particular common zero of a finite family of accretive mappings in a Banach space which is strictly convex reflexive and has a weakly sequentially continuous duality mapping. The explicit viscosity approximation scheme is proposed and its strong convergence to a solution of a variational inequality is proved.

THE DISCRETE SLOAN ITERATE FOR CAUCHY SINGULAR INTEGRAL EQUATIONS

  • KIM, SEKI
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.2 no.2
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    • pp.81-95
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    • 1998
  • The superconvergence of the Sloan iterate obtained from a Galerkin method for the approximate solution of the singular integral equation based on the use of two sets of orthogonal polynomials is investigated. The discrete Sloan iterate using Gaussian quadrature to evaluate the integrals in the equation becomes the Nystr$\ddot{o}$m approximation obtained by the same rules. Consequently, it is impossible to expect the faster convergence of the Sloan iterate than the discrete Galerkin approximation in practice.

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THE COMPUTATION OF MULTIVARIATE B-SPLINES WITH APPLICATION TO SURFACE APPROXIMATIONS

  • KIM, HOI SUB
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.3 no.1
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    • pp.81-98
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    • 1999
  • In spite of the well developed theory and the practical use of the univariate B-spline, the theory of multivariate B-spline is very new and waits its practical use. We compare in this article the multivariate B-spline approximation with the polynomial approximation for the surface fitting. The graphical and numerical comparisons show that the multivariate B-spline approximation gives much better fitting than the polynomial one, especially for the surfaces which vary very rapidly.

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연속 근사형 전하 전달 A/D 변환기

  • 박종안;문용선
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1986.10a
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    • pp.68-71
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    • 1986
  • A new circuit configuration for charge-balancing successive approximation Analog-to-Digital converters is described. This consists of a improved successive approximation register(SAR) and a weighted capacitor Digital-to-Analog converter (WCDAC). Due to the inherent conversion property of the WCDAC, the A/D converter using the WCDAC can be simply implemented by successive approximation conversion method, and 4bit monotonicity conversion with differential nonlinearity less 1/2LSB is completed in 80 US.

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Tail Probability Approximations for the Ratio of the Independent Random Variables

  • Cho, Dae-Hyeon
    • Journal of the Korean Data and Information Science Society
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    • v.7 no.2
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    • pp.189-201
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    • 1996
  • In this paper, we study the saddlepoint approximations for the ratio of independent random variables. In Section 2, we derive the saddlepoint approximation to the density. And in Section 3, we derive two approximation formulae for the tail probability, one by following Daniels'(1987) method and the other by following Lugannani and Rice's (1980). In Section 4, we represent some numerical examples which show that the errors are small even for small sample size.

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Sliding Mode Controller Design Considering Weight (가중치를 고려한 슬라이딩 모드 제어기 설계)

  • 임동균;서병설
    • Proceedings of the KIPE Conference
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    • 1998.11a
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    • pp.73-77
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    • 1998
  • The conventional sliding mode controller (SMCr) approach is often impractical or difficult when applied to high order process because the number of tuning parameters in the SMCr increases with the order of the plant. Camacho(1996) proposed the design of a fixed structure sliding mode controller based on a first order plus dead time approximation to the higher-order process. But, there are such problems as overshoot, settling time and command following. They are mainly due to the approximation errors of the time delay term by Taylor series. In this paper, in order to improve Camcho's method, a new Taylor approximation technique considering a weight is proposed.

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ON SOME OUTSTANDING PROBLEMS IN NUCLEAR REACTOR ANALYSIS

  • Cho, Nam-Zin
    • Nuclear Engineering and Technology
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    • v.44 no.2
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    • pp.207-224
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    • 2012
  • This article discusses selects of some outstanding problems in nuclear reactor analysis, with proposed approaches thereto and numerical test results, as follows: i) multi-group approximation in the transport equation, ii) homogenization based on isolated single-assembly calculation, and iii) critical spectrum in Monte Carlo depletion.

APPROXIMATION-SOLVABILITY OF A CLASS OF A-MONOTONE VARIATIONAL INCLUSION PROBLEMS

  • Verma, Ram U.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.8 no.1
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    • pp.55-66
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    • 2004
  • First the notion of the A-monotonicity is applied to the approximation - solvability of a class of nonlinear variational inclusion problems, and then the convergence analysis is given based on a projection-like method. Results generalize nonlinear variational inclusions involving H-monotone mappings in the Hilbert space setting.

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KOLMOGOROV DISTANCE FOR MULTIVARIATE NORMAL APPROXIMATION

  • Kim, Yoon Tae;Park, Hyun Suk
    • Korean Journal of Mathematics
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    • v.23 no.1
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    • pp.1-10
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    • 2015
  • This paper concerns the rate of convergence in the multidimensional normal approximation of functional of Gaussian fields. The aim of the present work is to derive explicit upper bounds of the Kolmogorov distance for the rate of convergence instead of Wasserstein distance studied by Nourdin et al. [Ann. Inst. H. Poincar$\acute{e}$(B) Probab.Statist. 46(1) (2010) 45-98].