• Title/Summary/Keyword: least squares

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Nonlinear self-tuning control incorporating cautious estimation

  • James, D.J.G.;Burnham, K.J.
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.227-230
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    • 1996
  • The paper highlights the need for cautious least squares estimation when dealing with industrial applications of bilinear self-tuning control and indicates in qualitative terms the benefits of the approach over linear self-tuning control schemes. The cautious least squares algorithm is described and the use of cautious self-tuning in the context of both commissioning and implementation discussed.

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Identification of suspension systems using error self recurrent neural network and development of sliding mode controller (오차 자기 순환 신경회로망을 이용한 현가시스템 인식과 슬라이딩 모드 제어기 개발)

  • 송광현;이창구;김성중
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.625-628
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    • 1997
  • In this paper the new neural network and sliding mode suspension controller is proposed. That neural network is error self-recurrent neural network. For fast on-line learning, this paper use recursive least squares method. A new neural networks converges considerably faster than the backpropagation algorithm and has advantages of being less affected by the poor initial weights and learning rate. The controller for suspension systems is designed according to sliding mode technique based on new proposed neural network.

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FFT-Based Block Least Mean Squares Adaptive Equalizer using Antenna Arrays for High Speed Wireless Communications. (안테나 배열을 이용한 FFT-Block LMS 방식의 적응형 등화기)

  • 류원형;오성근
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.167-170
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    • 1998
  • 본 논문에서는 주파수 영역에서 구현되는 안테나 배열을 이용한 적응형 등화기의 구조를 제안하였다. 제안된 방식은 주파수 영역에서 블록 LMS (least mean squares) 방식을 사용하기 때문에 수렴 속도가 빠르고 계산량이 적다. 또한 안테나 배열을 사용함으로서 다중경로 환경에서 한 개의 안테나를 사용한 경우에 비해 특히 우수한 성능을 지닌다. 다중 경로를 통한 신호들을 분리하기 위해 학습신호를 사용하여 반복적으로 출력신호와의 오차를 최소화하는 방법을 사용하였다. 시뮬레이션을 통하여 안테나의 개수, 신호의 입사각, 세기 등에 따른 성능을 분석하고, 제안된 방식이 다이버시티 시스템에 사용되는 경우에 대하여도 성능을 분석하였다.

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Prediction Intervals for LS-SVM Regression using the Bootstrap

  • Shim, Joo-Yong;Hwang, Chang-Ha
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.2
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    • pp.337-343
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    • 2003
  • In this paper we present the prediction interval estimation method using bootstrap method for least squares support vector machine(LS-SVM) regression, which allows us to perform even nonlinear regression by constructing a linear regression function in a high dimensional feature space. The bootstrap method is applied to generate the bootstrap sample for estimation of the covariance of the regression parameters consisting of the optimal bias and Lagrange multipliers. Experimental results are then presented which indicate the performance of this algorithm.

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Separate Fuzzy Regression with Fuzzy Input and Output

  • Choi, Seung-Hoe
    • Communications for Statistical Applications and Methods
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    • v.14 no.1
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    • pp.183-193
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    • 2007
  • This paper shows that a response function for the center of fuzzy output nay not be the same as that for the spread in a fuzzy linear regression model and then suggests a separate fuzzy regression model makes a distinction between response functions of the center and the spread of fuzzy output. Also we use a least squares method to estimate the separate fuzzy regression model and compare an accuracy of proposed model with another fuzzy regression model developed by Diamond (1988) and Kao and Chyu (2003).

ON THE CONSTRUCTION OF A SURFACE FROM DISCRETE DERIVATIVE DATA AND ITS EXTENDED SURFACE USING THE LEAST SQUARES METHOD

  • Kim, Hoi-Sub
    • Journal of applied mathematics & informatics
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    • v.4 no.2
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    • pp.387-396
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    • 1997
  • For given discrete derivative data in a rectangular re-gion we propose a method to generate an approximated surface which fits the given derivative data in the region and extends smoothly to a sufficiently large rectangular region. Such an extension in nec-essary in the generation of the surface in NC(numerical control) ma-chine.

NONCONFORMING SPECTRAL ELEMENT METHOD FOR ELASTICITY INTERFACE PROBLEMS

  • Kumar, N. Kishore
    • Journal of applied mathematics & informatics
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    • v.32 no.5_6
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    • pp.761-781
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    • 2014
  • An exponentially accurate nonconforming spectral element method for elasticity systems with discontinuities in the coefficients and the flux across the interface is proposed in this paper. The method is least-squares spectral element method. The jump in the flux across the interface is incorporated (in appropriate Sobolev norm) in the functional to be minimized. The interface is resolved exactly using blending elements. The solution is obtained by the preconditioned conjugate gradient method. The numerical solution for different examples with discontinuous coefficients and non-homogeneous jump in the flux across the interface are presented to show the efficiency of the proposed method.

Blockwise analysis for solving linear systems of equations

  • Smoktunowicz, Alicja
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.3 no.1
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    • pp.31-41
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    • 1999
  • We investigate some techniques of iterative refinement of solutions of a nonsingular system Ax = b with A partitioned into blocks using only single precision arithmetic. We prove that iterative refinement improves a blockwise measure of backward stability. Some applications of the results for the least squares problem (LS) will be also considered.

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MULTIGRID METHODS FOR THE PURE TRACTION PROBLEM OF LINEAR ELASTICITY: FOSLS FORMULATION

  • Lee, Chang-Ock
    • Communications of the Korean Mathematical Society
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    • v.12 no.3
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    • pp.813-827
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    • 1997
  • Multigrid methods for two first-order system least squares (FOSLS) using bilinear finite elements are developed for the pure traction problem of planar linear elasticity. They are two-stage algorithms that first solve for the gradients of displacement, then for the displacement itself. In this paper, concentration is given on solving for the gradients of displacement only. Numerical results show that the convergences are uniform even as the material becomes nearly incompressible. Computations for convergence rates are included.

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Biased-Recovering Algorithm to Solve a Highly Correlated Data System (상관관계가 강한 독립변수들을 포함한 데이터 시스템 분석을 위한 편차 - 복구 알고리듬)

  • 이미영
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.3
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    • pp.61-66
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    • 2003
  • In many multiple regression analyses, the “multi-collinearity” problem arises since some independent variables are highly correlated with each other. Practically, the Ridge regression method is often adopted to deal with the problems resulting from multi-collinearity. We propose a better alternative method using iteration to obtain an exact least squares estimator. We prove the solvability of the proposed algorithm mathematically and then compare our method with the traditional one.