• Title/Summary/Keyword: matrix comparison

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A new approach to model reduction using matrix pencil method (Matrix Pencil을 이용한 모델 저차화의 새로운 접근방법)

  • 권혁성;정정주;서병설
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.105-108
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    • 1997
  • This paper proposes a new approach of balanced model reduction using matrix pencil. The algorithm presented in this paper is to convert full-rank high-order system into rank-deficient system using perturbation made by matrix pencil method. Then the system can be truncated to a low-order system that we want via balanced realization. We discuss the comparison with other methods and the various observations by simulations.

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A VARIANT OF BLOCK INCOMPLETE FACTORIZATION PRECONDITIONERS FOR A SYMMETRIC H-MATRIX

  • Yun, Jae-Heon;Kim, Sang-Wook
    • Journal of applied mathematics & informatics
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    • v.8 no.3
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    • pp.705-720
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    • 2001
  • We propose a variant of parallel block incomplete factorization preconditioners for a symmetric block-tridiagonal H-matrix. Theoretical properties of these block preconditioners are compared with those of block incomplete factoriztion preconditioners for the corresponding somparison matrix. Numerical results of the preconditioned CG(PCG) method using these block preconditioners are compared with those of PCG using other types of block incomplete factorization preconditioners. Lastly, parallel computations of the block incomplete factorization preconditioners are carried out on the Cray C90.

PERFORMANCE COMPARISON OF PRECONDITIONED ITERATIVE METHODS WITH DIRECT PRECONDITIONERS

  • Yun, Jae Heon;Lim, Hyo Jin;Kim, Kyoum Sun
    • Journal of applied mathematics & informatics
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    • v.32 no.3_4
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    • pp.389-403
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    • 2014
  • In this paper, we first provide comparison results of preconditioned AOR methods with direct preconditioners $I+{\beta}L$, $I+{\beta}U$ and $I+{\beta}(L+U)$ for solving a linear system whose coefficient matrix is a large sparse irreducible L-matrix, where ${\beta}$ > 0. Next we propose how to find a near optimal parameter ${\beta}$ for which Krylov subspace method with these direct preconditioners performs nearly best. Lastly numerical experiments are provided to compare the performance of preconditioned iterative methods and to illustrate the theoretical results.

PRECONDITIONED AOR ITERATIVE METHOD FOR Z-MATRICES

  • Wang, Guangbin;Zhang, Ning;Tan, Fuping
    • Journal of applied mathematics & informatics
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    • v.28 no.5_6
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    • pp.1409-1418
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    • 2010
  • In this paper, we present a preconditioned iterative method for solving linear systems Ax = b, where A is a Z-matrix. We give some comparison theorems to show that the rate of convergence of the new preconditioned iterative method is faster than the rate of convergence of the previous preconditioned iterative method. Finally, we give one numerical example to show that our results are true.

Adjustment of Precise Triangulation Nets by Matrix Analysis (Matrix해석에 의한 엄밀3각망의 조정)

  • 이계학
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.6 no.2
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    • pp.28-33
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    • 1988
  • The objective of this work is to study the sue of precise triangulation nets by matrix analysis in adjusting coordinates. Results of this work show that matrix analysis has many advantages, namely in terms of accuracy and efficiency. In addition to this, comparison of adjusted vlues by two different methods, a Rigorous Method and an Approximate Method, show that differences in adjusted coordinates are 1-2 mm within the mean square error. This proves that the Approximate Method has sufficient accuracy in the practical application.

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Comparison of Wear Property Between Metal and Polymer Matrix Composites (금속복합재료와 고분자복합재료의 마모 특성 비교)

  • KIM, Jae-Dong
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.6
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    • pp.1875-1881
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    • 2016
  • The wear behavior for the two types of composites, those are epoxy matrix composites filled with silica particles and aluminium matrix composites filled with SiC particles, were compared to investigate the wear mechanism for these composites. Especially, the effect of the volume fraction for the epoxy matrix composites and the particle size for the aluminium matrix composites according to the apply load and sliding velocity were investigated. Wear tests of the pin-on-disc mode were carried out and followed by scanning electron microscope observations for the worn surface. The addition of the fillers in the composites were improved the wear resistance significantly and changed the wear mechanism for the both composites. These results were identified by the observation of the worn surface after testing.

Modified Phillips-Tikhonov regularization for plasma image reconstruction with modified Laplacian matrix

  • Jang, Si-Won;Lee, Seung-Heon;Choe, Won-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.472-472
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    • 2010
  • The tomography has played a key role in tokamak plasma diagnostics for image reconstruction. The Phillips-Tikhonov (P-T) regularization method was attempted in this work to reconstruct cross-sectional phantom images of the plasma by minimizing the gradient between adjacent pixel data. Recent studies about the comparison of the several tomographic reconstruction methods showed that the P-T method produced more accurate results. We have studied existing Laplacian matrix used in Phillips-Tikhonov regularization method and developed modified Laplacian matrix (Modified L). The comparison of the reconstruction result by the modified L and existing L showed that modified L produced more accurate result. The difference was significantly pronounced when a portion of plasma was reconstructed. These results can be utilized in the Edge Plasma diagnostics; especially in divertor diagnostics on tokamak a large impact is expected. In addition, accurate reconstruction results from received data in only one direction were confirmed through phantom test by using P-T method with modified L. These results can be applied to the tangentially viewing pin-hole camera diagnostics on tokamak.

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A Novel Current Steering Cell Matrix DAC Architecture with Reduced Decoder Area (디코더 면적을 줄이는 새로운 전류구동 셀 매트릭스 DAC 구조)

  • Jeong, Sang-Hun;Shin, Hong-Gyu;Cho, Seong-Ik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.3
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    • pp.627-631
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    • 2009
  • This paper presents a novel current steering cell matrix DAC(digital-to-analog converter) architecture to reduce decoder area. The current cell matrix of a existing architecture is selected by columns and lows thermometer code decoder of input bits. But The current cell matrix of a proposal architecture is divided 2n by the thermometer code decoder of upper input bits and are selected by the thermometer code decoder of middle and lower input bits. Because of this configuration, decoder numbers have increased. But the gate number that composed of decoder has decreased. In case of the designed 8 bit current steering cell matrix DAC, the gate number of decoder has decreased by about 55% in comparison with a existing architecture.