• Title/Summary/Keyword: Taylor

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Performance Comparison of Taylor Series Approximation and CORDIC Algorithm for an Open-Loop Polar Transmitter (Open-Loop Polar Transmitter에 적용 가능한 테일러 급수 근사식과 CORDIC 기법 성능 비교 및 평가)

  • Kim, Sun-Ho;Im, Sung-Bin
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.9
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    • pp.1-8
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    • 2010
  • A digital phase wrapping modulation (DPM) open-loop polar transmitter can be efficiently applied to a wideband orthogonal frequency division multiplexing (OFDM) communication system by converting in-phase and quadrature signals to envelope and phase signals and then employing the signal mapping process. This mapping process is very similar to quantization in a general communication system, and when taking into account the error that appears during mapping process, one can replace the coordinates rotation digital computer (CORDIC) algorithm in the coordinate conversion part with the Taylor series approximation method. In this paper, we investigate the application of the Taylor series approximation to the cartesian to polar coordinate conversion part of a DPM polar transmitter for wideband OFDM systems. The conventional approach relies on the CORDIC algorithm. To achieve efficient application, we perform computer simulation to measure mean square error (MSE) of the both approaches and find the minimum approximation order for the Taylor series approximation compatible to allowable error of the CORDIC algorithm in terms of hardware design. Furthermore, comparing the processing speeds of the both approaches in the implementation with FPGA reveals that the Taylor series approximation with lower order improves the processing speed in the coordinate conversion part.

A HIGHER ORDER ITERATIVE ALGORITHM FOR MULTIVARIATE OPTIMIZATION PROBLEM

  • Chakraborty, Suvra Kanti;Panda, Geetanjali
    • Journal of applied mathematics & informatics
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    • v.32 no.5_6
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    • pp.747-760
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    • 2014
  • In this paper a higher order iterative algorithm is developed for an unconstrained multivariate optimization problem. Taylor expansion of matrix valued function is used to prove the cubic order convergence of the proposed algorithm. The methodology is supported with numerical and graphical illustration.

Case Deletion Diagnostics for Intraclass Correlation Model

  • Kim, Myung Geun
    • Communications for Statistical Applications and Methods
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    • v.21 no.3
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    • pp.253-260
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    • 2014
  • The intraclass correlation model has a long history of applications in several fields of research. Case deletion diagnostic methods for the intraclass correlation model are proposed. Based on the likelihood equations, we derive a formula for a case deletion diagnostic method which enables us to investigate the influence of observations on the maximum likelihood estimates of the model parameters. Using the Taylor series expansion we develop an approximation to the likelihood distance. Numerical examples are provided for illustration.

FURTHER EXPANSION AND SUMMATION FORMULAS INVOLVING THE HYPERHARMONIC FUNCTION

  • Gaboury, Sebastien
    • Communications of the Korean Mathematical Society
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    • v.29 no.2
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    • pp.269-283
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    • 2014
  • The aim of the paper is to present several new relationships involving the hyperharmonic function introduced by Mez$\ddot{o}$ in (I. Mez$\ddot{o}$, Analytic extension of hyperharmonic numbers, Online J. Anal. Comb. 4, 2009) which is an analytic extension of the hyperharmonic numbers. These relations are obtained by using some fractional calculus theorems as Leibniz rules and Taylor like series expansions.

ON THE TAYLOR-BOWDER SPECTRUM

  • Jeon, In-Ho;Lee, Woo-Young
    • Communications of the Korean Mathematical Society
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    • v.11 no.4
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    • pp.997-1002
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    • 1996
  • In this paper we extend the Zemanek's characterization of the Browder spectrum for a commuting n-tuple operators in $L(H)$ and show that if $T = (T_1, \cdots, T_n)$ is Browder then there exists an n-tuple $K = (K_1, \cdots, K_n)$ of compact operators and an invertible commuting n-tuple $(S_1, \cdots, S_n)$ for which $T = S + K$ and $S_i K_j = K_j S_i$ for all $1 \leq i, j \leq n$.

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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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Influence of Flame Instabilities on Propagation Characteristics of Stagnating Turbulent Premixed Flames (화염 불안정성이 난류 예혼합 화염의 전파 특성에 미치는 영향에 관한 연구)

  • Kwon, Jaesung;Huh, Kang Y.
    • 한국연소학회:학술대회논문집
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    • 2012.04a
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    • pp.287-288
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    • 2012
  • DNS is performed to examine the propagation characteristics of stagnating turbulent premixed flames. Results show good agreement with the recently proposed relationship for turbulent burning velocity, $S_T$. It is shown that $S_T$ increases through a thinner flamelet, turbulence production and correlation between fluctuating velocity and buoyancy force respectively for diffusive-thermal, hydrodynamic and Rayleigh-Taylor instability. The mean curvature doesn't have significant effect on $S_T$ at the leading edge.

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A Generalized Finite Difference Method for Crack Analysis (일반화된 유한차분법을 이용한 균열해석)

  • Yoon, Young-Cheol;Kim, Dong-Jo;Lee, Sang-Ho
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.501-506
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    • 2007
  • A generalized finite difference method for solving solid mechanics problems such as elasticity and crack problems is presented. The method is constructed in framework of Taylor polynomial based on the Moving Least Squares method and collocation scheme based on the diffuse derivative approximation. The governing equations are discretized into the difference equations and the nodal solutions are obtained by solving the system of equations. Numerical examples successfully demonstrate the robustness and efficiency of the proposed method.

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Efficient Technique of Motion Vector Re-estimation in Transcoding (트랜스 코딩에서의 효율적인 움직임 벡터 재추정 기법 연구)

  • 한두진;박강서;유희준;김봉곤;박상희
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.8
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    • pp.602-605
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    • 2004
  • A novel motion vector re-estimation technique for transcoding into lower spatial resolution is proposed. This technique is based on the fact that the block matching error is proportional to the complexity of the reference block with Taylor series expansion. It is shown that the motion vectors re-estimated by the proposed method are closer to optimal ones and offer better quality than those of previous techniques.