• Title/Summary/Keyword: Newton-Raphson Method

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A Predicted Newton-Raphson Iterative Method utilizing Neural Network (신경회로망을 이용한 예측 뉴턴-랩손 반복계산기법)

  • Kim, Jong-Hoon;Kim, Yong-Hyup
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.339-344
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    • 2000
  • Newton-Raphson 기법은 구조물의 비선형 해석에 널리 쓰이는 반복계산기법이다. 비선형 해석을 위한 반복계산기법은 컴퓨터의 발달을 감안해도 상당한 계산시간이 소요된다. 본 논문에서는 신경회로망 예측을 사용한 Predicted Newton-Raphson 반복계산기법을 제안하였다. 통상적인 Newton-Raphson 기법은 이전스텝에서 수렴된 점으로부터 현재 스텝의 반복계산을 시작하는 반면 제시된 방법은 현재 스텝 수렴해에 대한 예측점에서 반복계산을 시작한다. 수렴해에 대한 예측은 신경회로망을 사용하여 이전 스텝 수렴해의 과거경향을 파악한 후 구한다. 반복계산 시작점이 수렴점에 보다 근접하여 위치하므로 수렴속도가 빨라지게 되고 허용되는 하중스텝의 크기가 커지게 된다. 또한 반복계산의 시작점으로부터 이루어지는 계산과정은 통상적인 Newton-Raphson 기법과 동일하므로 기존의 Newton-Raphson 기법과 정확히 일치하는 수렴해를 구할 수 있다. 구조물의 정적 비선형 거동에 대한 수치해석을 통하여 modified Newton-Raphson 기법과 제시된 Predicted Newton=Raphson 기법의 정확성과 효율성을 비교하였다. 제시된 Predicted Newton-Raphson 기법은 modified Newton-Raphson 기법과 동일한 해를 산출하면서도 계산상의 효율성이 매우 큼을 확인할 수 있었다.

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Initial Point Optimization for Square Root Approximation based on Newton-Raphson Method (Newton-Raphson 방식의 제곱근 근사를 위한 초기값의 최적화)

  • Choi Chang-Soon;Lee Jin-Yong;Kim Young-Lok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.3 s.345
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    • pp.15-20
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    • 2006
  • A Newton-Raphson Method for table driven algorithm is presented in this paper. We concentrate the approximation of square root by using Newton-Raphson method. We confirm that this method has advantages of accurate and fast processing with optimized initial point. Hence the selection of the fitted initial points used in approximation of Newton-Raphson algorithm is important issue. This paper proposes that log scale based on geometric wean is most profitable initial point. It shows that the proposed method givemore accurate results with faster processing speed.

Structural Damage Identification by Using the Spectral Element Model and the Newton-Raphson Method (스텍트럴요소 모델과 Newton-Raphson 법을 이용한 구조손상규명)

  • Kim, Jung-Soo;Kwon, Kyung-Soo;Lee, U-Sik
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.921-926
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    • 2004
  • In this paper, a nonlinear structural damage identification algorithm is derived by taking into account the non-linearity of damage. The structural damage identification analyses are conducted by using the direct method and the Newton-Raphson method. It is found that, the Newton-Raphson method in general provides the better damage identification results when compared with the results obtained by the direct method.

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Quadratic Newton-Raphson Method for DC and Transient Analyses of Electronic Circuits (電子回路의 DC 및 過渡解析을 위한 2次 Newton-Raphson 方法)

  • Jun, Young-Hyun;Lee, Ki-Jun;Park, Song-Bai
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.1
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    • pp.122-128
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    • 1989
  • In this paper we propose a new method for solving a set of nonlinear algebraic equations encountered in the DC and transient analyses of electronic circuits. This method will be called Quadratic Newton-Raphson Method (QNRM), since it is based on the Newton-Raphson Method (NRM) but effectively takes into accoujnt the second order derivative terms in the Taylor series expansion of the nonlinear algebraic equations. The second order terms are approximated by linear terms using a carefully estimated solution at each iteration. Preliminary simulation results show that the QNRM saves the overall computational time significantly in the DC and transient analysis, compared with the conventional NRM.

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Time Variant Parameter Estimation using RLS Algorithm with Adaptive Forgetting Factor Based on Newton-Raphson Method (Newton-Raphson법 기반의 적응 망각율을 갖는 RLS 알고리즘에 의한 원격센서시스템의 시변파라메타 추정)

  • Kim, Kyung-Yup;Lee, Joon-Tark
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2007.04a
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    • pp.435-439
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    • 2007
  • This paper deals with RLS algorithm using Newton-Raphson method based adaptive forgetting factor for a passive telemetry RF sensor system in order to estimate the time variant parameter to be included in RF sensor model. For this estimation with RLS algorithm, phasor typed RF sensor system modelled with inductive coupling principle is used. Instead of applying constant forgetting factor to estimate time variant parameter, the adaptive forgetting factor based on Newton-Raphson method is applied to RLS algorithm without constant forgetting factor to be determined intuitively. Finally, we provide numerical examples to evaluate the feasibility and generality of the proposed method in this paper.

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NEWTON-RAPHSON METHOD FOR COMPUTING p-ADIC ROOTS

  • Yeo, Gwangoo;Park, Seong-Jin;Kim, Young-Hee
    • Journal of the Chungcheong Mathematical Society
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    • v.28 no.4
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    • pp.575-582
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    • 2015
  • The Newton-Raphson method is used to compute the q-th roots of a p-adic number for a prime number q. The sufficient conditions for the convergence of this method are obtained. The speed of its convergence and the number of iterations to obtain a number of corrected digits in the approximation are calculated.

Impedance Imaging of Binary-Mixture Systems with Regularized Newton-Raphson Method

  • Kim, Min-Chan;Kim, Sin;Kim, Kyung-Youn
    • Journal of Energy Engineering
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    • v.10 no.3
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    • pp.183-187
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    • 2001
  • Impedance imaging for binary mixture is a kind of nonlinear inverse problem, which is usually solved iteratively by the Newton-Raphson method. Then, the ill-posedness of Hessian matrix often requires the use of a regularization method to stabilize the solution. In this study, the Levenberg-Marquredt regularization method is introduced for the binary-mixture system with various resistivity contrasts (1:2∼1:1000). Several mixture distribution are tested and the results show that the Newton-Raphson iteration combined with the Levenberg-Marquardt regularization can reconstruct reasonably good images.

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A Study on the load Flow Calculation for preserving off Diagonal Element in Jacobian Matrix (Jacobian 행렬의 비 대각 요소를 보존시킬 수 있는 조류계산에 관한 연구)

  • 이종기;최병곤;박정도;류헌수;문영현
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.9
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    • pp.1081-1087
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    • 1999
  • Load Flow calulation methods can usually be divided into Gauss-Seidel method, Newton-Raphson method and decoupled method. Load flow calculation is a basic on-line or off-line process for power system planning. operation, control and state analysis. These days Newton-Raphson method is mainly used since it shows remarkable convergence characteristics. It, however, needs considerable calculation time in construction and calculation of inverse Jacobian matrix. In addition to that, Newton-Raphson method tends to fail to converge when system loading is heavy and system has a large R/X ratio. In this paper, matrix equation is used to make algebraic expression and then to slove load flow equation and to modify above defects. And it preserve P-Q bus part of Jacobian matrix to shorten computing time. Application of mentioned algorithm to 14 bus, 39 bus, 118 bus systems led to identical results and the same numbers of iteration obtained by Newton-Raphson method. The effect of computing time reduction showed about 28% , 30% , at each case of 39 bus, 118 bus system.

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A Fast Forward Kinematic Analysis of Stewart Platform (스튜어트 플랫폼의 빠른 순기구학 해석)

  • Ha, Hyeon-Pyo;Han, Myeong-Cheol
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.25 no.3
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    • pp.339-352
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    • 2001
  • The inverse kinematics problem of Stewart platform is straightforward, but no closed form solution of the forward kinematic problem has been presented. Since we need the real-time forward kinematic solution in MIMO control and the motion monitoring of the platform, it is important to acquire the 6 DOF displacements of the platform from measured lengths of six cylinders in small sampling period. Newton-Raphson method a simple algorithm and good convergence, but it takes too long calculation time. So we reduce 6 nonlinear kinematic equations to 3 polynomials using Nairs method and 3 polynomials to 2 polynomials. Then Newton-Raphson method is used to solve 3 polynomials and 2 polynomials respectively. We investigate operation counts and performance of three methods which come from the equation reduction and Newton-Raphson method, and choose the best method.