• 제목/요약/키워드: Newton-Raphson

검색결과 588건 처리시간 0.022초

비선형 함수 연산을 위한 FPGA 기반의 부동 소수점 프로세서의 설계 (Design of a Floating Point Processor for Nonlinear Functions on an Embedded FPGA)

  • 김정섭;정슬
    • 대한임베디드공학회논문지
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    • 제3권4호
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    • pp.251-259
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    • 2008
  • This paper presents the hardware design of a 32bit floating point based processor. The processor can perform nonlinear functions such as sinusoidal functions, exponential functions, and other mathematical functions. Using the Taylor series and Newton - Raphson method, nonlinear functions are approximated. The processor is actually embedded on an FPGA chip and tested. The numerical accuracy of the functions is compared with those computed by the MATLAB and confirmed the performance of the processor.

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Quasi-Likelihood Approach for Linear Models with Censored Data

  • Ha, Il-Do;Cho, Geon-Ho
    • Journal of the Korean Data and Information Science Society
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    • 제9권2호
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    • pp.219-225
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    • 1998
  • The parameters in linear models with censored normal responses are usually estimated by the iterative maximum likelihood and least square methods. However, the iterative least square method is simple but hardly has theoretical justification, and the iterative maximum likelihood estimating equations are complicatedly derived. In this paper, we justify these methods via Wedderburn (1974)'s quasi-likelihood approach. This provides an explicit justification for the iterative least square method and also directly the iterative maximum likelihood method for estimating the regression coefficients.

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Statistical Estimation for Generalized Logit Model of Nominal Type with Bootstrap Method

  • Cho, Joong-Jae;Han, Jeong-Hye
    • Journal of the Korean Statistical Society
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    • 제24권1호
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    • pp.1-18
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    • 1995
  • The generalized logit model of nominal type with random regressors is studied for bootstrapping. In particular, asymptotic normality and consistency of bootstrap model estimators are derived. It is shown that the bootstrap approximation to the distribution of the maximum likelihood estimators is valid for alsomt all sample sequences.

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SMALL SAMPLE PROPERTIES OF GENERALIZED LOGIT MODEL ESTIMATORS WITH BOOTSTRAP

  • Kim, Peyong-Koo;Kim, Jong-Ho;Cho, Joong-Jae
    • Journal of applied mathematics & informatics
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    • 제3권2호
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    • pp.253-264
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    • 1996
  • The generalized logit model of nominal type with random regressors is studied for bootstrapping. We assess the accuracy of some estimators for our generalized logit model using a Monte Carlo simu-lation. That is we study the finite sample properties containing the consistency and asymptotic normality of the maximum likelihood es-timators. Also we compare Newton Raphson algorithm with BHHH algorithm.

비대칭형 PWM 교류쵸퍼의 기본파 전압제어 및 고조파 전압제거 (Asymmetrical PWM Technique with Fundamental Voltage Control and Harmonic Voltage Elimnation in AC Choppers)

  • 장도현;최규하
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 B
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    • pp.1067-1070
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    • 1992
  • Optimal Asymmetrical Pulse-width Modulated (APWM) technique for ac chopper is proposed which can improve the input power factor and eliminate the harmonics of output voltage up to a specified order, and also enables linear control of the fundamental component of the output voltage. The PWM switching patterns at the specified phase angle are obtained by Newton-Raphson method and theoretical comparisons are made with other PWM and APWM technique.

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탄성 경계상 압착막에 대한 미끄럼 속도의 영향 (Some Effects of Sliding Velocity on The Elastohydrodynamic Squeeze Films)

  • 유형선;이병철
    • Tribology and Lubricants
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    • 제2권1호
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    • pp.46-52
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    • 1986
  • 얇은 유막위의 타이어 변형해석이나, 압착막댐퍼 설계등의 해석에 응용되는 변동 하중하의 탄성 경계상 유체 압착막의 해석을 Newton-Raphson 반복법을 사용하여 하였다. 유막두께의 계산은 등계수 요소를 사용하여 정확한 계산을 하였고 슬라이더의 궤적은 강쇄진동의 응답곡선과 유사함을 알 수 있었다. 특히 본 연구에서는 미끄럼 속도의 영향을 고려하였으며 유체가 베어링내에 생긴 포켓에 정체하고 있어서 미끄럼의 영향은 속도가 클때를 제외하고는 큰 영향을 미치지 못함을 알 수 있었다.

Solids 3-D with bounded tensile strength under the action of thermal strains. Theoretical aspects and numerical procedures

  • Pimpinelli, Giovanni
    • Structural Engineering and Mechanics
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    • 제18권1호
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    • pp.59-78
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    • 2004
  • This paper is devoted to illustrate some numerical procedures to solve the boundary equilibrium problems of three-dimensional solids that are subjected to thermal strains. The constitutive equations take into account the bounded tensile strength of the material and they are presented in the framework of non-linear elasticity and small strains. The associated equilibrium problem is solved numerically by means of the finite element method and the numerical techniques, i.e. the Newton-Raphson method and the secant method, are revised in order to assure the solution convergence of the discretized problem. Some numerical examples are illustrated.

A Transient stability Analysis Algorithm Using decoupled Network Solution

  • Park, Young-Moon;Park, Jong-Bae
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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    • pp.135-139
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    • 1988
  • This paper presents a new algorithm using power flow solution which is given by the polar form Newton-Raphson method in a transient stability analysis. The computation time to solve network equations can be much saved by a decoupled power flow method. In addition, the time is much saved in performing a approximate stability analysis by linearizing the differential equations and using a voltage and angle sensitivity matrix given in network equations.

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BTX제조공정의 모사연구 (Simulation of Benzene-Toluene-Xylene Plant)

  • 정해동
    • 한국시뮬레이션학회논문지
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    • 제4권1호
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    • pp.121-130
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    • 1995
  • This paper deals with modeling and simulation of an industrial benzene-toluene-xylene plant. Because the fractionation unit of benzene-toluene-xylene plant has a narrow range of boiling point and doesn't have any sidecut and side reboiler, we employed boiling point estimation method in the modeling and simulation of the plant. Soave-Redlich-Kwong equation was used in the computation of thermodynamical properties. We solved resulting nonlinear equations by using Newton-Raphson method which is known to show fast convergence. Results of simulation showed good agreement with actual plant operation data.

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로보트 매니퓰레이터 운동의 컴퓨터 시뮬레이션 시스템 (Computer simulation system of robot manipulator motion)

  • 김창부;윤장로
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.539-544
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    • 1991
  • In order to verify robot motions for a desired work, it is necessary to visualize it on a computer screen. This paper presents a simulation algorithm for robot manipulator motion. Kinematic description is based on the Denavit- Hartenberg link representation. In order to be applied to various types of the robot manipulator, inverse kinematics make use of the Newton-Raphson iterative method with the least squares method. Joint variables are interpolated by the lowest polynomial segment satisfying acceleration continuity. The robot motions are generated and then animated on a computer screen in the form of skeleton type.

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