• 제목/요약/키워드: Nonlinear Approximation

검색결과 560건 처리시간 0.029초

적응형 확장 칼만 필터를 이용한 항공기의 비선형 상태추정 (The Nonlinear State Estimation of the Aircraft using the Adaptive Extended Kalman Filter)

  • Jong Chul Kim;Sang Jong Lee;Anatol A. Tunik
    • 제어로봇시스템학회논문지
    • /
    • 제5권2호
    • /
    • pp.158-165
    • /
    • 1999
  • 비행시험을 통해 획득한 데이터의 해석과정에서 대상 항공기의 크기가 소형인 경우에는 엔진진동이나 외부의 교란에 의한 잡음이나 바이어스 등의 강도가 높기 때문에 데이터의 처리과정에서 많은 문제점을 산출하게 된다. 이와 같은 문제점을 해결하기 위해 상태추정 알고리즘이 사용되며, 본 논문에서는 항공기의 비선형 세로운동 방정식의 경우에 확장형 칼만 필터를 적용하여 항공기 세로운동의 상태변수들을 추정하였으며, 또한 확률근사과정, 이노베이션에 대한 궤환 적응 등 적응형 칼만 필터를 사용하여 수렴속도와 정확도 둥을 향상시킨 알고리즘을 제안하고 그 결과를 나타내었다.

  • PDF

AUXILIARY PRINCEPLE AND ERROR ESTIMATES FOR VARIATIONAL INEQUALITIES

  • NOOR, MUHAMMED ASLAM
    • 호남수학학술지
    • /
    • 제15권1호
    • /
    • pp.105-120
    • /
    • 1993
  • The auxiliary principle technique is used to prove the uniqueness and the existence of solutions for a class of nonlinear variational inequalities and suggest an innovative iterative algorithm for computing the approximate solution of variational inequalities. Error estimates for the finite element approximation of the solution of variational inequalities are derived, which refine the previous known results. An example is given to illustrate the applications of the results obtained. Several special cases are considered and studied.

  • PDF

로봇부하 구동용 브러시 DC 모터의 적응 퍼지 백 스테핑 제어기 설계 (Design of an Adaptive Fuzzy Backstepping Controller for a Brush DC Motor Turning a Robotic Load)

  • 김영태
    • 한국정밀공학회지
    • /
    • 제23권9호
    • /
    • pp.92-101
    • /
    • 2006
  • In this paper a adaptive backstepping control scheme is proposed for control of a do motor driving a one-link manipulator. Fuzzy logic systems are used to approximate the unknown nonlinear function including the parametric uncertainty and disturbance throughout the entire electromechanical system. A compensation controller is also proposed to estimate the bound of approximation error. Thus the asymptotic stability of the closed-loop control system can be obtained. Numerical simulations are included to show the effectiveness of the proposed controller.

A DISCRETE FINITE ELEMENT GALERKIN METHOD FOR A UNIDIMENSIONAL SINGLE-PHASE STEFAN PROBLEM

  • Lee, Hyun-Young
    • Journal of applied mathematics & informatics
    • /
    • 제16권1_2호
    • /
    • pp.165-181
    • /
    • 2004
  • Based on Landau-type transformation, a Stefan problem with non-linear free boundary condition is transformed into a system consisting of parabolic equation and the ordinary differential equations. Semidiscrete approximations are constructed. Optimal orders of convergence of semidiscrete approximation in $L_2$, $H^1$ and $H^2$ normed spaces are derived.

WAVENET을 이용한 비선형 시스템의 제어 (Control of Nonlinear System using WAVENET)

  • 박두환;김경엽;이준탁
    • 한국마린엔지니어링학회:학술대회논문집
    • /
    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
    • /
    • pp.257-261
    • /
    • 2005
  • The helicopter system is non-linear and complex. Futhermore, because of absence of accurate mathematical model, it is difficult accurately to control its attitude. therefore, we propose a WAVENET control technique to control efficiently its elevation angle and azimuth one. Wavelet neural network(WAVENET) can construct systematically initial neural network as applying wavelet theory to feedforward network. It is proved through computer simulation that WAVENET has more excellent approximation capability than existing neural network. The simulation results using MATLAB are introduced.

  • PDF

의사 결정 구조에 의한 오존 농도예측 (Forecasting Ozone Concentration with Decision Support System)

  • 김재용;김태헌;김성신;이종범;김신도;김용국
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
    • /
    • pp.368-368
    • /
    • 2000
  • In this paper, we present forecasting ozone concentration with decision support system. Since the mechanism of ozone concentration is highly complex, nonlinear, and nonstationary, modeling of ozone prediction system has many problems and results of prediction are not good performance so far. Forecasting ozone concentration with decision support system is acquired to information from human knowledge and experiment data. Fuzzy clustering method uses the acquisition and dynamic polynomial neural network gives us a good performance for ozone prediction with ability of superior data approximation and self-organization.

  • PDF

광대역통신망의 링크용량 설계 모형 및 알고리듬 (Model and Algorithm for Link Dimensioning of B-ISDN)

  • 주종혁
    • 산업경영시스템학회지
    • /
    • 제22권51호
    • /
    • pp.99-108
    • /
    • 1999
  • B-ISDN link dimensioning is often known as a difficult problem because of the characteristics of Asynchronous Transfer Mode(ATM) such as various Quality of Services of different service requirements, and the statistical multiplexing resulting from virtual path/virtual circuit connections. In this paper, we propose a nonlinear integer optimization model for dimensioning B-ISDN considering the statistical multiplexing effects of virtual path connections(VPCs) and the modularity of resources allocated to a transmission link. The algorithm based on the simultaneous linear approximation technique as well as some numerical results will be also presented.

  • PDF

RBF 신경망을 이용한 비선형 근사 (Nonlinear Approximations Using RBF Neural Networks)

  • 박주영
    • 한국지능시스템학회논문지
    • /
    • 제6권2호
    • /
    • pp.26-35
    • /
    • 1996
  • In this paper, some fundamental problems concerning RBF(radial-basis-function) networks and approximation of functions are addressed. First, a comprehensive introduction to RBF networks is given with typical RBF networks classified into three classes. Next, sharp conditions are given under which continuous functions of a finite number of real variables can be approximated arbitrarily well by a certain class of RBF networks. Finally, a related result is given concerning the representation of functions in the form of distributed RBF networks.

  • PDF

THE CONVERGENCE OF HOMOTOPY METHODS FOR NONLINEAR KLEIN-GORDON EQUATION

  • Behzadi, Shadan Sadigh
    • Journal of applied mathematics & informatics
    • /
    • 제28권5_6호
    • /
    • pp.1227-1237
    • /
    • 2010
  • In this paper, a Klein-Gordon equation is solved by using the homotopy analysis method (HAM), homotopy perturbation method (HPM) and modified homotopy perturbation method (MHPM). The approximation solution of this equation is calculated in the form of series which its components are computed easily. The uniqueness of the solution and the convergence of the proposed methods are proved. The accuracy of these methods are compared by solving an example.

Computational Solution of a H-J-B equation arising from Stochastic Optimal Control Problem

  • Park, Wan-Sik
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
    • /
    • pp.440-444
    • /
    • 1998
  • In this paper, we consider numerical solution of a H-J-B (Hamilton-Jacobi-Bellman) equation of elliptic type arising from the stochastic control problem. For the numerical solution of the equation, we take an approach involving contraction mapping and finite difference approximation. We choose the It(equation omitted) type stochastic differential equation as the dynamic system concerned. The numerical method of solution is validated computationally by using the constructed test case. Map of optimal controls is obtained through the numerical solution process of the equation. We also show how the method applies by taking a simple example of nonlinear spacecraft control.

  • PDF