• Title/Summary/Keyword: Adaptive neural network

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Automatic Berthing Control of Ship Using Adaptive Neural Networks

  • Nguyen, Phung-Hung;Jung, Yun-Chul
    • Journal of Navigation and Port Research
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    • v.31 no.7
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    • pp.563-568
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    • 2007
  • In this paper, an adaptive neural network controller and its application to automatic berthing control of ship is presented. The neural network controller is trained online using adaptive interaction technique without any teaching data and off-line training phase. Firstly, the neural networks used to control rudder and propeller during automatic berthing process are presented. Secondly, computer simulations of automatic ship berthing are carried out in Pusan bay to verify the proposed controller under the influence of wind disturbance and measurement noise. The results of simulation show good performance of the developed berthing control system.

Direct Adaptive Control Based on Neural Networks Using An Adaptive Backpropagation Algorithm (적응 역전파 학습 알고리즘을 이용한 신경회로망 제어기 설계)

  • Choi, Kyoung-Mi;Choi, Yoon-Ho;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1730-1731
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    • 2007
  • In this paper, we present a direct adaptive control method using neural networks for the control of nonlinear systems. The weights of neural networks are trained by an adaptive backpropagation algorithm based on Lyapunov stability theory. We develop the parameter update-laws using the neural network input and the error between the desired output and the output of nonlinear plant to update the weights of a neural network in the sense that Lyapunove stability theory. Beside the output tracking error is asymptotically converged to zero.

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Characteristics Modeling of Dynamic Systems Using Adaptive Neural Computation (적응 뉴럴 컴퓨팅 방법을 이용한 동적 시스템의 특성 모델링)

  • Kim, Byoung-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.4
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    • pp.309-314
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    • 2007
  • This paper presents an adaptive neural computation algorithm for multi-layered neural networks which are applied to identify the characteristic function of dynamic systems. The main feature of the proposed algorithm is that the initial learning rate for the employed neural network is assigned systematically, and also the assigned learning rate can be adjusted empirically for effective neural leaning. By employing the approach, enhanced modeling of dynamic systems is possible. The effectiveness of this approach is veri tied by simulations.

Soft computing with neural networks for engineering applications: Fundamental issues and adaptive approaches

  • Ghaboussi, Jamshid;Wu, Xiping
    • Structural Engineering and Mechanics
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    • v.6 no.8
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    • pp.955-969
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    • 1998
  • Engineering problems are inherently imprecision tolerant. Biologically inspired soft computing methods are emerging as ideal tools for constructing intelligent engineering systems which employ approximate reasoning and exhibit imprecision tolerance. They also offer built-in mechanisms for dealing with uncertainty. The fundamental issues associated with engineering applications of the emerging soft computing methods are discussed, with emphasis on neural networks. A formalism for neural network representation is presented and recent developments on adaptive modeling of neural networks, specifically nested adaptive neural networks for constitutive modeling are discussed.

Nonlinear Prediction using Gamma Multilayered Neural Network (Gamma 다층 신경망을 이용한 비선형 적응예측)

  • Kim Jong-In;Go Il-Hwan;Choi Han-Go
    • Journal of the Institute of Convergence Signal Processing
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    • v.7 no.2
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    • pp.53-59
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    • 2006
  • Dynamic neural networks have been applied to diverse fields requiring temporal signal processing such as system identification and signal prediction. This paper proposes the gamma neural network(GAM), which uses gamma memory kernel in the hidden layer of feedforward multilayered network, to improve dynamics of networks and then describes nonlinear adaptive prediction using the proposed network as an adaptive filter. The proposed network is evaluated in nonlinear signal prediction and compared with feedforword(FNN) and recurrent neural networks(RNN) for the relative comparison of prediction performance. Simulation results show that the GAM network performs better with respect to the convergence speed and prediction accuracy, indicating that it can be a more effective prediction model than conventional multilayered networks in nonlinear prediction for nonstationary signals.

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Optical Implementation of Single-Layer Adaptive Neural Network for Multicategory Classification. (다영상 분류를 위한 단층 적응 신경회로망의 광학적 구현)

  • 이상훈
    • Proceedings of the Optical Society of Korea Conference
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    • 1991.06a
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    • pp.23-28
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    • 1991
  • A single-layer neural network with 4$\times$4 input neurons and 4 output neurons is optically implemented. Holographic lenslet arrays are used for the e optical interconnection topology, a liquid crystal light valve(LCLV) is used for controlling optical interconection weights. Using a Perceptron learning rule, it classifics input patterns into 4 different categories. It is shown that the performance of the adaptive neural network depends on the learning rate, the correlation of input patterns, and the nonlinear characteristic properties of the liquid crystal light valve.

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Friction Compensation For High Precision Control of Servo Systems Using Adaptive Neural Network

  • Chung, Dae-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.179-179
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    • 2000
  • An adaptive neural network compensator for stick-slip friction phenomena in servo systems is proposed to supplement the traditionally available position and velocity control loops for precise motion control. The neural network compensator plays a role of canceling the effect of nonlinear slipping friction force. This enables the mechatronic systems more precise control and realistic design in the digital computer. It was confirmed that the control accuracy is more improved near zero velocity and the points of changing the moving direction through numerical simulation

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Adaptive PID controller based on error self-recurrent neural networks (오차 자기순환 신경회로망에 기초한 적응 PID제어기)

  • Lee, Chang-Goo;Shin, Dong-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.4 no.2
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    • pp.209-214
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    • 1998
  • In this paper, we are dealing with the problem of controlling unknown nonlinear dynamical system by using neural networks. A novel error self-recurrent(ESR) neural model is presented to perform black-box identification. Through the various outcome of the experiment, a new neural network is seen to be considerably faster than the BP algorithm and has advantages of being less affected by poor initial weights and learning rate. These characteristics make it flexible to design the controller in real-time based on neural networks model. In addition, we design an adaptive PID controller that Keyser suggested by using ESR neural networks, and present a method on the implementation of adaptive controller based on neural network for practical applications. We obtained good results in the case of robot manipulator experiment.

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Design of an Adaptive Output Feedback Controller for Robot Manipulators Using DNP (DNP을 이용한 로봇 매니퓰레이터의 출력 궤환 적응제어기 설계)

  • Cho, Hyun-Seob
    • Proceedings of the KAIS Fall Conference
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    • 2008.11a
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    • pp.191-196
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    • 2008
  • The intent of this paper is to describe a neural network structure called dynamic neural processor(DNP), and examine how it can be used in developing a learning scheme for computing robot inverse kinematic transformations. The architecture and learning algorithm of the proposed dynamic neural network structure, the DNP, are described. Computer simulations are provided to demonstrate the effectiveness of the proposed learning using the DNP.

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Tool Breakage Detection in Face Milling Using a Self Organized Neural Network (자기구성 신경회로망을 이용한 면삭밀링에서의 공구파단검출)

  • 고태조;조동우
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.8
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    • pp.1939-1951
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    • 1994
  • This study introduces a new tool breakage detecting technology comprised of an unsupervised neural network combined with adaptive time series autoregressive(AR) model where parameters are estimated recursively at each sampling instant using a parameter adaptation algorithm based on an RLS(Recursive Least Square). Experiment indicates that AR parameters are good features for tool breakage, therefore it can be detected by tracking the evolution of the AR parameters during milling process. an ART 2(Adaptive Resonance Theory 2) neural network is used for clustering of tool states using these parameters and the network is capable of self organizing without supervised learning. This system operates successfully under the wide range of cutting conditions without a priori knowledge of the process, with fast monitoring time.