• Title/Summary/Keyword: Adaptive radial basis function network

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An Identification Technique Based on Adaptive Radial Basis Function Network for an Electronic Odor Sensing System

  • Byun, Hyung-Gi
    • Journal of Sensor Science and Technology
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    • v.20 no.3
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    • pp.151-155
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    • 2011
  • A variety of pattern recognition algorithms including neural networks may be applicable to the identification of odors. In this paper, an identification technique for an electronic odor sensing system applicable to wound state monitoring is presented. The performance of the radial basis function(RBF) network is highly dependent on the choice of centers and widths in basis function. For the fine tuning of centers and widths, those parameters are initialized by an ill-conditioned genetic fuzzy c-means algorithm, and the distribution of input patterns in the very first stage, the stochastic gradient(SG), is adapted. The adaptive RBF network with singular value decomposition(SVD), which provides additional adaptation capabilities to the RBF network, is used to process data from array-based gas sensors for early detection of wound infection in burn patients. The primary results indicate that infected patients can be distinguished from uninfected patients.

An Adaptive Neural Network Control Method for Robot Manipulators

  • Lee, Min-Jung;Choi, Young-Kiu
    • Proceedings of the KIEE Conference
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    • 2001.07d
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    • pp.2341-2344
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    • 2001
  • In recent years the neural network known as a sort of the intelligent control strategy is used as a powerful tool for designing control system since it has learning ability. But it is difficult for neural network controllers to guarantee the stability of control systems. In this paper we try connecting a radial basis function network to an adaptive control strategy. Radial basis function networks are simpler and easier to handle than multilayer perceptrons. We use the radial basis function network to generate control input signals that are similar to the control inputs of adaptive control using linear reparameterization of the robot manipulator. We adopt the saturation function as an auxiliary controller. This paper also proves mathematically the stability of the control system under the existence of disturbances and modeling errors.

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An Adaptive Control Method of Robot Manipulators using RBFN (RBFN을 이용한 로봇 매니퓰레이터의 적응제어 방법)

  • 이민중;최영규;박진현
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.420-420
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    • 2000
  • In this paper, we propose an adaptive controller using RBFN(radial basis function network) for robot manipulators The structure of the proposed controller consists of a RBFN and VSC-1 ike control. RBFN is used in order to approximate かon system, and VSC-like control to guarantee robustness On the basis of the Lyapunov stability theorem, we guarantee the stability for the total system. And the learning law of RBFN is established by the Lyapunov method, Finally, we apply the proposed controller to tracking control for a 2 link SCARA type robot manipulator.

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A study on EMG pattern recognition based on parallel radial basis function network (병렬 Radial Basis Function 회로망을 이용한 근전도 신호의 패턴 인식에 관한 연구)

  • Kim, Se-Hoon;Lee, Seung-Chul;Kim, Ji-Un;Park, Sang-Hui
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2448-2450
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    • 1998
  • For the exact classification of the arm motion this paper proposes EMG pattern recognition method with neural network. For this autoregressive coefficient, linear cepstrum coefficient, and adaptive cepstrum coefficient are selected for the feature parameter of EMG signal, and they are extracted from time series EMG signal. For the function recognition of the feature parameter a radial basis function network, a field of neural network is designed. For the improvement of recognition rate, a number of radial basis function network are combined in parallel, comparing with a backpropagation neural network an existing method.

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Equalizationof nonlinear digital satellite communicatio channels using a complex radial basis function network (Complex radial basis function network을 이용한 비선형 디지털 위성 통신 채널의 등화)

  • 신요안;윤병문;임영선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.9
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    • pp.2456-2469
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    • 1996
  • A digital satellite communication channel has a nonlinearity with memory due to saturation characeristis of the high poer amplifier in the satellite and transmitter/receiver linear filter used in the overall system. In this paper, we propose a complex radial basis function network(CRBFN) based adaptive equalizer for compensation of nonlinearities in digital satellite communication channels. The proposed CRBFN untilizes a complex-valued hybrid learning algorithm of k-means clustering and LMS(least mean sequare) algorithm that is an extension of Moody Darken's algorithm for real-valued data. We evaluate performance of CRBFN in terms of symbol error rates and mean squared errors nder various noise conditions for 4-PSK(phase shift keying) digital modulation schemes and compare with those of comples pth order inverse adaptive Volterra filter. The computer simulation results show that the proposed CRBFN ehibits good equalization, low computational complexity and fast learning capabilities.

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An Adaptive Radial Basis Function Network algorithm for nonlinear channel equalization

  • Kim Nam yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.3C
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    • pp.141-146
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    • 2005
  • The authors investigate the convergence speed problem of nonlinear adaptive equalization. Convergence constraints and time constant of radial basis function network using stochastic gradient (RBF-SG) algorithm is analyzed and a method of making time constant independent of hidden-node output power by using sample-by-sample node output power estimation is derived. The method for estimating the node power is to use a single-pole low-pass filter. It is shown by simulation that the proposed algorithm gives faster convergence and lower minimum MSE than the RBF-SG algorithm.

Adaptive Neural Network Control for Robot Manipulators

  • Lee, Min-Jung;Choi, Young-Kiu
    • KIEE International Transaction on Systems and Control
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    • v.12D no.1
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    • pp.43-50
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    • 2002
  • In the recent years neural networks have fulfilled the promise of providing model-free learning controllers for nonlinear systems; however, it is very difficult to guarantee the stability and robustness of neural network control systems. This paper proposes an adaptive neural network control for robot manipulators based on the radial basis function netwo.k (RBFN). The RBFN is a branch of the neural networks and is mathematically tractable. So we adopt the RBFN to approximate nonlinear robot dynamics. The RBFN generates control input signals based on the Lyapunov stability that is often used in the conventional control schemes. The saturation function is also chosen as an auxiliary controller to guarantee the stability and robustness of the control system under the external disturbances and modeling uncertainties.

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Direct adaptive control of chaotic nonlinear systems using a radial basis function network (방사 기저 함수 회로망을 이용한 혼돈 비선형 시스템의 직접 적응 제어)

  • 김근범;박광성;최윤호;박진배
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.219-222
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    • 1997
  • Due to the unpredictability and irregularity, the behaviors of chaotic systems are considered as undesirable phenomena to be avoided or controlled. Thus in this paper, to control systems showing chaotic behaviors, a direct adaptive control method using a radial basis function network (RBFN) as an excellent alternative of multi-layered feed-forward networks is presented. Compared with an indirect scheme, a direct one does not need the estimation of the controlled process and gives fast control effects. Through simulations on the two representative continuous-time chaotic systems, Duffing and Lorenz systems, validity of the proposed control scheme is shown.

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Signal Processing Techniques Based on Adaptive Radial Basis Function Networks for Chemical Sensor Arrays

  • Byun, Hyung-Gi
    • Journal of Sensor Science and Technology
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    • v.25 no.3
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    • pp.161-172
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    • 2016
  • The use of a chemical sensor array can help discriminate between chemicals when comparing one sample with another. The ability to classify pattern characteristics from relatively small pieces of information has led to growing interest in methods of sensor recognition. A variety of pattern recognition algorithms, including the adaptive radial basis function network (RBFN), may be applicable to gas and/ or odor classification. In this paper, we provide a broad review of approaches for various types of gas and/or odor identification techniques based on RBFN and drift compensation techniques caused by sensor poisoning and aging.

Backstepping Sliding Mode-based Model-free Control of Electro-hydraulic Systems

  • Truong, Hoai-Vu-Anh;Trinh, Hoai-An;Ahn, Kyoung-Kwan
    • Journal of Drive and Control
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    • v.19 no.1
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    • pp.51-61
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    • 2022
  • This paper presents a model-free system based on a framework of a backstepping sliding mode control (BSMC) with a radial basis function neural network (RBFNN) and adaptive mechanism for electro-hydraulic systems (EHSs). First, an EHS mathematical model was dedicatedly derived to understand the system behavior. Based on the system structure, BSMC was employed to satisfy the output performance. Due to the highly nonlinear characteristics and the presence of parametric uncertainties, a model-free approximator based on an RBFNN was developed to compensate for the EHS dynamics, thus addressing the difficulty in the requirement of system information. Adaptive laws based on the actor-critic neural network (ACNN) were implemented to suppress the existing error in the approximation and satisfy system qualification. The stability of the closed-loop system was theoretically proven by the Lyapunov function. To evaluate the effectiveness of the proposed algorithm, proportional-integrated-derivative (PID) and improved PID with ACNN (ACPID), which are considered two complete model-free methods, and adaptive backstepping sliding mode control, considered an ideal model-based method with the same adaptive laws, were used as two benchmark control strategies in a comparative simulation. The simulated results validated the superiority of the proposed algorithm in achieving nearly the same performance as the ideal adaptive BSMC.