• Title/Summary/Keyword: Network Function

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Initial Optimization of the RBFN with Time-Frequency Localization Using Genetic Algorithm (유전 알고리즘과 시간-주파수 지역화를 이용한 방사 기준 함수망의 초기 최적화)

  • 김성주;서재용;김용택;조현찬;전홍태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.221-224
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    • 2001
  • In this paper, we propose the initial optimized structure of the Radial Basis Function Network which is more simple in the part on the structure and converges more faster than Neural Network with the analysis method using Time-Frequency Localization and genetic algorithm. When we construct the hidden node with the Radial Basis Function whose localization is similar with an approximation target function in the plane of the Time and Frequency, we have initial structure of RBFN, After that, we evaluate the parameters of RBF in the network and the parameters needed for the network is more a few. Finally, we make a good decision of the initial structure having an ability of approximation.

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A learning control of DC servomotor using neural network

  • Kawabata, Hiroaki;Yamada, Katsuhisa;Zhong, Zhang;Takeda, Yoji
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.703-707
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    • 1994
  • This paper proposes a method of learning control in DC servomotor using a neural network. First we estimate the pulse transfer function of the servo system with an unknown load, then we determine the best gains of I-PD control system using a neural network. Each time the load changes, its best gains of the I-PD control system is computed by the neural network. And the best gains and its pulse transfer function for the case are stored in the memory. According the increase of the set of gains and its pulse transfer function, the learning control system can afford the most suitable I-PD gains instantly.

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Design of nonlinear system controller based on radial basis function network (Radial Basis 함수 회로망을 이용한 비선형 시스템 제어기의 설계에 관한 연구)

  • 박경훈;이양우;차득근
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1165-1168
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    • 1996
  • The neural network approach has been shown to be a general scheme for nonlinear dynamical system identification. Unfortunately the error surface of a Multilayer Neural Network(MNN) that widely used is often highly complex. This is a disadvantage and potential traps may exist in the identification procedure. The objective of this paper is to identify a nonlinear dynamical systems based on Radial Basis Function Networks(RBFN). The learning with RBFN is fast and precise. This paper discusses RBFN as identification procedure is based on a nonlinear dynamical systems. and A design method of model follow control system based on RBFN controller is developed. As a result of applying this method to inverted pendulum, the simulation has shown that RBFN can be used as identification and control of nonlinear dynamical systems effectively.

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Estimation of Equivalent Circuit Parameters of Underwater Acoustic Piezoelectric Transducer for Matching Network Design of Sonar Transmitter (소나 송신기의 정합회로 설계를 위한 수중 음향 압전 트랜스듀서의 등가회로 파라미터 추정)

  • Lee, Jeong-Min;Lee, Byung-Hwa;Baek, Kwang-Ryul
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.3
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    • pp.282-289
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    • 2009
  • This paper presents an estimation technique of the equivalent circuit parameters for an underwater acoustic piezoelectric transducer from the measured impedance. Estimated equivalent circuit can be used for the design of the impedance matching network of the sonar transmitter. A fitness function is proposed to minimize the error between the calculated impedance of the equivalent circuit and the measured impedance of the transducer. The equivalent circuit parameters are estimated by using the fitness function and the PSO(Particle Swarm Optimization) algorithm. The effectiveness of the proposed method is verified by the applications to a sandwich-type transducer and a dummy load. In addition, the impedance matching network is also designed by using the estimated equivalent circuit model.

Automatic optimization of WiBro network by using measured DM data (DM 데이터를 이용한 WiBro 무선망 자동최적화)

  • Jin, Hyuk-Soo;Jung, Hyun-Meen;Lee, Seong-Choon
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.335-336
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    • 2008
  • By using DM(Diagnostic Monitoring) data measured at WiBro network, automatic optimization function of WiBro network is implemented in this paper. The optimization function mentioned is able to be run on PC with 2GHz CPU and 1 GB memory. Automatic optimization function is one module of CellTREK that is a wireless network planning and optimization software developed by Infra Lab., KT.

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Implementation of Face Recognition System Using Neural Network

  • gi, Jung-Hun;yong, Kuc-Tae
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.169.2-169
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    • 2001
  • In this paper, we propose the face recognition system using the neural network. A difficult procedure in constructing the entire recognition systems is the feature extraction from the face imga. And a key poing is the design of the matching function that relates the set of feature values to the appropriate face candidates. We use the length and angle values as feature values that are extracted from the face image normalized to the range of [0,1]. These features values are applied to the input layer of the neural network. Then, these multi-layered perceptron learns or gives otput result. By using the neural network we need not to design the matching function. This function may have nonlinear attributes considerably and would be ...

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Development of a Neural-Fuzzy Control Algorithm for Dynamic Control of a Track Vehicle (궤도차량의 동적 제어를 위한 퍼지-뉴런 제어 알고리즘 개발)

  • 서운학
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.142-147
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    • 1999
  • This paper presents a new approach to the dynamic control technique for track vehicle system using neural network-fuzzy control method. The proposed control scheme uses a Gaussian function as a unit function in the neural network-fuzzy, and back propagation algorithm to train the fuzzy-neural network controller in the framework of the specialized learning architecture. It is proposed a learning controller consisting of two neural network-fuzzy based on independent reasoning and a connection net with fixed weights to simply the neural networks-fuzzy. The performance of the proposed controller is shown by simulation for trajectory tracking of the speed and azimuth of a track vehicle.

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Learning of Fuzzy Membership Function by Novel Fuzzy-Neural Networks (새로운 퍼지-신경망을 이용한 퍼지소속함수의 학습)

  • 추연규;탁한호
    • Journal of the Korean Institute of Navigation
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    • v.22 no.2
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    • pp.47-52
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    • 1998
  • Recently , there have been considerable researches about the fusion of fuzzy logic and neural networks. The propose of thise researches is to combine the advantages of both. After the function of approximation using GMDP (Generalized Multi-Denderite Product)neural network for defuzzification operation of fuzzy controller, a new fuzzy-neural network is proposed. Fuzzy membership function of the proposed fuzzy-neural network can be adjusted by learning in order to be adaptive to the variations of a parameter or the external environment. To show the applicability of the proposed fuzzy-nerual network, the proposed model is applied to a speed control o fDC sevo motor. By the hardware implementation, we obtained the desriable results.

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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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Nano-Resolution Connectomics Using Large-Volume Electron Microscopy

  • Kim, Gyu Hyun;Gim, Ja Won;Lee, Kea Joo
    • Applied Microscopy
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    • v.46 no.4
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    • pp.171-175
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    • 2016
  • A distinctive neuronal network in the brain is believed to make us unique individuals. Electron microscopy is a valuable tool for examining ultrastructural characteristics of neurons, synapses, and subcellular organelles. A recent technological breakthrough in volume electron microscopy allows large-scale circuit reconstruction of the nervous system with unprecedented detail. Serial-section electron microscopy-previously the domain of specialists-became automated with the advent of innovative systems such as the focused ion beam and serial block-face scanning electron microscopes and the automated tape-collecting ultramicrotome. Further advances in microscopic design and instrumentation are also available, which allow the reconstruction of unprecedentedly large volumes of brain tissue at high speed. The recent introduction of correlative light and electron microscopy will help to identify specific neural circuits associated with behavioral characteristics and revolutionize our understanding of how the brain works.