• Title/Summary/Keyword: electrical networks

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Classification of the Types of Defects in Steam Generator Tubes using the Quasi-Newton Method

  • Lee, Joon-Pyo;Jo, Nam-H.;Roh, Young-Su
    • Journal of Electrical Engineering and Technology
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    • 제5권4호
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    • pp.666-671
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    • 2010
  • Multi-layer perceptron neural networks have been constructed to classify four types of defects in steam generator tubes. Three features are extracted from the signals of the eddy current testing method. These include maximum impedance, phase angle at the point of maximum impedance, and an angle between the point of maximum impedance and the point of half the maximum impedance. Two hundred sets of these features are used for training and assessing the networks. Two approaches are involved to train the networks and to classify the defect type. One is the conjugate gradient method and the other is the Broydon-Fletcher-Goldfarb-Shanno method which is recognized as the most popular algorithm of quasi-Newton methods. It is found from the computation results that the training time of the Broydon-Fletcher-Goldfarb-Shanno method is much faster than that of the conjugate gradient method in most cases. On the other hand, no significant difference of the classification performance between the two methods is observed.

신경회로망을 이용한 Slotless PMLSM의 추력 최적화 (The optimum for thrust force of slotless type Permanent Magnet Linear Synchronous Motor using neural network)

  • 이동엽;문재윤;조성호;김규탁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.94-96
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    • 2002
  • This paper is deal with the method of redesign for optimum thrust model using Neural-Networks in Permanent Magnet Linear Synchrous Motor(PMLSM). This method is saved time compared with design method using only Finite Element Method(FEM). In this paper data sets for training Neural-Networks obtained using 2D FEM. To confirm the validity of the data sets for training Neural-Networks optimum values of that Is compared with results of FEM. And then. this method is verified that it could be applied to the design for Slotless type PMLSM.

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퍼지 신경망 제어기의 구조 및 매개 변수 최적화 (The Structure and Parameter Optimization of the Fuzzy-Neuro Controller)

  • 장욱;권오국;주영훈;윤태성;박진배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 B
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    • pp.739-742
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    • 1997
  • This paper proposes the structure and parameter optimization technique of fuzzy neural networks using genetic algorithm. Fuzzy neural network has advantages of both the fuzzy inference system and neural network. The determination of the optimal parameters and structure of the fuzzy neural networks, however, requires special efforts. To solve these problems, we propose a new learning method for optimization of fuzzy neural networks using genetic algorithm. It can optimize the structure and parameters of the entire fuzzy neural network globally. Numerical example is provided to show the advantages of the proposed method.

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THE EFFICIENCY ROUTING ALGORITHM FOR MULTIMEDIA TRANSMISSION IN DIGITAL HOME NETWORK SCENARIOS

  • Nguyen Thanh Tung;Ahn Sea-Young;An Sun-Shin
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2006년도 한국컴퓨터종합학술대회 논문집 Vol.33 No.1 (D)
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    • pp.136-138
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    • 2006
  • The high-rate Wireless Personal Area Networks (WPANs) which IEEE 802.15.3 standard support, foster the Digital Home Network (DHN) scenarios with high rate multimedia data transmission. Actually, there are a few routing protocols for ad-hoc networks which considered the terminal location information and routing metric to reduce the energy consumption and optimize the routing path in mobile system. Based on other routing protocols, this paper presents the reliable location-based routing algorithm which is an adaptation to these networks.

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A Novel Range-free Localization Algorithm for Anisotropic Networks

  • Lee, Jae-Hun;Chung, Woo-Yong;Kim, Eun-Tai
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제11권4호
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    • pp.223-228
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    • 2011
  • In this paper, a novel range-free localization algorithm for anisotropic networks is proposed. In the proposed method, the characteristics of the given network are considered and each sensor node estimates the relation between the hop counts and the geographical distances. Unlike most of the previous localization algorithms, the proposed method performs well not only in the isotropic network but also in the anisotropic networks. The proposed method is applied to both isotropic and anisotropic network topologies and the simulation results demonstrate that the method exhibits excellent and robust performances.

Evolvable Neural Networks for Time Series Prediction with Adaptive Learning Interval

  • Seo, Sang-Wook;Lee, Dong-Wook;Sim, Kwee-Bo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제8권1호
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    • pp.31-36
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    • 2008
  • This paper presents adaptive learning data of evolvable neural networks (ENNs) for time series prediction of nonlinear dynamic systems. ENNs are a special class of neural networks that adopt the concept of biological evolution as a mechanism of adaptation or learning. ENNs can adapt to an environment as well as changes in the enviromuent. ENNs used in this paper are L-system and DNA coding based ENNs. The ENNs adopt the evolution of simultaneous network architecture and weights using indirect encoding. In general just previous data are used for training the predictor that predicts future data. However the characteristics of data and appropriate size of learning data are usually unknown. Therefore we propose adaptive change of learning data size to predict the future data effectively. In order to verify the effectiveness of our scheme, we apply it to chaotic time series predictions of Mackey-Glass data.

Evolvable Neural Networks for Time Series Prediction with Adaptive Learning Interval

  • Lee, Dong-Wook;Kong, Seong-G;Sim, Kwee-Bo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.920-924
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    • 2005
  • This paper presents adaptive learning data of evolvable neural networks (ENNs) for time series prediction of nonlinear dynamic systems. ENNs are a special class of neural networks that adopt the concept of biological evolution as a mechanism of adaptation or learning. ENNs can adapt to an environment as well as changes in the environment. ENNs used in this paper are L-system and DNA coding based ENNs. The ENNs adopt the evolution of simultaneous network architecture and weights using indirect encoding. In general just previous data are used for training the predictor that predicts future data. However the characteristics of data and appropriate size of learning data are usually unknown. Therefore we propose adaptive change of learning data size to predict the future data effectively. In order to verify the effectiveness of our scheme, we apply it to chaotic time series predictions of Mackey-Glass data.

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다층 퍼지뉴럴 네트워크의 설계 (Design of Multi-layer Fuzzy Neural Networks)

  • Park, Byoung-Jun;Park, Keon-Jun;Oh, Sung-Kwun
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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    • pp.307-310
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    • 2004
  • In this study, a new architecture and comprehensive design methodology of genetically optimized Multi-layer Fuzzy Neural Networks (gMFNN) are introduced and a series of numeric experiments are carried out. The gMFNN architecture results from a synergistic usage of the hybrid system generated by combining Fuzzy Neural Networks (FNN) with Polynomial Neural Networks (PNN), FNN contributes to the formation of the premise part of the overall network structure of the gMFNN. The consequence part of the gMFNN is designed using PNN.

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Stacked Autoencoder를 이용한 특징 추출 기반 Fuzzy k-Nearest Neighbors 패턴 분류기 설계 (Design of Fuzzy k-Nearest Neighbors Classifiers based on Feature Extraction by using Stacked Autoencoder)

  • 노석범;오성권
    • 전기학회논문지
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    • 제64권1호
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    • pp.113-120
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    • 2015
  • In this paper, we propose a feature extraction method using the stacked autoencoders which consist of restricted Boltzmann machines. The stacked autoencoders is a sort of deep networks. Restricted Boltzmann machines (RBMs) are probabilistic graphical models that can be interpreted as stochastic neural networks. In terms of pattern classification problem, the feature extraction is a key issue. We use the stacked autoencoders networks to extract new features which have a good influence on the improvement of the classification performance. After feature extraction, fuzzy k-nearest neighbors algorithm is used for a classifier which classifies the new extracted data set. To evaluate the classification ability of the proposed pattern classifier, we make some experiments with several machine learning data sets.

비결함 샘플 데이타 제어를 가지는 정적 지연 뉴럴 네트웍의 강인 상태추정 (H State Estimation of Static Delayed Neural Networks with Non-fragile Sampled-data Control)

  • 유아연;이상문
    • 전기학회논문지
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    • 제66권1호
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    • pp.171-178
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    • 2017
  • This paper studies the state estimation problem for static neural networks with time-varying delay. Unlike other studies, the controller scheme, which involves time-varying sampling and uncertainties, is first employed to design the state estimator for delayed static neural networks. Based on Lyapunov functional approach and linear matrix inequality technique, the non-fragile sampled-data estimator is designed such that the resulting estimation error system is globally asymptotically stable with $H_{\infty}$ performance. Finally, the effectiveness of the developed results is demonstrated by a numerical example.