• Title/Summary/Keyword: Neural Networks model

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Design of an Adaptive Backstepping Speed Controller for Induction Motors with Uncertainties using Neural Networks (신경회로망을 이용한 불확실성을 갖는 유도전동기의 적응 백스테핑 속도제어기 설계)

  • Lee, Eun-Wook;Chung, Kee-Chull;Lee, Seung-Hak
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.11
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    • pp.476-482
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    • 2006
  • Based on a field-oriented model of induction motor, an adaptive backstepping control approach using neural networks is proposed in this paper for the speed control of induction motors with uncertainties at a minimum of information. Neural networks are used to approximate most of uncertainties which are derived from unknown motor parameters, load torque disturbances and unknown nonlinearities and an adaptive backstepping controller is used to derive adaptive law of neural networks and control input directly. The controller is implemented by the hardware using DSP and the effectiveness of the proposed approach is verified by carrying out the experiment.

Application of Artificial Neural Networks(ANN) to Ultrasonically Enhanced Soil Flushing of Contaminated Soils (초음파-토양수세법을 이용한 오염지반 복원률증대에 인공신경망의 적용)

  • 황명기;김지형;김영욱
    • Journal of the Korean Geotechnical Society
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    • v.19 no.6
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    • pp.343-350
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    • 2003
  • The range of applications of artificial neural networks(Am) in many branches of geotechnical engineering is growing rapidly. This study was undertaken to develop an analysis model representing ultrasonically enhanced soil flushing by the use of ANN. Input data for the model-development were obtained by laboratory study, and used for training and verification. Analyses involved various ranges of momentum, loaming rate, activation function, hidden layer, and nodes. Results of the analyses were used to obtain the optimum conditions for establishing and verifying the model. The coefficient of correlation between the measured and the predicted data using the developed model was relatively high. It shows potential application of ANN to ultrasonically enhanced soil flushing which is not easy to build up a mathematical model.

A Study on the Optimal Design of Polynomial Neural Networks Structure (다항식 뉴럴네트워크 구조의 최적 설계에 관한 연구)

  • O, Seong-Gwon;Kim, Dong-Won;Park, Byeong-Jun
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.3
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    • pp.145-156
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    • 2000
  • In this paper, we propose a new methodology which includes the optimal design procedure of Polynomial Neural Networks(PNN) structure for model identification of complex and nonlinear system. The proposed PNN algorithm is based on GMDA(Group Method of Data handling) method and its structure is similar to Neural Networks. But the structure of PNN is not fixed like in conventional Neural Networks and can be generated. The each node of PNN structure uses several types of high-order polynomial such as linear, quadratic and cubic, and is connected as various kinds of multi-variable inputs. In other words, the PNN uses high-order polynomial as extended type besides quadratic polynomial used in GMDH, and the number of input of its node in each layer depends on that of variables used in the polynomial. The design procedure to obtain an optimal model structure utilizing PNN algorithm is shown in each stage. The study is illustrated with the aid of pH neutralization process data besides representative time series data for gas furnace process used widely for performance comparison, and shows that the proposed PNN algorithm can produce the model with higher accuracy than previous other works. And performance index related to approximation and prediction capabilities of model is evaluated and also discussed.

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Dynamic Hand Gesture Recognition Using CNN Model and FMM Neural Networks (CNN 모델과 FMM 신경망을 이용한 동적 수신호 인식 기법)

  • Kim, Ho-Joon
    • Journal of Intelligence and Information Systems
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    • v.16 no.2
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    • pp.95-108
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    • 2010
  • In this paper, we present a hybrid neural network model for dynamic hand gesture recognition. The model consists of two modules, feature extraction module and pattern classification module. We first propose a modified CNN(convolutional Neural Network) a pattern recognition model for the feature extraction module. Then we introduce a weighted fuzzy min-max(WFMM) neural network for the pattern classification module. The data representation proposed in this research is a spatiotemporal template which is based on the motion information of the target object. To minimize the influence caused by the spatial and temporal variation of the feature points, we extend the receptive field of the CNN model to a three-dimensional structure. We discuss the learning capability of the WFMM neural networks in which the weight concept is added to represent the frequency factor in training pattern set. The model can overcome the performance degradation which may be caused by the hyperbox contraction process of conventional FMM neural networks. From the experimental results of human action recognition and dynamic hand gesture recognition for remote-control electric home appliances, the validity of the proposed models is discussed.

A New Design of Fuzzy Neural Networks Using Data Information (데이터 정보를 이용한 퍼지 뉴럴 네트워크의 새로운 설계)

  • Park, Keon-Jun;Oh, Sung-Kwun;Kim, Hyun-Ki
    • Proceedings of the KIEE Conference
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    • 2006.04a
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    • pp.273-275
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    • 2006
  • In this paper, we introduce a new design of fuzzy neural networks using input-output data information of target system. The proposed fuzzy neural networks is constructed by input-output data information and used the center of data distance by HCM clustering to obtain the characteristics of data. A membership function is defined by HCM clustering and is applied input-output dat included each rule to conclusion polynomial functions. We use triangular membership functions and simplified fuzzy inference, linear fuzzy inference, and modified quadratic fuzzy inference in conclusion. In the networks learning, back propagation algorithm of network is used to update the parameters of the network. The proposed model is evaluated with benchmark data.

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Identification of nonlinear dynamical systems based on self-organized distributed networks (자율분산 신경망을 이용한 비선형 동적 시스템 식별)

  • 최종수;김형석;김성중;권오신;김종만
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.4
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    • pp.574-581
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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 Networks(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 Self-Organized Distributed Networks (SODN). The learning with the SODN is fast and precise. Such properties are caused from the local learning mechanism. Each local network learns only data in a subregion. This paper also discusses neural network as identifier of nonlinear dynamical systems. The structure of nonlinear system identification employs series-parallel model. The identification procedure is based on a discrete-time formulation. Through extensive simulation, SODN is shown to be effective for identification of nonlinear dynamical systems. (author). 13 refs., 7 figs., 2 tabs.

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Fuzzy Relation-Based Fuzzy Neural-Networks Using a Hybrid Identification Algorithm

  • Park, Ho-Seung;Oh, Sung-Kwun
    • International Journal of Control, Automation, and Systems
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    • v.1 no.3
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    • pp.289-300
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    • 2003
  • In this paper, we introduce an identification method in Fuzzy Relation-based Fuzzy Neural Networks (FRFNN) through a hybrid identification algorithm. The proposed FRFNN modeling implement system structure and parameter identification in the efficient form of "If...., then... " statements, and exploit the theory of system optimization and fuzzy rules. The FRFNN modeling and identification environment realizes parameter identification through a synergistic usage of genetic optimization and complex search method. The hybrid identification algorithm is carried out by combining both genetic optimization and the improved complex method in order to guarantee both global optimization and local convergence. An aggregate objective function with a weighting factor is introduced to achieve a sound balance between approximation and generalization of the model. The proposed model is experimented with using two nonlinear data. The obtained experimental results reveal that the proposed networks exhibit high accuracy and generalization capabilities in comparison to other models.er models.

Neural Networks-Based Damage Detection for Bridges Considering Errors in Baseline Finite Element Models (모델링 오차를 고려한 신경망 기법 기반 손상추정방법)

  • Lee, Jong-Jae;Yun, Chung-Bang;Lee, Jong-Won;Jung, Hie-Young
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.04a
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    • pp.382-387
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    • 2003
  • In this paper, a neural networks-based damage detection method using the modal properties is presented, which can effectively reduce the effect of the modeling errors in the baseline finite element model from which the training patterns for the networks are to be generated. The differences or the ratios of the mode shape components between before and after damage are used as the input to the neural networks in this method, since they are found to be less sensitive to the modeling errors than the mode shapes themselves. Results of laboratory test on a simply supported bridge model and field test on a bridge with multiple girders confirm the applicability of the present method.

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Genetically Optimized Fuzzy Polynomial Neural Network and Its Application to Multi-variable Software Process

  • Lee In-Tae;Oh Sung-Kwun;Kim Hyun-Ki;Pedrycz Witold
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.6 no.1
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    • pp.33-38
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    • 2006
  • In this paper, we propose a new architecture of Fuzzy Polynomial Neural Networks(FPNN) by means of genetically optimized Fuzzy Polynomial Neuron(FPN) and discuss its comprehensive design methodology involving mechanisms of genetic optimization, especially Genetic Algorithms(GAs). The conventional FPNN developed so far are based on mechanisms of self-organization and evolutionary optimization. The design of the network exploits the extended Group Method of Data Handling(GMDH) with some essential parameters of the network being provided by the designer and kept fixed throughout the overall development process. This restriction may hamper a possibility of producing an optimal architecture of the model. The proposed FPNN gives rise to a structurally optimized network and comes with a substantial level of flexibility in comparison to the one we encounter in conventional FPNNs. It is shown that the proposed advanced genetic algorithms based Fuzzy Polynomial Neural Networks is more useful and effective than the existing models for nonlinear process. We experimented with Medical Imaging System(MIS) dataset to evaluate the performance of the proposed model.

Texture segmentation using Neural Networks and multi-scale Bayesian image segmentation technique (신경회로망과 다중스케일 Bayesian 영상 분할 기법을 이용한 결 분할)

  • Kim Tae-Hyung;Eom Il-Kyu;Kim Yoo-Shin
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.4 s.304
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    • pp.39-48
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    • 2005
  • This paper proposes novel texture segmentation method using Bayesian estimation method and neural networks. We use multi-scale wavelet coefficients and the context information of neighboring wavelets coefficients as the input of networks. The output of neural networks is modeled as a posterior probability. The context information is obtained by HMT(Hidden Markov Tree) model. This proposed segmentation method shows better performance than ML(Maximum Likelihood) segmentation using HMT model. And post-processed texture segmentation results as using multi-scale Bayesian image segmentation technique called HMTseg in each segmentation by HMT and the proposed method also show that the proposed method is superior to the method using HMT.