• Title/Summary/Keyword: Neural

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An Integrated Approach Using Change-Point Detection and Artificial neural Networks for Interest Rates Forecasting

  • Oh, Kyong-Joo;Ingoo Han
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2000.04a
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    • pp.235-241
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    • 2000
  • This article suggests integrated neural network models for the interest rate forecasting using change point detection. The basic concept of proposed model is to obtain intervals divided by change point, to identify them as change-point groups, and to involve them in interest rate forecasting. the proposed models consist of three stages. The first stage is to detect successive change points in interest rate dataset. The second stage is to forecast change-point group with data mining classifiers. The final stage is to forecast the desired output with BPN. Based on this structure, we propose three integrated neural network models in terms of data mining classifier: (1) multivariate discriminant analysis (MDA)-supported neural network model, (2) case based reasoning (CBR)-supported neural network model and (3) backpropagation neural networks (BPN)-supported neural network model. Subsequently, we compare these models with a neural networks (BPN)-supported neural network model. Subsequently, we compare these models with a neural network model alone and, in addition, determine which of three classifiers (MDA, CBR and BPN) can perform better. This article is then to examine the predictability of integrated neural network models for interest rate forecasting using change-point detection.

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Optimal structure of wavelet neural network systems using genetic algorithm (유전 알고리듬을 이용한 웨이블릿 신경회로망의 최적 구조 설계)

  • 이창민;서재용;전홍태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.05a
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    • pp.126-129
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    • 2000
  • In order to approximate a nonlinear function, wavelet neural networks combining wavelet theory and neural networks have been proposed as an alterantive to coventional multi-layered neural networks. Wavelet neural networks provide better approximating performance than conventional neural networks. In this paper, an effective method to construct an optimal wavelet neural network is proposed using genetic algorithm. This is verified through experimental results.

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STEPANOV ALMOST PERIODIC SOLUTIONS OF CLIFFORD-VALUED NEURAL NETWORKS

  • Lee, Hyun Mork
    • Journal of the Chungcheong Mathematical Society
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    • v.35 no.1
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    • pp.39-52
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    • 2022
  • We introduce Clifford-valued neural networks with leakage delays. Furthermore, we study the uniqueness and existence of Clifford-valued Hopfield artificial neural networks having the Stepanov weighted pseudo almost periodic forcing terms on leakage delay terms. However the noncommutativity of the Clifford numbers' multiplication made our investigation diffcult, so our results are obtained by decomposing Clifford-valued neural networks into real-valued neural networks. Our analysis is based on the differential inequality techniques and the Banach contraction mapping principle.

Nonlinear Controller Design by Hybrid Identification of Fuzzy-Neural Network and Neural Network (퍼지-신경회로망과 신경회로망의 혼합동정에 의한 비선형 제어기 설계)

  • 이용구;손동설;엄기환
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.11
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    • pp.127-139
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    • 1996
  • In this paper we propose a new controller design method using hybrid fuzzy-neural netowrk and neural network identification in order ot control systems which are more and more getting nonlinearity. Proposed method performs, for a nonlinear plant with unknown functions, hybird identification using a fuzzy-neural network and a neural network, and then a stable nonlinear controller is designed with those identified informations. To identify a nonlinear function, which is directly related to input signals, we can use a neural network which is satisfied with the proposed stable condition. To identify a nonlinear function, which is not directly related to input signals, we can use a fuzzy-neural network which has excellent identification characteristics. In order to verify excellent control performances of the proposed method, we compare the porposed control method with a conventional neural network control method through simulations and experiments with one link manipulator.

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Object Recognition Using Neuro-Fuzzy Inference System (뉴로-퍼지 추론 시스템을 이용한 물체인식)

  • 김형근;최갑석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.5
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    • pp.482-494
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    • 1992
  • In this paper, the neuro-fuzzy inferene system for the effective object recognition is studied. The proposed neuro-fuzzy inference system combines learning capability of neural network with inference process of fuzzy theory, and the system executes the fuzzy inference by neural network automatically. The proposed system consists of the antecedence neural network, the consequent neural network, and the fuzzy operational part, For dissolving the ambiguity of recognition due to input variance in the neuro-fuzzy inference system, the antecedence’s fuzzy proposition of the inference rules are automatically produced by error back propagation learining rule. Therefore, when the fuzzy inference is made, the shape of membership functions os adaptively modified according to the variation. The antecedence neural netwerk constructs a separated MNN(Model Classification Neural Network)and LNN(Line segment Classification Neural Networks)for dissolving the degradation of recognition rate. The antecedence neural network can overcome the limitation of boundary decisoion characteristics of nrural network due to the similarity of extracted features. The increased recognition rate is gained by the consequent neural network which is designed to learn inference rules for the effective system output.

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A Controlled Neural Networks of Nonlinear Modeling with Adaptive Construction in Various Conditions (다변 환경 적응형 비선형 모델링 제어 신경망)

  • Kim, Jong-Man;Sin, Dong-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.1234-1238
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    • 2004
  • A Controlled neural networks are proposed in order to measure nonlinear environments in adaptive and in realtime. The structure of it is similar to recurrent neural networks: a delayed output as the input and a delayed error between tile output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by backpropagation and each weights are updated by RLS(Recursive Least Square). Consequently, this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. This new neural networks is Error Estimated Neural Networks. We can estimate nonlinear models in realtime by the proposed networks and control nonlinear models. To show the performance of this one, we have various experiments. And this controller call prove effectively to be control in the environments of various systems.

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A QP Artificial Neural Network Inverse Kinematic Solution for Accurate Robot Path Control

  • Yildirim Sahin;Eski Ikbal
    • Journal of Mechanical Science and Technology
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    • v.20 no.7
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    • pp.917-928
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    • 2006
  • In recent decades, Artificial Neural Networks (ANNs) have become the focus of considerable attention in many disciplines, including robot control, where they can be used to solve nonlinear control problems. One of these ANNs applications is that of the inverse kinematic problem, which is important in robot path planning. In this paper, a neural network is employed to analyse of inverse kinematics of PUMA 560 type robot. The neural network is designed to find exact kinematics of the robot. The neural network is a feedforward neural network (FNN). The FNN is trained with different types of learning algorithm for designing exact inverse model of the robot. The Unimation PUMA 560 is a robot with six degrees of freedom and rotational joints. Inverse neural network model of the robot is trained with different learning algorithms for finding exact model of the robot. From the simulation results, the proposed neural network has superior performance for modelling complex robot's kinematics.

Performance Comparison of Guitar Chords Classification Systems Based on Artificial Neural Network (인공신경망 기반의 기타 코드 분류 시스템 성능 비교)

  • Park, Sun Bae;Yoo, Do-Sik
    • Journal of Korea Multimedia Society
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    • v.21 no.3
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    • pp.391-399
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    • 2018
  • In this paper, we construct and compare various guitar chord classification systems using perceptron neural network and convolutional neural network without pre-processing other than Fourier transform to identify the optimal chord classification system. Conventional guitar chord classification schemes use, for better feature extraction, computationally demanding pre-processing techniques such as stochastic analysis employing a hidden markov model or an acoustic data filtering and hence are burdensome for real-time chord classifications. For this reason, we construct various perceptron neural networks and convolutional neural networks that use only Fourier tranform for data pre-processing and compare them with dataset obtained by playing an electric guitar. According to our comparison, convolutional neural networks provide optimal performance considering both chord classification acurracy and fast processing time. In particular, convolutional neural networks exhibit robust performance even when only small fraction of low frequency components of the data are used.

Nonlinear Neural Networks for Vehicle Modeling Control Algorithm based on 7-Depth Sensor Measurements (7자유도 센서차량모델 제어를 위한 비선형신경망)

  • Kim, Jong-Man;Kim, Won-Sop;Sin, Dong-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.525-526
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    • 2008
  • For measuring nonlinear Vehicle Modeling based on 7-Depth Sensor, the neural networks are proposed m adaptive and in realtime. The structure of it is similar to recurrent neural networks; a delayed output as the input and a delayed error between the output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by backpropagation and each weights are updated by RLS(Recursive Least Square). Consequently, this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. This new neural networks is Error Estimated Neural Networks. We can estimate nonlinear models in realtime by the proposed networks and control nonlinear models.

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A Robust Nonlinear Control Using the Neural Network Model on System Uncertainty (시스템의 불확실성에 대한 신경망 모델을 통한 강인한 비선형 제어)

  • 이수영;정명진
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.5
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    • pp.838-847
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    • 1994
  • Although there is an analytical proof of modeling capability of the neural network, the convergency error in nonlinearity modeling is inevitable, since the steepest descent based practical larning algorithms do not guarantee the convergency of modeling error. Therefore, it is difficult to apply the neural network to control system in critical environments under an on-line learning scheme. Although the convergency of modeling error of a neural network is not guatranteed in the practical learning algorithms, the convergency, or boundedness of tracking error of the control system can be achieved if a proper feedback control law is combined with the neural network model to solve the problem of modeling error. In this paper, the neural network is introduced for compensating a system uncertainty to control a nonlinear dynamic system. And for suppressing inevitable modeling error of the neural network, an iterative neural network learning control algorithm is proposed as a virtual on-line realization of the Adaptive Variable Structure Controller. The efficiency of the proposed control scheme is verified from computer simulation on dynamics control of a 2 link robot manipulator.

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