• Title/Summary/Keyword: neural network.

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Adaptive Nonlinearity Compensation in Laser Interferometer using Neural Network (신경망 회로를 이용한 레이저 간섭계의 적응형 오차보정)

  • Heo, Gun-Hang;Lee, Woo-Ram;You, Kwan-Ho
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.86-88
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    • 2007
  • In the semiconductor manufacturing industry, the heterodyne laser interferometer plays as an ultra-precise measurement system. However, the heterodyne laser interferometer has some unwanted nonlinearity error which is caused from frequency-mixing. This is an obstacle to improve the measurement accuracy in nanometer scale. In this paper we propose a compensation algorithm based on RLS(recursive least square) method and artificial intelligence method, which reduce the nonlinearity error in the heterodyne laser interferometer. With the capacitance displacement sensor we get a reference signal which can be transformed into the intensity domain. Using the back-propagation Neural Network method, we train the network to track the reference signal. Through some experiments, we demonstrate the effectiveness of the proposed algorithm in measurement accuracy.

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Adaptive Control Method using Wavelet Neural Network (웨이브렛 신경회로망을 이용한 적응 제어 방식)

  • 정경권;손동설;이현관;이용구;엄기환
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.456-459
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    • 2001
  • In this paper, a wavelet neural network for adaptive control was proposed. The structure of this network is similar to that of the multilayer perceptron(MLP), except that here the sigmoid functions are replated by mother wavelet function in the hidden units. The simulation result showed the effectiveness of using the wavelet neural network structure in the adaptive control of one-link manipulator.

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A Study onthe Modelling and control Using GMDH Algorithm (GMDH 알고리즘을 이용한 모델링 및 제어에 관한 연구)

  • 최종헌;홍연찬
    • Journal of the Korean Institute of Intelligent Systems
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    • v.7 no.3
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    • pp.65-71
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    • 1997
  • With the emergence of neural network, there is a revived interest in identification of nonlinear systems. So in this paper, to identify unknown nonlinear systems dynamically we propose DPNN(Dynamic Polynomial Neural Network) using GMDH (Group Method of Data Handling) algorithm. The dynamic system identification using GMDH consists of applying a set of inputloutput data to train the network by dynamically computing the necessary coeffici1:nt sets. Then, MRAC(Mode1 Reference Adaptive Control) is designed to control nonlinear systems using DPNN. In the result, we can see that the modelling and control using DPNN work well by computer simulation.

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A Study on Driving Control using Neural Network Identifier (신경회로망 동정기를 이용한 AGV의 주행제어에 관한 연구)

  • 이영진;이진우;손주한;최성욱;김한근;조현철;이권순
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.151-151
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    • 2000
  • The objective of this paper is to develop the new robust and adaptive control system against external environments as applying the probabilistic recognition which is one of the inherent properties of immune system, ability of learning and memorization, and regulation theory of immune network to the system under engineering point of view. In this paper, HIA(Humoral Immune Algorithm) PID controller using Neural Network Identifier was proposed to drive the autonomous guided vehicle(AGV) more effectively. To verify the performance of the proposed HIA PID controller, some experiments for the control of steering and speed of that AGV are performed.

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Multiple fault diagnosis method by using HANN (계층신경망을 이용한 다중고장진단 기법)

  • 이석희;배용환;배태용;최홍태
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.790-795
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    • 1994
  • This paper describes multiple fault diagnosis method in complex system with hierarchical structure. Complex system is divided into subsystem, item, component. For diagnosing this hierarchical complex system, it is necessary to implement special neural network. We introducd to Hierarchical Artificial Neural Network(HANN) for this purpose. HANN consists of four level neural network, first level for symptom classification, second level for item fault diagnosis, third level for component symptom classification,forth level for component fault diagnosis. Each network is multi layer perceptron with 7 inputs, 30 hidden node and 7 outputs trainined by backpropagation. UNIX IPC(Inter Process Communication) is used for implementing HANN with multitasking and message transfer between processes in SUN workstation. We tested HANN in reactor system.

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The study on the Algorithm for Desing of Fuzzy Logic Controller Using Neural Network (신경회로망을 이용한 퍼지제어기 설계 알고리즘에 관한 연구)

  • 채명기;이상배
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.243-248
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    • 1996
  • In this paper, a general neural-network-based connectionist model, called Fuzzy Neural Network(FNN), is proposed for the realization of a fuzzy logic control system. The proposed FNN is a feedforward multi-layered network which integrates the basic elements and functions of a traditional fuzzy logic controller into a connectionist structure which has distributed learning abilities. Such FNN can be constructed from training examples by learning rule, and the connectionist structure can be trained to develop fuzzy logic rules and find optimal input/output membership functions. Computer simulation examples will be presented to illustrate the performance and applicability of the proposed FNN, and their associated learning algorithms.

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MODELLING THE DYNAMICS OF THE LEAD BISMUTH EUTECTIC EXPERIMENTAL ACCELERATOR DRIVEN SYSTEM BY AN INFINITE IMPULSE RESPONSE LOCALLY RECURRENT NEURAL NETWORK

  • Zio, Enrico;Pedroni, Nicola;Broggi, Matteo;Golea, Lucia Roxana
    • Nuclear Engineering and Technology
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    • v.41 no.10
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    • pp.1293-1306
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    • 2009
  • In this paper, an infinite impulse response locally recurrent neural network (IIR-LRNN) is employed for modelling the dynamics of the Lead Bismuth Eutectic eXperimental Accelerator Driven System (LBE-XADS). The network is trained by recursive back-propagation (RBP) and its ability in estimating transients is tested under various conditions. The results demonstrate the robustness of the locally recurrent scheme in the reconstruction of complex nonlinear dynamic relationships.

A Study on Optimal Layout of Two-Dimensional Rectangular Shapes Using Neural Network (신경회로망을 이용한 직사각형의 최적배치에 관한 연구)

  • 한국찬;나석주
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.12
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    • pp.3063-3072
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    • 1993
  • The layout is an important and difficult problem in industrial applications like sheet metal manufacturing, garment making, circuit layout, plant layout, and land development. The module layout problem is known to be non-deterministic polynomial time complete(NP-complete). To efficiently find an optimal layout from a large number of candidate layout configuration a heuristic algorithm could be used. In recent years, a number of researchers have investigated the combinatorial optimization problems by using neural network principles such as traveling salesman problem, placement and routing in circuit design. This paper describes the application of Self-organizing Feature Maps(SOM) of the Kohonen network and Simulated Annealing Algorithm(SAA) to the layout problem of the two-dimensional rectangular shapes.

A Neural Network Model to Recognize the Pattern of Intra-City Vehicle Travel Speeds for Truck Dispatching System (배차계획시스템을 위한 도시내 차량이동속도 패턴인식 신경망 모델)

  • 홍성철;박양병
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.50
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    • pp.221-230
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    • 1999
  • The important issue for intra-city truck dispatching system is to measure and store actual travel speeds between customer locations. Travel speeds(and times) in nearly all metropolitan areas change drastically during the day because of congestion in certain parts of the city road network. We propose a back-propagation neural network model to recognize the pattern of intra-city vehicle travel speeds between locations that relieve much burden for the data collection and computer storage requirements. On a real-world study using the travel speed data[1] collected in Seoul, we evaluate performance of neural network model and compare with Park & Song model[2] that employs the least square method.

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Implementation of A Pulse-mode Digital Neural Network with On-chip Learning Using Stochastic Computation (On-Chip 학습기능을 가진 확률연산 펄스형 디지털 신경망의 구현)

  • Wee, Jae-Woo;Lee, Chong-Ho
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2296-2298
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    • 1998
  • In this paper, an on-chip learning pulse-mode digital neural network with a massively parallel yet compact and flexible network architecture is suggested. Algebraic neural operations are replaced by stochastic processes using pseudo-random sequences and simple logic gates are used as basic computing elements. Using Back-propagation algorithm both feed-forward and learning phases are efficiently implemented with simple logical gates. RNG architecture using LFSR and barrel shifter are adopted to avoid some correlation between pulse trains. Suggested network is designed in digital circuit and its performance is verified by computer simulation.

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