• Title/Summary/Keyword: backpropagation algorithm

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A Study On Adaptive Correlator Receiver with Narrow-band Interferance in CDMA System (CDMA System에서 협대역 간섭제거 적응 상관기에 관한 연구)

  • Jeong Chan-Ju;Yang Hwa-Sup;Kim Yong-Shik;Oh Seung-Jae;Kim Jae-Gab
    • Management & Information Systems Review
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    • v.3
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    • pp.201-214
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    • 1999
  • Adaptive correlator receiver with neural network based on complex multilayer perceptron is persented for suppressing interference of narrow-band of direct spread spectrum communication systems. Recursive least square algorithm with backpropagation error is used for fast convergence and better performance in adaptive correlator scheme. According to signal noise and transmission power, computer simulation results show that bit error ratio of adaptive correlator using neural network improved that of adative transversal filter of direct sequence spread spectrum considering of jamming and narrow-band interference. Bit error ratio of adaptive correlator with neural network is reduced about 10-1 than that of adaptive transversal filter where interference versus signal ratio is 5dB.

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Airline In-flight Meal Demand Forecasting with Neural Networks and Time Series Models

  • Lee, Young-Chan
    • Proceedings of the Korea Association of Information Systems Conference
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    • 2000.11a
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    • pp.36-44
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    • 2000
  • The purpose of this study is to introduce a more efficient forecasting technique, which could help result the reduction of cost in removing the waste of airline in-flight meals. We will use a neural network approach known to many researchers as the “Outstanding Forecasting Technique”. We employed a multi-layer perceptron neural network using a backpropagation algorithm. We also suggested using other related information to improve the forecasting performances of neural networks. We divided the data into three sets, which are training data set, cross validation data set, and test data set. Time lag variables are still employed in our model according to the general view of time series forecasting. We measured the accuracy of our model by “Mean Square Error”(MSE). The suggested model proved most excellent in serving economy class in-flight meals. Forecasting the exact amount of meals needed for each airline could reduce the waste of meals and therefore, lead to the reduction of cost. Better yet, it could enhance the cost competition of each airline, keep the schedules on time, and lead to better service.

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Stochastic approximation to an optimal performance o fthe neural convolutional decoders (신경회로망 콘볼루션 복호기의 최적 성능에 대한 확률적 근사화)

  • 유철우;강창언;홍대식
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.4
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    • pp.27-36
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    • 1996
  • It is well known that the viterbi algorithm proposed as a mthod of decoding convolutional codes is in fact maximum likelihood (ML) and therefore optimal. But, because hardware complexity grows exponentially with the constraint length, there will be severe constraints on the implementation of the viterbi decoders. In this paper, the three-layered backpropagation neural networks are proposed as an alternative in order to get sufficiently useful performance and deal successfully with the problems of the viterbi decoder. This paper shows that the neural convolutional decoder (NCD) can make a decision in the point of ML in decoding and describes simulation results. The cause of the difference between stochastic results and simulation results is discussed, and then thefuture prospect of the NCD is described on the basis of the characteristic of the transfer function.

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The Implementation of the structure and algorithm of Fuzzy Self-organizing Neural Networks(FSONN) based on FNN (FNN에 기초한 Fuzzy Self-organizing Neural Network(FSONN)의 구조와 알고리즘의 구현)

  • 김동원;박병준;오성권
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.05a
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    • pp.114-117
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    • 2000
  • In this paper, Fuzzy Self-organizing Neural Networks(FSONN) based on Fuzzy Neural Networks(FNN) is proposed to overcome some problems, such as the conflict between ovefitting and good generation, and low reliability. The proposed FSONN consists of FNN and SONN. Here, FNN is used as the premise part of FSONN and SONN is the consequnt part of FSONN. The FUN plays the preceding role of FSONN. For the fuzzy reasoning and learning method in FNN, Simplified fuzzy reasoning and backpropagation learning rule are utilized. The number of layers and the number of nodes in each layers of SONN that is based on the GMDH method are not predetermined, unlike in the case of the popular multi layer perceptron structure and can be generated. Also the partial descriptions of nodes can use various forms such as linear, modified quadratic, cubic, high-order polynomial and so on. In this paper, the optimal design procedure of the proposed FSONN is shown in each step and performance index related to approximation and generalization capabilities of model is evaluated and also discussed.

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Realtime Face Recognition by Analysis of Feature Information (특징정보 분석을 통한 실시간 얼굴인식)

  • Chung, Jae-Mo;Bae, Hyun;Kim, Sung-Shin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.9
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    • pp.822-826
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    • 2001
  • The statistical analysis of the feature extraction and the neural networks are proposed to recognize a human face. In the preprocessing step, the normalized skin color map with Gaussian functions is employed to extract the region of face candidate. The feature information in the region of the face candidate is used to detect the face region. In the recognition step, as a tested, the 120 images of 10 persons are trained by the backpropagation algorithm. The images of each person are obtained from the various direction, pose, and facial expression. Input variables of the neural networks are the geometrical feature information and the feature information that comes from the eigenface spaces. The simulation results of 10 persons show that the proposed method yields high recognition rates.

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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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Design of Artificial Neural Networks for Fuzzy Control System (퍼지제어 시스템을 위한 인공신경망 설계)

  • Jang, Mun-Seok;Jang, Deok-Cheol
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.5
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    • pp.626-633
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    • 1995
  • It is vary hard to identify the fuzzy rules and tune the membership functions of the fuzzy inference in fuzzy systems modeling, We propose a fuzzy neural network model which can automatically identify the fuzzy rules and tune the membership functions of fuzzy inference simultaneously using artificial neural networks, and modify backpropagation algorithm for improving the convergence. The proposed method is verified by the simulation for a robot manipulator.

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The Control of A Inverted Pendulum Using Backpropagation (역전파 알고리즘을 이용한 도립 진자 제어)

  • Choi, Yong-Gil;Hong, Dae-Seung;Yim, Wha-Yeong
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2380-2382
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    • 2000
  • Fuzzy system which are based on membership functions and rules, can control nonlinear, uncertian, complex system well. However, Fuzzy controller has problems: It is difficult to design a stable for amateur. To update the then-part membership functions of the fuzzy controller can be designed using the error back-propagation algorithm to be minimized error. Then we could be optimized the system choosing a good performance index. The proposed fuzzy controller based on neural network is applied to control an inverted pendulum for demonstration of the robustness of proposed methodology.

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Application of artificial neural networks to the response prediction of geometrically nonlinear truss structures

  • Cheng, Jin;Cai, C.S.;Xiao, Ru-Cheng
    • Structural Engineering and Mechanics
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    • v.26 no.3
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    • pp.251-262
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    • 2007
  • This paper examines the application of artificial neural networks (ANN) to the response prediction of geometrically nonlinear truss structures. Two types of analysis (deterministic and probabilistic analyses) are considered. A three-layer feed-forward backpropagation network with three input nodes, five hidden layer nodes and two output nodes is firstly developed for the deterministic response analysis. Then a back propagation training algorithm with Bayesian regularization is used to train the network. The trained network is then successfully combined with a direct Monte Carlo Simulation (MCS) to perform a probabilistic response analysis of geometrically nonlinear truss structures. Finally, the proposed ANN is applied to predict the response of a geometrically nonlinear truss structure. It is found that the proposed ANN is very efficient and reasonable in predicting the response of geometrically nonlinear truss structures.

Design and Implementation of the Quality Performance Improvement for Process System Using Neural Network (가공시스템에서 신경회로망을 이용한 품질의 성능 개선에 관한 설계 및 구현)

  • 문희근;김영탁;김수정;김관형;탁한호;이상배
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2002.12a
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    • pp.179-182
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    • 2002
  • In this paper, this system makes use of the analog sensor and converts the feature of fish analog signal when sensor is operating with CPU(80C196KC). Then, After signal processing, this feature Is classified a special feature and a outline of fish by using the neural network, one of the artificial intelligence scheme. This neural network classifies fish pattern of very simple and short calculation. This has linear activation function and the error backpropagation is used as a learning algorithm. And the neural network is learned in off-line process. Because an adaptation period of neural network is too long time when random initial weights are used, off-line learning Is induced to decrease the Progress time We confirmed this method has better performance than somewhat outdated machines.