• Title/Summary/Keyword: Neural Mechanism

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Neural Net Based User Feedback Learning Mechanism for Distributed Information Retrieval (분산 정보 검색을 위한 신경망 기반 사용자 피드백 학습 메카니즘)

  • Choi, Yong S.
    • The Journal of Korean Association of Computer Education
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    • v.4 no.2
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    • pp.85-95
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    • 2001
  • Since documents on the Web are naturally partitioned into many document databases, the efficient information retrieval process requires identifying the document databases that are most likely to provide relevant documents to the query and then querying the identified document databases. We propose a neural net based user feedback learning mechanism for such an efficient information retrieval. Presented learning mechanism learns about underlying document databases using the relevance feedbacks obtained from user's retrieval experiences. For a given query, the learning mechanism, which is sufficiently trained, discovers the document databases associated with the relevant documents and retrieves those documents effectively.

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An Action Mechanism of Substance P on the Tracheal Smooth Muscle Contraction in Rabbits (토끼 기관의 평활근 수축에 미치는 substance P 의 작용기전)

  • 명창률
    • Journal of Chest Surgery
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    • v.27 no.1
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    • pp.9-14
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    • 1994
  • Substance P[SP] has been known to be a peptide which may be plays a role as a neurotransmitter in central nervous system as well as peripheral autonomic nervous system. It has been reported that SP was widely distributed in the nerve of the tracheal smooth muscle and induced the muscle contraction. However, definite action mechanism of SP in the tracheal smooth muscle was not clear, yet. Thus, present experiment was performed to elucidate an effect of substance P and an action mechanism on contraction of the smooth muscle in rabbits. In order to find a neural mechanism to the effect of SP on the tracheal smooth muscle contraction, atropine sulfate, tetrodotoxin, propranol and phentolamine were administered at 10 min before the addition of SP. Otherwise,to find effect of SP antagonists on the action of SP, [D-Pro2, D-Try7,9]SP, [D-Arg1, D-Pro2, D-Trp7,9, Leu11]SP and [D-Pro4, D-Trp7,9]SP were administered as a same fashion. These following results were obtained. 1] SP induced contraction of the tracheal smooth muscle under resting condition and the contraction was increased dose-dependently. 2] Cholinergic blocker[atropine], neural blocker[tetrodotoxin] and adrenergic blocker[propranol and phentolamine] didn`t have an effect on the contractile response. 3] Three SP antagonists inhibited the contractile response. 4] Isoproterenol relaxed the contraction induced by SP. The above results suggested that SP induced contraction of the tracheal smooth muscle directly act to the smooth muscle in rabbits. The autonomic nervous system did not seem to participate in the SP action.

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Super-Resolution Using NLSA Mechanism (비지역 희소 어텐션 메커니즘을 활용한 초해상화)

  • Kim, Sowon;Park, Hanhoon
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.1
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    • pp.8-14
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    • 2022
  • With the development of deep learning, super-resolution (SR) methods have tried to use deep learning mechanism, instead of using simple interpolation. SR methods using deep learning is generally based on convolutional neural networks (CNN), but recently, SR researches using attention mechanism have been actively conducted. In this paper, we propose an approach of improving SR performance using one of the attention mechanisms, non-local sparse attention (NLSA). Through experiments, we confirmed that the performance of the existing SR models, IMDN, CARN, and OISR-LF-s can be improved by using NLSA.

Adaptive FNN Controller for High Performance Control of Induction Motor Drive (유도전동기 드라이브의 고성능 제어를 위한 적응 FNN 제어기)

  • 이정철;이홍균;정동화
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.9
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    • pp.569-575
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    • 2004
  • This paper is proposed adaptive fuzzy-neural network(FNN) controller for high performance of induction motor drive. The design of this algorithm based on FNN controller that is implemented using fuzzy control and neural network. This controller uses fuzzy rule as training patterns of a neural network. Also, this controller uses the back-propagation method to adjust the weights between the neurons of neural network in order to minimize the error between the command output and actual output. A model reference adaptive scheme is proposed in which the adaptation mechanism is executed by fuzzy logic based on the error and change of error measured between the motor speed and output of a reference model. The control Performance of the adaptive FNN controller is evaluated by analysis for various operating conditions. The results of analysis prove that the proposed control system has strong high performance and robustness to parameter variation. and steady- state accuracy and transient response.

High Performance of Induction Motor Drive with HAl Controller (HAI 제어기에 의한 유도전동기 드라이브의 고성능 제어)

  • Nam, Su-Myeong;Choi, Jung-Sik;Ko, Jae-Sub;Chung, Dong-Hwa
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.570-572
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    • 2005
  • This paper is proposed adaptive hybrid artificial intelligent(HAI) controller for high performance of induction motor drive. The design of this algorithm based on fuzzy-neural network(FNN) controller that is implemented using fuzzy control and neural network. This controller uses fuzzy rule as training patterns of a neural network. Also, this controller uses the back-propagation method to adjust the weights between the neurons of neural network in order to minimize the error between the command output and actual output. A model reference adaptive scheme is proposed in which the adaptation mechanism is executed by fuzzy logic based on the error and change of error measured between the motor speed and output of a reference model. The control performance of the adaptive FNN controller is evaluated by analysis for various operating conditions. The results of experiment prove that the proposed control system has strong high performance and robustness to parameter variation, and steady-state accuracy and transient response.

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Electrical Engineering Design Method Based on Neural Network and Application of Automatic Control System

  • Zhe, Zhang;Yongchang, Zhang
    • Journal of Information Processing Systems
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    • v.18 no.6
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    • pp.755-762
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    • 2022
  • The existing electrical engineering design method and the dynamic objective function in the application process of automatic control system fail to meet the unbounded condition, which affects the control tracking accuracy. In order to improve the tracking control accuracy, this paper studies the electrical engineering design method based on neural network and the application of automatic control system. This paper analyzes the structure and working mechanism of electrical engineering automation control system by an automation control model with main control objectives. Following the analysis, an optimal solution of controllability design and fault-tolerant control is figured out. The automatic control power coefficient is distributed based on an ideal control effect of system. According to the distribution results, an automatic control algorithm is based on neural network for accurate control. The experimental results show that the electrical automation control method based on neural network can significantly reduce the control following error to 3.62%, improve the accuracy of the electrical automation tracking control, thus meeting the actual production needs of electrical engineering automation control system.

Structure optimization of neural network using co-evolution (공진화를 이용한 신경회로망의 구조 최적화)

  • 전효병;김대준;심귀보
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.4
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    • pp.67-75
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    • 1998
  • In general, Evoluationary Algorithm(EAs) are refered to as methods of population-based optimization. And EAs are considered as very efficient methods of optimal sytem design because they can provice much opportunity for obtaining the global optimal solution. This paper presents a co-evolution scheme of artifical neural networks, which has two different, still cooperatively working, populations, called as a host popuation and a parasite population, respectively. Using the conventional generatic algorithm the host population is evolved in the given environment, and the parastie population composed of schemata is evolved to find useful schema for the host population. the structure of artificial neural network is a diagonal recurrent neural netork which has self-feedback loops only in its hidden nodes. To find optimal neural networks we should take into account the structure of the neural network as well as the adaptive parameters, weight of neurons. So we use the genetic algorithm that searches the structure of the neural network by the co-evolution mechanism, and for the weights learning we adopted the evolutionary stategies. As a results of co-evolution we will find the optimal structure of the neural network in a short time with a small population. The validity and effectiveness of the proposed method are inspected by applying it to the stabilization and position control of the invered-pendulum system. And we will show that the result of co-evolution is better than that of the conventioal genetic algorithm.

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The Modeling of Chaotic Nonlinear System Using Wavelet Based Fuzzy Neural Network

  • Oh, Joon-Seop;You, Sung-Jin;Park, Jin-Bae;Choi, Yoon-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.635-639
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    • 2004
  • In this paper, we present a novel approach for the structure of Fuzzy Neural Network(FNN) based on wavelet function and apply this network structure to the modeling of chaotic nonlinear systems. Generally, the wavelet fuzzy model(WFM) has the advantage of the wavelet transform by constituting the fuzzy basis function(FBF) and the conclusion part to equalize the linear combination of FBF with the linear combination of wavelet functions. However, it is very difficult to identify the fuzzy rules and to tune the membership functions of the fuzzy reasoning mechanism. Neural networks, on the other hand, utilize their learning capability for automatic identification and tuning. Therefore, we design a wavelet based FNN structure(WFNN) that merges these advantages of neural network, fuzzy model and wavelet transform. The basic idea of our wavelet based FNN is to realize the process of fuzzy reasoning of wavelet fuzzy system by the structure of a neural network and to make the parameters of fuzzy reasoning be expressed by the connection weights of a neural network. And our network can automatically identify the fuzzy rules by modifying the connection weights of the networks via the gradient descent scheme. To verify the efficiency of our network structure, we evaluate the modeling performance for chaotic nonlinear systems and compare it with those of the FNN and the WFM.

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Path Tracking Control Using a Wavelet Based Fuzzy Neural Network for Mobile Robots

  • Oh, Joon-Seop;Park, Yoon-Ho
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.4 no.1
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    • pp.111-118
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    • 2004
  • In this paper, we present a novel approach for the structure of Fuzzy Neural Network(FNN) based on wavelet function and apply this network structure to the solution of the tracking problem for mobile robots. Generally, the wavelet fuzzy model(WFM) has the advantage of the wavelet transform by constituting the fuzzy basis function(FBF) and the conclusion part to equalize the linear combination of FBF with the linear combination of wavelet functions. However, it is very difficult to identify the fuzzy rules and to tune the membership functions of the fuzzy reasoning mechanism. Neural networks, on the other hand, utilize their learning capability for automatic identification and tuning. Therefore, we design a wavelet based FNN structure(WFNN) that merges these advantages of neural network, fuzzy model and wavelet transform. The basic idea of our wavelet based FNN is to realize the process of fuzzy reasoning of wavelet fuzzy system by the structure of a neural network and to make the parameters of fuzzy reasoning be expressed by the connection weights of a neural network. And our network can automatically identify the fuzzy rules by modifying the connection weights of the networks via the gradient descent scheme. To verify the efficiency of our network structure, we evaluate the tracking performance for mobile robot and compare it with those of the FNN and the WFM.