• Title/Summary/Keyword: fuzzy-neural networks

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A Learning Fuzzy Logic Controller Using Neural Networks (신경회로망을 이용한 학습퍼지논리제어기)

  • Kim, B.S.;Ryu, K.B.;Min, S.S.;Lee, K.C.;Kim, C.E.;Cho, K.B.
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.225-230
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    • 1992
  • In this paper, a new learning fuzzy logic controller(LFLC) is presented. The proposed controller is composed of the main control part and the learning part. The main control part is a fuzzy logic controller(FLC) based on linguistic rules and fuzzy inference. For the learning part, artificial neural network(ANN) is added to FLC so that the controller may adapt to unknown plant and environment. According to the output values of the ANN part, which is learned using error back-propagation algorithm, scale factors of the FLC part are determined. These scale factors transfer the range of values of input variables into corresponding universe of discourse in the FLC part in order to achieve good performance. The effectiveness of the proposed control strategy has been demonstrated through simulations involving the control of an unknown robot manipulator with load disturbance.

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A Study on a neural-Net Based Call admission Control Using Fuzzy Pattern Estimator for ATM Networks (ATM망에서 퍼지 패턴 추정기를 이용한 신경망 호 수락제어에 관한 연구)

  • 이진이;이종찬;이종석
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.10a
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    • pp.173-179
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    • 1998
  • This paper proposes a new call admission control scheme utilizing an inverse fuzzy vector quantizer(IFVQ) and neural net, which combines benefits of IFVQ and flexibilities of FCM(Fuzzy-C-Menas) arithmatics, to decide whether a requested call that is not trained in learning phase to be connected or not. The system generates the estimated traffic pattern of the cell stream of a new call, using feasible/infeasible patterns in codebook, fuzzy membership values that represent the degree to which each pattern of codebook matches input pattern, and FCM arithmatics. The input to the NN is the vector consisted of traffic parameters which is the means and variances of the number of cells arriving inthe interval. After training(using error back propagation algorithm), when the NN is used for decision making, the decision as to whether to accept or reject a new call depends on whether the output is greater or less then decision threshold(+0.5). This method is a new technique for call admi sion control using the membership values as traffic parameter which declared to CAC at the call set up stage, and is valid for a very general traffic model in which the calls of a stream can belong to an unlimited number of traffic classes. Through the simmulation. it is founded the performance of the suggested method outforms compared to the conventional NN method.

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Neuro-Fuzzy Approach for Software Reliability Prediction (뉴로-퍼지 소프트웨어 신뢰성 예측)

  • Lee, Sang-Un
    • Journal of KIISE:Software and Applications
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    • v.27 no.4
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    • pp.393-401
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    • 2000
  • This paper explores neuro-fuzzy system in order to improve the software reliability predictability from failure data. We perform numerical simulations for actual 10 failure count and 4 failure time data sets from different software projects with the various number of rules. Comparative results for next-step prediction problem is presented to show the prediction ability of the neuro-fuzzy system. Experimental results show that neuro-fuzzy system is adapt well across different software projects. Also, performance of neuro-fuzzy system is favorably with the other well-known neural networks and statistical SRGMs.

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A Neuro Fuzzy Controller for DC-DC Converters

  • Huh, Sung-hoe;Hwang, Yong-Ha;Park, Gwi-Tae;Choy, Ick
    • Proceedings of the KIPE Conference
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    • 1998.10a
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    • pp.420-424
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    • 1998
  • A new type of controller for DC-DC converters is presented. The proposed neuro-fuzzy controller combines fuzzy logic with neural networks to adjust parameters of the fuzzy controller to the most appropriate. Neither the exact mathematical models of the DC-DC converters nor the tuning process of the parameters of the fuzzy controller are needed in the proposed scheme. Simulation results are presented to show the above process and transient, steady state responses, and load regulation of the given system.

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Efficiency Optimization Control of SynRM Drive with HAI Controller (HAI 제어기에 의한 SynRM의 효율 최적화 제어)

  • Choi, Jung-Sik;Ko, Jae-Sub;Lee, Jung-Ho;Kim, Jong-Kwan;Park, Byung-Sang;Park, Ki-Tae;Chung, Dong-Hwa
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.743-744
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    • 2006
  • This paper is proposed an efficiency optimization control algorithm for a synchronous reluctance motor which minimizes the copper and iron losses. The design of the speed controller based on adaptive fuzzy-neural networks(AFNN) controller that is implemented using fuzzy control and neural networks. The proposed algorithm allows the electromagnetic losses in variable speed and torque drives to be reduced while keeping good torque control dynamics. The control performance of the hybrid artificial intelligent(HAI) controller is evaluated by analysis for various operating conditions. Analysis results are presented to show the validity of the proposed algorithm

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Design of Self-Organizing Fuzzy Polynomial Neural Networks Architecture (자기구성 퍼지 다항식 뉴럴 네트워크 구조의 설계)

  • Park, Ho-Sung;Park, Keon-Jun;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2519-2521
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    • 2003
  • In this paper, we propose Self-Organizing Fuzzy Polynomial Neural Networks(SOFPNN) architecture for optimal model identification and discuss a comprehensive design methodology supporting its development. It is shown that this network exhibits a dynamic structure as the number of its layers as well as the number of nodes in each layer of the SOFPNN are not predetermined (as this is the case in a popular topology of a multilayer perceptron). As the form of the conclusion part of the rules, especially the regression polynomial uses several types of high-order polynomials such as linear, quadratic, and modified quadratic. As the premise part of the rules, both triangular and Gaussian-like membership function are studied and the number of the premise input variables used in the rules depends on that of the inputs of its node in each layer. We introduce two kinds of SOFPNN architectures, that is, the basic and modified one with both the generic and the advanced type. The superiority and effectiveness of the proposed SOFPNN architecture is demonstrated through nonlinear function numerical example.

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Efficiency Optimization Control of SynRM with Hybrid Artificial Intelligent Controller (하이브리드 인공지능 제어기에 의한 SynRM의 효율 최적화 제어)

  • Choi, Jung-Sik;Ko, Jae-Sub;Lee, Jung-Ho;Chung, Dong-Hwa
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2006.05a
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    • pp.321-326
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    • 2006
  • This paper is proposed an efficiency optimization control algorithm for a synchronous reluctance motor which minimizes the copper and iron losses. The design of the speed controller based on adaptive fuzzy-neural networks(AFNN) controller that is implemented using fuzzy control and neural networks. There exists a variety of combinations of d and q-axis current which provide a specific motor torque. The objective of the efficiency optimization controller is to seek a combination of d and q-axis current components, which provides minimum losses at a certain operating point in steady state. It is shown that the current components which directly govern the torque production have been very well regulated by the efficiency optimization control scheme. The proposed algorithm allows the electromagnetic losses in variable speed and torque drives to be reduced while keeping good torque control dynamics. The control performance of the hybrid artificial intelligent controller is evaluated by analysis for various operating conditions. Analysis results are presented to show the validity of the proposed algorithm.

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Forecasting Short-Term KOSPI using Wavelet Transforms and Fuzzy Neural Network (웨이블릿 변환과 퍼지 신경망을 이용한 단기 KOSPI 예측)

  • Shin, Dong-Kun;Chung, Kyung-Yong
    • The Journal of the Korea Contents Association
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    • v.11 no.6
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    • pp.1-7
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    • 2011
  • The methodology of KOSPI forecast has been considered as one of the most difficult problem to develop accurately since short-term KOSPI is correlated with various factors including politics and economics. In this paper, we presents a methodology for forecasting short-term trends of stock price for five days using the feature selection method based on a neural network with weighted fuzzy membership functions (NEWFM). The distributed non-overlap area measurement method selects the minimized number of input features by removing the worst input features one by one. A technical indicator are selected for preprocessing KOSPI data in the first step. In the second step, thirty-nine numbers of input features are produced by wavelet transforms. Twelve numbers of input features are selected as the minimized numbers of input features from thirty-nine numbers of input features using the non-overlap area distribution measurement method. The proposed method shows that sensitivity, specificity, and accuracy rates are 72.79%, 74.76%, and 73.84%, respectively.

Detecting Ventricular Tachycardia/Fibrillation Using Neural Network with Weighted Fuzzy Membership Functions and Wavelet Transforms (가중 퍼지소속함수 기반 신경망과 웨이블릿 변환을 이용한 심실 빈맥/세동 검출)

  • Shin, Dong-Kun;Zhang, Zhen-Xing;Lee, Sang-Hong;Lim, Joon-S.;Lee, Jung-Hyun
    • The Journal of the Korea Contents Association
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    • v.9 no.7
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    • pp.19-26
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    • 2009
  • This paper presents an approach to classify normal and ventricular tachycardia/fibrillation(VT/VF) from the Creighton University Ventricular Tachyarrhythmia Database(CUDB) using the neural network with weighted fuzzy membership functions(NEWFM) and wavelet transforms. In the first step, wavelet transforms are used to obtain the detail coefficients at levels 3 and 4. In the second step, all of detail coefficients d3 and d4 are classified into four intervals, respectively, and then the standard deviations of the specific intervals are used as eight numbers of input features of NEWFM. NEWFM classifies normal and VT/VF beats using eight numbers of input features, and then the accuracy rate is 90.1%.

Queue Detection using Fuzzy-Based Neural Network Model (퍼지기반 신경망모형을 이용한 대기행렬 검지)

  • KIM, Daehyon
    • Journal of Korean Society of Transportation
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    • v.21 no.2
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    • pp.63-70
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    • 2003
  • Real-time information on vehicle queue at intersections is essential for optimal traffic signal control, which is substantial part of Intelligent Transport Systems (ITS). Computer vision is also potentially an important element in the foundation of integrated traffic surveillance and control systems. The objective of this research is to propose a method for detecting an exact queue lengths at signalized intersections using image processing techniques and a neural network model Fuzzy ARTMAP, which is a supervised and self-organizing system and claimed to be more powerful than many expert systems, genetic algorithms. and other neural network models like Backpropagation, is used for recognizing different patterns that come from complicated real scenes of a car park. The experiments have been done with the traffic scene images at intersections and the results show that the method proposed in the paper could be efficient for the noise, shadow, partial occlusion and perspective problems which are inevitable in the real world images.