• Title/Summary/Keyword: Fuzzy LMS algorithm

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A Constructive Algorithm of Fuzzy Model for Nonlinear System Modeling (비선형 시스템 모델링을 위한 퍼지 모델 구성 알고리즘)

  • Choi, Jong-Soo
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.648-650
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    • 1998
  • This paper proposes a constructive algorithm for generating the Takagi-Sugeno type fuzzy model through the sequential learning from training data set. The proposed algorithm has a two-stage learning scheme that performs both structure and parameter learning simultaneously. The structure learning constructs fuzzy model using two growth criteria to assign new fuzzy rules for given observation data. The parameter learning adjusts the parameters of existing fuzzy rules using the LMS rule. To evaluate the performance of the proposed fuzzy modeling approach, well-known benchmark is used in simulation and compares it with other modeling approaches.

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Application of Sliding Mode fuzzy Control with Disturbance Prediction (외란 예측기가 포함된 슬라이딩 모드 퍼지 제어기의 응용)

  • 김상범;윤정방;구자인
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.04b
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    • pp.365-370
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    • 2000
  • A sliding mode fuzzy control (SMFC) algorithm is applied to design a controller for a benchmark problem on a wind- excited building. The structure is a 76-story concrete office tower with a height of 306 meters, hence the wind resistance characteristics are very important for the serviceability as well as the safety. A control system with an active tuned mass damper is assumed to be installed on the top floor. Since the structural acceleration is measured only at ,limited number of locations without measurement of the wind force, the structure of the conventional continuous sliding mode control may have the feed-back loop only. So, an adaptive least mean squares (LMS) filter is employed in the SMFC algorithm to generate a fictitious feed-forward loop. The adaptive LMS filter is designed based on the information of the stochastic characteristics of the wind velocity along the structure. A numerical study is carried out. and the performance of the present SMFC with the ,adaptive LMS filter is investigated in comparison with those of' other control, of algorithms such as linear quadratic Gaussian control, frequency domain optimal control, quadratic stability control, continuous sliding mode control, and H/sub ∞///sub μ/, control, which were reported by other researchers. The effectiveness of the adaptive LMS filter is also examined. The results indicate that the present algorithm is very efficient .

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Intelligent Adaptive Active Noise Control in Non-stationary Noise Environments (비정상 잡음환경에서의 지능형 적응 능동소음제어)

  • Mu, Xiangbin;Ko, JinSeok;Rheem, JaeYeol
    • The Journal of the Acoustical Society of Korea
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    • v.32 no.5
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    • pp.408-414
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    • 2013
  • The famous filtered-x least mean square (FxLMS) algorithm for active noise control (ANC) systems may become unstable in non-stationary noise environment. To solve this problem, Sun's algorithm and Akhtar's algorithm are developed based on modifying the reference signal in update of FxLMS algorithm, but these two algorithms have dissatisfactory stability in dealing with sustaining impulsive noise. In proposed algorithm, probability estimation and zero-crossing rate (ZCR) control are used to improve the stability and performance, at the same time, an optimal parameter selection based on fuzzy system is utilized. Computer simulation results prove the proposed algorithm has faster convergence and better stability in non-stationary noise environment.

Complex Fuzzy Logic Filter and Learning Algorithm

  • Lee, Ki-Yong;Lee, Joo-Hum
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.1E
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    • pp.36-43
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    • 1998
  • A fuzzy logic filter is constructed from a set of fuzzy IF-THEN rules which change adaptively to minimize some criterion function as new information becomes available. This paper generalizes the fuzzy logic filter and it's adaptive filtering algorithm to include complex parameters and complex signals. Using the complex Stone-Weierstrass theorem, we prove that linear combinations of the fuzzy basis functions are capable of uniformly approximating and complex continuous function on a compact set to arbitrary accuracy. Based on the fuzzy basis function representations, a complex orthogonal least-squares (COLS) learning algorithm is developed for designing fuzzy systems based on given input-output pairs. Also, we propose an adaptive algorithm based on LMS which adjust simultaneously filter parameters and the parameter of the membership function which characterize the fuzzy concepts in the IF-THEN rules. The modeling of a nonlinear communications channel based on a complex fuzzy is used to demonstrate the effectiveness of these algorithm.

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Modular Fuzzy Inference Systems for Nonlinear System Control (비선형 시스템 제어를 위한 모듈화 피지추론 시스템)

  • 권오신
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.5
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    • pp.395-399
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    • 2001
  • This paper describes modular fuzzy inference systems(MFIS) with adaptive capability to extract fuzzy inference modules from observation data through the learning process. The proposed MFIS is based on the structural similarity to Tagaki-Sugeno fuzzy models and a modular neural architecture. The learning of MFIS is done by assigning new fuzzy inference modules and by updating the parameters of existing modules. The fuzzy inference modules consist of local model network and fuzzy gating network. The parameters of the MFIS are updated by the standard LMS algorithm. The performance of the MFIS is illustrated with adaptive control of a nonlinear dynamic system.

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Structurally Adaptive Fuzzy Radial Basis Function Networks (구조적으로 적응하는 퍼지 RBF 신경회로망)

  • Choi, Jong-Soo;Lee, Gi-Bum;Kwon, Oh-Shin
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2203-2205
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    • 1998
  • This paper describes fuzzy radial basis function networks(FRBFN) extracting fuzzy rules through the learning from training data set. The proposed FRBFN is derived from the functional equivalence between RBF networks and fuzzy inference systems. The FRBFN learn by assigning new fuzzy rules and updating the parameters of existing fuzzy rules. The parameters of the FRBFN are adjusted using the standard LMS algorithm. The performance of the FRBFN is illustrated with function approximation and system identification.

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Nonlinear Approximation in High-Dimensional Spaces Using Tree-Structured Intelligent Systems (수목구조 지능시스템을 이용한 고차원 공간 위에서의 비선형 근사)

  • 길준민;정창호;강성훈;박주영;박대희
    • Journal of the Korean Institute of Intelligent Systems
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    • v.6 no.3
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    • pp.25-36
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    • 1996
  • Conventional radial-basis-function networks and fuzzy systems have serious problems in dealing with the non1inea:r approximations on high-dimensional spaces due to the explosive increase of the number of hidden nodes or fuzzy IF-THEN rules. In order to avoid such problems, this paper proposes a tree-structured intelligent system in which semi-local basis functions form its basic elements, and develops a training algorithm for the proposed system based on the modified genetic algorithm and LMS rule. Theoretical analysis is performed on the approximation capability of the proposed system, together with experimental studies which demonstrate the effectiveness of the developed methodology.

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Tree-Structured Fuzzy System (트리구조 퍼지시스템)

  • 정창호;강성훈;박주영;박대희
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1996.10a
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    • pp.154-157
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    • 1996
  • Conventional fuzzy systems have serious problems in dealing with the nonlinear approximations on high-dimensional spaces due to the explosive increase of the number of fuzzy IF-THEN rules. In order to avoid such problems, this paper proposes a tree-structured fuzzy system in which semi-local basis functions form its basic elements, and develops a training algorithm for the proposed system based on the evolution program and LMS rule. The experimental studies demonstrate the effectiveness of the developed methodology.

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Takagi-Sugeno Fuzzy Model for Greenhouse Climate

  • Imen Haj Hamad;Amine Chouchaine;Hajer Bouzaouache
    • International Journal of Computer Science & Network Security
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    • v.24 no.7
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    • pp.24-30
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    • 2024
  • This paper investigates the identification and modeling of a climate greenhouse. Given real climate data from greenhouse installed in the LAPER laboratory in Tunisia, the objective of this paper is to propose a solution of the problem of nonlinear time variant inputs and outputs of greenhouse internal climate. Based on fuzzy logic technique combined with least mean squares (lms) a robust greenhouse climate model for internal temperature prediction is proposed. The simulation results are presented to demonstrate the effectiveness of the identification approach and the power of the implemented Takagi-Sugeno Fuzzy model based Algorithm.

Multiple-Channel Active Noise Control by ANFIS and Independent Component Analysis without Secondary Path Modeling

  • Kim, Eung-Ju;Lee, Sang-yup;Kim, Beom-Soo;Lim, Myo-Taeg
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.22.1-22
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    • 2001
  • In this paper we present Multiple-Channel Active Noise Control[ANC] system by employing Independent Component Analysis[ICA] and Adaptive Network Fuzzy Inference System[ANFIS]. ICA is widely used in signal processing and communication and it use prewhiting and appropriate choice of non-linearities, ICA can separate mixed signal. ANFIS controller is trained with the hybrid learning algorithm to optimize its parameters for adaptively canceling noise. This new method which minimizes a statistical dependency of mutual information(MI) in mixed low frequency noise signal and there is no need to secondary path modeling. The proposed implementations achieve more powerful and stable noise reduction than Filtered-X LMS algorithms which is needed for LTI assumption and precise secondary error

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