• 제목/요약/키워드: Fuzzy LMS Algorithm

검색결과 21건 처리시간 0.024초

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

  • 최종수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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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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외란 예측기가 포함된 슬라이딩 모드 퍼지 제어기의 응용 (Application of Sliding Mode fuzzy Control with Disturbance Prediction)

  • 김상범;윤정방;구자인
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 봄 학술발표회논문집
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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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비정상 잡음환경에서의 지능형 적응 능동소음제어 (Intelligent Adaptive Active Noise Control in Non-stationary Noise Environments)

  • 무향빈;고진석;임재열
    • 한국음향학회지
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    • 제32권5호
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    • pp.408-414
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    • 2013
  • 능동소음제어에서 널리 사용되는 FxLMS 알고리즘은 비정상 잡음환경에서 불안정하게 동작하는 경우가 있다. 이와 같은 문제를 해결하기 위하여, Sun과 Akhtar는 FxLMS 알고리즘의 갱신 과정에서 기준신호를 수정하는 방법을 제안하였다. 그러나 이들의 방법은 임펄스 노이즈가 발생할 경우 만족스러운 안정성을 보여주지 못하였다. 본 논문에서 제안된 알고리즘은 확률추정과 영교차율을 이용하여 능동소음제어의 안정성과 성능을 개선하였다. 또한 최적의 파라미터 선정을 위하여 퍼지 추론을 사용하였다. 제안된 방법의 실험결과 비정상 잡음환경에서 기존의 방법에 비하여 우수한 안정성과 빠른 수렴속도를 보여줬다.

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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    • 제17권1E호
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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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비선형 시스템 제어를 위한 모듈화 피지추론 시스템 (Modular Fuzzy Inference Systems for Nonlinear System Control)

  • 권오신
    • 한국지능시스템학회논문지
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    • 제11권5호
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    • pp.395-399
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    • 2001
  • 이 논문은 학습을 통해 관측 데이터로부터 퍼지 추론 모듈을 생성할 수 있는 적응 능력을 갖는 모듈화 퍼지추론 시스템을 제안한다. 제안한 시스템은 TS 퍼지모델과 모듈화 신경회로망의 구조적 유사성을 기초로 한다. 학습과정은 새로운 퍼지추론 모듈의 생성과 모듈 파라미터의 갱신으로 구성된다. 퍼지추론 모듈은 국부모델망과 퍼지 게이팅망으로 구성된다. 제안한 시스템의 파라미터들은 표준 LMS 알고리즘을 이용하여 최적화된다. 제안한 시스템의 성능은 비선형 동적 시스템 적응제어에의 응용을 통해서 입증된다.

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

  • 최종수;이기범;권오신
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 G
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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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수목구조 지능시스템을 이용한 고차원 공간 위에서의 비선형 근사 (Nonlinear Approximation in High-Dimensional Spaces Using Tree-Structured Intelligent Systems)

  • 길준민;정창호;강성훈;박주영;박대희
    • 한국지능시스템학회논문지
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    • 제6권3호
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    • pp.25-36
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    • 1996
  • 기존의 RBF 신경망 및 퍼지 시스템을 고차원 입력 공간 위에서의 비선형 근사에 적용할 경우 은닉 노드의 수혹은 퍼지 IF-THEN 규칙의 수가 기하급수적으로 증가한다. 본 논문에서는 이러한 문제점을 개선하기 위해 반국소 유닛을 기본 요소로 하는 수목구조지능시스템을 제안하고, 이를 효과적으로 학습하기 위하여 수정 유전자 알고리즘 및 LMS 규칙에 기반을 둔 학습 알고리즘을 개발한다. 제안된 시스템에 대한 근사 능력 해석이 수행되고, 실험적 고찰을 통하여 개발된 방법론의 유용성이 입증된다.

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트리구조 퍼지시스템 (Tree-Structured Fuzzy System)

  • 정창호;강성훈;박주영;박대희
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1996년도 추계학술대회 학술발표 논문집
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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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    • 제24권7호
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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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    • 제어로봇시스템학회 2001년도 ICCAS
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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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