• 제목/요약/키워드: Neural network identification

검색결과 565건 처리시간 0.029초

최적 구조 신경 회로망을 이용한 선박용 안정화 위성 안테나 시스템의 모델링 (Modelling of a Shipboard Stabilized Satellite Antenna System Using an Optimal Neural Network Structure)

  • 김민정;황승욱
    • 한국항해항만학회지
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    • 제28권5호
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    • pp.435-441
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    • 2004
  • 본 논문은 비선형성을 많이 내포하고 있어 수학적으로 모델링 하기 어려운 선박용 안정화 위성 안테나 시스템을 모델링하기 위해서, 신경 회로망의 오차 및 응답시간을 최소로 하는 최적 구조 신경 회로망 모델을 도출하고 이를 적용하고자 한다. 오차와 응답시간을 최소화하기 위해 유전알고리즘을 이용하여 신경 회로망 구조를 설계하였다. 안테나 시스템으로부터 얻어진 입출력 데이터에 거하여 본 논문에서 제안한 식별기를 이용하여 안테나 시스템을 식별하였으며, 실제 선박의 운동 성분에 대해서도 시스템을 잘 표현할 수 있는 최적 구조 신경 회로 기반 시스템 식별기를 얻을 수 있었다. 실제 실험을 통해서, 최적 신경회로망 구조가 안테나 시스템 식별에 효과적인 것을 알 수 있었다.

자기 회귀 웨이블릿 신경 회로망을 이용한 다이나믹 시스템의 동정: 적응 학습률 기반 수렴성 분석 (Identification of Dynamic Systems Using a Self Recurrent Wavelet Neural Network: Convergence Analysis Via Adaptive Learning Rates)

  • 유성진;최윤호;박진배
    • 제어로봇시스템학회논문지
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    • 제11권9호
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    • pp.781-788
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    • 2005
  • This paper proposes an identification method using a self recurrent wavelet neural network (SRWNN) for dynamic systems. The architecture of the proposed SRWNN is a modified model of the wavelet neural network (WNN). But, unlike the WNN, since a mother wavelet layer of the SRWNN is composed of self-feedback neurons, the SRWNN has the ability to store the past information of the wavelet. Thus, in the proposed identification architecture, the SRWNN is used for identifying nonlinear dynamic systems. The gradient descent method with adaptive teaming rates (ALRs) is applied to 1.am the parameters of the SRWNN identifier (SRWNNI). The ALRs are derived from the discrete Lyapunov stability theorem, which are used to guarantee the convergence of an SRWNNI. Finally, through computer simulations, we demonstrate the effectiveness of the proposed SRWNNI.

Iterative neural network strategy for static model identification of an FRP deck

  • Kim, Dookie;Kim, Dong Hyawn;Cui, Jintao;Seo, Hyeong Yeol;Lee, Young Ho
    • Steel and Composite Structures
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    • 제9권5호
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    • pp.445-455
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    • 2009
  • This study proposes a system identification technique for a fiber-reinforced polymer deck with neural networks. Neural networks are trained for system identification and the identified structure gives training data in return. This process is repeated until the identified parameters converge. Hence, the proposed algorithm is called an iterative neural network scheme. The proposed algorithm also relies on recent developments in the experimental design of the response surface method. The proposed strategy is verified with known systems and applied to a fiber-reinforced polymer bridge deck with experimental data.

비선형 시스템의 동정을 위한 안정한 웨이블릿 기반 퍼지 뉴럴 네트워크 (Stable Wavelet Based Fuzzy Neural Network for the Identification of Nonlinear Systems)

  • 오준섭;박진배;최윤호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2681-2683
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    • 2005
  • In this paper, we present the structure of fuzzy neural network(FNN) based on wavelet function, and apply this network structure to the identification of nonlinear systems. For adjusting the shape of membership function and the connection weights, the parameter learning method based on the gradient descent scheme is adopted. And an approach that uses adaptive learning rates is driven via a Lyapunov stability analysis to guarantee the fast convergence. Finally, to verify the efficiency of our network structure. we compare the Identification performance of proposed wavelet based fuzzy neural network(WFNN) with those of the FNN, the wavelet fuzzy model(WFM) and the wavelet neural network(WNN) through the computer simulation.

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신경망을 이용한 코히런트발전기의 선정 (Identification of coherent generators for dynamic equivalents using artificial neural network)

  • 임성정;한성호;윤용한;김재철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
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    • pp.3-5
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    • 1993
  • This paper presents a identification techniques of coherent generators for dynamic equivalents using artificial neural networks. In the developed neural network, inputs are the power system parameters which have a property of coherency. Outputs of the neural network are coherency and error indices which are derived from density measure concept. The learning of developed neural network is carried out by means of error back-propagation algorithm. Identification of coherent generators are implemented by proposed grouping algorithm using coherency and error indices. The proposed method is confirmed by simulations for 39-bus New England system.

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인공신경망을 이용한 지연시간이 일정치 않은 시스템의 제어 (Neural network-based control for uneven delay-time systems)

  • 이미경;이지홍
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.446-449
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    • 1997
  • We propose a control law in discrete time domain of the bilateral feedback teleoperation system using neural network and the reference model type of adaptive control. Different from traditional teleoperation systems, the transmission time delay irregularly changes. The proposed control method controls master and slave systems through identification of master and slave models using neural networks.

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치아 윤곽선 정보를 이용한 신경회로망 기반 신원 확인 방안 (Neural Network-Based Human Identification Using Teeth Contours)

  • 박상진;박형준
    • 한국CDE학회논문집
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    • 제18권4호
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    • pp.275-282
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    • 2013
  • This paper proposes a method for human identification using teeth contours extracted from dental images that are captured from the frontal views of subjects each of who opens his or her mouth slightly. Each dental image has a black-colored region containing the subject's teeth contours which are usually different from subject to subject. This means that this black-colored region has bio-mimetic information useful for human identification. The basic idea of the method is to extract the upper and lower teeth contours from the dental image of each subject and to encode their geometric patterns using a back-propagation neural network model. After acquiring 400 teeth images form 10 university students, we used 300 images for the training data of the neural network model and 100 images for its verification. Experimental results have shown that the proposed neural network-based method can be used as an alternative solution for identification among a small group of humans with a low cost and simple setup.

Hybrid 리커런트 신경망을 이용한 시스템 식별 (System Identification Using Hybrid Recurrent Neural Networks)

  • 최한고;고일환;김종인
    • 융합신호처리학회논문지
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    • 제6권1호
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    • pp.45-52
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    • 2005
  • 동적 신경망은 temporal 신호처리가 요구되는 여러 분야에 사용되어 왔다. 본 논문에서는 다층 리커런트 신경망(RNN)의 동특성을 더 향상시키기 위해 지역 궤환 신경망(LRNN)과 광역 궤환 신경망(GRNN)으로 구성된 합성 신경망을 사용하여 시스템 식별을 다루고 있다. 합성 신경망의 구조는 LRNN으로 IIR-MLP를, GRNN으로 Elman RNN을 결합하고 있다. 합성신경망은 선형과 비선형 시스템 식별을 통해 평가되었으며 상대적인 성능평가를 위해 Elman RNN과 IIR-MLP 신경망과 비교하고 있다. 시뮬레이션 결과에 의하면 합성 신경망은 학습속도와 정확도에서 더 우수하게 동작하였으며, 이러한 사실은 비선형 시스템 식별에 있어서 합성 신경망이 기존의 다층 리커런트 신경망보다 더 효과적인 신경망이 될 수 있음을 보여주었다.

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전력계토의 불량데이타 검출에서의 신경회로망 응용에 관한 연구 (Neural Nerwork Application to Bad Data Detection in Power Systems)

  • 박준호;이화석
    • 대한전기학회논문지
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    • 제43권6호
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    • pp.877-884
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    • 1994
  • In the power system state estimation, the J(x)-index test and normalized residuals ${\gamma}$S1NT have been the presence of bad measurements and identify their location. But, these methods require the complete re-estimation of system states whenever bad data is identified. This paper presents back-propagation neural network medel using autoregressive filter for identification of bad measurements. The performances of neural network method are compared with those of conventional mehtods and simulation results show the geed performance in the bad data identification based on the neural network under sample power system.