• Title/Summary/Keyword: RBF 망

Search Result 103, Processing Time 0.039 seconds

Design of Adaptive Linearization Controller for Nonlinear System Using RBF Networks (RBF 회로망을 이용한 비선형 시스템의 적응 선형화 제어기의 설계)

  • 탁한호;김명규
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.5 no.3
    • /
    • pp.525-531
    • /
    • 2001
  • The paper demonstrates that RBF(Radial Basis Function) networks can be used effective for the identification of inverted pendulum system. With the parallel arrangement of the RBF networks controller and PD controller, some characteristics were compared through simulation performance.

  • PDF

Recognition of Unconstrained Handwritten Digits Using Raised Cosine RBF Neural Networks (Raised Cosine RBF 신경망을 이용한 무제약 필기체 숫자 인식)

  • 박준근;김상희;박원우
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.3 no.1
    • /
    • pp.48-53
    • /
    • 2002
  • In this paper, we presented a new approach to the recognition of unconstrained handwritten numerals using an improved RBF(Radial Basis Function) Neural Networks. The RBF Neural Networks used Raised Cosine as a basis function to improve discrimination and reduce processing time. The performance of Raised Cosine RBF Neural Networks classifier was evaluated using totally unconstrained handwritten numeral database of Concordia University, Montreal, Canada, and the experimental results showed the recognition rate of 98.05%.

  • PDF

Hydrological Forecasting Based on Hybrid Neural Networks in a Small Watershed (중소하천유역에서 Hybrid Neural Networks에 의한 수문학적 예측)

  • Kim, Seong-Won;Lee, Sun-Tak;Jo, Jeong-Sik
    • Journal of Korea Water Resources Association
    • /
    • v.34 no.4
    • /
    • pp.303-316
    • /
    • 2001
  • In this study, Radial Basis Function(RBF) Neural Networks Model, a kind of Hybrid Neural Networks was applied to hydrological forecasting in a small watershed. RBF Neural Networks Model has four kinds of parameters in it and consists of unsupervised and supervised training patterns. And Gaussian Kernel Function(GKF) was used among many kinds of Radial Basis Functions(RBFs). K-Means clustering algorithm was applied to optimize centers and widths which ate the parameters of GKF. The parameters of RBF Neural Networks Model such as centers, widths weights and biases were determined by the training procedures of RBF Neural Networks Model. And, with these parameters the validation procedures of RBF Neural Networks Model were carried out. RBF Neural Networks Model was applied to Wi-Stream basin which is one of the IHP Representative basins in South Korea. 10 rainfall events were selected for training and validation of RBF Neural Networks Model. The results of RBF Neural Networks Model were compared with those of Elman Neural Networks(ENN) Model. ENN Model is composed of One Step Secant BackPropagation(OSSBP) and Resilient BackPropagation(RBP) algorithms. RBF Neural Networks shows better results than ENN Model. RBF Neural Networks Model spent less time for the training of model and can be easily used by the hydrologists with little background knowledge of RBF Neural Networks Model.

  • PDF

Robust Speed Control of AC Permanent Magnet Synchronous Motor using RBF Neural Network (RBF 신경회로망을 이용한 교류 동기 모터의 강인 속도 제어)

  • 김은태;이성열
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.40 no.4
    • /
    • pp.243-250
    • /
    • 2003
  • In this paper, the speed controller of permanent-magnet synchronous motor (PMSM) using the RBF neural (NN) disturbance observer is proposed. The suggested controller is designed using the input-output feedback linearization technique for the nominal model of PMSM and incorporates the RBF NN disturbance observer to compensate for the system uncertainties. Because the RBF NN disturbance observer which estimates the variation of a system parameter and a load torque is employed, the proposed algorithm is robust against the uncertainties of the system. Finally, the computer simulation is carried out to verify the effectiveness of the proposed method.

Self Organizing RBF Neural Network Equalizer (자력(自力) RBF 신경망 등화기)

  • Kim, Jeong-Su;Jeong, Jeong-Hwa
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.39 no.1
    • /
    • pp.35-47
    • /
    • 2002
  • This paper proposes a self organizing RBF neural network equalizer for the equalization of digital communications. It is the most important for the equalizer using the RBF neural network to estimate the RBF centers correctly and quickly, which are the desired channel states. However, the previous RBF equalizers are not used in the actual communication system because of some drawbacks that the number of channel states has to be known in advance and many centers are necessary. Self organizing neural network equalizer proposed in this paper can implement the equalization without prior information regarding the number of channel states because it selects RBF centers among the signals that are transmitted to the equalizer by the new addition and removal criteria. Furthermore, the proposed equalizer has a merit that is able to make a equalization with fewer centers than those of prior one by the course of the training using LMS and clustering algorithm. In the linear, nonlinear and standard telephone channel, the proposed equalizer is compared with the optimal Bayesian equalizer for the BER performance, the symbol decision boundary and the number of centers. As a result of the comparison, we can confirm that the proposed equalizer has almost similar performance with the Bavesian enualizer.

Learning RBF Neural Networks by Active Data Selection (능동적인 데이터 선택에 의한 RBF 신경망의 학습)

  • 박상욱;장병탁
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2000.04b
    • /
    • pp.478-480
    • /
    • 2000
  • 본 논문에서는 데이터를 능동적으로 선택하고, 그 데이터에 맞추어 RBF 은닉 뉴런을 증가시키는 신경망을 제안한다. 현재의 신경망에 대해서 가장 학습이 어려운 데이터를 선택해서 신경망을 학습하고, 학습한 신경망에 대해서 다시 에러가 가장 큰 데이터를 뽑아서 학습시키는 과정을 반복한다. 5개의 실세계 데이터에 대해 실험을 해보고, Platt이 제안한 RAN과 성능을 비교한다. 점진적으로 임계 데이터를 선택해서 학습을 함으로써, 전체 데이터를 다 사용하지도 않고도, 전체 데이터를 다 사용한 경우와 비슷한 성능을 보임을 실험을 통해서 알 수 있다.

  • PDF

Software Maintenance Cost Estimation using RBF Network (RBF망을 이용한 소프트웨어 유지보수 비용 추정)

  • 박주석;정기원
    • Journal of KIISE:Software and Applications
    • /
    • v.31 no.5
    • /
    • pp.555-562
    • /
    • 2004
  • Software industry has put more emphasis on maintenance and enhancement work than on the new development. The existing effort estimation models can still be applied to maintenance projects, though modifications are needed. This paper suggests a way to estimate the size of a maintenance project from the regression analysis of ISBSG's benchmarking data. First of all, among the 3 elements(addition, modification and deletion of the program) which influences the software cost, we selected and classified 4 groups from a total of 8 which shows actual maintenance cost from ISBSG's data. Moreover, we developed statistical model and a model which uses RBF(Radial Basis Function) Network and after evaluating each functions we concluded that the RBF Network is superior to the statistical model.

FCM-based RBF Network Using Fuzzy Control Method (퍼지 제어 기법을 이용한 FCM 기반 RBF 네트워크)

  • Kim, Tae-Hyung;Park, Choong-Shik;Kim, Kwang-Baek
    • Proceedings of the Korean Society of Computer Information Conference
    • /
    • 2008.06a
    • /
    • pp.149-154
    • /
    • 2008
  • FCM 기반 RBF 네트워크는 서로 다른 학습 구조가 결합된 혼합형 모델로서, 입력층과 중간층의 학습 구조는 FCM 알고리즘을 적용하고, 중간층과 출력층 사이의 학습 구조는 Max_Min 신경망을 적용한다. 입력층과 중간층의 학습시 입력벡터와 중간층의 노드중에서 중심과 입력벡터간의 가장 가까운 노드를 승자 노드로 선택하여 출력층으로 전달한다. 그리고 중간층과 출력층 사이의 학습 구조는 Max_Min 신경망을 적용하여 중간층의 승자 뉴런이 출력층의 입력벡터로 적용한다. 하지만 많은 패턴이 입력벡터로 제시될 경우 학습 성능이 저하되는 단점이 있다. 따라서 본 논문에서는 중간층과 출력층의 학습 구조인 Max_Min 알고리즘의 학습 성능을 개선시키기 위해 퍼지 제어시스템을 이용하여 학습률을 동적으로 조정하는 퍼지 제어 기법을 이용한 FCM 기반 RBF 네트워크를 제안한다. 제안된 방법의 학습 성능을 평가하기 위하여 컨테이너 영상에서 추출한 숫자, 영문 식별자를 학습 데이터로 적용한 결과, 기존의 ART2 기반 RBF 네트워크보다 학습 시간이 적게 소요되고, 학습의 수렴성이 개선된 것을 확인하였다.

  • PDF

Neural Network Based Land Cover Classification Technique of Satellite Image for Pollutant Load Estimation (신경망 기반의 오염부하량 산정을 위한 위성영상 토지피복 분류기법)

  • Park, Sang-Young;Ha, Sung-Ryong
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2001.12a
    • /
    • pp.1-4
    • /
    • 2001
  • The classification performance of Artificial Neural Network (ANN) and RBF-NN was compared for Landsat TM image. The RBF-NN was validated for three unique landuse types (e.g. Mixed landuse area, Cultivated area, Urban area), different input band combinations and classification class. The bootstrap resampling technique was employed to estimate the confidence intervals and distribution for unit load, The pollutant generation was varied significantly according to the classification accuracy and percentile unit load applied. Especially in urban area, where mixed landuse is dominant, the difference of estimated pollutant load is largely varied.

  • PDF

Improving Estimative Capability of Software Development Effort using Radial Basis Function Network (RBF 망 이용 소프트웨어 개발 노력 추정 성능향상)

  • Lee, Sang-Un;Park, Yeong-Mok;Park, Jae-Hong
    • The KIPS Transactions:PartD
    • /
    • v.8D no.5
    • /
    • pp.581-586
    • /
    • 2001
  • An increasingly important facet of software development is the ability to estimated the associated coast and effort of development early in the development life cycle. In spite of the most generally sued procedures for estimation of the software development effort and cost were linear regression analysis. As a result of the software complexity and various development environments, the software effort and cost estimates that are grossly inaccurate. The application of nonlinear methods hold the greatest promise for achieving this objects. Therefore this paper presents an RBF (radial basis function) network model that is able to represent the nonlinear relation for software development effort, The research describes appropriate RBF network modeling in the context of a case study for 24 software development projects. Also, this paper compared the RBF network model with a regression analysis model. The RBF network model is the most accuracy of all.

  • PDF