• Title/Summary/Keyword: RBF network

Search Result 242, Processing Time 0.032 seconds

An Neural Network Direct Controller For Nonlinear Systems (신경망을 이용한 비선형 동적 시스템의 최적 제어에 관한 연구)

  • Jeon, Jeong-Chay;Lee, Hyung-Chung;Ryu, In-Ho;Kim, Hee-Sook
    • Proceedings of the KIEE Conference
    • /
    • 2004.07d
    • /
    • pp.2498-2500
    • /
    • 2004
  • In this paper, a direct controller for nonlinear plants using a neural network is presented. The controller is composed of an approximate controller and a neural network auxiliary controller. The approximate controller gives the rough control and the neural network controller gives the complementary signal to further reduce the output tracking error. This method does not put too much restriction on the type of nonlinear plant to be controlled. In this method, a RBF neural network is trained and the system has a stable performance for the inputs it has been trained for. Simulation results show that it is very effective and can realize a satisfactory control of the nonlinear system.

  • PDF

A study of improvement of control performance of ship by fuzzy neutral network (퍼지 신경회로망에 의한 선박의 제어성능 개선에 관한 연구)

  • Kang, Chang-Nam
    • Proceedings of the KIEE Conference
    • /
    • 2008.07a
    • /
    • pp.671-672
    • /
    • 2008
  • Hybrid intelligent technique is used in ship steering control. It can make full use of the advantage of all kinds of intelligent algorithms. This provides an efficient way for this paper. An RBF neural network and GA optimization are employed in a fuzzy neural controller to deal with the nonlinearity, time varying and uncertain factors. Utilizing the designed network to substitute the conventional fuzzy inference, the rule base and membership functions can be auto-adjusted by GA optimization. The parameters of neural network can be decreased by using union-rule configuration in the hidden layer of the network. The ship control quality is effectively improved in case of appending additional sea state disturbance. The performance of controller is evaluated by the system simulation using Matlab.

  • PDF

TCSC Nonlinear Adaptive Damping Controller Design Based on RBF Neural Network to Enhance Power System Stability

  • Yao, Wei;Fang, Jiakun;Zhao, Ping;Liu, Shilin;Wen, Jinyu;Wang, Shaorong
    • Journal of Electrical Engineering and Technology
    • /
    • v.8 no.2
    • /
    • pp.252-261
    • /
    • 2013
  • In this paper, a nonlinear adaptive damping controller based on radial basis function neural network (RBFNN), which can infinitely approximate to nonlinear system, is proposed for thyristor controlled series capacitor (TCSC). The proposed TCSC adaptive damping controller can not only have the characteristics of the conventional PID, but adjust the parameters of PID controller online using identified Jacobian information from RBFNN. Hence, it has strong adaptability to the variation of the system operating condition. The effectiveness of the proposed controller is tested on a two-machine five-bus power system and a four-machine two-area power system under different operating conditions in comparison with the lead-lag damping controller tuned by evolutionary algorithm (EA). Simulation results show that the proposed damping controller achieves good robust performance for damping the low frequency oscillations under different operating conditions and is superior to the lead-lag damping controller tuned by EA.

Performance comparison of SVM and ANN models for solar energy prediction (태양광 에너지 예측을 위한 SVM 및 ANN 모델의 성능 비교)

  • Jung, Wonseok;Jeong, Young-Hwa;Park, Moon-Ghu;Lee, Chang-Kyo;Seo, Jeongwook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2018.10a
    • /
    • pp.626-628
    • /
    • 2018
  • In this paper, we compare the performances of SVM (Support Vector Machine) and ANN (Artificial Neural Network) machine learning models for predicting solar energy by using meteorological data. Two machine learning models were built by using fifteen kinds of weather data such as long and short wave radiation average, precipitation and temperature. Then the RBF (Radial Basis Function) parameters in the SVM model and the number of hidden layers/nodes and the regularization parameter in the ANN model were found by experimental studies. MAPE (Mean Absolute Percentage Error) and MAE (Mean Absolute Error) were considered as metrics for evaluating the performances of the SVM and ANN models. Sjoem Simulation results showed that the SVM model achieved the performances of MAPE=21.11 and MAE=2281417.65, and the ANN model did the performances of MAPE=19.54 and MAE=2155345.10776.

  • PDF

Initial Optimization of the RBFN with Time-Frequency Localization Using Genetic Algorithm (유전 알고리즘과 시간-주파수 지역화를 이용한 방사 기준 함수망의 초기 최적화)

  • 김성주;서재용;김용택;조현찬;전홍태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2001.12a
    • /
    • pp.221-224
    • /
    • 2001
  • In this paper, we propose the initial optimized structure of the Radial Basis Function Network which is more simple in the part on the structure and converges more faster than Neural Network with the analysis method using Time-Frequency Localization and genetic algorithm. When we construct the hidden node with the Radial Basis Function whose localization is similar with an approximation target function in the plane of the Time and Frequency, we have initial structure of RBFN, After that, we evaluate the parameters of RBF in the network and the parameters needed for the network is more a few. Finally, we make a good decision of the initial structure having an ability of approximation.

  • PDF

Model Updating Using Radial Basis Function Neural Network (RBF 신경망을 이용한 모델개선법)

  • Kim, Kwang-Keun;Choi, Sung-Pil;Kim, Young-Chan;Yang, Bo-Suk
    • The KSFM Journal of Fluid Machinery
    • /
    • v.3 no.3 s.8
    • /
    • pp.19-24
    • /
    • 2000
  • It is well known that the finite element analysis often has an inaccuracy when it is in conflict with test results. Model updating is concerned with the correction of analytical model by processing records of response from test results. The famous one of the model updating methods is FRF sensitivity method. However, it has demerit that the solution is not unique. So, the neural network is recommended when an unique and exact solution is desired. The generalization ability of radial basis function neural network is used in model updating. As an application model, a cantilever and a rotor system are used. Specially the machined clearance($C_p$) of a journal bearing is updated.

  • PDF

Design of a Pseudo Gaussian Function Network Using Asymmetric Activation Functions

  • Kim, Byung-Man;Cho, Hyung-Suck
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.43.3-43
    • /
    • 2001
  • In conventional RBF network, the activation functions of hidden layers generally are symmetric functions like gaussian function. This has been considered to be one of the limiting factors for the network to speed up learning of actuately describing a given function. To avoid this criticism, we propose a pseudo gaussian function (PGF) whose deviation is changed according to the direction of incoming pattern. This property helps to estimate the given function more effectively with a minimal number of centers because of its flexibility of functional representation. A level set method is used to describe the asymmetric shape of deviation of the pseudo gaussian function. To demonstrate the performance of the proposed network ...

  • PDF

An Image Compression Method using Radial-Basis Function Networks (Radial-BAsis Function Networks를 이용한 영상 압축 방법)

  • Lee, Jae-Young;Kim, Hwang-Soo
    • Journal of KIISE:Software and Applications
    • /
    • v.27 no.9
    • /
    • pp.913-919
    • /
    • 2000
  • 본 논문에서는 인간 시지각을 고려한 새로운 영상 압축 방법을 제시한다. 영상의 화소의 값들이 x-y 평명상에서 정의된 3차원 곡면 위에 있는 점들로 가정하여, 영상을 곡면의 복잡도에 따라 나누고, 나누어진 각각의 곡면(영역)은 Radial-Basis Function (RBF)를 사용하여 근사화하는 방법으로 영상을 압축한다. 본 방법은 JPEG 압축 방법과 비슷한 압축율과 영상의 질을 얻을 수 있다.

  • PDF

Relation between Multidimensional Liner Interpolation and Regularization Networks

  • Om, Kyong-Sik;Kim, Hee-Chan;Min, Byoun-Goo
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 1997.11a
    • /
    • pp.128-133
    • /
    • 1997
  • This paper examines the relation between multidimensional linear interpolation ( MDI ) and regularization networks, and shows that and MDI is a special form of regularization networks. For this purpose we propose a triangular basis function ( TBF ) network. Also we verified the condition when our proposed TBF becomes a well-known radial basis function ( RBF ).

  • PDF

Stability Analysis of Visual Servoing with Sliding-mode Estimation and Neural Compensation

  • Yu Wen
    • International Journal of Control, Automation, and Systems
    • /
    • v.4 no.5
    • /
    • pp.545-558
    • /
    • 2006
  • In this paper, PD-like visual servoing is modified in two ways: a sliding-mode observer is applied to estimate the joint velocities, and a RBF neural network is used to compensate the unknown gravity and friction. Based on Lyapunov method and input--to-state stability theory, we prove that PD-like visual servoing with the sliding mode observer and the neuro compensator is robust stable when the gain of the PD controller is bigger than the upper bounds of the uncertainties. Several simulations are presented to support the theory results.