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1.
模糊ART神经网络在运动目标识别中的应用   总被引:1,自引:0,他引:1  
本文在讨论模糊ART神经网络及其算法的基础上,研究和提出了一种三维运动目标识别方法,利用模糊ART神经网络对运动目标的目标侧面图形进行学习和模式识别。模拟实验表明了该方法的有效性。  相似文献   

2.
为解决T akag i-Sugeno型模糊神经网络在控制多变量系统时的规则组合爆炸问题,提出一种误差前馈补偿的模糊神经网络控制方案,有效实现了三级倒立摆的稳定控制。该控制方案适用对状态变量可按性质和重要程度划分的多变量系统的控制,大大减少了模糊神经网络控制器的规则数,有利于利用专家的控制经验,具有良好的鲁棒性和非线性适应能力。  相似文献   

3.
针对变论域模糊控制,提出一种新的自组织结构的变论域模糊控制方法。自组织结构算法可以调整变论域模糊系统结构以及动态获得模糊规则,进一步减小变论域模糊控制项的稳态逼近误差。通过进一步理论分析可知,自组织结构算法仅仅保证了系统瞬时的切换是平稳的,但不能保证系统的闭环稳定性。给出了所提出控制方法的适用条件。通过与固定模糊系统结构的变论域模糊控制比较,仿真结果表明,所提出控制方法不仅使得系统的稳态跟踪误差更平稳,而且使得输入控制信号更加平滑。  相似文献   

4.
一类非线性不确定系统的鲁棒自适应模糊跟踪控制   总被引:2,自引:0,他引:2  
针对一类单输入单输出非线性不确定系统,提出一种稳定的间接自适应模糊控制方法。该方法考虑了跟踪误差和逼近误差对参数自适应律的共同影响,并对模糊逼近误差和外扰采用H∞补偿控制。仿真结果表明本文所提出的方法具有良好的跟踪性能。  相似文献   

5.
本文考虑误差为自回归过程的固定效应面板数据部分线性回归模型的估计.对于固定效应短时间序列面板数据,通常使用的自回归误差结构拟合方法不能得到一个一致的自回归系数估计量.因此本文提出一个替代估计并证明所提出的自回归系数估计是一致的,且该方法在任何阶的自回归误差下都是可行的.进一步,通过结合B样条近似,截面最小二乘虚拟变量(LSDV)技术和自回归误差结构的一致估计,本文使用加权截面LSDV估计参数部分和加权B样条(BS)估计非参数部分,所得到的加权截面LSDV估计量被证明是渐近正态的,且比可忽略误差的自回归结构模型更渐近有效.另外,加权BS估计量被推导出具有渐近偏差和渐近正态性.模拟研究和实际例子相应地说明了所估计程序的有限样本性.  相似文献   

6.
为了进一步提高短时交通流量预测的精度,提出了一种粒子群算法的模糊神经网络组合预测模型,模糊神经网络融合了神经网络的学习机制和模糊系统的语言推理能力等优点,弥补各自不足,将自回归求和滑动平均(ARIMA)和灰色Verhulst模型进行初步预测,并将两种初步预测的结果作为模糊神经网络的输入,构建基于改进模神经网络的组合预测模型,在此基础上进行训练和预测,其中模糊神经网络的相关参数由改进粒子群来优化,利用本方法来对南京市汉中路短时交通流量进行预测,结论表明:方法充分发挥了单一模型的优势,比单一的预测模型更加精确,是短时交通流量预测的一个有效方法。  相似文献   

7.
针对一类具有不确定性、多重时延和状态未知的复杂非线性系统,把模糊T-S模型和RBF神经网络结合起来,提出了一种基于观测器的跟踪控制方案.首先,应用模糊T-S模型对非线性系统建模,设计观测器用来观测系统状态,并由线性矩阵不等式得到模糊模型的控制律;其次,构建了自适应RBF神经网络,应用自适应RBF神经网络作为补偿器来补偿建模误差和不确定非线性部分.证明了闭环系统满足期望的跟踪性能.示例仿真结果表明了该方案的有效性.  相似文献   

8.
针对自抗扰控制(AIDRC)多参数不易整定的问题,提出了一种基于二次函数的非线性PID(NLPID)控制律.该方法用二次函数模拟PID增益参数随误差变化的规律曲线,构造了一个非线性PID神经网络模型,利用最速下降法对各模拟曲线的系数进行在线调整,实现了基于神经网络的自适应自抗扰控制.仿真结果表明,与常规ADRC控制方法相比,文章方法减少了ADRC需调整的参数,并具有较好的控制效果.  相似文献   

9.
模糊神经网络理论研究综述   总被引:22,自引:1,他引:22  
本文对于近年来受到普遍重视的前向模糊神经网络及有反馈的模糊神经网络的性质、学习算法及应用等方面的研究进行了较为详尽的综述,分析了所取得的主要成果及其特点,并指出了今后模糊神经网络理论研究中有待解决的许多问题。  相似文献   

10.
《模糊系统与数学》2021,35(4):72-79
本文研究了一类具有扇形死区的分数阶神经网络系统的同步问题,提出了一种自适应模糊控制方法。首先,采用模糊逻辑系统对不确定的非线性函数进行逼近,通过分数阶自适应定律来更新模糊系统的参数。其次,基于分数阶李雅普诺夫稳定性准则,设计了一种自适应模糊变结构控制器,该控制器可以保证系统状态同步误差收敛到原点的足够小的邻域。最后,通过数值仿真验证本文方法的有效性。  相似文献   

11.
A neural fuzzy control system with structure and parameter learning   总被引:8,自引:0,他引:8  
A general connectionist model, called neural fuzzy control network (NFCN), is proposed for the realization of a fuzzy logic control system. The proposed NFCN is a feedforward multilayered network which integrates the basic elements and functions of a traditional fuzzy logic controller into a connectionist structure which has distributed learning abilities. The NFCN can be constructed from supervised training examples by machine learning techniques, and the connectionist structure can be trained to develop fuzzy logic rules and find membership functions. Associated with the NFCN is a two-phase hybrid learning algorithm which utilizes unsupervised learning schemes for structure learning and the backpropagation learning scheme for parameter learning. By combining both unsupervised and supervised learning schemes, the learning speed converges much faster than the original backpropagation algorithm. The two-phase hybrid learning algorithm requires exact supervised training data for learning. In some real-time applications, exact training data may be expensive or even impossible to obtain. To solve this problem, a reinforcement neural fuzzy control network (RNFCN) is further proposed. The RNFCN is constructed by integrating two NFCNs, one functioning as a fuzzy predictor and the other as a fuzzy controller. By combining a proposed on-line supervised structure-parameter learning technique, the temporal difference prediction method, and the stochastic exploratory algorithm, a reinforcement learning algorithm is proposed, which can construct a RNFCN automatically and dynamically through a reward-penalty signal (i.e., “good” or “bad” signal). Two examples are presented to illustrate the performance and applicability of the proposed models and learning algorithms.  相似文献   

12.
We describe a system for implementing fuzzy logic controllers using a neural network. A significant aspect of this system is that the linguistic values associated with the fuzzy control rules can be general concave continuous fuzzy subsets. By using structures suggested by the fuzzy logic framework, we simplify the learning requirements. On the other hand the adaptive aspect of the neural framework allows for the necessary learning.  相似文献   

13.
A kind of real-time stable self-learning fuzzy neural network (FNN) control system is proposed in this paper. The control system is composed of two parts: (1) A FNN controller which use genetic algorithm (GA) to search optimal fuzzy rules and membership functions for the unknown controlled plant; (2) A supervisor which can guarantee the stability of the control system during the real-time learning stage, since the GA has some random property which may cause control system unstable. The approach proposed in this paper combine a priori knowledge of designer and the learning ability of FNN to achieve optimal fuzzy control for an unknown plant in real-time. The efficiency of the approach is verified by computer simulation.  相似文献   

14.
A fuzzy traffic signal controller uses simple “if–then” rules which involve linguistic concepts such as medium or long, presented as membership functions. In neurofuzzy traffic signal control, a neural network adjusts the fuzzy controller by fine-tuning the form and location of the membership functions. The learning algorithm of the neural network is reinforcement learning, which gives credit for successful system behavior and punishes for poor behavior; those actions that led to success tend to be chosen more often in the future. The objective of the learning is to minimize the vehicular delay caused by the signal control policy. In simulation experiments, the learning algorithm is found successful at constant traffic volumes: the new membership functions produce smaller vehicular delay than the initial membership functions.  相似文献   

15.
The Kohonen self organizing neural network has been applied to an increasingly wider range of application problems that traditionally have been the domain of statistical and operational research techniques, such as data clustering and classification, and optimization and control. This Kohonen network is bestowed with a number of unique strengths which are, unfortunately, matched by an equally formidable set of limitations due its learning algorithm. There have been extensive studies over the last decade to extend the Kohonen neural network using heuristic and optimization approaches. This paper provides a comprehensive survey of the research efforts directed to enhancing the Kohonen self organizing neural network and its learning algorithm. We also point out some research directions for pursuing further improvements.  相似文献   

16.
Evaluation of fuzzy regression models by fuzzy neural network   总被引:1,自引:0,他引:1  
In this paper, a novel hybrid method based on fuzzy neural network for approximate fuzzy coefficients (parameters) of fuzzy linear and nonlinear regression models with fuzzy output and crisp inputs, is presented. Here a neural network is considered as a part of a large field called neural computing or soft computing. Moreover, in order to find the approximate parameters, a simple algorithm from the cost function of the fuzzy neural network is proposed. Finally, we illustrate our approach by some numerical examples.  相似文献   

17.
The fuzzified neural network based on fuzzy number operations is presented as a powerful modelling tool here. We systematically introduce ideas and concepts of a novel neural network based on fuzzy number operations. First we suggest how to compute the results of addition, subtraction, multiplication and division for two fuzzy numbers. Second we propose a learning algorithm, and present some ideas about the choice of fuzzy weights and fuzzy biases and a numerical scheme for the calculation of outputs of the fuzzified neural network. Finally, we show some results of computer simulations.  相似文献   

18.
Recently, fuzzy linear regression is considered by Mosleh et al. [1]. In this paper, a novel hybrid method based on fuzzy neural network for approximate fuzzy coefficients (parameters) of fuzzy polynomial regression models with fuzzy output and crisp inputs, is presented. Here a neural network is considered as a part of a large field called neural computing or soft computing. Moreover, in order to find the approximate parameters, a simple algorithm from the cost function of the fuzzy neural network is proposed. Finally, we illustrate our approach by some numerical examples.  相似文献   

19.
A novel self-organizing wavelet cerebellar model articulation controller (CMAC) is proposed. This self-organizing wavelet CMAC (SOWC) can be viewed as a generalization of a self-organizing neural network and of a conventional CMAC, and it has better generalizing, faster learning and faster recall than a self-organizing neural network and a conventional CMAC. The proposed SOWC has the advantages of structure learning and parameter learning simultaneously. The structure learning possesses the ability of on-line generation and elimination of layers to achieve optimal wavelet CMAC structure, and the parameter learning can adjust the interconnection weights of wavelet CMAC to achieve favorable approximation performance. Then a SOWC backstepping (SOWCB) control system is proposed for the nonlinear chaotic systems. This SOWCB control system is composed of a SOWC and a fuzzy compensator. The SOWC is used to mimic an ideal backstepping controller and the fuzzy compensator is designed to dispel the residual of approximation errors between the ideal backstepping controller and the SOWC. Moreover, the parameters of the SAWCB control system are on-line tuned by the derived adaptive laws in the Lyapunov sense, so that the stability of the feedback control system can be guaranteed. Finally, two application examples, a Duffing–Holmes chaotic system and a gyro chaotic system, are used to demonstrate the effectiveness of the proposed control method. The simulation results show that the proposed SAWCB control system can achieve favorable control performance and has better tracking performance than a fuzzy neural network control system and a conventional adaptive CMAC.  相似文献   

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