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1.
把径向基函数(RBF)神经网络和网格结合起来,提出了一种能够并行处理数据和便于增量计算的智能聚类方法。介绍了网格聚类原理、RBF神经网络神经元的数量和基函数的选择,并针对数据聚集区域的位置辨识、提高分辨率和计算速度等问题,深入讨论了聚类策略与聚类算法。仿真表明了该方法的有效性。  相似文献   

2.
为了解决热式气体流量计测量电路中采用硬件温度补偿成本高且精度不够等问题,利用神经网络的特点,设计了一种基于径向基函数(RBF)神经网络的软件温度补偿方法.实验表明:通过RBF神经网络温度补偿,有效地抑制了温度对流量计测量结果的影响,实现了环境温度梯度变化下气体流量测量的准确性和稳定性,测量准确度达到1.0级,且重复性好.  相似文献   

3.
In this paper a new methodology for training radial basis function (RBF) neural networks is introduced and examined. This novel approach, called Fuzzy-OSD, could be used in applications, which need real-time capabilities for retraining neural networks. The proposed method uses fuzzy clustering in order to improve the functionality of the Optimum Steepest Descent (OSD) learning algorithm. This improvement is due to initialization of RBF units more precisely using fuzzy C-Means clustering algorithm that results in producing better and the same network response in different retraining attempts. In addition, adjusting RBF units in the network with great accuracy will result in better performance in fewer train iterations, which is essential when fast retraining of the network is needed, especially in the real-time systems. We employed this new method in an online radar pulse classification system, which needs quick retraining of the network once new unseen emitters detected. Having compared result of applying the new algorithm and Three-Phase OSD method to benchmark problems from Proben1 database and also using them in our system, we achieved improvement in the results as presented in this paper.  相似文献   

4.
针对热电偶信号处理中的非线性校正和冷端补偿等突出问题,利用径向基函数(RBF)神经网络构造双输入单输出的网络模型,并采用遗传算法对网络结构和参数进行优化训练,同时完成了热电偶测温中的非线性校正和冷端补偿。经仿真实验证明:该方法的测量误差减小至0.095%,在较大范围内提高了热电偶温度测量的精度。  相似文献   

5.
针对RBF神经网络隐含层节点数过多导致网络结构复杂的问题,提出了一种基于改进遗传算法(IGA)的RBF神经网络优化算法。利用IGA优化基于正交最小二乘法的RBF神经网络结构,通过对隐含层输出矩阵的列向量进行全局寻优,从而设计出结构更优的基于IGA的RBF神经网络(IGA-RBF)。将IGA-RBF神经网络的学习算法应用于电子元器件贮存环境温湿度预测模型,与基于正交最小二乘法的RBF神经网络进行比较的结果表明:IGA-RBF神经网络设计出来的网络训练步数减少了44步,隐含层节点数减少了34个,且预测模型得到的温湿度误差较小,拟合精度大于0.95,具有更高的预测精度。  相似文献   

6.
针对禽畜养殖场环境废气体积分数数据的处理,使用多个传感器测量环境温度、湿度、某种废气的体积分数。对于传感器故障而失真的数据,使用基于RBF神经网络的数据融合方法融合对某一废气测量值的多种影响因素,估算出该废气的体积分数,从而实现失真数据的恢复。以NH3体积分数数据的处理为例,Matlab仿真结果估算误差小于6.7%,证明了基于RBF网络的数据融合方法的有效性。  相似文献   

7.
在红外CO2传感器的测量过程中,环境总压是一个重要的影响因素。在环境总压变化的情况下做好压力补偿得出正确的CO2气体分压值,对提高传感器的测量精度有重要意义。提出一种基于聚类和梯度法的径向基函数(RBF)神经网络方法,利用它的局部逼近特性,建立起其在红外CO2传感器的非线性压力补偿中的网络模型。实验结果表明:该应用收到了良好的效果。  相似文献   

8.
Sung-Kwun  Seok-Beom  Witold  Tae-Chon   《Neurocomputing》2007,70(16-18):2783
In this study, we introduce and investigate a new topology of fuzzy-neural networks—fuzzy polynomial neural networks (FPNN) that is based on a genetically optimized multiplayer perceptron with fuzzy set-based polynomial neurons (FSPNs). We also develop a comprehensive design methodology involving mechanisms of genetic optimization and information granulation. In the sequel, the genetically optimized FPNN (gFPNN) is formed with the use of fuzzy set-based polynomial neurons (FSPNs) composed of fuzzy set-based rules through the process of information granulation. This granulation is realized with the aid of the C-means clustering (C-Means). The design procedure applied in the construction of each layer of an FPNN deals with its structural optimization involving the selection of the most suitable nodes (or FSPNs) with specific local characteristics (such as the number of input variable, the order of the polynomial, the number of membership functions, and a collection of specific subset of input variables) and address main aspects of parametric optimization. Along this line, two general optimization mechanisms are explored. The structural optimization is realized via genetic algorithms (GAs) and HCM method whereas in case of the parametric optimization we proceed with a standard least square estimation (learning). Through the consecutive process of structural and parametric optimization, a flexible neural network is generated in a dynamic fashion. The performance of the designed networks is quantified through experimentation where we use two modeling benchmarks already commonly utilized within the area of fuzzy or neurofuzzy modeling.  相似文献   

9.
基于QPSO-RBF NN的混沌时间序列预测   总被引:3,自引:0,他引:3  
提出一种基于量子粒子群优化算法训练径向基函数神经网络进行混沌时间序列预测的新方法.在确定径向基函数网络的隐层节点数后,将相应网络的参数,包括隐层基函数中心、扩展常数,以及输出权值和偏移编码成学习算法中的粒子个体,在全局空间中搜索具有最优适应值的参数向量.实例仿真证实了该方法的有效性.  相似文献   

10.
In this paper, a novel particle swarm optimization model for radial basis function neural networks (RBFNN) using hybrid algorithms to solve classification problems is proposed. In the model, linearly decreased inertia weight of each particle (ALPSO) can be automatically calculated according to fitness value. The proposed ALPSO algorithm was compared with various well-known PSO algorithms on benchmark test functions with and without rotation. Besides, a modified fisher ratio class separability measure (MFRCSM) was used to select the initial hidden centers of radial basis function neural networks, and then orthogonal least square algorithm (OLSA) combined with the proposed ALPSO was employed to further optimize the structure of the RBFNN including the weights and controlling parameters. The proposed optimization model integrating MFRCSM, OLSA and ALPSO (MOA-RBFNN) is validated by testing various benchmark classification problems. The experimental results show that the proposed optimization method outperforms the conventional methods and approaches proposed in recent literature.  相似文献   

11.
We introduce a new architecture of information granulation-based and genetically optimized Hybrid Self-Organizing Fuzzy Polynomial Neural Networks (HSOFPNN). Such networks are based on genetically optimized multi-layer perceptrons. We develop their comprehensive design methodology involving mechanisms of genetic optimization and information granulation. The architecture of the resulting HSOFPNN combines fuzzy polynomial neurons (FPNs) that are located at the first layer of the network with polynomial neurons (PNs) forming the remaining layers of the network. The augmented version of the HSOFPNN, “IG_gHSOFPNN”, for brief, embraces the concept of information granulation and subsequently exhibits higher level of flexibility and leads to simpler architectures and rapid convergence speed to optimal structure in comparison with the HSOFPNNs and SOFPNNs.

The GA-based design procedure being applied at each layer of HSOFPNN leads to the selection of preferred nodes of the network (FPNs or PNs) whose local characteristics (such as the number of input variables, the order of the polynomial, a collection of the specific subset of input variables, the number of membership functions for each input variable, and the type of membership function) can be easily adjusted. In the sequel, two general optimization mechanisms are explored. The structural optimization is realized via GAs whereas the ensuing detailed parametric optimization is afterwards carried out in the setting of a standard least square method-based learning. The obtained results demonstrate a superiority of the proposed networks over the existing fuzzy and neural models.  相似文献   


12.
提出一种基于径向基函数(RBF)神经网络的动力系统Lyapunov指数计算方法,设计了一个RBF网络结构,推导了基于RBF网络的Lyapunov指数计算公式.仿真实验表明,与其它现有方法相比,此方法计算精度较高,收敛速度较快,而且只需要较少的样本数据量.本方法能更准确、更快速地计算动力系统的Lyapunov指数.  相似文献   

13.
基于RBF的传感器在线故障诊断和信号恢复   总被引:4,自引:0,他引:4  
介绍利用径向基神经网络构造了一种在线故障诊断及信号恢复方法,给出了网络的连接结构和学习算法。采用RBF神经网络进行传感器在线故障诊断和信号恢复,其仿真结果表明,该方法具有收敛速度快、信号恢复准确度高、泛化能力强的特点,且可以诊断多种复杂工作系统的传感器在线故障信号,同时进行信号的恢复。实现传感器状态监测、故障诊断、分离和信号恢复。  相似文献   

14.
基于快速回归算法的RBF神经网络及其应用   总被引:1,自引:0,他引:1  
针对径向基神经网络(RBFNN)中存在的径向基函数中心的数F1及其位置难以确定的问题,提出了一种新型的基于快速回归算法(FRA)的RBFNN.采用快速回归算法,不但能够确定RBF的中心和中心个数,而且能够求出隐含层到输出层的权重.通过一元函数拟合和Mackey-Glass混沌时间序列预测的仿真,验证了该网络的有效性与实用性.  相似文献   

15.
Developing a precise dynamic model is a critical step in the design and analysis of the overhead crane system. To achieve this objective, we present a novel radial basis function neural network (RBF-NN) modeling method. One challenge for the RBF-NN modeling method is how to determine the RBF-NN parameters reasonably. Although gradient method is widely used to optimize the parameters, it may converge slowly and may not achieve the optimal purpose. Therefore, we propose the cuckoo search algorithm with membrane communication mechanism (mCS) to optimize RBF-NN parameters. In mCS, the membrane communication mechanism is employed to maintain the population diversity and a chaotic local search strategy is adopted to improve the search accuracy. The performance of mCS is confirmed with some benchmark functions. And the analyses on the effect of the communication set size are carried out. Then the mCS is applied to optimize the RBF-NN models for modeling the overhead crane system. The experimental results demonstrate the efficiency and effectiveness of mCS through comparing with that of the standard cuckoo search algorithm (CS) and the gradient method.  相似文献   

16.
In this paper, we introduce an advanced architecture of K-means clustering-based polynomial Radial Basis Function Neural Networks (p-RBF NNs) designed with the aid of Particle Swarm Optimization (PSO) and Differential Evolution (DE) and develop a comprehensive design methodology supporting their construction. The architecture of the p-RBF NNs comes as a result of a synergistic usage of the evolutionary optimization-driven hybrid tools. The connections (weights) of the proposed p-RBF NNs being of a certain functional character and are realized by considering four types of polynomials. In order to design the optimized p-RBF NNs, a prototype (center value) of each receptive field is determined by running the K-means clustering algorithm and then a prototype and a spread of the corresponding receptive field are further optimized through running Particle Swarm Optimization (PSO) and Differential Evolution (DE). The Weighted Least Square Estimation (WLSE) is used to estimate the coefficients of the polynomials (which serve as functional connections of the network). The performance of the proposed model and the comparative analysis involving models designed with the aid of PSO and DE are presented in case of a nonlinear function and two Machine Learning (ML) datasets  相似文献   

17.
浮选生产过程经济技术指标的软测量建模   总被引:1,自引:0,他引:1  
张勇  王介生  王伟  姚伟南 《控制工程》2005,12(4):346-348,378
依据浮选过程的工艺机理和操作经验,初选了浮选过程经济技术指标神经网络软测量模型的输入变量,运用主元分析法对输入变量进行主元分解,降低输入变量维数且消除了输入变量之间的线性相关性,再通过基于最近邻聚类学习算法的径向基函数神经网络进行建模。仿真结果表明,该模型具有较快的训练速率和较高的预测精度,可以满足浮选过程实时控制的在线软测量要求。  相似文献   

18.
In this work, the multiplayer perceptron (MLP) and radial basis function (RBF) neural networks in their simplest forms are employed in function approximation for highly nonlinear and complex analysis and synthesis of the most commonly used planar RF/microwave transmission lines, that is, microstrip lines, coupled microstrip lines, and basic and shielded coplanar‐waveguides. Since the analysis and synthesis processes for these systems have “one‐to‐one mapping” relations with each other, a forward model is defined for the analysis process for all these types of the planar transmission lines; on the other hand, a reverse model is also considered for the synthesis of the same lines. This reverse model is realized by swapping some of the inputs/outputs in the analysis model, and training the neural networks accordingly. Both MLP and RBF types of neural models are applied to the four widely used anisotropic and isotropic dielectric materials: PTFE/microstrip glass, RT/Duroid 6006, alumina and gallium arsenide. The results are shown to agree very well with the targets. A low‐pass filter with 30‐dB attenuation frequency at 3.5 GHz on an alumina substrate is designed by the use of a neural‐network synthesis and its resulting performance agrees well with the one using analytical formulas for the synthesis. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005.  相似文献   

19.
针对风能转换系统执行器部分失效故障,提出了一种新型的主动容错控制策略.应用径向基函数(radial basis function,RBF)自适应神经网络,根据系统状态观测值对执行器故障进行在线重构,基于该重构故障,设计滑模容错控制器切换增益,实现风能转换系统故障诊断与容错控制律在线整定,并进行稳定性证明.仿真结果表明,执行器发生故障时系统的功率系数和叶尖速比均能保持在最优值,从而实现额定风速以下的最大风能捕获.  相似文献   

20.
将径向基神经网络用于Pb~(2 )和Cd~(2 )示波计时电位重叠切口的解析,建立了同时测定Pb~(2 )和Cd~(2 )的径向基神经网络示波计时电位分析新方法。实验表明:所建模型对训练集20个样本,预测结果相对标准偏差平均值仅为0.93%,而主成分回归模型预测结果为3.2%,偏最小二乘回归模型预测结果为3.0%。用本文方法预测的结果比主成分回归和偏最小二乘回归模型准确度高。  相似文献   

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