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1.
本文采用集中性和多样性策略对禁忌搜索进行改进,提出了一种基于模糊神经网络的混合禁忌搜索优化算法(FNN-based Hybrid Tabu Search Algorithm,FNN-HTS),用于同时优化模糊神经网络的结构和参数以提取出一组尽量精练的模糊规则。在FNN-HTS中,禁忌搜索用于同时优化网络结构和隶属函数参数,结合最小二乘法快速求解规则后件的线性参数。非线性函数逼近的实验结果表明所提出的方法能获得一组更精练的规则和更小的误差。  相似文献   

2.
针对滚动轴承故障分类准确率低的问题,提出一种利用遗传算法结合粒子群算法优化支持向量机分类器的故障诊断方法。实验通过提取滚动轴承不同故障状态下的振动信号,以转化成时域和频域组成的特征集为特征向量,利用粒子群生成二维粒子,即惩罚因子C、核函数参数G,并喂入支持向量机进行训练和交叉验证,取最优适应度对应的粒子,进而构建遗传粒子群改进支持向量机故障分类模型。实验证明,粒子群改进的支持向量机与遗传算法改进的支持向量机相比,该算法模型在滚动轴承故障分类中对时域、频域、时频域3个特征集的正确率均有明显改进。  相似文献   

3.
提出一种同时考虑解释性和精确性的模糊建模方法. 首先分析影响模糊模型解释性的主要因素, 然后利用启发式搜索策略实现输入变量选择, 利用模糊聚类算法和最小二乘辨识模糊模型. 随后以输入变量数目和模糊规则数目的乘积衡量可解释性, 以均方误差衡量精确性, 并据此定义模型选择目标函数. 最后给定最大最小的输入变量数目和规则数目, 辨识得到一组模糊模型, 利用模型选择目标函数, 选择最优的模糊模型, 并采用遗传算法进行优化, 达到解释性与精确性的折衷. 煤气炉仿真例子验证了该方法的有效性.  相似文献   

4.
y Control Based on Genetic Algorithm and Its ApplicationsTX1IntroductionMembershipfunctionisthebasisforfuzzylogictheorytoappli...  相似文献   

5.
A novel model of fuzzy clustering using kernel methods is proposed. This model is called kernel modified possibilisticc-means (KMPCM) model. The proposed model is an extension of the modified possibilistic c-means (MPCM) algorithm byusing kernel methods. Different from MPCM and fuzzy c-means (FCM) model which are based on Euclidean distance, theproposed model is based on kernel-induced distance. Furthermore, with kernel methods the input data can be mappedimplicitly into a high-dimensional feature space where the nonlinear pattern now appears linear. It is unnecessary to docalculation in the high-dimensional feature space because the kernel function can do it. Numerical experiments show thatKMPCM outperforms FCM and MPCM.  相似文献   

6.
基于模糊支持向量机的语音情感识别   总被引:1,自引:0,他引:1  
根据输入样本对分类结果不同的影响程度,引入模糊隶属度,探讨了模糊支持向量机(FSVM)原理,并将其应用于汉语语音信号中生气、高兴、悲伤、惊奇4种主要情感类型的识别。仿真实验结果表明FSVM比支持向量机(SVM)有着更好的分类性能和更高的识别率。  相似文献   

7.
In order to improve the output efficiency of a photovoltaic (PV) energy system, the real-time maximum power point (MPP) of the PV array should be tracked closely. The non-linear and time-variant characteristics of the photovoltaic array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP as in traditional control strategies. A neural fuzzy controller (NFC) in conjunction with the reasoning capability of fuzzy logical systems and the learning capability of neural networks is proposed to track the MPP in this paper. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the NFC. With a derived learning algorithm, the parameters of the NFC are updated adaptively. Experimental results show that, compared with the fuzzy logic control algorithm, the proposed control algorithm provides much better tracking performance.  相似文献   

8.
本文提出了一种新的用于复杂系统建模的模糊模型,并从理论上分析证明,该模型可表示任何一个紧集上的连续函数。最后通过一个复杂非线性系统的仿真,验证了本文方法的有效性。  相似文献   

9.
In order to solve three kinds of fuzzy programm model, fuzzy chance-constrained programming mode ng models, i.e. fuzzy expected value and fuzzy dependent-chance programming model, a simultaneous perturbation stochastic approximation algorithm is proposed by integrating neural network with fuzzy simulation. At first, fuzzy simulation is used to generate a set of input-output data. Then a neural network is trained according to the set. Finally, the trained neural network is embedded in simultaneous perturbation stochastic approximation algorithm. Simultaneous perturbation stochastic approximation algorithm is used to search the optimal solution. Two numerical examples are presented to illustrate the effectiveness of the proposed algorithm.  相似文献   

10.
针对时变信号小样本集建模分类问题,提出一种深层多尺度径向基过程神经网络(DLMS-RBFPNN)。该模型由时变信号输入层、多尺度径向基核变换层、全连接层和感知机分类器构成。兼顾时变信号的频谱特征和分布形态的多样性,基于径向基过程神经网络,通过将不同宽度参数的Gauss核函数进行线性叠加,构成多尺度核,完成不同尺度上对过程信号形态特征的提取、辨识和相似性度量。通过在径向基核函数层之上叠加全连接层和分类器,实现时变信号不同尺度特征的融合和分类。DLMS-RBFPNN具有较少的模型参数,适用于小样本集建模,在机制上可提高对时变信号过程细节特征和趋势特征的辨识及记忆能力。在分析DLMS-RBFPNN性质的基础上,建立一种基于动态聚类算法的核中心函数确定方法以及基于PSO的模型参数优化求解算法。以旋转机械基于示功图信号的故障诊断为例进行实验,结果验证了模型和算法的有效性。  相似文献   

11.
提出一种模糊控制规则可自适应调整的控制算法.该算法利用模糊逻辑系统构建模糊辨识器和模糊控制器,依据辨识器在线预估输出误差与模糊控制规则相关参数优化之间的内在联系及自适应优化模糊控制规则.仿真实验表明了该算法的有效性.  相似文献   

12.
研究了基于模糊Lyapunov函数分析连续仿射模糊系统稳定性的方法.首先,对模糊系统局部模型的后件部分进行扩展处理,以便于借鉴齐次模糊模型的稳定性分析方法.然后,分别得到基于改进公共Lyapunov函数与模糊Lyapunov函数的系统稳定条件,该条件可表示为一组线性矩阵不等式.通过算例对所得稳定条件进行对比,结果表明:...  相似文献   

13.
1Introduction Moltencarbonatefuelcell(MCFC)isaclearelec tricitygeneratingtechniquewithhighefficiency,which istobeusedwidely.Withoutcombustion,MCFCcon vertschemicalenergycontainedinfuelandoxidantin toelectricenergyviaelectro chemicalreaction.Per formanceof…  相似文献   

14.
Feature extraction from vibration signals has been investigated extensively over the past decades as a key issue in machine condition monitoring and fault diagnosis. Most existing methods, however, assume a linear model of the underlying dynamics. In this study, the feasibility of devoting nonlinear dynamic parameters to characterizing bearing vibrations is studied. Firstly, fuzzy sample entropy (FSampEn) is formulated by defining a fuzzy membership function with clear physical meaning. Secondly, inspired by the multiscale sample entropy (multiscale SampEn) which is originally proposed to quantify the complexity of physiological time series, we placed approximate entropy (ApEn), fuzzy approximate entropy (FApEn) and the proposed FSampEn into the same multiscale framework. This led to the developments of multiscale ApEn, multiscale FApEn and multiscale FSampEn. Finally, all four multiscale entropies along with their single-scale counterparts were employed to extract discriminating features from bearing vibration signals, and their classification performance was evaluated using support vector machines (SVMs) Experimental results demonstrated that all four multiscale entropies outperformed single-scale ones, whilst multiscale FSampEn was superior to other multiscale methods, especially when analyzed signals were contaminated by heavy noise. Comparisons with statistical features in time domain also support the use ofmultiscale FSampEn.  相似文献   

15.
A single machine scheduling problem involving fuzzy due dates and fuzzy precedence constraints is investigated. The fuzzy precedence reflects the satisfaction level with respect to precedence between two jobs. A membership function is associated with each job Ji, which describes the degree of satisfaction with respect to completion time of Ji. For the bi-criteria scheduling problem, an 0 ( n^3 ) algorithm is proposed for finding nondominated solutions.  相似文献   

16.
在传统故障诊断基础上,将多Agent技术(MAS)应用于复杂系统故障诊断领域,是求解复杂过程故障诊断问题的一种新尝试.研究了基于MAS的分布式智能故障诊断模型,基于一种分布式Agent诊断系统结构原型系统,重点研究了诊断问题的任务辨识、分解问题,构建了基于Agent的任务分配的综合遗传算法和模拟退火算法的混合算法.应用表明,该算法具有很好的可扩展性、适应性和稳定性.  相似文献   

17.
一种新的模糊边缘检测算法   总被引:5,自引:0,他引:5  
基于信息论中最大熵原理 ,提出了一种新的模糊边缘检测算法 .首先介绍了模糊概率、用条件概率与条件熵定义模糊划分熵的概念以及模糊划分的原理 .算法利用了自然划分以及梯度图像模糊划分的关系 ,在条件概率与模糊划分熵的基础上 ,通过最大模糊熵原则实现图像分割中最优阈值的自动提取 ,从而实现图像的边缘检测 .对不同测试图像的边缘检测结果进行比较 ,表明了该算法的有效性 .  相似文献   

18.
提出了一种TS型模糊PID控制器的改进算法。通过对两种TS型模糊PID控制器进行分析,指出存在的问题并提出改进方法,引入非线性量化因子,优化隶属函数,引入积分环节,降低模糊控制器的维数,简化规则等,使改进后的模糊PID控制器在规则少、参数简化、参数调解难度降低的基础上获得更好的控制效果。  相似文献   

19.
对BP型ANN网络用于模拟电路故障诊断的特点进行了介绍,探讨了利用遗传算法确定BP型ANN网络参数的方法,并给出了遗传算法与BP型ANN相结合实现模拟电路故障诊断的应用.实践表明,该方法的诊断精度、诊断速度以及建立诊断模型的自动化程度都有了较大的提高.  相似文献   

20.
为了在缺少设计参数的条件下,设计一个非线性模型的热电联产故障诊断系统,提出了一种基于模糊神经网络的设计方法。通过分析热电联产控制系统各工作模块的工作过程,建立废热回收蒸汽锅炉、蒸汽集箱、汽吸收式冷凝器等模块工作模型。并采用粒子群优化算法对提出的模糊神经网络进行优化,假设模型和测量误差正常分布且相互独立,对模型置信区间进行了计算。实验测试表明,本文设计的故障检测具有较高的可信度。  相似文献   

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