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1.
基于自适应模糊网络的在线辨识   总被引:4,自引:4,他引:0  
喻英  阮学斌 《控制工程》2005,12(5):426-428,435
研究了基于一阶Sugeno的自适应网络模糊推理系统(ANFIS)进行在线辨识的方法。给出了该自适应网络的结构,在此基础上给出了网络权值的修正算法,即综合最陡下降法和最小二乘法得到的一种混合学习算法。对一个非线性模型进行了数字仿真,得到的在线辨识的结果优于采用反传算法的普通神经网络辨识方法。由此证明,一阶Sugeno模糊推理模型和混合学习算法的采用,使得该辨识方法具备网络结构简单、收敛速度快的优势,便于工程实现。  相似文献   

2.
为提高异构有向传感器网络的节点调度效率,基于学习自动机提出一种参数自适应的差分进化算法。将节点调度问题转化为集合覆盖问题,利用学习自动机与环境的交互实现差分算法控制参数的自适应选择,同时采用自适应的变异策略增强算法解决集合覆盖问题时的寻优能力。仿真结果表明,相比原始差分进化算法,该算法拓展了参数自适应性,优化能力更强,并且能够延长异构有向传感器网络的生存时间。  相似文献   

3.
王林  彭璐  夏德  曾奕 《计算机工程与科学》2015,37(12):2270-2275
针对BP神经网络学习算法随机初始化连接权值和阈值易使模型陷入局部极小点的缺点,设计了一种自适应差分进化算法优化BP神经网络的混合算法。该混合算法中,差分进化算法采用自适应变异和交叉因子优化BP神经网络的初始权值和阈值,再用预寻优得到的初始权值和阈值训练BP神经网络得到最优的权值和阈值。首先对改进的自适应差分进化算法运用测试函数进行性能测试,然后用一个经典时间序列问题对提出的混合算法进行了检验,并与一般的神经网络、ARIMA预测模型及其它混合预测模型进行了对比,实验结果表明,本文提出的混合算法有效并且明显提高了预测精度。  相似文献   

4.
《微型机与应用》2016,(4):88-90
利用最小二乘法将超声回波参数估计问题转化为优化问题,采用改进的差分进化算法(DE算法)对待优化函数进行优化处理。仿真研究说明,该方法在噪声环境下依然有效,并且不依赖于初始值选择,不需计算梯度,可以在全局范围内搜索。  相似文献   

5.
差分进化算法是一类基于种群的启发式全局搜索技术,但传统的差分进化算法存在停滞现象,容易使算法收敛停止。虽然之后出现了各种版本的自适应差分进化算法,但没有考虑到当代个体的适应值是否向着最优个体的适应值逼近,因此本文提出了一种新型的自适应差分进化算法FMDE。考虑到粒子群算法和差分进化算法类似,为了充分发挥两种算法的特点,提出了自适应差分进化和粒子群的混合算法PSO_FMDE;最后采用测试数据集对性能进行分析。实验结果表明,该算法根据进化过程中的搜索进度自适应地确定变异率,使算法易于跳出局部最优解,以提高全局搜索能力。PSO_FMDE算法较单一算法而言,性能更优,更易于靠近全局最优解。  相似文献   

6.
该文针对相机标定过程中因优化算法所引起的精度不足、稳定性差、易陷入局部最优的问题,提出将樽海鞘优化算法和自适应差分进化算法相结合的相机标定优化算法。该混合算法利用樽海鞘优化算法提高精度,利用自适应差分进化算法增强局部搜索能力,在不同迭代阶段对适应度函数采用分段优化方式,实现平衡局部和全局搜索能力。实验采用每格50 mm×50 mm标准的棋盘格作为标定板,选取15张不同角度的标定图片,图片有效像素为4608 pixe×l3456 pixel,分别利用张正友标定法、樽海鞘算法以及本文提出的樽海鞘-自适应差分进化混合算法进行相机内参的优化。实验结果表明该文提出的混合算法比传统标定方法重投影误差更小,标定精度更高。  相似文献   

7.
贝叶斯网络的结构学习是贝叶斯网络理论模型的核心,而现有的贝叶斯网络结构学习算法一般存在效率偏低的问题.针对此问题,文中提出基于混合差分蜂群算法的贝叶斯网络结构学习算法.该算法首先利用最大生成树准则得到初始种群,然后利用差分进化算法中的交叉、变异规则优化初始种群.在使用差分进化算法的过程中,分别将蜂群算法应用于变异阶段和优化改进交叉阶段,并且将云自适应理论应用于选择阶段选择生成个体.在经典贝叶斯网络上的仿真实验证明,文中算法在贝叶斯网络结构学习中具有较强的寻优能力.  相似文献   

8.
提出一种基于小生境自适应差分进化小波神经网络(NADE-WNN)的方法对不确定混沌系统进行控制。该方法利用小波神经网络学习未知模型混沌系统的动态特性并实施控制,为提高神经网络的学习精度和收敛速度,采用小生境自适应差分进化算法同时优化小波神经网络的结构和参数,简化网络结构,提高网络的学习精度和全局收敛性。仿真实验结果表明,在有外部干扰和参数摄动的情况下,NADE-WNN仍能对不确定混沌系统进行有效控制,且网络结构、控制精度和收敛速度都优于传统神经网络。  相似文献   

9.
Hammerstein系统是一类典型的块结构非线性系统,由非线性静态子系统和线性动态子系统构成,由于模型中含有未知非线性变量,传统辨识算法往往存在辨识精度不高、辨识效果差等问题。因此,基于启发式的智能优化算法受到了关注。差分进化(Differential Evolution, DE)算法是一种模拟自然界生物种群“适者生存”原则的智能算法,待定参数少,收敛速度快,但会陷入局部最优。针对这一局限性,提出一种改进差分进化算法来辨识Hammerstein受控自回归滑动平均模型。在基本差分进化算法的基础上改变了变异操作和交叉操作,加入自适应因子。推导了递推最小二乘算法来辨识Hammerstein系统,并将其与改进的差分进化算法进行比较。通过仿真例子测试算法性能,结果表明,相对于递推最小二乘算法、基本DE算法和粒子群算法,改进差分进化算法在精确度和收敛速度上更优。将改进DE算法用于连续搅拌反应釜的辨识,取得了较好的辨识效果。  相似文献   

10.
基于ANFIS的机器人系统建模的研究   总被引:1,自引:0,他引:1  
针对机器人这种不确定性的复杂非线性系统很难建立其精确的数学模型这一问题,提出一种基于自适应神经模糊推理(ANFIS)的方法对机器人系统进行建模.此方法将模糊推理和神经网络的学习能力有机地结合起来,并利用神经网络的学习机制自动地从输入输出数据中提取规则.建模过程中为了给ANFIS赋予一个合适的初始状态,选用减法聚类对输入数据进行处理.ANFIS网络的所有参数采用混合算法进行调节,即前提参数采用误差反向传播法,结论参数采用最小二乘法.最后在Matlab中对二自由度机器人进行仿真研究,仿真结果表明该方法模型结构简单,建模速度快,辨识精度高,同时也验证了该方法的有效性,为进一步实现机器人鲁棒自适应控制打下基础.  相似文献   

11.
为了进一步提高模糊系统建立模型的精度,提出一种新的模糊系统算法ANFIS-HC-QPSO:采用一种混合型模糊聚类算法来对模糊系统的输入空间进行划分,每一个聚类通过高斯函数的拟合产生一个隶属度函数,即完成ANFIS系统的前件参数--隶属度函数参数的初始识别,通过具有量子行为的粒子群算法QPSO与最小二乘法优化前件参数,直至达到停机条件,最终得到ANFIS的前件及后件参数,从而得到满意的模糊系统模型。实验表明,AN-FIS-HC-QPSO算法与传统算法相比,能在只需较少模糊规则的前提下就使模糊系统达到更高的精度。  相似文献   

12.
This paper proposes a novel hybrid learning algorithm with stable learning laws for Adaptive Network based Fuzzy Inference System (ANFIS) as a system identifier and studies the stability of this algorithm. The new hybrid learning algorithm is based on particle swarm optimization (PSO) for training the antecedent part and forgetting factor recursive least square (FFRLS) for training the conclusion part. Two famous training algorithms for ANFIS are the gradient descent (GD) to update antecedent part parameters and using GD or recursive least square (RLS) to update conclusion part parameters. Lyapunov stability theory is used to study the stability of the proposed algorithms. This paper, also studies the stability of PSO as an optimizer in training the identifier. Stable learning algorithms for the antecedent and consequent parts of fuzzy rules are proposed. Some constraints are obtained and simulation results are given to validate the results. It is shown that instability will not occur for the leaning rate and PSO factors in the presence of constraints. The learning rate can be calculated on-line and will provide an adaptive learning rate for the ANFIS structure. This new learning scheme employs adaptive learning rate that is determined by input–output data. Also, stable learning algorithms for two common methods are proposed based on Lyapunov stability theory and some constraints are obtained.  相似文献   

13.
城市短时交通流预测可以帮助人们选择出行最优路线,提高出行效率,其研究在交通拥堵日益严重的今天十分必要.受天气等多种因素影响,短时交通流的精确预测比较困难,为改善短时交通流预测的精度,本文提出了一种基于自适应模糊推理系统(ANFIS)的混合模型.该混合模型用周期性知识模型及残差数据驱动ANFIS模型集成得到.为验证所提出的混合模型的性能,与倒向传播神经网络(BPNN)模型和普通ANFIS模型进行对比.实验结果证明混合模型在交通流预测方面有更好的适用性和准确度.  相似文献   

14.
An important issue in application of fuzzy inference systems (FISs) to a class of system identification problems such as prediction of wave parameters is to extract the structure and type of fuzzy if–then rules from an available input–output data set. In this paper, a hybrid genetic algorithm–adaptive network-based FIS (GA–ANFIS) model has been developed in which both clustering and rule base parameters are simultaneously optimized using GAs and artificial neural nets (ANNs). The parameters of a subtractive clustering method, by which the number and structure of fuzzy rules are controlled, are optimized by GAs within which ANFIS is called for tuning the parameters of rule base generated by GAs. The model has been applied in the prediction of wave parameters, i.e. wave significant height and peak spectral period, in a duration-limited condition in Lake Michigan. The data set of year 2001 has been used as training set and that of year 2004 as testing data. The results obtained by the proposed model are presented and analyzed. Results indicate that GA–ANFIS model is superior to ANFIS and Shore Protection Manual (SPM) methods in terms of their prediction accuracy.  相似文献   

15.
In this paper, speed control of Brushless DC motor using Bat algorithm optimized online Adaptive Neuro-Fuzzy Inference System is presented. Learning parameters of the online ANFIS controller, i.e., Learning Rate (η), Forgetting Factor (λ) and Steepest Descent Momentum Constant (α) are optimized for different operating conditions of Brushless DC motor using Genetic Algorithm, Particle Swarm Optimization, and Bat algorithm. In addition, tuning of the gains of the Proportional Integral Derivative (PID), Fuzzy PID, and Adaptive Fuzzy Logic Controller is optimized using Genetic Algorithm, Particle Swarm Optimization and Bat Algorithm. Time domain specification of the speed response such as rise time, peak overshoot, undershoot, recovery time, settling time and steady state error is obtained and compared for the considered controllers. Also, performance indices such as Root Mean Squared Error, Integral of Absolute Error, Integral of Time Multiplied Absolute Error and Integral of Squared Error are evaluated and compared for the above controllers. In order to validate the effectiveness of the proposed controller, simulation is performed under constant load condition, varying load condition and varying set speed conditions of the Brushless DC motor. The real time experimental verification of the proposed controller is verified using an advanced DSP processor. The simulation and experimental results confirm that bat algorithm optimized online ANFIS controller outperforms the other controllers under all considered operating conditions.  相似文献   

16.
提出了一种基于减法聚类-自适应模糊神经网络(ANFIS)的网络故障诊断建模方法。减法聚类算法生成初始模糊推理系统,ANFIS建立网络故障诊断原始模型,应用混合算法对模糊规则的参数进行训练并建立最终的模型。仿真实验表明基于减法聚类-ANFIS的建模方法是有效的;通过仿真结果比较,减法聚类-ANFIS的网络故障诊断能力及收敛速度均优于BP神经网络,更适合作为网络故障诊断模型。  相似文献   

17.
In this article, a wavelet neural network (WNN) model is proposed for approximating arbitrary nonlinear functions. Our WNN model structure comes from the idea of adaptive neuro-fuzzy inference system (ANFIS) which is used for obtaining fuzzy rule base from the input–output data of an unknown function. The WNN model which is called in this study as adaptive wavelet network (AWN) consists of wavelet scaling functions in its processing units whereas in an ANFIS, mostly Gaussian-type membership functions are used for a function approximation. We present to train an AWN by a hybrid-learning method containing least square estimation (LSE) with gradient-based optimization algorithm to obtain the optimal translation and dilation parameters of our AWN for model accuracy. Simulation examples are also given to illustrate the effectiveness of the method.  相似文献   

18.
本文针对小波网络现有学习算法的不足,把Levenberg-Marquardt算法(简称LM算法)和最小二乘算法有机地结合在一起,提出了一种新的小波网络混合学习算法.在该混合算法中LM算法用来训练小波网络的非线性参数,而最小二乘算法用来训练线性参数.最后以辩识一个混沌系统为例进行了数值仿真,并与改进的BP算法和单纯LM算法进行了比较,结果说明了所提算法具有很好的收敛性能和收敛速度.  相似文献   

19.
Multiple Kernel Learning with Adaptive Neuro-Fuzzy Inference System (MKL with ANFIS) based deep learning method is proposed in this paper for heart disease diagnosis. The proposed MKL with ANFIS based deep learning method follows two-fold approach. MKL method is used to divide parameters between heart disease patients and normal individuals. The result obtained from the MKL method is given to the ANFIS classifier to classify the heart disease and healthy patients. Sensitivity, Specificity and Mean Square Error (MSE) are calculated to evaluate the proposed MKL with ANFIS method. The proposed MKL with ANFIS is also compared with various existing deep learning methods such as Least Square with Support Vector Machine (LS with SVM), General Discriminant Analysis and Least Square Support Vector Machine (GDA with LS-SVM), Principal Component Analysis with Adaptive Neuro-Fuzzy Inference System (PCA with ANFIS) and Latent Dirichlet Allocation with Adaptive Neuro-Fuzzy Inference System (LDA with ANFIS). The results from the proposed MKL with ANFIS method has produced high sensitivity (98%), high specificity (99%) and less Mean Square Error (0.01) for the for the KEGG Metabolic Reaction Network dataset.  相似文献   

20.
提出一种基于改进遗传算法和递推最小二乘的非线性模糊辨识新算法.该辨识方法包含结构辨识辨出和参数辨识,结构辨识即输入空间的模糊划分,采用具有自适应性的广义高斯隶属函数;参数辨识包含前提参数和结论参数,用基于动态比例变换的改进遗传算法优化高斯函数的前提参数,用递推最小二乘辨识模糊模型的结论参数.最后通过著名的Box-Jenkins煤气炉数据仿真(仿真环境:MATLAB 6.5,计算机主频2.4 GHz,内存512 MB),并根据输入变量个数和模糊规则数,得到均方误差以证明本文方法的辨识精度,将该文辨识方法与其他方法进行比较,验证了该方法辨识精度更高.  相似文献   

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