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1.
韩红桂  林征来  乔俊飞 《控制与决策》2017,32(12):2169-2175
为了实现模糊神经网络结构和参数的同时调整,提出一种基于无迹卡尔曼滤波(UKF)的增长型模糊神经网络(UKF-GFNN).首先,利用UKF对模糊神经网络的参数进行调整;然后,设计一种基于隐含层神经元输出强度的模糊规则增长机制,实现模糊神经网络的结构增长;最后,将所提出的增长型模糊神经网络应用于非线性系统建模.实验结果显示,基于UKF的增长型模糊神经网络能够实现结构和参数的自校正,并且具有较高的建模精度.  相似文献   

2.
文章介绍了一种基于进化式模糊神经网络时间预测系统,它是一种快速自适应的局部学习模型;进化式模糊神经网络是一个特殊类型的神经网络,它能通过进化其结构和参数来容纳新的数据.文章重点介绍了网络结构、学习方法及创建、修剪、聚合规则节点的算法;实验结果表明:模糊隶属函数的个数,规则的修剪和聚合等训练参数,与网络的行为和预测结果有很重要的关系.  相似文献   

3.

针对模糊神经网络结构设计问题及模糊集在语言描述上存在的不足, 提出一种基于扩展的卡尔曼滤波(EKF)的自组织T-S 模糊Elman 网络, 并推导了网络训练算法. 分别采用递归最小二乘法和EKF 对线性参数和非线性参数进行更新; 基于模糊规则生成准则和误差下降率修剪策略实现了模糊规则的增删减. 最后通过系统辨识和污水处理建模实验, 表明了该算法在保证网络精度和泛化能力的同时, 可以有效地简化网络结构.

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4.
文章介绍了一种基于进化式模糊神经网络时间预测系统,它是一种快速自适应的局部学习模型;进化式模糊神经网络是一个特殊类型的神经网络,它能通过进化其结构和参数来容纳新的数据。文章重点介绍了网络结构、学习方法及创建、修剪、聚合规则节点的算法;实验结果表明:模糊隶属函数的个数,规则的修剪和聚合等训练参数,与网络的行为和预测结果有很重要的关系。  相似文献   

5.
针对复杂不确定非线性系统的辨识问题,提出一种基于聚类的自组织区间二型模糊神经网络学习算法.首先采用具有两个不同加权参数的FCM算法对输入数据进行划分来获取规则前件的不确定均值,同时结合聚类有效性标准确定模糊规则数目,从而自动完成神经网络的结构辨识和规则前件参数辨识;随后给出了基于梯度下降法和Lyapunov函数稳定收敛定理的规则后件权向量学习速率的自适应学习算法.通过非线性系统辨识实例,验证了该算法与其他方法相比具有更快的收敛速度和更高的逼近精度;并且利用该算法建立了某市电力短期负荷预测模型,结果表明该模型具有较高的预测精度,泛化性能更佳.  相似文献   

6.
一种用模糊—神经技术建造专家系统的方法   总被引:4,自引:0,他引:4  
本文提出了一种用模糊-神经技术建造专家系统的方法。从领域专家处获取的知识是以模糊规则和隶属函数的形式表示的。根据本文提出的方法,首先将模糊规则和隶属函数用神经网络表示出来(导入);生成的神经网络用于实现模糊推理,然后利用修改的反传算法训练神经网络,从而提高系统的精度,修改隶属函数,求精模糊规则;最后从神经网络中提取隶属函数和模糊规则(导入),帮助解释神经网络的内部表示和操作,利用本文所提出的方法建  相似文献   

7.
针对量测噪声方差统计值未知的非线性UKF(Unscented Kalman Filter)滤波问题,提出了一种基于梯度自适应规则的自适应UKF算法;在标准的非线性UKF算法基础上,根据残差方差阵的估计值与真实值之差构造代价指标函数,并将该函数相对于参数变化的负梯度方向作为参数更新的方向,构建自适应调节机制;将算法应用于GPS/DR(Dead-Reckoning)组合导航系统中,仿真结果显示状态估计误差具有良好的收敛性,估计精度较噪声观测器有明显改善,表明算法对量测噪声方差阵的动态变化具有较强的适应性。  相似文献   

8.
神经模糊控制在船舶自动舵中的应用   总被引:4,自引:0,他引:4  
针对常规模糊自动舵由于受船舶控制过程的非线性、时变性以及风浪干扰等因素影响,模糊控制规则和隶属函数需要校正,利用神经网络的自学习能力,用神经网络去实现模糊控制,设计自动舵神经模糊控制器,采用BP算法和最小二乘算法的混合学习算法实现对模糊规则和隶属函数的参数训练,提高控制器的自适应能力。仿真实验表明所设计的控制器有效可行,适应船舶在风浪干扰环境下的控制性能要求。  相似文献   

9.
神经模糊控制在船舶自动舵中的应用   总被引:1,自引:0,他引:1  
针对常规模糊自动舵由于受船舶控制过程的非线性、时变性以及风浪干扰等因素影响,模糊控制规则和隶属函数需要校正,利用神经网络的自学习能力,用神经网络去实现模糊控制,设计自动舵神经模糊控制器,采用BP算法和最小二乘算法的混合学习算法实现对模糊规则和隶属函数的参数训练,提高控制器的自适应能力.仿真实验表明所设计的控制器有效可行.适应船舶在风浪干扰环境下的控制性能要求.  相似文献   

10.
本文提出了新颖的机器人末端臂轨迹跟踪自适应控制方法。该方法与已有的神经网络模型不同之处在于数据首先利用运动学反解求出机器人各关节旋转的角度,然后应用径向基函数自组织进行神经网络学习生成模糊规则,利用监督学习算法(SLA)、最小二乘法(LMS)、反向传播算法(BP)和聚类分析的方法在线优化控制规则以及隶属函数的参数。仿真结果表明,该方法不但规则生成的时间少,有效的防止了规则数爆炸,而且在机器人轨迹跟踪控制的应用中效果好。  相似文献   

11.
Neural networks, which make no assumption about data distribution, have achieved improved image classification results compared to traditional methods. Unfortunately, a neural network is generally perceived as being a ‘black box’. It is extremely difficult to document how specific classification decisions are reached. Fuzzy systems, on the other hand, have the capability to represent classification decisions explicitly in the form of fuzzy ‘if-then’ rules. However, the construction of a knowledge base, especially the fine-tuning of the fuzzy set parameters of the fuzzy rules in a fuzzy expert system, is a tedious and subjective process. This research has developed a new, improved neuro-fuzzy image classification system based on the synergism between neural networks and fuzzy expert systems. It incorporates the best of both technologies and compensates for the shortcomings of each. The learning algorithms of neural networks developed here are used to automate the derivation of fuzzy set parameters for the fuzzy ‘if-then’ rules in a fuzzy expert system. The rules obtained, in symbolic form, facilitate the understanding of the neural network based image classification system. In addition, the image classification accuracy obtained from the improved neuro-fuzzy system was significantly superior to those of the back-propagation based neural network and the maximum likelihood approaches.  相似文献   

12.
The paper presents results of application of a rule induction and pruning algorithm for classification of a microseismic hazard sate in coal mines. Due to imbalanced distribution of examples describing states “hazardous” and “safe”, the special algorithm was used for induction and rule pruning. The algorithm selects optimal parameters‘ values influencing rule induction and pruning based on training and tuning sets. A rule quality measure which decides about a form and classification abilities of rules that are induced is the basic parameter of the algorithm. The specificity and sensitivity of a classifier were used to evaluate its quality. Conducted tests show that the admitted method of rules induction and classifier’s quality evaluation enables to get better results of classification of microseismic hazards than by methods currently used in mining practice. Results obtained by the rules-based classifier were also compared with results got by a decision tree induction algorithm and by a neuro-fuzzy system.  相似文献   

13.
We present an application of type-2 neuro-fuzzy modeling to stock price prediction based on a given set of training data. Type-2 fuzzy rules can be generated automatically by a self-constructing clustering method and the obtained type-2 fuzzy rules cab be refined by a hybrid learning algorithm. The given training data set is partitioned into clusters through input-similarity and output-similarity tests, and a type-2 TSK rule is derived from each cluster to form a fuzzy rule base. Then the antecedent and consequent parameters associated with the rules are refined by particle swarm optimization and least squares estimation. Experimental results, obtained by running on several datasets taken from TAIEX and NASDAQ, demonstrate the effectiveness of the type-2 neuro-fuzzy modeling approach in stock price prediction.  相似文献   

14.
介绍了一种利用模糊神经元网络实现车辆自动驾驶的设计方案.其基本设计思想 是首先通过模糊逻辑描述驾驶者的驾驶行为,然后利用驾驶者实际驾驶时采集的车辆运行情 况作为训练数据,通过神经元网络的自学习功能修改和改进模糊控制所需的输入/输出信 号的隶属度函数以及模糊推理的运算关系,做到简单控制实现与复杂学习算法的有效结合, 从而实现模糊神经元控制.本方案为智能车辆实现个性化自主或辅助自动驾驶提供了一种非 常有效的机制.  相似文献   

15.
基于模糊加权神经网络的模糊规则自动获取   总被引:3,自引:0,他引:3  
马铭  徐岩  张利彪 《计算机应用》2003,23(11):15-17
如何实现模糊规则的自动获取一直是模糊系统中的一个难题,文中在充分研究了模糊加权神经网络和遗传算法的基础上,给出了一种能够自动获取模糊规则的剪枝算法,并以此建立了新的网络模型。模拟结果验证了该模型的有效性。  相似文献   

16.
Self-organized fuzzy system generation from training examples   总被引:3,自引:0,他引:3  
In the synthesis of a fuzzy system two steps are generally employed: the identification of a structure and the optimization of the parameters defining it. The paper presents a methodology to automatically perform these two steps in conjunction using a three-phase approach to construct a fuzzy system from numerical data. Phase 1 outlines the membership functions and system rules for a specific structure, starting from a very simple initial topology. Phase 2 decides a new and more suitable topology with the information received from the previous step; it determines for which variable the number of fuzzy sets used to discretize the domain must be increased and where these new fuzzy sets should be located. This, in turn, decides in a dynamic way in which part of the input space the number of fuzzy rules should be increased. Phase 3 selects from the different structures obtained to construct a fuzzy system the one providing the best compromise between the accuracy of the approximation and the complexity of the rule set. The accuracy and complexity of the fuzzy system derived by the proposed self-organized fuzzy rule generation procedure (SOFRG) are studied for the problem of function approximation. Simulation results are compared with other methodologies such as artificial neural networks, neuro-fuzzy systems, and genetic algorithms  相似文献   

17.
Neuro-fuzzy rule generation: survey in soft computing framework   总被引:9,自引:0,他引:9  
The present article is a novel attempt in providing an exhaustive survey of neuro-fuzzy rule generation algorithms. Rule generation from artificial neural networks is gaining in popularity in recent times due to its capability of providing some insight to the user about the symbolic knowledge embedded within the network. Fuzzy sets are an aid in providing this information in a more human comprehensible or natural form, and can handle uncertainties at various levels. The neuro-fuzzy approach, symbiotically combining the merits of connectionist and fuzzy approaches, constitutes a key component of soft computing at this stage. To date, there has been no detailed and integrated categorization of the various neuro-fuzzy models used for rule generation. We propose to bring these together under a unified soft computing framework. Moreover, we include both rule extraction and rule refinement in the broader perspective of rule generation. Rules learned and generated for fuzzy reasoning and fuzzy control are also considered from this wider viewpoint. Models are grouped on the basis of their level of neuro-fuzzy synthesis. Use of other soft computing tools like genetic algorithms and rough sets are emphasized. Rule generation from fuzzy knowledge-based networks, which initially encode some crude domain knowledge, are found to result in more refined rules. Finally, real-life application to medical diagnosis is provided.  相似文献   

18.
The authors previously introduced a fuzzy version of Kohonen's well-known self-organizing map neural network model. In this novel neuro-fuzzy system, the neurons of Kohonen's original model are replaced by fuzzy rules. Each fuzzy rule is composed of fuzzy sets and an output singleton. Since the fuzzy self-organizing map is a modified version of Kohonen's original model, the self-organizing map and the learning vector quantization learning laws can be used to tune the neuro-fuzzy system. Originally, the fuzzy self-organizing map was intended to be used as an unknown function approximator, while Kohonen's self-organizing map is primarily used as a neural classifier. In this paper, the authors show how the fuzzy self-organizing map can also be used as a neuro-fuzzy classifier. Simulation results show that, in chemical agent detection, the fuzzy self-organizing map not only gives better classification results than Kohonen's model, but it also has smaller number of fuzzy rules than the corresponding neurons required by Kohonen's self-organizing map  相似文献   

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