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1.
针对当前零水印不能"嵌入"有意义水印的不足,构建了在小波域中基于神经网络的零水印系统,提出了一种基于模糊RBF神经网络的音频零水印方案,有效解决了音频水印的鲁棒性与透明性之间的矛盾.模糊神经网络模糊系统的隶属度函数和推理规则决定RBF神经网络的结构和学习算法.因为水印方案不改变原始音频数据,所以具有良好的透明性,实验结果表明,方案具有很强的鲁棒性.  相似文献   

2.
输入变量个数会对模糊建模精度产生影响.对于一个实际的复杂系统,可测的或者需要考虑的输入变量非常多.是不是考虑的影响因素越多,即模糊系统的输入变量越多,则辨识的效果就越好呢?本文基于T-S模糊模型,分别采用对称三角形模糊划分和网格对角线法以及模糊聚类划分提取模糊规则,对Box-Jenkins煤气炉数据和Mackey-Glass混沌时间序列进行建模,得到了模糊模型训练性能指标和检验性能指标随输入变量个数增加时的变化趋势曲线,并给出了结论.  相似文献   

3.
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   

4.
首先定义了对偶犹豫模糊语言变量,然后给出其运算规则、得分值函数、精确值函数、比较规则以及对偶犹豫模糊语言变量的加权算术平均算子、有序加权算术平均算子和混合平均算子。针对属性值为对偶犹豫模糊语言变量的多属性决策问题,提出了一种基于对偶犹豫模糊语言变量集结算子的多属性决策方法。最后,结合国家电网公司合作单位选择问题,验证了该方法的有效性和可行性。  相似文献   

5.
模糊运算和模糊有限元静力控制方程的求解   总被引:20,自引:0,他引:20  
根据模糊数的区间形式表达和区间运算的性质,给出了模糊数和模糊变量的运算规则.据此并依据区间有限元理论,提出了结构模糊有限元静力控制方程的几种求解方法.方法可根据输入模糊数的隶属函数,给出结构响应量的可能性分布.且计算量小,易于实施.算例分析说明了方法是实用和可行的.  相似文献   

6.
多变量模糊控制器的研究   总被引:9,自引:0,他引:9  
自L.A.Zadeh的《Fuzzy Sets》一文后,模糊系统理论得到了很大发展,一些学者作了许多有益的研究工作.1974年,E.H.Mamdami首先在生产过程使用模糊控制.近十几年来,模糊控制形成了比较一般的语言控制规则及控制算法. 关于多变量的模糊控制的实现非常困难.本文在单变量的基础上,将一个多变量模糊控制器转化成多个单变量模糊控制器的组合,利用补偿的方法,消除多变量模糊系统间的耦合.  相似文献   

7.
基于知识的模糊神经网络的旋转机械故障诊断   总被引:9,自引:0,他引:9  
提出了一种基于知识的模糊神经网络并用于故障诊断.首先基于粗糙集对样本数据进行初步规则获取,并计算规则的依赖度和条件覆盖度,然后根据规则数目进行模糊神经网络结构部分设计,规则的依赖度和条件覆盖度用于设定网络初始权重,而用遗产算法对神经网络输出参数进行优化.这样的模糊神经网络称为基于知识的模糊神经网络.使用该网络对旋转机械常见故障进行诊断,结果表明,和一般模糊神经网络相比,该网络具有训练时间短而诊断率高的特点.  相似文献   

8.
本文针对四足步行机器人模糊控制器规则庞大,逻辑复杂的问题,提出了一种分层模糊控制器的设计方法。该方法不依赖被控对象的数学模型,将状态变量分层以降低多变量系统的设计复杂性,仿真和实验结果显示了该方法的有效性。  相似文献   

9.
基于模糊动态模型 ,研究了 Chua混沌系统的稳定控制问题 .将非线性混沌系统模糊化为局部线性模型 .用 Lyapunov稳定性理论设计出 ,确保模糊动态模型全局渐近稳定的变结构控制器 .仿真验证了方案的有效性 .模糊控制器简单 ,规则少 .  相似文献   

10.
Bernardo方法是一种多属性群决策方法。针对Bernardo方法,本文结合模糊不确定性理论,提出“模糊Bernardo”方法;利用模糊变量表示决策者对多方案排序的模糊目标值,给出其Bernardo方法的模糊混合0-1规划模型和模糊机会约束混合0-1规划模型。该方法为群决策提供了一种多方案排序问题的实用且有效的理论依据和计算方法。最后通过实例对此方法予以验证。  相似文献   

11.
G. Bortolan   《Fuzzy Sets and Systems》1998,100(1-3):197-215
Fuzzy sets have been used successfully in order to deal with imprecise data, linguistic terms or not well-defined concepts. Recently, considerable effort has been made in the direction of combining the neural network approach with fuzzy sets. In this paper a fuzzy feed-forward neural network, able to process trapezoidal fuzzy sets, has been investigated. Normalized trapezoidal fuzzy sets have been considered. The fuzzy generalized delta rule with different back-propagation algorithms is discussed. The more interesting and characteristic property of the proposed architecture is the ability of each node to process fuzzy sets or linguistic terms, preserving the simplicity of the back-propagation algorithm. Consequently, the resulting architecture is able to cope with problems in which the input parameters and the desired targets are described by linguistic terms. This methodology has the further interesting characteristic of being able to operate at the linguistic level rather than at the numerical level, that is it can work at a higher data abstraction level. An example in computerized electrocardiography will be illustrated in order to test the proposed approach.  相似文献   

12.
The inventory policy, meant as a replenishment rule, has a considerable impact on most firms. The paper considers the determination of optimal inventory policy of firms from a global viewpoint of top management. The inventory is represented as a fuzzy system with the fuzzy inventory level as the output, the fuzzy replenishment as the input and fuzzy demand. The control problem is formulated in terms of decision-making in a fuzzy environment with fuzzy constraints imposed on replenishments, a fuzzy goal for preferable inventory levels to be attained and the fuzzy decision as the intersection of fuzzy constraints and the fuzzy goal at subsequent stages. The planning horizon is infinite. The problem is to find an optimal time-invariant strategy relating the optimal replenishments to the current inventory levels, maximizing the membership function of fuzzy decision. The existence of such a strategy is proved and an algorithm for its determination is given. The optimal time-invariant strategy obtained is represented as a fuzzy conditional statement equated with a fuzzy relation which is the firm's optimal fuzzy replenishment rule.  相似文献   

13.
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   

14.
作用模糊子集推理方法的研究与应用   总被引:20,自引:1,他引:19  
针对实用模糊控制过程,提出作用模糊子集和作用模糊控制规则的概念;根据模糊逻辑推理中真值的产生、传递和接收机理,提出作用模糊子集推理方法;比较分析了作用模糊子集推理方法与CRI法的推理结果;利用该推理方法实现了试验室温度模糊控制试验。  相似文献   

15.
In this paper a fuzzy controller is proposed to regulate the intake manifold pressure and the fresh mass airflow of diesel engines simultaneously. The instrumentation set usually embedded in a mass-produced passenger car has been considered. Unlike many multi-variable controllers, the proposed structure requires neither an internal model nor identification algorithms. In comparison to controllers embedded at present in standard engine control units (ECUs), it improves the trajectory tracking of desired outputs during simulation of EURO cycles. Because of its performance, the fuzzy controller has been implemented in an electronics control unit. Some real-time results are presented.  相似文献   

16.
基于神经网络的模糊决策方法   总被引:4,自引:0,他引:4  
给出用神经网络去处理模糊决策问题的方法,此方法避免了模糊决策计算量大、计算复杂,隶属函数确定带有主观性等问题。  相似文献   

17.
本文对具有不确定性控制对象提出了一种自学习模糊神经网络控制方法,模糊控制器采用误差,误差变化及误差加速度的加权和解析描述形式,利用人工神经网络直接对过程的建模,实现对模糊加权因子的自学习优化调整。将上述方法用于焊接熔池动态过程控制实实验,结果表明本文提出的自学习模糊神经网络控制方案有效。  相似文献   

18.
Portfolio selection theory with fuzzy returns has been well developed and widely applied. Within the framework of credibility theory, several fuzzy portfolio selection models have been proposed such as mean–variance model, entropy optimization model, chance constrained programming model and so on. In order to solve these nonlinear optimization models, a hybrid intelligent algorithm is designed by integrating simulated annealing algorithm, neural network and fuzzy simulation techniques, where the neural network is used to approximate the expected value and variance for fuzzy returns and the fuzzy simulation is used to generate the training data for neural network. Since these models are used to be solved by genetic algorithm, some comparisons between the hybrid intelligent algorithm and genetic algorithm are given in terms of numerical examples, which imply that the hybrid intelligent algorithm is robust and more effective. In particular, it reduces the running time significantly for large size problems.  相似文献   

19.
到目前为止,我们所研究的模糊或非模糊的自动机都是有限状态自动机.然而,关于无限状态自动机的定义及它的稳定性和收敛性都没有被讨论过.本文中,我们使用离散的反馈神经网络及网络输出空间划分方法,同时,在梯度更新算法中使用伪梯度方法,给出了模糊无限状态自动机收敛到模糊有限状态自动机的证明.  相似文献   

20.
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   

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