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1.
一种模糊逻辑推理神经网络的结构及算法设计   总被引:11,自引:0,他引:11  
建立了一种基于模糊逻辑推理的神经网络.由样本获取的初始规则确定规则层神经元个数,并确立模糊化层与规则层之间的连接.利用黄金分割法确定模糊化层隶属度函数的初始中心和宽度;根据初始规则的结论确定清晰化层的初始权值;针对网络结构提出了改进的BP算法.仿真实例表明,网络结构合理。具有较好的非线性映射能力,改进的BP算法适合于此网络,与另一种模糊神经网络相比较具有较快的训练速度和较好的泛化能力.  相似文献   

2.
多层前馈模糊神经网络进行图像识别   总被引:1,自引:0,他引:1  
神经网络和模糊技术在模式识别领域中已有了广泛应用,两者有着各自的优势。针对神经网络模式识别中所遇到的问题,为了进一步提高分类器在样本分布不清晰情况下的识别能力,本文提出了两各将模糊机制引入神经网络的方法-输入模糊化方法和隐层模糊化方法,并在此基础上分别构造了模糊神经网络。实验结果表明,模糊神经网络较好地结合了神经网络和模糊技术的优点,取得了比传统网络更好的识别结果。  相似文献   

3.
针对烧结过程这一复杂、多参数耦合的高度非线性系统,融合遗传算法、神经网络和模糊控制的优点,提出一种基于改进遗传算法的模糊神经网络控制方法,并应用于烧结过程终点控制.首先采用遗传算法对给定的模糊神经网络控制器结构参数进行离线优化,然后利用BP算法较强的局部搜索能力和对对象的适应能力,进一步进行参数的在线调整.同时,为解决传统遗传算法早熟和收敛速度慢的问题,从交叉和变异算子、适应度函数选取等方面对遗传算法进行改进.采用精英保留策略,提高了全局搜索性能和收敛速度.仿真结果表明,所提出的控制器优于常规的模糊神经网络控制器(Fuzzy Neural Network Controller, FNNC).算法的实际应用效果良好,为解决烧结终点控制问题提供了一条新的途径.  相似文献   

4.
Recurrent neuro-fuzzy networks for nonlinear process modeling   总被引:14,自引:0,他引:14  
A type of recurrent neuro-fuzzy network is proposed in this paper to build long-term prediction models for nonlinear processes. The process operation is partitioned into several fuzzy operating regions. Within each region, a local linear model is used to model the process. The global model output is obtained through the centre of gravity defuzzification which is essentially the interpolation of local model outputs. This modeling strategy utilizes both process knowledge and process input/output data. Process knowledge is used to initially divide the process operation into several fuzzy operating regions and to set up the initial fuzzification layer weights. Process I/O data are used to train the network. Network weights are such trained so that the long-term prediction errors are minimized. Through training, membership functions of fuzzy operating regions are refined and local models are learnt. Based on the recurrent neuro-fuzzy network model, a novel type of nonlinear model-based long range predictive controller can be developed and it consists of several local linear model-based predictive controllers. Local controllers are constructed based on the corresponding local linear models and their outputs are combined to form a global control action by using their membership functions. This control strategy has the advantage that control actions can be calculated analytically avoiding the time consuming nonlinear programming procedures required in conventional nonlinear model-based predictive control. The techniques have been successfully applied to the modeling and control of a neutralization process.  相似文献   

5.
A neural fuzzy system with linguistic teaching signals   总被引:2,自引:0,他引:2  
A neural fuzzy system learning with linguistic teaching signals is proposed. This system is able to process and learn numerical information as well as linguistic information. It can be used either as an adaptive fuzzy expert system or as an adaptive fuzzy controller. First, we propose a five-layered neural network for the connectionist realization of a fuzzy inference system. The connectionist structure can house fuzzy logic rules and membership functions for fuzzy inference. We use α-level sets of fuzzy numbers to represent linguistic information. The inputs, outputs, and weights of the proposed network can be fuzzy numbers of any shape. Furthermore, they can be hybrid of fuzzy numbers and numerical numbers through the use of fuzzy singletons. Based on interval arithmetics, two kinds of learning schemes are developed for the proposed system: fuzzy supervised learning and fuzzy reinforcement learning. Simulation results are presented to illustrate the performance and applicability of the proposed system  相似文献   

6.
We discuss the direct fuzzification of a standard layered, feedforward, neural network where the signals and weights are fuzzy sets. A fuzzified delta rule is presented for learning. Three applications are given including fuzzy expert systems, fuzzy hierarchical analysis, and fuzzy systems modeling. © 1993 John Wiley & Sons, Inc.  相似文献   

7.
一种基于Vague集相似度量推理的控制器设计   总被引:3,自引:0,他引:3  
关学忠  赵肖宇  关勇  佟亮 《控制工程》2006,13(1):15-17,24
针对模糊变量隶属值难以确定、描述信息单一这一问题,将区间值模糊集引入控制领域。在Vague集相似度量推理基础上,设计了一种模糊控制器。为了应用Vague集相似度量推理方法,给出了一种清晰量的区间值模糊化方法。说明了该类模糊控制器设计过程,给出Matlab仿真控制效果。仿真结果表明,该控制器隶属函数值较易确定,设计过程简化,模糊化过程偏差小,有很好的应用价值。  相似文献   

8.
The Hybrid neural Fuzzy Inference System (HyFIS) is a multilayer adaptive neural fuzzy system for building and optimizing fuzzy models using neural networks. In this paper, the fuzzy Yager inference scheme, which is able to emulate the human deductive reasoning logic, is integrated into the HyFIS model to provide it with a firm and intuitive logical reasoning and decision-making framework. In addition, a self-organizing gaussian Discrete Incremental Clustering (gDIC) technique is implemented in the network to automatically form fuzzy sets in the fuzzification phase. This clustering technique is no longer limited by the need to have prior knowledge about the number of clusters present in each input and output dimensions. The proposed self-organizing Yager based Hybrid neural Fuzzy Inference System (SoHyFIS-Yager) introduces the learning power of neural networks to fuzzy logic systems, while providing linguistic explanations of the fuzzy logic systems to the connectionist networks. Extensive simulations were conducted using the proposed model and its performance demonstrates its superiority as an effective neuro-fuzzy modeling technique.  相似文献   

9.
In this study, an on-line tuning method is proposed for fuzzy PID controllers via rule weighing. The rule weighing mechanism is a fuzzy rule base with two inputs namely; “error” and “normalized acceleration”. Here, the normalized acceleration provides relative information on the fastness or slowness of the system response. In deriving the fuzzy rules of the weighing mechanism, the transient phase of the unit step response of the closed loop system is to be analyzed. For this purpose, this response is assumed to be divided into certain regions, depending on the number of membership functions defined for the error input of the fuzzy logic controller. Then, the relative importance or influence of the fired fuzzy rules is determined for each region of the transient phase of the unit step response of the closed loop system. The output of the fuzzy rule weighing mechanism is charged as the tuning variable of the rule weights; and, in this manner, an on-line self-tuning rule weight assignment is accomplished. The effectiveness of the proposed on-line weight adjustment method is demonstrated on linear and non-linear systems by simulations. Moreover, a real time application of this new method is accomplished on a pH neutralization process.  相似文献   

10.
本文针对参数固定的模糊控制系统难以适应控制过程中的工况的变化的弊端,提出一种基于神经网络的模糊控制系统(NFC),引入3层BP网络在线修正模糊控制器的参数,使得控制系统具有更好的动态特性和静态性能。  相似文献   

11.
A hierarchical network of neural network planning and control is employed to successfully accomplish a task such as grasping in a cluttered real world environment. In order for the individual robot joint controllers to follow their specific reference commands, information is shared with other neural network controllers and planners within the hierarchy. Each joint controller is initialized with weights that will acceptably control given a change in any of several crucial parameters across a broad operating range. When increased accuracy is needed as parameters drift, the diagnostic node fuzzy supervisor interprets the controller network's diagnostic outputs and transitions the weights to a closest fit specificchild controller. Future reference commands are in turn influenced by the diagnostic outputs of every robot joint neural network controller. The neural network controller and diagnostics are demonstrated for linear and nonlinear plants.  相似文献   

12.
This paper proposes an intelligent task planning and action selection mechanism for a mobile robot in a robot soccer system through a fuzzy neural network approach. The proposed fuzzy neural network system is developed through the two dimensional fuzzification of the soccer field. A five layer fuzzy neural network system is trained through error back propagation learning algorithm to impart a strategy based action selection. The action selection depends on the field configuration, and the emergence of a particular field configuration results from the game dynamics. Strategy of the robot changes when the configuration of the objects in the field changes. The proposed fuzzy neural network structure is flexible to accommodate all possible filed configurations. Simulation results indicate that the proposed approach is simple and has the capability in coordinating the multi-agent system through selection of sensible actions.  相似文献   

13.
In many systems, such as fuzzy neural network, we often adopt the language labels (such as large, medium, small, etc.) to split the original feature into several fuzzy features. In order to reduce the computation complexity of the system after the fuzzification of features, the optimal fuzzy feature subset should be selected. In this paper, we propose a new heuristic algorithm, where the criterion is based on min–max learning rule and fuzzy extension matrix is designed as the search strategy. The algorithm is proved in theory and has shown its high performance over several real-world benchmark data sets.  相似文献   

14.
深度神经模糊系统算法及其回归应用   总被引:1,自引:0,他引:1  
深度神经网络是人工智能的热点, 可以很好处理高维大数据, 却有可解释性差的不足. 通过IF-THEN规则构建的模糊系统, 具有可解释性强的优点, 但在处理高维大数据时会遇到“维数灾难”问题. 本文提出一种基于ANFIS (Adaptive network based fuzzy inference system)的深度神经模糊系统(Deep neural fuzzy system, DNFS)及两种基于分块和分层的启发式实现算法: DNFS1和DNFS2. 通过四个面向回归应用的数据集的测试, 我们发现: 1)采用分块、分层学习的DNFS在准确度与可解释性上优于BP、RBF、GRNN等传统浅层神经网络算法, 也优于LSTM和DBN等深度神经网络算法; 2)在低维问题中, DNFS1具有一定优势; 3)在面对高维问题时, DNFS2表现更为突出. 本文的研究结果表明DNFS是一种新型深度学习方法, 不仅可解释性好, 而且能有效解决处理高维数据时模糊规则数目爆炸的问题, 具有很好的发展前景.  相似文献   

15.
针对油田开发指标预测问题,提出一种模糊神经网络模型,该模型包括输入层、模糊化层、规则层和输出层。模糊化层采用高斯隶属函数,规则层每个节点对应一条模糊逻辑规则。网络可调参数为模糊集参数和输出层权值。提出了基于改进量子粒子群优化的网络训练方法。以油田开发指标中含水率预测为例,结果表明该方法是有效的可行的。  相似文献   

16.
The paper considers the neuro-fuzzy position control of multi-finger robot hand in tele-operation system—an active master–slave hand system (MSHS) for demining. Recently, fuzzy control systems utilizing artificial intelligent techniques are also being actively investigated in robotic area. Neural network with their powerful learning capability are being sought as the basis for many adaptive control systems where on-line adaptation can be implemented. Fuzzy logic on the other hand has been proved to be rather popular in many control system applications providing a rule-base like structure. In this paper, the design and optimization process of fuzzy position controller is supported by learning techniques derived from neural network where a radial basis function (RBF) neural network is implemented to learn fuzzy rules and membership functions with predictor of recurrent neural network (RNN) model. The results of experiment show that based on the predictive capability of RNN model neuro-fuzzy controller with good adaptation and robustness capability can be designed.  相似文献   

17.
In this paper, an adaptive backstepping control problem is proposed for a class of multiple-input-multiple-output nonlinear non-affine uncertain systems. An output recurrent wavelet neural network (ORWNN) is used to approximate the unknown nonlinear functions to develop the proposed adaptive backstepping controller. The proposed ORWNN combines the advantages of wavelet-based neural network, fuzzy neural network, and output feedback layer to achieve higher approximation accuracy and faster convergence. According to the estimation of ORWNN, the control scheme is designed by backstepping approach such that the system outputs follow the desired trajectories. Based on the Lyapunov approach, our approach guarantees that the system outputs converge to a small neighborhood of the references signals, that is, all signals of the closed-loop system are semi-globally uniformly ultimately bounded. Finally, simulation results including double pendulums system and two inverted pendulums on carts system are shown to demonstrate the performance and effectiveness of our approach.  相似文献   

18.
针对pH值控制过程具有较强非线性、纯滞后性的特点,传统PID控制往往达不到满意控制效果。介绍一种将模糊控制技术与神经网络技术相结合构成的模糊神经网络pH控制器,通过数字仿真显示了该控制算法的控制效果优于传统的PID控制和一般的模糊控制算法。并将提出的模糊神经网络控制算法在DSP上进行了实现.通过模拟实验验证了该控制器的可行性。  相似文献   

19.
基于RBF辨识的模糊神经网络控制器的设计与实现   总被引:3,自引:0,他引:3  
随着众多新型模糊神经网络被提出,针对模糊神经网络具有的典型特点,即需要对输入输出数据范围进行转化和处理,所涉及到的对量化因子和比例因子的实时调节问题,该文提出一种优化方案。其依据神经网络具有的自学习能力,通过增加模糊神经网络的层数,提出一种包含对量化因子和比例因子调节的改进型模糊神经网络,以减少系统的辅助优化环节。同时,引入辨识性能较好的径向基函数神经网络(RBF)为系统提供精确的Jacobian信息,取代常规的近似做法。最后结合实例仿真证明了该优化方案的合理性。  相似文献   

20.
基于模糊神经网络的模型参考自适应控制   总被引:11,自引:0,他引:11  
张乃尧  栾天 《自动化学报》1996,22(4):476-480
用模糊神经网络作为控制器,依靠参考模型产生理想的控制系统闭环响应,从而随时得 到控制系统的输出误差.用梯度法实时修正模糊控制器的输入和输出隶属度参数,得到一种 在线模糊自适应控制的新方法.通过倒立摆的仿真实验表明,该方法是可行的并能适应对象 特性的大范围变化.  相似文献   

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