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1.
郭凯路 《计算机仿真》2020,(2):377-380,389
采用当前方法识别特定虚拟图像中存在的局部多变特征时,识别多变特征所用的时间较长,得到的识别结果与实际不符,存在识别效率低和识别准确率低的问题。提出特定虚拟图像局部多变特征识别方法,在不改变原有样本协方差结构的基础上,采用PCA降维算法调整类间离散矩阵和类内离散矩阵,最大化类间聚类、最小化类内距离,去除特定虚拟图像中存在的无用数据和冗余信息。融合非局域全变分和结构张量构建图像去噪模型,利用图像去噪模型去除特定虚拟图像中存在的噪声。对预处理后的特定虚拟图像进行Contourlet变换,在不同方向、不同尺度上提取特定虚拟图像的变换系数,构建语言变量,通过模糊逻辑方法计算模糊区域在模糊特征空间中对应的激活强度值,获得特定虚拟图像局部多变特征向量,将特征向量输入支持向量机分类器中,实现特定虚拟图像局部多变特征的识别。仿真结果表明,所提方法的识别效率高、识别准确率高。  相似文献   

2.
Fuzzy classification has become of great interest because of its ability to utilize simple linguistically interpretable rules and has overcome the limitations of symbolic or crisp rule based classifiers. This paper introduces an extension to fuzzy classifier: a neutrosophic classifier, which would utilize neutrosophic logic for its working. Neutrosophic logic is a generalized logic that is capable of effectively handling indeterminacy, stochasticity acquisition errors that fuzzy logic cannot handle. The proposed neutrosophic classifier employs neutrosophic logic for its working and is an extension of commonly used fuzzy classifier. It is compared with the commonly used fuzzy classifiers on the following parameters: nature of membership functions, number of rules and indeterminacy in the results generated. It is proved in the paper that extended fuzzy classifier: neutrosophic classifier; optimizes the said parameters in comparison to the fuzzy counterpart. Finally the paper is concluded with justifying that neutrosophic logic though in its nascent stage still holds the potential to be experimented for further exploration in different domains.  相似文献   

3.
Handwriting recognition requires tools and techniques that recognize complex character patterns and represent imprecise, common-sense knowledge about the general appearance of characters, words and phrases. Neural networks and fuzzy logic are complementary tools for solving such problems. Neural networks, which are highly nonlinear and highly interconnected for processing imprecise information, can finely approximate complicated decision boundaries. Fuzzy set methods can represent degrees of truth or belonging. Fuzzy logic encodes imprecise knowledge and naturally maintains multiple hypotheses that result from the uncertainty and vagueness inherent in real problems. By combining the complementary strengths of neural and fuzzy approaches into a hybrid system, we can attain an increased recognition capability for solving handwriting recognition problems. This article describes the application of neural and fuzzy methods to three problems: recognition of handwritten words; recognition of numeric fields; and location of handwritten street numbers in address images  相似文献   

4.
介绍了一种基于动态聚类的模糊分类规则的生成方法,这种方法能决定规则数目,隶属函数的位置及形状.首先,介绍了基于超圆雏体隶属函数的模糊分类规则的基本形式;然后,介绍动态聚类算法,该算法能将每一类训练模式动态的分为成簇,对于每簇,则建立一个模糊规则;通过调整隶属函数的斜度,来提高对训练模式分类识别率,达到对模糊分类规则进行优化调整的目的;用两个典型的数据集评测了这篇文章研究的方法,这种方法构成的分类系统在识别率与多层神经网络分类器相当,但训练时间远少于多层神经网络分类器的训练时间.  相似文献   

5.
This paper describes an intelligent computerized tool designed to aid managers of software development projects in planning, managing and controlling the development process of medium- to large-scale software projects. Systems dynamics is used to model and simulate the dynamic process of software development. The software development process is affected by some imprecise and vague variables that are treated as fuzzy variables. The simulation model is integrated with two expert systems. The fuzzy input variables to the system dynamics simulation model are handled by an input expert system having fuzzy logic. This expert system is designed to check the consistency of input variables. The simulation results are analysed by an output expert system having fuzzy logic. This expert system is designed to make recommendations based on experimentation with the simulation model.  相似文献   

6.
To facilitate full-loaded commandos to control reconnaissance robots, in this paper, we propose a wearable hand posture control system based on egocentric-vision by imitating the sign language interaction way among commandos. Considering the characteristics of the egocentric-vision on the battlefield, such as complicated backgrounds, large ego-motions and extreme transitions in lighting, a new hand detector based on Binary Edge HOG Block (BEHB) features is proposed to extract articulated postures from the egocentric-vision. Different from many other methods that use skin color cues, our proposed hand detector adopts contour cues and part-based voting idea. This means that our algorithm can be used on the battlefield even in dark environment, because infrared cameras can be used to get contour images rather than skin color images. The experiment result shows that the proposed hand detector can get a better posture detection result on the NUS hand posture dataset II. To improve hand recognition accuracy, a deep ensemble hybrid classifier is proposed by combing hybrid CNN-SVM classifier and ensemble technique. Compared with other state-of-art algorithms, the proposed classifier yields a recognition accuracy of 97.72 % on the NUS hand posture dataset II. At last, to reduce misjudgments during consecutive posture switches, a vote filter is proposed and applied to the sequence of the recognition results. The scout experiment shows that our wearable hand posture control system is more suitable than traditional hand-held controllers for full-loaded commandos to control reconnaissance robots.  相似文献   

7.
针对训练模式类标签不精确的识别问题,提出基于可传递信度模型的自适应模糊k-NN(k-Nearest Neighbor)分类器。利用可传递信度模型结合模糊集理论和可能性理论并运用pignistic变换,对待识别模式真正所属的类做出决策。采用梯度下降最小化误差函数,以实现参数的自适应学习。实验结果表明,该分类器误分类率低、鲁棒性强。  相似文献   

8.
Support vector learning for fuzzy rule-based classification systems   总被引:11,自引:0,他引:11  
To design a fuzzy rule-based classification system (fuzzy classifier) with good generalization ability in a high dimensional feature space has been an active research topic for a long time. As a powerful machine learning approach for pattern recognition problems, the support vector machine (SVM) is known to have good generalization ability. More importantly, an SVM can work very well on a high- (or even infinite) dimensional feature space. This paper investigates the connection between fuzzy classifiers and kernel machines, establishes a link between fuzzy rules and kernels, and proposes a learning algorithm for fuzzy classifiers. We first show that a fuzzy classifier implicitly defines a translation invariant kernel under the assumption that all membership functions associated with the same input variable are generated from location transformation of a reference function. Fuzzy inference on the IF-part of a fuzzy rule can be viewed as evaluating the kernel function. The kernel function is then proven to be a Mercer kernel if the reference functions meet a certain spectral requirement. The corresponding fuzzy classifier is named positive definite fuzzy classifier (PDFC). A PDFC can be built from the given training samples based on a support vector learning approach with the IF-part fuzzy rules given by the support vectors. Since the learning process minimizes an upper bound on the expected risk (expected prediction error) instead of the empirical risk (training error), the resulting PDFC usually has good generalization. Moreover, because of the sparsity properties of the SVMs, the number of fuzzy rules is irrelevant to the dimension of input space. In this sense, we avoid the "curse of dimensionality." Finally, PDFCs with different reference functions are constructed using the support vector learning approach. The performance of the PDFCs is illustrated by extensive experimental results. Comparisons with other methods are also provided.  相似文献   

9.
基于BP神经网络的人脸识别方法   总被引:26,自引:1,他引:25  
人脸自动识别是计算机模式识别领域的一个活跃课题,有着十分广泛的应用前景。文中提出了基于BP神经网络的人脸识别方法,论述了人脸图像矢量的特征压缩问题、网络隐含层神经元数选取问题、网络输入矢量的标准化处理问题以及网络连接权值选取问题。对于18人、每人12幅图像组成的脸图像数据库做识别实验,实验结果表明文中所设计的神经网络分类器比常用的最近邻分类器有效地降低了识别错误率。  相似文献   

10.
虚拟维修仿真中手势识别的研究与应用   总被引:1,自引:0,他引:1  
孙培  苏群星  刘鹏远 《计算机仿真》2009,26(6):277-280,303
虚拟维修训练仿真要求良好的逼真性和沉浸感,对训练操作者的动作意图能高效地转化.将手势识别技术应用于虚拟维修仿真作为的获取可以有效满足这种要求.通过装备维修动作的建模研究分析定义了能够体现动作意图的必需手势;之后采用模糊神经网络技术实现对手势的识别并建立基于手势识别的虚拟手交互控制机制.还重点对神经网络的构建以及学习算法进行了介绍,并在现有适用度计算方法的基础上结合网络实际提出了适用度的平均求解法.最后将基于手势识别的虚拟手交互控制方法应用于具体维修训练仿真中并证明了方法的可行性和高效性.  相似文献   

11.
We present an approach for MPEG variable bit rate (VBR) video modeling and classification using fuzzy techniques. We demonstrate that a type-2 fuzzy membership function, i.e., a Gaussian MF with uncertain variance, is most appropriate to model the log-value of I/P/B frame sizes in MPEG VBR video. The fuzzy c-means (FCM) method is used to obtain the mean and standard deviation (std) of T/P/B frame sizes when the frame category is unknown. We propose to use type-2 fuzzy logic classifiers (FLCs) to classify video traffic using compressed data. Five fuzzy classifiers and a Bayesian classifier are designed for video traffic classification, and the fuzzy classifiers are compared against the Bayesian classifier. Simulation results show that a type-2 fuzzy classifier in which the input is modeled as a type-2 fuzzy set and antecedent membership functions are modeled as type-2 fuzzy sets performs the best of the five classifiers when the testing video product is not included in the training products and a steepest descent algorithm is used to tune its parameters  相似文献   

12.
Uncertainty of data, fuzzy membership functions, and multilayer perceptrons   总被引:1,自引:0,他引:1  
Probability that a crisp logical rule applied to imprecise input data is true may be computed using fuzzy membership function (MF). All reasonable assumptions about input uncertainty distributions lead to MFs of sigmoidal shape. Convolution of several inputs with uniform uncertainty leads to bell-shaped Gaussian-like uncertainty functions. Relations between input uncertainties and fuzzy rules are systematically explored and several new types of MFs discovered. Multilayered perceptron (MLP) networks are shown to be a particular implementation of hierarchical sets of fuzzy threshold logic rules based on sigmoidal MFs. They are equivalent to crisp logical networks applied to input data with uncertainty. Leaving fuzziness on the input side makes the networks or the rule systems easier to understand. Practical applications of these ideas are presented for analysis of questionnaire data and gene expression data.  相似文献   

13.
模糊积分理论可有效处理分类决策不确定性问题。当前模糊密度的确定方法未考虑各个分类器识别结果的可区分程度及各分类器对识别结果的支持程度,会丢失融合识别的相关信息。文中提出基于可分度和支持度的自适应模糊密度赋值融合识别算法。该算法根据各分类器对待识别样本的识别结果的可区分程度和支持程度对分类器的融合模糊密度进行自适应赋值,从而有效实现多分类器融合识别。将该算法应用于自然交互环境下的人脸表情识别和Cohn-Kanade表情识别。实验结果表明,该算法能有效提高总体表情识别率。  相似文献   

14.
鉴于常规单点模糊逻辑系统在解决不确定性问题中存在的不足,该文在分析非单点模糊逻辑理论的基础之上,提出了一种新的自适应非单点模糊辨识器,并且详细论述了其相关理论、具体实现步骤和参数优化方法。针对一种糖酵解混沌振荡器模型的非线性动态系统辨识问题,采用非单点模糊逻辑系统对其进行了仿真研究,取得了较好的逼进和收敛效果,从而验证了该非单点模糊辨识器的可行性和有效性。该研究结果表明了基于非单点模糊逻辑系统构造的自适应辨识器能够在一定精度和时间区域内跟踪非线性动态系统的输出,并且非单点模糊理论将能够在控制等其它应用领域取得较好的应用效果。  相似文献   

15.
In this paper, we present a fuzzy logic modulation classifier that works in nonideal environments in which it is difficult or impossible to use precise probabilistic methods. We first transform a general pattern classification problem into one of function approximation, so that fuzzy logic systems (FLS) can be used to construct a classifier; then, we introduce the concepts of fuzzy modulation type and fuzzy decision and develop a nonsingleton fuzzy logic classifier (NSFLC) by using an additive FLS as a core building block. Our NSFLC uses 2D fuzzy sets, whose membership functions are isotropic so that they are well suited for a modulation classifier (MC). We establish that our NSFLC, although completely based on heuristics, reduces to the maximum-likelihood modulation classifier (ML MC) in ideal conditions, In our application of NSFLC to MC in a mixture of α-stable and Gaussian noises, we demonstrate that our NSFLC performs consistently better than the ML MC and it gives the same performance as the ML MC when no impulsive noise is present  相似文献   

16.
针对传统人脸识别方法在单样本条件下识别效果不佳的问题,提出一种改进的对光照和表情姿态等变化具有较强鲁棒性的梯度脸算法——正交梯度二值模式(OGBP)。首先采用正交梯度二值模式对样本图像进行特征提取,然后将每个方向特征向量串接起来作为用于人脸识别的总体特征向量,最后通过主成分分析(PCA)方法降维并利用最近邻分类器分类识别。在YALE和AR人脸库上进行测试,实验结果表明所提方法简单有效,性能优于原始的梯度脸算法,且对单样本人脸描述具有更好的效果。  相似文献   

17.
This paper develops a fuzzy logic based position controller whose membership functions are tuned by genetic algorithm. The main goal is to ensure successful velocity and position trajectories tracking between the mobile robot and the virtual reference cart. The proposed fuzzy controller has two inputs and two outputs. The first input represents the distance between the mobile robot and the reference cart. The second input is the angle formed by the straight line defined with the orientation of the robot, and the straight line that connects the robot with the reference cart. The outputs represent linear and angular velocity commands, respectively. The performance of the fuzzy controller is validated through comparison with previously developed mobile robot position controller based on control Lyapunov functions (CLF). Simulation results indicate good performance of position tracking while at the same time a substantial reduction of the control torques is achieved.  相似文献   

18.
This study presents an innovative fuzzy estimator that efficiently and robustly estimates the vibratory forces of a beam–machine system. The proposed estimator includes fuzzy Kalman filter technology, which is accelerated by the fuzzy accelerating factor and the fuzzy weighting recursive least-square method, weighted by the fuzzy weighting factor based on the fuzzy logic inference system. The excellent performance of this estimator is demonstrated by comparing it with different weighting functions, distinct levels of noise covariance measurement and the initial process noise covariance. The simulation results show that the proposed method is efficient in estimating input vibration forces, giving this method great stability and precision.  相似文献   

19.
Noise classification is very important nowadays. Fuzzy logic has been applied to many interesting problems in different areas including noise identification/recognition. With this study, we propose an automatic environmental noise source classifier based on fuzzy logic. The proposed classifier uses the feature parameters that are extracted using short-time auto-correlation function. Six commonly encountered non-stationary noise sources are chosen to recognize. These are subway, airport, inside car, inside train, restaurant, and rain. Classification accuracy of the proposed classifier ranged from 62% to 90% rates.  相似文献   

20.
In this paper, we discuss a fuzzy classifier with ellipsoidal regions that dynamically generates clusters. First, for the data belonging to a class we define a fuzzy rule with an ellipsoidal region. Namely, using the training data for each class, we calculate the center and the covariance matrix of the ellipsoidal region for the class. Then we tune the fuzzy rules, i.e., the slopes of the membership functions, successively until there is no improvement in the recognition rate of the training data. Then if the number of the data belonging to a class that are misclassified into another class exceeds a prescribed number, we define a new cluster to which those data belong and the associated fuzzy rule. Then we tune the newly defined fuzzy rules in the similar way as stated above, fixing the already obtained fuzzy rules. We iterate generation of clusters and tuning of the newly generated fuzzy rules until the number of the data belonging to a class that are misclassified into another class does not exceed the prescribed number. We evaluate our method using thyroid data, Japanese Hiragana data of vehicle license plates, and blood cell data. By dynamic cluster generation, the generalization ability of the classifier is improved and the recognition rate of the fuzzy classifier for the test data is the best among the neural network classifiers and other fuzzy classifiers if there are no discrete input variables  相似文献   

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