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基于小波包与支持向量机的复杂信号模式识别 总被引:5,自引:0,他引:5
为很好地识别神经和肌肉的功能状态,针对表面肌电信号的非平稳特性,提出了采用小波包变换的方法对原始肌电信号进行分解,并提取其频段系数的最大奇异值构建特征矢量.利用"一对一"的分类策略和二又树构建多类支持向量机分类器,经训练后可以有效地对前臂8种动作的表面肌电信号进行识别,8种动作的平均识别率达到99.375%.实验结果表明,支持向量机分类器的识别率明显优于传统的BP神经网络、Elman神经网络和RBF神经网络分类器,且鲁棒性好,并具有良好的泛化推广能力. 相似文献
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为了有效提取表面肌电信号SEMG(Surface Electromyographic)的特征,更好的识别人体上肢运动模式,提出了一种小波包核主元分析(WPKPCA)和支持向量机(SVM)相结合的新方法。通过虚拟仪器采集桡侧腕屈肌和肱桡肌两路表面肌电信号,应用小波包核主元分析法对表面肌电信号进行特征提取,采用支持向量机对表面肌电信号特征数据进行分类识别。实验结果表明,采用此方法能够从表面肌电信号中识别出握拳、展拳、手腕内翻和手腕外翻4种动作,更能有效提取表面肌电信号信息,动作识别率高达98%。 相似文献
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表面肌电信号识别特征提取的仿真研究 总被引:1,自引:0,他引:1
研究表面肌电信号准确识别问题,表面肌电信号含有大量的噪声,且特征维数高,传统方法无法消除其中的噪声,选择最重要识别特征信号,表面肌电信号识别正确率低.为提高表面肌电信号的识别正确率,提出一种新的表面肌电信号识别模型.首先采用小波变换提取表面肌电信号特征,消除信号中的噪声,然后采用遗传算法选择最优特征信号,降低特征维数,最后采用遗传算法对支持向量机参数进行优化建立最优表面肌电信号识别模型.仿真结果表明,模型可很好地解决传统方法中的难题,提高了表面肌电信号的平均识别正确率,识别结果非常稳定,为表面肌电信号提供了一种新的识别方法. 相似文献
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《模式识别与人工智能》2014,(6)
针对人体表面肌电信号的非平稳、非线性特点,提出一种基于排序熵和自互信息的自排序熵指标,定量描述表面肌电信号的内在动力学特性,实现肢体不同运动状态下肌电信号非线性特征的有效刻画.进行健康受试者上肢肘关节不同弯曲角度下表面肌电采集实验,计算其自排序熵指标并运用支持向量机进行动作识别,通过与已有表面肌电特征指标的对比分析,验证文中方法的有效性. 相似文献
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为了提高肌电信号多运动模式识别的准确性和实时性,提出了一种基于支持向量机的动作模式分类算法.在给出支持向量机的原理及其多类问题的基本算法基础上,着重介绍了两种改进的支持向量机多类识别算法,即有向无环图算法和基于先聚类后分类的二叉树算法,并比较了它们的优缺点.实验结果表明,针对前臂肌电信号的多运动模式分类,先聚类后分类的二叉树算法具有较高的分类准确性,更少的计算量,更好的实时性. 相似文献
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针对脑电信号(Electroencephalogram, EEG)采集易受干扰导致EEG分类准确率低的问题,提出一种基于共空间模式(Common Spatial Pattern, CSP)与决策树支持向量机法(Decision Tree Support Vector Machine, DTSVM)相融合的运动想象脑电信号处理方法。首先利用CSP算法对运动想象的EEG特征值进行特征提取,其次运用线性判别分析法(Linear Discriminant Analysis, LDA)、自适应增强分类法(Adaptive Boosting, Adaboost)和决策树支持向量机法分别对特征进行分类,最后通过实验对比发现,利用决策树支持向量机进行分类的分类效果最佳,分类准确率最高可达到92.52%。 相似文献
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《机器人》2017,(5)
针对人体步态识别率低的问题,提出了一种将核主成分分析(KPCA)和相关向量机(RVM)相结合的步态识别方法.首先,选择表面肌电信号(s EMG)作为步态识别信息源,提取表面肌电信号的小波包能量特征.然后,采用核主成分分析方法降维特征值去除冗余的信息,得到能反映步态特征的特征值.最后,利用相关向量机对步态特征向量进行分类,识别平地行走、上楼、下楼、上坡、下坡5种步态.通过分析不同受试者步态识别结果,验证了该方法的可行性和实用性,并和BP(反向传播)神经网络、SVM(支持向量机)等方法比较,结果表明该方法分类时间为2.6609×10~(-4)s,识别正确率为96.67%,是一种有效的步态识别方法. 相似文献
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Surface electromyography (SEMG) has been widely used in different fields such as human machine interaction and motion recognition. A hybrid classification model based on singular value decomposition (SVD) and wavelet deep belief networks (WDBN) is firstly proposed in this paper, which allows the machine to recognize the single-joint motions of upper limb by using one channel. In this experiment, the three-joint SEMG signals of upper limb are respectively recorded through different two channels, which are employed for subsequent comparison to obtain the best single-channel of each joint. Afterwards, the collected raw signals are enhanced by SVD processing. Wavelet function is applied to replace sigmoid function as activation function for feature learning, and the spectrum signals processed by fast Fourier transform (FFT) are input to WDBN model. The results demonstrate that the recognition rates of three joint movements can be up to 100% by SVD-WDBN method, which is much better than support vector machine (SVM), back propagation (BP) neural network and extreme learning machine (ELM) model. The proposed method makes it more possible to control wearable devices with different single-channel SEMG signals, thereby the work efficiency of smart wearable devices can be improved, as well as the complexity of operations between human and machine can be reduced. 相似文献
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Electroencephalography‐based feature extraction using complex network for automated epileptic seizure detection
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Electroencephalography signals are typically used for analyzing epileptic seizures. These signals are highly nonlinear and nonstationary, and some specific patterns exist for certain disease types that are hard to develop an automatic epileptic seizure detection system. This paper discussed statistical mechanics of complex networks, which inherit the characteristic properties of electroencephalography signals, for feature extraction via a horizontal visibility algorithm in order to reduce processing time and complexity. The algorithm transforms a time series signal into a complex network, which some features are abbreviated. The statistical mechanics are calculated to capture distinctions pertaining to certain diseases to form a feature vector. The feature vector is classified by multiclass classification via a k‐nearest neighbor classifier, a multilayer perceptron neural network, and a support vector machine with a 10‐fold cross‐validation criterion. In performance evaluation of proposed method with healthy, seizure‐free interval, and seizure signals, firstly, input data length is regarded among some practical signal samples by optimizing between accuracy‐processing time, and the proposed method yields outstanding performance on the average classification accuracy for 3‐class problems mainly for detection of seizure‐free interval and seizure signals and acceptable results for 2‐class and 5‐class problems comparing with conventional methods. The proposed method is another tool that can be used for classifying signal patterns, as an alternative to time/frequency analyses. 相似文献
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提出一种模式识别算法——双层支持量机算法,用来提高表面肌电识别精度。该算法融合集成学习中元学习的并行方法和叠加法的递进思想,把基本SVM分类器并行分布在第1层,第1层的预测结果作为第2层的输入,由第2层再进行分类识别,从而通过多层分类器组合来融合多源特征。以手臂表面肌电数据集为测试数据,采用文中的双层支持向量机,各肌肉的肌电信号分别输入基支持向量机,组合器融合各肌肉电信号特征,集成识别前臂肌肉群的肌电信号,从而实现运动意图的精确识别。实验结果显示,在预测精度上,此算法优于单个SVM分类器。在预测性能上(识别精度、耗时、鲁棒性),此算法优于随机森林和旋转森林等集成分类器。 相似文献
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由于支持向量机(SVM)在模式识别和回归分析中有着独特优势,因此成为近来研究的热点,其优势主要体现在处理非线性和高维数据问题方面。最初的SVM特别适合解决两类目标分类问题,而对于多类目标分类,则需将其转化为多个两类目标分类问题,相应地即可构造多个两类目标子分类器,但由于这种情况导致了分类器结构的过于复杂,从而导致判决速度的降低。为了快速地进行分类.提出了一种简化结构的多类目标分类器,其不仅使得子分类器数目大大减少,而且使分类速度明显提高;同时对其分类精度和复杂度进行了对比分析。实验结果证明。该分类器是有效的。 相似文献
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支持向量机(support vector machine, SVM)是一种基于结构风险最小化的机器学习方法, 能够有效解决分类问题. 但随着研究问题的复杂化, 现实的分类问题往往是多分类问题, 而SVM仅能用于处理二分类任务. 针对这个问题, 一对多策略的多生支持向量机(multiple birth support vector machine, MBSVM)能够以较低的复杂度实现多分类, 但缺点在于分类精度较低. 本文对MBSVM进行改进, 提出了一种新的SVM多分类算法: 基于超球(hypersphere)和自适应缩小步长果蝇优化算法(fruit fly optimization algorithm with adaptive step size reduction, ASSRFOA)的MBSVM, 简称HA-MBSVM. 通过拟合超球得到的信息, 先进行类别划分再构建分类器, 并引入约束距离调节因子来适当提高分类器的差异性, 同时采用ASSRFOA求解二次规划问题, HA-MBSVM可以更好地解决多分类问题. 我们采用6个数据集评估HA-MBSVM的性能, 实验结果表明HA-MBSVM的整体性能优于各对比算法. 相似文献
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针对多类运动想象脑电信号个体差异性强和分类正确率比较低的问题,提出了一种时-空-频域相结合的脑电信号分析方法:首先利用小波包对EEG原始信号进行分解,根据EEG信号的频域分布提取出运动想象脑电节律,通过“一对多”共空间模式(CSP)算法对不同运动想象任务的脑电节律进行空间滤波提取特征;然后将特征向量输入到“一对多”模式下的支持向量机(SVM)中,并利用判断决策函数值的方法对SVM的输出结果进行融合;最后通过引入时间窗对脑电信号进行时域滤波,消除运动想象开始和结束时脑电的波动,进一步提高信号信噪比和算法的分类效果;实验结果显示:在时间窗为2 s时,平均最大Kappa系数达到了0.72,比脑机接口竞赛第一名提高了0.15,验证了该算法能够有效减小脑电信号个体差异性影响,提高多类识别正确率。 相似文献
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支持向量机在机械故障诊断中的应用研究 总被引:20,自引:2,他引:20
在机械故障诊断中,通常不具备有大量的故障样本,因此,制约了故障诊断技术向智能化方向发展。而基于统计学习理论(SLT)的支持向量机(SVM)方法正好克服了这方面的不足。统计学习理论是专门研究少样本情况下的统计规律及学习方法的理论。SLT理论和SVM方法为故障诊断技术向智能化发展提供了新的途径。该文讨论了支持向量机在故障诊断领域中应用的分类算法。并以滚动轴承的振动信号为例进行了试验论证。试验表明:SVM方法对具有少样本的故障诊断领域具有很强的适应性。 相似文献
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基于支持向量机的机械故障智能分类研究 总被引:7,自引:0,他引:7
故障样本不足是制约故障诊断技术向智能化方向发展的主要原因之一,支持向量机(SVM)是一种基于统计学习理论(SLT)的机器学习算法,它能在训练样本很少的情况下达到很好的分类效果,从而为故障诊断技术向智能化发展提供了新的途径.本文介绍了支持向量机分类算法,以滚动轴承的故障分类为例,探讨了该算法在故障诊断领域中的应用,并与BP神经网络分类方法进行了对比研究,结果表明,SVM方法在少样本情况下的分类效果优于BP神经网络分类方法. 相似文献
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Bernd EhretAuthor Vitae Konstantin SafenreiterAuthor VitaeFrank LorenzAuthor Vitae Joachim BiermannAuthor Vitae 《Sensors and actuators. B, Chemical》2011,158(1):75-88
A new method for real time classification of volatile chemical substance traces is presented. The method is based on electrochemical signals of an array of semiconductor gas sensors. In these sensor signals characteristic patterns of different substances are hidden. There are non-linear correlative relationships between the measured sensor signals and the chemical substances which are treated using two methods derived from statistical learning theory (Support Vector Machine - SVM, Maximum Likelihood Estimation - MLE) for the detection of the substance characteristics in the sensor signals. A key criterion for the presented pattern recognition is a newly developed type of features, which is specially adapted to the low frequency signals of semiconductor sensors. The presented features are based on the evaluation of the range of the transient response in the sensor signals in the frequency domain.To derive the new features, both real measurement data and synthetic generated signals were used. In the experiments the focus was set on the creation of reproducible sensor signals to get characteristic signal patterns. Synthetic signals were derived from a Gaussian Plume Model. With the new features, training data sets were calculated using the classification methods SVM and MLE. With these training data sets new sensor measurements may be assigned to the substances which are to be sought. The advantage of the presented method is that no feature reduction is needed and no loss of information occurs in the learning process.The classification results based on the new features have been compared with the classification based on a conventional method for feature extraction. It was proved that the recognition rate of the substances used with the new feature type is higher.The substance classification is primarily limited by the sensitivity of the semiconductor sensors, because sufficiently large sensor signals must have been provided to obtain appropriate substance patterns. At the present stage of development the method presented is suitable for the classification of substance groups, such as nitro aromatics or alcohols, but not for specific substances. 相似文献
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雷金娥 《计算机工程与应用》2009,45(32):156-158
内容识别是视频和图像分析的主要目的之一,由于视频内容的复杂性,视频内容自动分析和识别并不容易实现,目前没有通用的视频行为识别方法和理论。三维各向异性扩散方程可以实现视频信号的多尺度分析,方便行为特征的描述和提取。通过多尺度分析结合支持向量机分类,可以系统地解决视频对象识别、运动识别和行为识别等一系列问题。实验表明,即使在样本行为特征未知的情况下,通过机器学习,也可以实现对视频行为的识别,说明这种行为识别方法可以用于任意已知样本的行为识别问题。 相似文献