An Algorithm for Idle-State Detection and Continuous Classifier Design in Motor-Imagery-Based BCI

The development of asynchronous braincomputer interface (BCI) based on motor imagery (MI) poses the research in algorithms for detecting the nontask states (i.e., idle state) and the design of continuous classifiers that classify continuously incoming electroencephalogram (EEG) samples. An algorithm is proposed in this paper which integrates two two-class classifiers to detect idle state and utilizes a sliding window to achieve continuous outputs. The common spatial pattern (CSP) algorithm is used to extract features of EEG signals and the linear support vector machine (SVM) is utilized to serve as classifier. The algorithm is applied on dataset IVb of BCI competition III, with a resulting mean square error of 0.66. The result indicates that the proposed algorithm is feasible in the first step of the development of asynchronous systems.     

Common Spatial Pattern Ensemble Classifier and Its Application in Brain-Computer Interface

Abstract-Common spatial pattern （CSP） algorithm is a successful tool in feature estimate of brain-computer interface （BCI）. However, CSP is sensitive to outlier and may result in poor outcomes since it is based on pooling the covariance matrices of trials. In this paper, we propose a simple yet effective approach, named common spatial pattern ensemble （CSPE） classifier, to improve CSP performance. Through division of recording channels, multiple CSP filters are constructed. By projection, log-operation, and subtraction on the original signal, an ensemble classifier, majority voting, is achieved and outlier contaminations are alleviated. Experiment results demonstrate that the proposed CSPE classifier is robust to various artifacts and can achieve an average accuracy of 83.02%.     

Common Spatial Pattern Ensemble Classifier and Its Application in Brain-Computer Interface

Common spatial pattern (CSP) algorithm is a successful tool in feature estimate of brain-computer interface (BCI). However, CSP is sensitive to outlier and may result in poor outcomes since it is based on pooling the covariance matrices of trials. In this paper, we propose a simple yet effective approach, named common spatial pattern ensemble (CSPE) classifier, to improve CSP performance. Through division of recording channels, multiple CSP filters are constructed. By projection, log-operation, and subtraction on the original signal, an ensemble classifier, majority voting, is achieved and outlier contaminations are alleviated. Experiment results demonstrate that the proposed CSPE classifier is robust to various artifacts and can achieve an average accuracy of 83.02%.     

Semi-Supervised Learning Based on Manifold in BCI

Abstract-A Laplacian support vector machine （LapSVM） algorithm, a semi-supervised learning based on manifold, is introduced to brain-computer interface （BCI） to raise the classification precision and reduce the subjects＇ training complexity. The data are collected from three subjects in a three-task mental imagery experiment. LapSVM and transductive SVM （TSVM） are trained with a few labeled samples and a large number of unlabeled samples. The results confirm that LapSVM has a much better classification than TSVM.     

Recognition of motor imagery tasks for BCI using CSP and chaotic PSO twin SVM

Accurate modeling and recognition of the brain activity patterns for reliable communication and interaction are still a challenging task for the motor imagery (MI) brain-computer interface (BCI) system. In this paper, we propose a common spatial pattern (CSP) and chaotic particle swarm optimization (CPSO) twin support vector machine (TWSVM) scheme for classification of MI electroencephalography (EEG). The self-adaptive artifact removal and CSP were used to obtain the most distinguishable features. To improve the recognition results, CPSO was employed to tune the hyper-parameters of the TWSVM classifier. The usefulness of the proposed method was evaluated using the BCI competition IV-IIa dataset. The experimental results showed that the mean recognition accuracy of our proposed method was increased by 5.35%, 4.33%, 0.78%, 1.45%, and 9.26% compared with the CPSO support vector machine (SVM), particle swarm optimization (PSO) TWSVM, linear discriminant analysis LDA), back propagation (BP) and probabilistic neural network (PNN), respectively. Furthermore, it achieved a faster or comparable central processing unit (CPU) running time over the traditional SVM methods.     

一种基于支撑矢量机的多用户检测算法

与现有的机器学习算法相比,在样本有限的情况下,支撑矢量机具有更强的分类推广能力.本文将支撑矢量机与多用户检测相结合,提出了一种新型的多用户检测算法.理论推导和仿真结果表明该算法的有效性.     

基于聚类支持向量机的入侵检测算法

针对支持向量机应用到入侵检测中训练时间长的特点,提出了一种基于聚类的支持向量机的入侵检测算法。该方法可以对训练数据进行剪枝,以靠近判别边界的聚类中心集合作为有效的训练样本集合对支持向量机进行训练,减少了样本的训练时间,提高了算法的效率。实验结果表明该方法对入侵检测是有效的。     

Boosting算法在入侵检测中的应用

将一种基于支持向量机的Boosting算法应用于入侵检测,并通过KDD’99数据的仿真实验将它与单一的支持向量机分类器进行比较,结果表明Boosting算法比单一的支持向量机分类器具有更好的检测效果。     

基于单目视觉的行人检测研究

行人检测系统是目前先进驾驶辅助系统中直接面向行人的保护系统,可最大程度地减少行人所受到的伤害。纹理对称度特征是目前最直观且能够用于表征行人的特征。文中在采用基于纹理对称度特征方法提取感兴趣区域的基础上,提出了一种线检测的方法,可以有效地减少检测过程中阴影、树叶等小纹理对检测结果的影响。最后利用梯度方向直方图特征和支持向量机方法对感兴趣区域进行验证。试验结果表明,该方法在保证检测速度的前提下,可减少检测过程中的虚警和漏警情况。     

一种基于类融合向量的支持向量机及其在语音识别系统中的应用

支持向量机可以通过产生的支持向量来概括数据集合中的信息,其分类函数仅依赖于一小部分训练样本,即支持向量,这使得它对噪声数据非常敏感.本文采用数据融合的方法加以改进,提出了一种新的基于类融合向量的支持向量机,降低了对噪声数据和较大偏差值的敏感性,提高了算法的容噪性能,并成功地应用于语音识别系统中,取得了较好的效果.     

音频事件检测算法在计量费控用电压开关柜局部放电检测中的应用研究

有效检测开关柜故障是影响电网安全的因素,如何进行有效的非浸入式检测是国内外的研究热点之一。提出一种基于音频信号的电压开关柜局部放电检测算法,可识别开关柜正常态、电晕态和放电态3种状态。算法首先提取电压开关柜放电声音的MFCC特征作为识别特征,然后构建基于支持向量机的分类器来识别出电压开关柜的状态,从而进行故障检测。实验表明本文提出的检测算法具有较高的局部放电检测正确率。     

压缩域中基于支持向量机的镜头边界检测算法

针对如何进一步提高镜头边界检测精度问题,本文提出了一个基于支持向量机SVM (Support Vector Machine)的镜头边界检测算法.该算法利用视频压缩域中特征,如宏块类型,帧间对应宏块DC系数差和帧类型将视频帧分为发生切变的帧、发生渐变的帧和非镜头变换帧三类,从而实现视频的镜头分割.实验结果表明该算法对摄像机的运动和大物体的进入具有很好的鲁棒性,且没有大多数算法中阈值选择的困难,将我们的算法与2001 TREC评估中最佳指标进行了比较,在综合度量查全率和查准率的性能指标F1上,比2001 TREC评估中最佳指标高约8％.     

一种陶瓷方形扁平封装外观缺陷检测方法

提出一种基于机器视觉的陶瓷方形扁平封装外观缺陷检测方法。对于封装外形尺寸较大而缺陷较细微的情形,将待检片分为多个区域与标准样片进行比对检测。首先通过Foerstner特征点检测法提取标准片图像的特征点,然后使用随机抽样一致性(RANSAC)图像匹配算法,将所有标准片图像拼接并融合生成一张标准片全幅面模板,再将待检片分区与标准片模板进行序贯比对,以提取可疑区域,最后利用支持向量机(SVM)分类器对可疑区域进行筛选分类。实验结果表明,这种方法不仅克服了传统视觉检测过程中视野范围与图像分辨率相互制约的矛盾,且对陶瓷方形扁平封装表面缺陷具有较高的检出率。     

基于颜色与肤色特征的视频过滤算法

互联网技术飞速发展给人们带来便利的同时,网络上大量色情淫秽等不良信息极大地干扰了正常的网络生活。根据当今网络不良视频的特点,文中提出了一种基于MPEG-7颜色描述子与动态肤色检测技术相结合的视频过滤算法。该算法综合考虑视频的静态信息和动态信息,采用支持向量机（SVM）进行学习分类,综合两类特征得到最终结果。通过实验分析,该算法有效提高了分类准确率,在当今网络环境中有着广泛的应用前景。     

基于PSO-SVM算法的雷达点迹真伪鉴别方法研究

为解决虚假目标点迹对雷达跟踪性能的影响,本文提出了一种基于PSO-SVM算法的雷达点迹真伪鉴别方法,进一步对目标点迹和杂波点迹进行真伪鉴别,有助于滤除杂波剩余点迹,提高雷达处理容量和跟踪性能。本方法利用点迹形成过程中生成的特征参数,先利用PSO算法对SVM算法参数进行优化选择,再利用参数优化后的SVM算法对雷达点迹进行真伪鉴别。最终,目标点迹鉴别准确率达到了95.18%,杂波点迹鉴别准确率达到了89.94%,整体的点迹鉴别准确率达到了92.13%。实验结果表明：该算法有较高、较稳定的点迹鉴别准确率,前期较多的杂波点迹被鉴别为目标点迹的缺陷也得到了较好的改善。     

基于模糊识别和支持向量机的联合Rootkit动态检测技术研究

针对Rootkit恶意代码动态检测技术进行研究.总结出典型Rootkit恶意程序动态行为所调用的系统API函数.实时统计API调用序列生成元并形成特征向量,通过模糊隶属函数和模糊权向量,采用加权平均法得到模糊识别的评估结果;基于层次的多属性支持向量机分析法构建子任务;基于各个动态行为属性的汉明距离定位Rootkit的类型.提出的动态检测技术提高了自动检测Rootkit的准确率,也可以用于检测未知类型恶意代码.     

基于数字信号处理器的激光成像雷达目标识别算法实现

激光成像雷达的空间分辨率较高,能成四维像(强度像 三维距离像),适合作目标识别探测器.支持向量机(SVM)是一种能在小样本学习的情况下,仍有较高识别正确率的目标识别方法.通过优化支持向量机算法,将它嵌入到激光成像雷达系统的数字信号处理器(DSP)芯片内,实现目标识别的功能,有很高的现实意义.首先用真实激光成像雷达强度像做实验,测试56个样本,共耗时31.97μs,证明嵌入到数字信号处理器的支持向量机算法能满足实时性要求,识别正确率为98.2%;再用仿真激光成像雷达距离像验证支持向量机的推广能力,证明支持向量机在实时性和识别性能两方面都能满足激光成像雷达的识别要求.     

A Novel Algorithm of Water Region Detection in SAR Image Based on Bag of Visual Words and Local Pattern Histogram

Water region detection based on SAR images is a difficult problem for its computing complexity.This paper proposes a novel water region detection method in SAR image of complex scenery.The algorithm takes advantages of Bag of visual words (BOV) to precisely describe the homogeneous region in complex scenery.Local pattern histogram (LPH) and single-class Support vector machine (SVM) are adopted to determine the edge information of water region precisely.The feature extraction is calculated block by block,which reduces computing workload and interference from noise.The experiments based on SAR images of real complex scenery show that the proposed method achieves higher accuracy and robustness.     

基于样本约简的实时 SVDD 算法与电路故障检测应用

针对支持向量数据描述（SVDD）训练大规模样本时计算复杂度太大的问题,提出了一种基于样本约简的实时SVDD算法。该算法首先通过随机抽样的方法从原始样本集中抽取一定规模样本用于SVDD训练;然后用训练得到的支持向量对特征空间中的样本中心进行估计;最后计算原始样本集中所有样本到中心的距离,并对所有距离按降序排列,通过提取一定比例距离较大的样本作为训练样本集对SVDD进行训练,最终实现了训练样本规模约简。实验结果表明：算法有效削减了训练复杂度,满足了SVDD故障检测的实时性要求。