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为了克服k-均值聚类算法容易受到数据空间分布影响的缺点,将线性规划下的一类支持向量机算法与K-均值聚类方法相结合提出一种支持向量聚类算法,该算法的每次循环都采用线性规划下的一类支持向量机进行运算.该算法实现简单,与二次规划下的支持向量机聚类算法相比,该算法能够大大减小计算的复杂性,而且能保持良好的聚类效果.与K-均值聚类算法、自组织映射聚类算法等进行仿真比较,人工数据和实际数据表明了该算法的有效性和可行性.  相似文献   

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针对航空发动机振动监控异常样本少的问题,用单类支持向量机建立了一种振动异常检测模型,在仅对正常数据进行训练的基础上便可以进行发动机振动异常检测工作.根据近期数据的重要性要大于早期数据的重要性这一特性,提出加权单类支持向量机算法,为不同架次的样本赋予不同的权系数.实验分析结果表明了检测模型的有效性.  相似文献   

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基于One-class SVM的实时入侵检测系统   总被引:1,自引:0,他引:1       下载免费PDF全文
黄谦  王震  韦韬  陈昱 《计算机工程》2006,32(16):127-129
将One-class支持向量机和Online训练算法应用于入侵检测研究中,把入侵检测看作是一种单值分类问题,能够在有噪声的数据集中进行训练,降低了对训练集的要求,提高了检测准确性。同时解决了基于SVM的入侵检测系统实时训练的问题,在实际运用中可以实时地添加新的训练样本对新出现的攻击手段进行分类。在KDD CUP’99标准入侵检测数据集上进行实验,系统缩短了训练时间并且获得了较高的检测准确率。  相似文献   

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人脸确认的动态支持向量数据描述方法   总被引:1,自引:0,他引:1       下载免费PDF全文
人脸的确认实质上是一个一类分类问题或野点检测问题,即只需要精确地描述某一类样本的分布,而将该类样本之外大范围内的样本点视为野点.为了能精确地描述某一类样本的分布,在对国内外现有统计学习理论和核方法进行研究的基础上,针对"人脸确认"这一特定的应用对象,分析了已有的一类分类算法,即支持向量数据描述方法在处理动态样本中存在的不足,进而指出,随着训练样本数目的增加,该算法会因为过大的优化规模而无法实际操作,为此提出了用于人脸确认的动态支持向量数据描述算法.由于新算法在优化过程中,仅需要考虑待检测样本和原有支持向量集,从而可以大大降低优化过程中涉及的运算规模和内存需求,进而可保证人脸确认过程中的实时性与动态性要求.  相似文献   

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提出一种基于遗传算法和多超球面一类支持向量机的隐秘图像检测方案。为了得到最能反映分类本质的特征从而有效实现分类识别,采用遗传算法进行图像特征选择,将支持向量机的分类效果作为适应度函数值返回,指导遗传算法搜索最优的特征选择方案。实验结果表明,与仅采用支持向量机分类而未进行特征选择的隐秘检测方案相比,该方案提高了隐秘图像检测的识别率。  相似文献   

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针对二类支持向量机分类器在隐秘图像检测中训练步骤复杂与推广性弱的缺点,提出了一种新的基于遗传算法和一类支持向量机的隐秘图像检测方案。采用遗传算法进行图像特征选择,一类支持向量机作为分类器。实验结果表明,与只利用一类支持向量机分类,但未进行特征选择的隐秘检测方法相比,提高了隐秘图像检测的识别率和系统检测效率。  相似文献   

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注册表作为Microsoft Windows操作系统的核心,控制着Windows整个系统的运行,而Micosoft Windows是目前应用最广泛,同时也是遭受恶意行为攻击最多的操作系统。针对这一现象,本文提出一种基于One-Class支持向量机的异常检测方法,利用Windows注册表建立入侵检测模型,通过支持向量机算法实时判断当前注册表的访问行为是否为异常状态来发现和识别入侵。实验表明,该方法对未知病毒和入侵行为具有较高的检测率,可以在先验知识较少的情况下提高学习机的推广能力;同时,利用One-Class支持向量机方法可以在不影响检测性能的条件下减少检测的反应时间,大大提高了检测系统的性能。  相似文献   

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研究基于支持向量机理论和单类分类思想的2种支持向量域数据描述模型,即单分类支持向量机和支持向量描述模型,分析2类模型之间的区别和联系以及参数的优化设置,总结支持向量域单分类方法存在的缺点以及目前对这2类支持向量描述模型研究的改进方向。  相似文献   

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提出了一种新的多类支持向量机算法OC-K-SVM.对k类分类问题,该方法构造了k个分类器,每一个分类器只对一类样本进行训练.使用Benchmark的数据集进行了初步的实验,实验结果验证了算法的有效性.  相似文献   

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传统支持向量机的时间空间复杂度和样本个数有关,样本个数大时,将产生时间空间上的巨大耗费。文章通过对一类问题最小包围球研究分析的基础上提出了一种简化算法,该算法对每一类别样本单独构造一个近似最小超球,不仅降低了二次规划问题的复杂度,而且易于扩充。仿真实验表明,该算法在不降低识别率的情况下,减少了支持向量的个数,降低了算法的复杂度。  相似文献   

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程序行为控制系统对程序行为进行建模、检测和响应。单类支持向量机(SVM)在有限样本的情况下用于异常检测,具有较好的分类精度和泛化能力。针对以前利用单类支持向量机进行异常检测的研究中没有考虑属性权重的问题,该文提出利用粗糙集理论(RST),引入反映属性重要性程度的权重值。给出通过找出决策系统中所有约简的集合确定属性权重的方法,并利用属性权重修正单类SVM的核函数。实验表明基于RST修正核的单类SVM具有更好的检测能力。  相似文献   

13.
张彬  朱嘉钢 《计算机科学》2016,43(12):135-138, 172
粗糙one-class支持向量机(ROC-SVM)在粗糙集理论基础上通过构建粗糙上超平面和下超平面来处理过拟合问题,但是在寻找最优分类超平面的过程中,忽略了训练样本类内结构这一非常重要的先验知识。因此,提出了一种基于类内散度的粗糙one-class支持向量机(WSROC-SVM),该方法通过最小化训练样本类内散度来优化训练样本类内结构,一方面使训练样本在高维特征空间中与坐标原点的间隔尽可能大,另一方面使得训练样本在粗糙上超平面尽可能紧密。在合成数据集和UCI数据集上的实验结果表明,较原始算法,该方法有着更高的识别率和更好的泛化性能,在解决实际分类问题上更具优越性。  相似文献   

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Despite extensive studies for the industrial applications of deep learning, its actual usage in manufacturing sites has been extremely restrained by the difficulty in obtaining sufficient industrial data, especially for production failure cases. In this study, we introduced a fault-detection module based on one-class deep learning for imbalanced industrial time-series data, which consists of three submodules, namely, time-series prediction based on deep learning, residual calculation, and one-class classification using one-class support vector machine and isolation forest. Four different networks were used for the time-series prediction: multilayer perception (MLP), residual network (ResNet), long–short-term memory (LSTM), and ResNet–LSTM, each trained with the one-class data having only the production success cases. We adopted the residuals of the deep-learning prediction as an elaborated feature for the construction of the one-class classification. We also tested the fault-detection module with the actual mass production data of a die-casting process. By adopting the features elaborated by the deep-learning time-series prediction, we showed that the total accuracy of the one-class classification significantly improved from 90.0% to 96.0%. Especially for its capability to detect production failures, the accuracy improved from 84.0% to 96.0%. The area under the receiver operating characteristics (AUROC) also improved from 87.56% to 98.96%. ResNet showed the best performance for detecting production failures, whereas ResNet–LSTM produced better results for ensuring the production success. Our results suggest that the one-class deep learning is a promising approach for extracting important features from time-series data to realize a one-class fault-detection module.  相似文献   

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Many applications of remote sensing only require the classification of a single land type. This is known as the one-class classification problem and it can be performed using either binary classifiers, by treating all other classes as the negative class, or one-class classifiers which only consider the class of interest. The key difference between these two approaches is in their training data and the amount of effort needed to produce it. Binary classifiers require an exhaustively labelled training data set while one-class classifiers are trained using samples of just the class of interest. Given ample and complete training data, binary classifiers generally outperform one-class classifiers. However, what is not clear is which approach is more accurate when given the same amount of labelled training data. That is, for a fixed labelling effort, is it better to use a binary or one-class classifier. This is the question we consider in this article. We compare several binary classifiers, including backpropagation neural networks, support vector machines, and maximum likelihood classifiers, with two one-class classifiers, one-class SVM, and presence and background learning (PBL), on the problem of one-class classification in high-resolution remote sensing imagery. We show that, given a fixed labelling budget, PBL consistently outperforms the other methods. This advantage stems from the fact that PBL is a positive-unlabelled method in which large amounts of readily available unlabelled data is incorporated into the training phase, allowing the classifier to model the negative class more effectively.  相似文献   

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This paper describes a new soft clustering algorithm in which each cluster is modelled by a one-class support vector machine (OC-SVM). The proposed algorithm extends a previously proposed hard clustering algorithm, also based on OC-SVM representation of clusters. The key building block of our method is the weighted OC-SVM (WOC-SVM), a novel tool introduced in this paper, based on which an expectation-maximization-type soft clustering algorithm is defined. A deterministic annealing version of the algorithm is also introduced, and shown to improve the robustness with respect to initialization. Experimental results show that the proposed soft clustering algorithm outperforms its hard clustering counterpart, namely in terms of robustness with respect to initialization, as well as several other state-of-the-art methods.  相似文献   

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粗糙one-class支持向量机   总被引:2,自引:2,他引:0  
粗糙集理论是处理不确定性和不完备信息的重要方法之一.通过将粗糙集理论引入到one-class支持向量机,提出了一种新颖的粗糙one-class支持向量机.通过定义上近似超平面和下近似超平面,使得训练样本能根据在粗糙间隔中的位置,自适应地对决策超平面产生影响.并且,outlier样本由于距离上近似超平面较近并产生较小的间隔误差,不会导致决策超平面对它们产生明显的过拟合.实验结果表明,粗糙one-class支持向量机的泛化性能优异,识别率和误识率均优于传统的one-class支持向量机.  相似文献   

18.
基于Contourlet变换和支持向量机提出了一种新的纹理图像检索方法。在这种方法中,能量和广义高斯分布参数被用做Contourlet子带图像的特征。通过这种表示,提出了由一类和二类支持向量机组成的两阶段检索算法来完成感知相似性测度。通过具有640个纹理图像的VisTex库和具有1760个纹理图像的Brodatz库证明了所提方法的有效性。实验结果表明,对于这两个纹理库,新的纹理图像检索方法的平均检索率分别达99.38%和98.07%。  相似文献   

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大规模高维不平衡数据是异常检测中的重大挑战.单类支持向量机在处理不平衡数据方面非常有效,但不适合大规模高维数据,同时单类支持向量机的核函数对检测性能也具有重要的影响.文中提出了一个深度自编码器与单类支持向量机相结合的异常检测模型,深度自编码器不仅负责提取特征和降维,同时拟合出了一个自适应核函数.深度自编码器与单类支持向...  相似文献   

20.
Novelty detection, also referred to as one-class classification, is the process of detecting ‘abnormal’ behavior in a system by learning the ‘normal’ behavior. Novelty detection has been of particular interest to researchers in domains where it is difficult or expensive to find examples of abnormal behavior (such as in medical/equipment diagnosis and IT network surveillance). Effective representation of normal data is of primary interest in pursuing one-class classification. While the literature offers several methods for one-class classification, very few methods can support representation of non-stationary classes without making stringent assumptions about the class distribution. This paper proposes a one-class classification method for non-stationary classes using a modified support vector machine and an efficient online version for reducing computational time. The presented method is applied to several simulated datasets and actual data from a drilling machine. In addition, we present comparison results with other methods that demonstrate its superior performance.  相似文献   

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