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1.
最小二乘支持向量机采用最小二乘线性系统代替传统的支持向量即采用二次规划方法解决模式识别问题,能够有效地减少计算的复杂性。但最小二乘支持向量机失去了对支持向量的稀疏性。文中提出了一种基于边界近邻的最小二乘支持向量机,采用寻找边界近邻的方法对训练样本进行修剪,以减少了支持向量的数目。将边界近邻最小二乘支持向量机用来解决由1-a-r(one-against-rest)方法构造的支持向量机分类问题,有效地克服了用1-a-r(one-against-rest)方法构造的支持向量机分类器训练速度慢、计算资源需求比较大、存在拒分区域等缺点。实验结果表明,采用边界近邻最小二乘支持向量机分类器,识别精度和识别速度都得到了提高。  相似文献   

2.
最小二乘支持向量机采用最小二乘线性系统代替传统的支持向量即采用二次规划方法解决模式识别问题,能够有效地减少计算的复杂性.但最小二乘支持向量机失去了对支持向量的稀疏性.文中提出了一种基于边界近邻的最小二乘支持向量机,采用寻找边界近邻的方法对训练样本进行修剪,以减少了支持向量的数目.将边界近邻最小二乘支持向量机用来解决由1-a-r(one-against-rest)方法构造的支持向量机分类问题,有效地克服了用1-a-r(one-against-rest)方法构造的支持向量机分类器训练速度慢、计算资源需求比较大、存在拒分区域等缺点.实验结果表明,采用边界近邻最小二乘支持向量机分类器,识别精度和识别速度都得到了提高.  相似文献   

3.
一种广义最小二乘支持向量机算法及其应用   总被引:1,自引:1,他引:0  
吴宗亮  窦衡 《计算机应用》2009,29(3):877-879
最小二乘支持向量机(LS SVM)是处理不可分样本集情况下模式分类的有效工具,但是该算法在处理很多实际分类问题时,表现出了一定的局限性。为了进一步增强最小二乘支持向量机的推广能力,提出一种通用的广义最小二乘支持向量机算法,并且把这种新算法首先应用到雷达一维距离像的识别中,实验表明新的算法能取得更好的识别效果。  相似文献   

4.
一种新型的多元分类支持向量机   总被引:3,自引:0,他引:3  
最小二乘支持向量机采用最小二乘线性系统代替传统的支持向量机采用二次规划方法解决模式识别问题。该文详细推理和分析了二元分类最小二乘支持向量机算法,构建了多元分类最小二乘支持向量机,并通过典型样本进行测试,结果表明采用多元分类最小二乘支持向量机进行模式识别是有效、可行的。  相似文献   

5.
一种快速最小二乘支持向量机分类算法   总被引:1,自引:1,他引:0       下载免费PDF全文
最小二乘支持向量机不需要求解凸二次规划问题,通过求解一组线性方程而获得最优分类面,但是,最小二乘支持向量机失去了解的稀疏性,当训练样本数量较大时,算法的计算量非常大。提出了一种快速最小二乘支持向量机算法,在保证支持向量机推广能力的同时,算法的速度得到了提高,尤其是当训练样本数量较大时算法的速度优势更明显。新算法通过选择那些支持值较大样本作为训练样本,以减少训练样本数量,提高算法的速度;然后,利用最小二乘支持向量机算法获得近似最优解。实验结果显示,新算法的训练速度确实较快。  相似文献   

6.
基于免疫优化多输出最小二乘支持向量机及其应用*   总被引:1,自引:0,他引:1  
传统的支持向量机是一种两类问题的判别方法, 不能直接应用于多类分类问题。为了解决这个问题,提出了一种免疫优化多输出最小二乘支持向量机方法。该方法利用免疫算法来优化最小二乘支持向量机的参数。将该方法应用于污水生化处理过程建模及语音情感识别,仿真结果表明,该方法具有更高的精度。  相似文献   

7.
陈圣磊  陈耿  薛晖 《计算机工程》2011,37(22):145-147
最小二乘支持向量机在提高求解效率的同时,会丧失解的稀疏性,导致其在预测新样本时速度较慢。为此,提出一种稀疏化最小二乘支持向量机分类算法。在特征空间中寻找近似线性无关向量组,构造分类判别函数的稀疏表示,相应的最小二乘支持向量机优化问题可以通过线性方程组求解,从而得到最优判别函数。实验结果表明,该算法在不损失分类精度的前提下,能够获得比最小二乘支持向量机更快的预测速度。  相似文献   

8.
最小二乘分解算法在车型识别中的应用   总被引:1,自引:0,他引:1  
周磊  冯玉田 《计算机仿真》2009,26(7):274-277
提出一种最小二乘支持向量机的序贯最小分类分解算法.针对最小二乘支持向量机,通过对核函数的相关变换,将二阶的误差信息归结到优化方程的一阶信息中,从而简化运算过程.采用最优函数梯度二阶信息选择工作集,实现最小二乘支持向量机分解算法,提高了算法的收敛性.采用径向基核函数和交叉验证网格搜索的方法验证算法的分类准确性.实验结果表明,提出的分类算法应用于车型识别中,可以得到比其他分类方法更好的分类准确度.  相似文献   

9.
一种稀疏最小二乘支持向量分类机   总被引:1,自引:0,他引:1  
一般的支持向量分类机需要求解二次规划问题,最小二乘支持向量机只需求解一个线性方程组,但其缺乏稀疏性.为了改进最小二乘支持向量分类机,本文结合中心距离比值及增量学习的思想提出一种基于预选、筛选支持向量的稀疏最小二乘支持向量机.该方法既能弥补最小二乘向量机的稀疏性,减少计算机的存储量和计算量,加快最小二乘支持向量机的训练速度和决策速度,又能对非均衡训练数据造成的分类面的偏移进行纠正,还不影响最小二乘支持向量机的分类能力.3组实验结果也证实了这一点.  相似文献   

10.
针对最小二乘支持向量机缺乏稀疏性的问题,提出了一种基于边界样本的最小二乘支持向量机算法。该算法利用中心距离比来选取支持度较大的边界样本作为训练样本,从而减少了支持向量的数目,提高了算法的速度。最后将该算法在4个UCI数据集上进行实验,结果表明:在几乎不损失精度的情况下,可以得到稀疏解,且算法的识别速度有了一定的提高。  相似文献   

11.
This paper proposed two psychophysiological-data-driven classification frameworks for operator functional states (OFS) assessment in safety-critical human-machine systems with stable generalization ability. The recursive feature elimination (RFE) and least square support vector machine (LSSVM) are combined and used for binary and multiclass feature selection. Besides typical binary LSSVM classifiers for two-class OFS assessment, two multiclass classifiers based on multiclass LSSVM-RFE and decision directed acyclic graph (DDAG) scheme are developed, one used for recognizing the high mental workload and fatigued state while the other for differentiating overloaded and base-line states from the normal states. Feature selection results have revealed that different dimensions of OFS can be characterized by specific set of psychophysiological features. Performance comparison studies show that reasonable high and stable classification accuracy of both classification frameworks can be achieved if the RFE procedure is properly implemented and utilized.  相似文献   

12.
支持向量机最初是针对两类分类问题提出的,如何有效地将其推广到多类分类问题仍是一项有待研究的课题。本文介绍了现有的具有代表性的多类支持向量机分类算法,并在分析决策导向非循环图支持向量机分类器生成顺序随机化的基础上,引入类内的分散度,以基于样本分布的类间分离程度作为类别的划分顺序,最终构成了一种分类间隔较大的决策导向非循环图支持向量机分类算法。实验结果表明了本文方法具有更高的分类精度。  相似文献   

13.
Based on the principle of one-against-one support vector machines (SVMs) multi-class classification algorithm, this paper proposes an extended SVMs method which couples adaptive resonance theory (ART) network to reconstruct a multi-class classifier. Different coupling strategies to reconstruct a multi-class classifier from binary SVM classifiers are compared with application to fault diagnosis of transmission line. Majority voting, a mixture matrix and self-organizing map (SOM) network are compared in reconstructing the global classification decision. In order to evaluate the method’s efficiency, one-against-all, decision directed acyclic graph (DDAG) and decision-tree (DT) algorithm based SVM are compared too. The comparison is done with simulations and the best method is validated with experimental data.  相似文献   

14.
In this paper, a classifier motivated from statistical learning theory, i.e., support vector machine, with a new approach based on multiclass directed acyclic graph has been proposed for classification of four types of electrocardiogram signals. The motivation for selecting Directed Acyclic Graph Support Vector Machine (DAGSVM) is to have more accurate classifier with less computational cost. Empirical mode decomposition and subsequently singular value decomposition have been used for computing the feature vector matrix. Further, fivefold cross-validation and particle swarm optimization have been used for optimal selection of SVM model parameters to improve the performance of DAGSVM. A comparison has been made between proposed algorithm and other two classifiers, i.e., K-Nearest Neighbor (KNN) and Artificial Neural Network (ANN). The DAGSVM has yielded an average accuracy of 98.96% against 95.83% and 96.66% for the KNN and the ANN, respectively. The results obtained clearly confirm the superiority of the DAGSVM approach over other classifiers.  相似文献   

15.
孪生支持向量机(TWSVM)的研究是近来机器学习领域的一个热点。TWSVM具有分类精度高、训练速度快等优点,但训练时没有充分利用样本的统计信息。作为TWSVM的改进算法,基于马氏距离的孪生支持向量机(TMSVM)在分类过程中考虑了各类样本的协方差信息,在许多实际问题中有着很好的应用效果。然而TMSVM的训练速度有待提高,并且仅适用于二分类问题。针对这两个问题,将最小二乘思想引入TMSVM,用等式约束取代TMSVM中的不等式约束,将二次规划问题的求解简化为求解两个线性方程组,得到基于马氏距离的最小二乘孪生支持向量机(LSTMSVM),并结合有向无环图策略(DAG)设计出基于马氏距离的最小二乘孪生多分类支持向量机。为了减少DAG结构的误差累积,构造了基于马氏距离的类间可分性度量。人工数据集和UCI数据集上的实验均表明,所提算法不仅有效,而且相对于传统多分类SVM,其分类性能有明显提高。  相似文献   

16.
任海鹏  马展峰 《自动化学报》2011,37(11):1407-1412
针对带钢表面缺陷识别问题,提出一种基于动态演化复杂网络特性的特征描述方法, 这些特征同时具有位移、旋转不变性、大小不变性、较强的抗干扰能力和鲁棒性,为 缺陷识别提供良好的分类特征;为了提高分类器的效率,应用主成分分析法 (Principal component analysis, PCA) 对复杂网络特 征向量进行特征降维处理;采用最优有向无环图支持向量机 (Directed acyclic graph support vector machine, DAG-SVM)算法进行缺陷分类.结果表明该方法识别率高而且识别速度快.  相似文献   

17.
为提高导引头故障诊断准确率,提出了一种采用改进遗传算法优化的最小二乘支持向量机(LSSVM)构造导引头多故障分类模型的方法。该方法基于一对一策略及改进的投票法建立两层LSSVM多故障分类器,并利用一种自适应变步长搜索策略改进的遗传算法对LSSVM的核参数和正则化参数进行自动优选。通过对某型导引头实测数据的仿真并和标准SVM及BP神经网络诊断方法相比较,结果表明该方法具有更高诊断准确率和计算效率。  相似文献   

18.
Pattern Analysis and Applications - In this paper, a new epileptic seizure detection method using fuzzy-rules-based sub-band specific features and layered directed acyclic graph support vector...  相似文献   

19.
There is a commonly held opinion that the algorithms for learning unrestricted types of Bayesian networks, especially those based on the score+search paradigm, are not suitable for building competitive Bayesian network-based classifiers. Several specialized algorithms that carry out the search into different types of directed acyclic graph (DAG) topologies have since been developed, most of these being extensions (using augmenting arcs) or modifications of the Naive Bayes basic topology. In this paper, we present a new algorithm to induce classifiers based on Bayesian networks which obtains excellent results even when standard scoring functions are used. The method performs a simple local search in a space unlike unrestricted or augmented DAGs. Our search space consists of a type of partially directed acyclic graph (PDAG) which combines two concepts of DAG equivalence: classification equivalence and independence equivalence. The results of exhaustive experimentation indicate that the proposed method can compete with state-of-the-art algorithms for classification.Editors: Pedro Larrañaga, Jose A. Lozano, Jose M. Peña and Iñaki Inza  相似文献   

20.
We present a new architecture named Binary Tree of support vector machine (SVM), or BTS, in order to achieve high classification efficiency for multiclass problems. BTS and its enhanced version, c-BTS, decrease the number of binary classifiers to the greatest extent without increasing the complexity of the original problem. In the training phase, BTS has N-1 binary classifiers in the best situation (N is the number of classes), while it has log/sub 4/3/((N+3)/4) binary tests on average when making a decision. At the same time the upper bound of convergence complexity is determined. The experiments in this paper indicate that maintaining comparable accuracy, BTS is much faster to be trained than other methods. Especially in classification, due to its Log complexity, it is much faster than directed acyclic graph SVM (DAGSVM) and ECOC in problems that have big class number.  相似文献   

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