基于改进KCCA的快速特征提取方法

KCCA特征提取技术具有处理非线性数据的良好性能,但是存在计算量大、特征提取缓慢的局限性.针对KCCA的这一缺点,在研究KCCA特征提取技术和SVDD分类理论的基础上,提出了一种基于改进KCCA的快速特征提取方法,并将改进后的KCCA与SVDD的优势相结合应用于人脸识别中.通过在ORL人脸库上的实验仿真和对比结果验证了所提出方法的有效性.     

模拟退火免疫粒子群算法在皮肤电信号情感识别中的应用

为了增强情感识别过程中皮肤电反应(GSR)信号特征选择的有效性,提出了一种改进的模拟退火免疫粒子群算法。首先,对342组被试6种情感的GSR信号进行去噪处理和原始特征提取;然后,将模拟退火机制引入到免疫粒子群(IPSO)算法的粒子更新过程中,使用新构造的模拟退火免疫粒子群(SA-IPSO)算法进行特征优化选择。实验表明:与IPSO相比,SA-IPSO能以较少特征获得较高的识别率,模拟退火机制的应用能更好地优化特征选择过程,且新的算法具有良好的全局收敛性能。     

基于遗传算法和支持向量数据描述的多项式轮廓内自相关过程监控

多项式轮廓数据在复杂产品制造过程中是一类广泛存在的质量数据类型。为了能尽快监测出多项式轮廓内自相关过程中的异常,针对仅存在正常样本的质量数据提出一种基于支持向量数据描述(SVDD)的监控方法。首先,消除轮廓间相关性,构建SVDD监控方法流程,运用遗传算法(GA)选择SVDD参数和核函数参数进行仿真;然后,通过仿真实验模拟得到平均运行长度,以平均运行长度为准则,对比分析采用高斯核函数和多项式核函数SVDD方法的监控性能;最后,与传统控制图进行对比。实验结果表明监控截距、一次项系数、二次项系数时,采用多项式核函数SVDD方法的失控平均运行长度小于T²、Tr_esidual²控制图,即监控效果优于其他控制图。     

用于不平衡数据分类的FE-SVDD算法

现有的支持向量数据描述(SVDD)算法在解决不平衡数据集问题时通常存在有偏性。针对该问题,在研究PCA特征提取技术和SVDD分类理论的基础上,提出一种用于平衡数据分类的FE-SVDD算法。该方法对2类样本数据进行主成分分析,分别求出主要特征值,根据样本容量及特征值对SVDD中的 值重新定义。在人工样本集和UCI数据集上进行实验,结果验证了该方法的有效性。     

基于主成分建模的SVDD高光谱图像异常检测

针对SVDD背景建模时混入异常点造成的检测率下降的问题,提出了基于主成分建模的SVDD方法并应用于高光谱图像异常检测。利用高光谱图像的光谱特征提取背景的主要成分,并分别对不同成分构建超球体,形成单种背景成分SVDD模型,最后利用综合决策函数对单个SVDD背景模型进行综合判断待检测像元,从而实现高光谱图像异常像元的检测。用仿真数据和真实数据对算法的性能进行验证,并将其与SVDD方法进行性能比较。结果表明,新算法在低虚警概率下较之SVDD模型有更高的检测概率,实验结果证明了算法的有效性。     

基于改进核典型相关分析的人脸识别方法

标准KCCA方法需要存储和计算核矩阵,而核矩阵的大小是训练样本数的平方,随着样本数的增加,计算量逐渐增大、特征提取缓慢.为了提高特征提取的效率,提出了一种基于特征向量集的KCCA特征提取方法.采用特征选择方法,选择一个训练样本子集并将其映射到再生核希尔伯特空间(RKHS).用KCCA进行特征提取,将计算复杂度由O(n3)降到O(Nl2)(L<相似文献   

支持向量数据描述的基因表达数据聚类方法

为改善传统的基因表达数据聚类方法正确率偏低的问题,研究了支持向量数据描述（SVDD）算法在基因表达数据聚类中的应用,该方法通过寻找最优分类超球实现对数据集的有效聚类.将类间信息融入聚类有效性评估准则中,通过模拟退火优化算法寻找SVDD算法中的最优核函数参数和惩罚因子,在训练时引入非样本数据提高运算效率.对酵母细胞生长周期的基因表达数据集的仿真实验结果表明,在新的聚类有效性评估准则下进行参数寻优,能够更快更好地得到最佳参数,同时,算法具有聚类精度高和运算速度快的优点.     

基于支持向量数据描述的网络可生存性综合评估

针对网络可生存性综合评估方法中指标权重难以确定的问题,提出了基于支持向量数据描述(SVDD)的网络可生存性综合评估方法。该方法分析了SVDD的几何意义,采用二进制粒子群(BPSO)算法对建立的评估特征指标集进行特征选择,将所得的特征指标集视为整体来建立SVDD分类模型,并以测试样本点与模型的相对距离为依据评估系统的可生存性,避免了综合评估中指标权重确定的主观性。最后通过网络实例验证了评估模型的有效性。     

一种新的特征提取方法及其在模式识别中的应用

核典型相关分析(KCCA)是一种有监督的机器学习方法,可以有效地提取非线性特征。然而随着训练样本数目的增加,标准的KCCA方法的计算复杂度会随之增加。针对此缺点,提出一种改进的KCCA方法：首先用几何特征选择方法选择一个训练样本子集并将其映射到再生核希尔伯特空间(RKHS),然后设计了一种提升特征提取效率的算法,该算法按照对特征分类贡献的大小巧妙地选取样本的特征值,进而求出其相应的特征向量,最后将改进的KCCA与支持向量数据描述(SVDD)多分类器相结合用于分类识别。在ORL人脸图像数据库上的实验结果表明,改进的方法相对传统的KCCA方法,在不影响识别率的情况下提高了人脸识别速度,减小了系统存储量。     

基于改进模拟退火算法的软件可靠性模型参数估计方法

为提升现有软件可靠性模型的拟合性能和求解精度,结合软件可靠性模型求解特征,提出一种改进的模拟退火算法。在此基础上,提出基于改进模拟退火算法的软件可靠性模型参数求解方法(简称为MSAE法),并将新方法应用于4组失效数据集。工程应用结果表明,与最大似然估计(MLE)法、和声搜索(HS)算法和蚁群(AC)算法相比,MSAE法可有效改善软件可靠性模型参数求解不收敛的情况,并且可以有效提升现有软件可靠性模型的拟合性能。     

OPTIMAL FEATURE SET AND PARAMETER SELECTION FOR POWER QUALITY DATA MINING

The significance of detection and classification of power quality (PQ) events that disturb the voltage and/or current waveforms in electrical power distribution networks is well known. Consequently, in spite of a large number of research reports in this area, research on the selection of useful features from the existing feature set and the parameter selection for specific classifiers has thus far not been explored. The choice of a smoothing parameter for a probabilistic neural network classifier (PNN) in the training process, together with feature selection, will significantly impact the classification accuracy. In this work, a thorough analysis is carried out, using two wrapper-based optimization techniques—the genetic algorithm and simulated annealing—for identifying the ensemble of celebrated features obtained using discrete wavelet transform together with the smoothing parameter selection of the PNN classifier. As a result of these analyses, the proper smoothing parameter together with a more useful feature set from among a wider set of features for the PNN classifier is obtained with improved classification accuracy. Furthermore, the results show that the performance of simulated annealing is better than the genetic algorithm for feature selection and parameter optimization in Power Quality Data Mining.     

基于模拟退火的多标记数据特征选择

多标记数据有很多的冗余特征和数据,为了解决多标记数据中冗余和无关特征,提高多标记学习算法的泛化能力。提出一个基于模拟退火的卷积式特征选择方法——SAML(simulated annealing based feature selection for multi-label data),已有的算法只是使用了遗传算法来进行优化,新算法采用模拟退火来寻找最优子集,其效果在已有的工作中表现出比前者遗传算法更好的效果。在用于公开评测的Yahoo网页分类数据集上的实验结果表明,SAML算法的性能优于新近提出的一些流行的多标记特征选择方法。     

A maximum-margin genetic algorithm for misclassification cost minimizing feature selection problem

We consider a feature selection problem where the decision-making objective is to minimize overall misclassification cost by selecting relevant features from a training dataset. We propose a two-stage solution approach for solving misclassification cost minimizing feature selection (MCMFS) problem. Additionally, we propose a maximum-margin genetic algorithm (MMGA) that maximizes margin of separation between classes by taking into account all examples as opposed to maximizing margin of separation using a few support vectors. Feature selection is carried out by either an exhaustive or a heuristic simulated annealing approach in the first stage and a cost sensitive classification using either MMGA or cost sensitive support vector machines (SVM) in the second stage. Using simulated and real-world data sets and different misclassification cost matrices, we test our two-stage approach for solving the MCMFS problem. Our results indicate that feature selection plays an important role when misclassification cost asymmetries increase and the MMGA shows equal or better performance than the SVM.     

Parameter determination of support vector machine and feature selection using simulated annealing approach

Support vector machine (SVM) is a novel pattern classification method that is valuable in many applications. Kernel parameter setting in the SVM training process, along with the feature selection, significantly affects classification accuracy. The objective of this study is to obtain the better parameter values while also finding a subset of features that does not degrade the SVM classification accuracy. This study develops a simulated annealing (SA) approach for parameter determination and feature selection in the SVM, termed SA-SVM.To measure the proposed SA-SVM approach, several datasets in UCI machine learning repository are adopted to calculate the classification accuracy rate. The proposed approach was compared with grid search which is a conventional method of performing parameter setting, and various other methods. Experimental results indicate that the classification accuracy rates of the proposed approach exceed those of grid search and other approaches. The SA-SVM is thus useful for parameter determination and feature selection in the SVM.     

森林优化特征选择算法的增强与扩展

特征选择作为一种重要的数据预处理方法,不但能解决维数灾难问题,还能提高算法的泛化能力.各种各样的方法已被应用于解决特征选择问题,其中,基于演化计算的特征选择算法近年来获得了更多的关注并取得了一些成功.近期研究结果表明,森林优化特征选择算法具有更好的分类性能及维度缩减能力.然而,初始化阶段的随机性、全局播种阶段的人为参数设定,影响了该算法的准确率和维度缩减能力;同时,算法本身存在着高维数据处理能力不足的本质缺陷.从信息增益率的角度给出了一种初始化策略,在全局播种阶段,借用模拟退火控温函数的思想自动生成参数,并结合维度缩减率给出了适应度函数;同时,针对形成的优质森林采取贪心算法,形成一种特征选择算法EFSFOA(enhanced feature selection using forest optimization algorithm).此外,在面对高维数据的处理时,采用集成特征选择的方案形成了一个适用于EFSFOA的集成特征选择框架,使其能够有效处理高维数据特征选择问题.通过设计对比实验,验证了EFSFOA与FSFOA相比在分类准确率和维度缩减率上均有明显的提高,高维数据处理能力更是提高...     

Solving optimization problems by parallel recombinative simulatedannealing on a parallel computer-an application to standard cellplacement in VLSI design

In this paper, parallel recombinative simulated annealing (PRSA), a hybrid method with features of simulated annealing and genetic algorithms, is examined. PRSA inherits the global convergence property from simulated annealing and the parallelism property from genetic algorithms. PRSA was implemented on a monoprocessor system as well as on a transputer. The algorithm, its parallel implementation, and its application to an NP-hard problem, namely standard cell placement in very large scale integration (VLSI) chip design, are described. PRSA was run for a large range of test cases. Since its performance depends on many parameters, the effects of parameter variations are studied in detail. Some important parameters are migration of individuals to other transputer nodes and selection strategies for constructing new populations. In comparison with simulated annealing and genetic algorithms, PRSA was found to produce better solutions.