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1.
Support vector machine (SVM) has become a dominant classification technique used in pedestrian detection systems. In such systems, classifiers are used to detect pedestrians in some input frames. The performance of a SVM classifier is mainly influenced by two factors: the selected features and the parameters of the kernel function. These two factors are highly related and therefore, it is desirable that the two factors can be analyzed simultaneously, which are usually not the case in the previous work.In this paper, we propose an evolutionary method to simultaneously optimize the feature set and the parameters for the SVM classifier. Specifically, adaptive genetic operators were designed to be suitable for the feature selection and parameter tuning. The proposed method is used to train a SVM classifier for pedestrian detection. Experiments in real city traffic scenes show that the proposed approach leads to higher detection accuracy and shorter detection time.  相似文献   

2.
Selecting relevant features for support vector machine (SVM) classifiers is important for a variety of reasons such as generalization performance, computational efficiency, and feature interpretability. Traditional SVM approaches to feature selection typically extract features and learn SVM parameters independently. Independently performing these two steps might result in a loss of information related to the classification process. This paper proposes a convex energy-based framework to jointly perform feature selection and SVM parameter learning for linear and non-linear kernels. Experiments on various databases show significant reduction of features used while maintaining classification performance.  相似文献   

3.
The efficiency of the intrusion detection is mainly depended on the dimension of data features. By using the gradually feature removal method, 19 critical features are chosen to represent for the various network visit. With the combination of clustering method, ant colony algorithm and support vector machine (SVM), an efficient and reliable classifier is developed to judge a network visit to be normal or not. Moreover, the accuracy achieves 98.6249% in 10-fold cross validation and the average Matthews correlation coefficient (MCC) achieves 0.861161.  相似文献   

4.
An improved discriminative common vectors and support vector machine based face recognition approach is proposed in this paper. The discriminative common vectors (DCV) algorithm is a recently addressed discriminant method, which shows better face recognition effects than some commonly used linear discriminant algorithms. The DCV is based on a variation of Fisher’s Linear Discriminant Analysis for the small sample size case. However, for multiclass problem, the Fisher criterion is clearly suboptimal. We design an improved discriminative common vector by adjustment for the Fisher criterion that can estimate the within-class and between-class scatter matrices more accurately for classification purposes. Then we employ support vector machine as the classifier due to its higher classification and higher generalization. Testing on two public large face database: ORL and AR database, the experimental results demonstrate that the proposed method is an effective face recognition approach, which outperforms several representative recognition methods.  相似文献   

5.
This paper introduces a cylindricity evaluation algorithm based on support vector machine learning with a specific kernel function, referred to as SVR, as a viable alternative to traditional least square method (LSQ) and non-linear programming algorithm (NLP). Using the theory of support vector machine regression, the proposed algorithm in this paper provides more robust evaluation in terms of CPU time and accuracy than NLP and this is supported by computational experiments. Interestingly, it has been shown that the SVR significantly outperforms LSQ in terms of the accuracy while it can evaluate the cylindricity in a more robust fashion than NLP when the variance of the data points increases. The robust nature of the proposed algorithm is expected because it converts the original nonlinear problem with nonlinear constraints into other nonlinear problem with linear constraints. In addition, the proposed algorithm is programmed using Java Runtime Environment to provide users with a Web based open source environment. In a real-world setting, this would provide manufacturers with an algorithm that can be trusted to give the correct answer rather than making a good part rejected because of inaccurate computational results.  相似文献   

6.
基于统计检测的方法,提出了一种基于遗传蚂蚁算法与支持向量机联合优化的入侵检测技术.本算法在利用遗传蚂蚁算法对数据特征进行提取的同时,对支持向量机参数进行优化,利用遗传算法快速得到局部最优值,然后利用蚂蚁算法的全局搜索特点得到全局最优值,从而可以明显提高入侵检测正确率,缩短检测时间.仿真表明,本算法检测正确率与本文提到的其他方法相比明显提高.  相似文献   

7.
SVM has been receiving increasing interest in areas ranging from its original application in pattern recognition to other applications such as regression estimation due to its remarkable generalization performance. Unfortunately, SVM is currently considerably slower in test phase caused by number of the support vectors, which has been a serious limitation for some applications. To overcome this problem, we proposed an adaptive algorithm named feature vectors selection (FVS) to select the feature vectors from the support vector solutions, which is based on the vector correlation principle and greedy algorithm. Through the adaptive algorithm, the sparsity of solution is improved and the time cost in testing is reduced. To select the number of the feature vectors adaptively by the requirements, the generalization and complexity trade-off can be directly controlled. The computer simulations on regression estimation and pattern recognition show that FVS is a promising algorithm to simplify the solution for support vector machine.  相似文献   

8.
基于支持向量机的图像型火灾探测算法   总被引:1,自引:0,他引:1  
针对传统火灾探测方法存在的不足,提出了一种基于支持向量机的图像型火灾探测算法,并与基于神经网络的图像型火灾探测算法做了比较。实验结果表明支持向量机克服了神经网络容易过学习、容易陷入局部极小点等不足,同时避免了人为设定特征量识别阈值时需要做大量实验和统计的复杂性。基于支持向量机的图像型火灾探测算法识别准确率高,对于小样本、高维数、非线性的分类问题效果显著。  相似文献   

9.
10.
基于快速支持向量机的图像型火灾探测算法*   总被引:1,自引:0,他引:1  
图像型火灾探测的核心问题是火焰和疑似火焰物体的分类和识别。以火灾视频和疑似火灾视频为分析对象,提取了火灾图像的面积重叠率、圆形度以及火焰尖角数目三个特征量,选择快速支持向量机进行分类器训练,最终利用训练好的分类器实现了火焰及干扰物体的分类识别问题。实验结果表明,该算法提高了火灾图像的分类精度和火灾识别的准确率,同时具有较高的检测效率。  相似文献   

11.
HOG特征对行人轮廓有很好的描述能力,但基于HOG特征的行人检测存在检测速度慢、漏检率较高的问题,使得该算法的实践应用范围受限。本文针对检测速度慢、漏检率较高的问题,提出了一种基于PHOG特征的行人检测算法。首先,提出了PHOG特征,该特征对cell内的梯度特征进行强化,增大了目标与背景的梯度分布区别,从而使目标更容易被分类器学习和识别。然后提出了构建特征金字塔的方法,并对PHOG特征进行有效地降维,大幅度减少了检测时间。试验结果表明,本文提出的PHOG-PCA特征将漏检率从35%降到了22%,检测速度也比一些流行算法快。  相似文献   

12.
A parallel randomized support vector machine (PRSVM) and a parallel randomized support vector regression (PRSVR) algorithm based on a randomized sampling technique are proposed in this paper. The proposed PRSVM and PRSVR have four major advantages over previous methods. (1) We prove that the proposed algorithms achieve an average convergence rate that is so far the fastest bounded convergence rate, among all SVM decomposition training algorithms to the best of our knowledge. The fast average convergence bound is achieved by a unique priority based sampling mechanism. (2) Unlike previous work (Provably fast training algorithm for support vector machines, 2001) the proposed algorithms work for general linear-nonseparable SVM and general non-linear SVR problems. This improvement is achieved by modeling new LP-type problems based on Karush–Kuhn–Tucker optimality conditions. (3) The proposed algorithms are the first parallel version of randomized sampling algorithms for SVM and SVR. Both the analytical convergence bound and the numerical results in a real application show that the proposed algorithm has good scalability. (4) We present demonstrations of the algorithms based on both synthetic data and data obtained from a real word application. Performance comparisons with SVMlight show that the proposed algorithms may be efficiently implemented.  相似文献   

13.
支持向量机在入侵检测中的应用   总被引:1,自引:1,他引:1  
入侵检测是网络安全的重要领域.安全问题的日益严峻对于检测方法提出更高的要求.支持向量机是一种基于小样本学习的有效工具.继它在字体识别,人脸识别中得到成功应用后,它被成功地应用到入侵检测领域中.介绍了支持向量机的多种算法,例如二分类的支持向量机,一分类的支持向量机,多分类的支持向量机和针对大量训练样本的支持向量机在入侵检测中的应用.通过比较发现,用支持向量机进行检测入侵大大提高了入侵检测系统的性能.  相似文献   

14.
为了有效提升支持向量机的泛化性能,提出两种集成算法对其进行训练.首先分析了扰动输入特征空间和扰动模型参数两种方式对于增大成员分类器之间差异性的作用;然后提出两种基于二重扰动机制的集成训练算法.其共同特点是,同时扰动输入特征空间和模型参数以产生成员分类器,并利用多数投票法对它们进行组合.实验结果表明,因为同时缩减了误差的偏差部分和方差部分,所以两种算法均能显著提升支持向量机的泛化性能.  相似文献   

15.
The development of an automated health monitoring framework is critical for aviation system safety, especially considering the expected increase in air traffic over the next decade. Conventional approaches such as model-based and exceedance methods have a low detection accuracy and are limited to specific applications. This paper proposes a robust real-time health monitoring framework for detecting performance anomalies, which may impact system safety during flight operations, with high accuracy and generalized applicability. The proposed monitoring framework utilizes sensor data from commercial flight data recorders to predict possible flight performance anomalies. Decimation, a signal processing technique, in conjunction with Savitzky-Golay filtering is utilized to preprocess the dataset and mitigate sampling rate and noise issues that prevent direct usage of historical flight data. Correlation-based feature subset selection is subsequently performed, and these features are used to train a support vector machine that predicts flight performance. With this model, performance anomalies in the test data are automatically detected based on deviations from the predicted flight behavior. The proposed monitoring framework was demonstrated to detect performance anomalies in real-time and exhibited accurate detection capabilities with high computational efficiency.  相似文献   

16.
目的 目标在跟踪过程中,各种因素的干扰使得跟踪结果存在不确定性。因此,将跟踪过程中所提取样本的可靠性融入跟踪模型中,有助于克服低可靠性样本对跟踪算法的影响。为此,基于最近的结构化支持向量机(SSVM)跟踪算法,提出一种包含样本置信度的加权间隔结构化支持向量机跟踪模型(WMSSVM),以增强SSVM跟踪算法性能。方法 首先,基于打分和位置重合率估计样本可靠性;其次,建立WMSSVM模型处理具有不同置信度的跟踪样本训练问题,并采用对偶坐标下降优化算法求解跟踪模型。结果 在包含100个视频的OTB100跟踪数据集上进行测试,提出的WMSSVM跟踪器与基准跟踪器Scale-DLSSVM相比,在精准度和成功率两个指标上分别提高了1%和2%。与最近的跟踪算法相比,提出的方法也表现出更好的性能。结论 本文首次将样本的可靠性融入结构化支持向量机跟踪模型,并提出一种基于加权间隔的结构化支持向量机跟踪模型及其优化求解方法,在包含100个视频序列的跟踪数据集上验证了提出方法的有效性,本文提出的算法能够适应复杂场景下的跟踪任务,并在背景混杂、目标形变、遮挡、运动模糊、目标出界、快速位移等类别的视频中表现出优异的性能。  相似文献   

17.
在生物信息学中,对给定氨基酸序列的蛋白质进行分类,检测细微的蛋白质序列相似性或远同源性对于准确预测蛋白质功能和结构都非常重要。提出一种新的基于半监督支持向量机的远同源性检测方法,通过定义序列概率剖面,充分利用大型数据库的非标记数据,并行构筑支持向量机核函数,并结合最近邻分类器实现对任何数据的全覆盖。实验表明,该方法能够大幅提高蛋白质序列分类器的性能与效率。使用并行技术将总体计算时间控制在一定范围,推动了半监督支持向量机分类器的广泛应用。  相似文献   

18.
Transductive support vector machine (TSVM) is a well-known algorithm that realizes transductive learning in the field of support vector classification. This paper constructs a bi-fuzzy progressive transductive support vector machine (BFPTSVM) algorithm by combining the proposed notation of bi-fuzzy memberships for the temporary labeled sample appeared in progressive learning process and the sample-pruning strategy, which decreases the computation complexity and store memory of algorithm. Simulation experiments show that the BFPTSVM algorithm derives better classification performance and converges rapidly with better stability compared to the other learning algorithms.  相似文献   

19.
基于梯度算法的支持向量机参数优化方法   总被引:7,自引:0,他引:7  
刘昌平  范明钰  王光卫  马素丽 《控制与决策》2008,23(11):1291-1295,1300
首先介绍最近出现的参数优化方法,概括了高效率的参数优化算法应具备的若干特点.然后提出了一种新的支持向量机参数优化方法.该方法先在局域内用混沌优化搜索局域最优点,再将此最优点作为梯度方向,通过改变局域范围跳出局部寻优区域.该方法降低了对性能函数连续且可微的要求,收敛速度快,最终优化解与支持向量机的参数初始值无关.最后,通过仿真实验表明了该方法具有更高的分类和回归准确率.  相似文献   

20.
This paper aims at automatic classification of power quality events using Wavelet Packet Transform (WPT) and Support Vector Machines (SVM). The features of the disturbance signals are extracted using WPT and given to the SVM for effective classification. Recent literature dealing with power quality establishes that support vector machine methods generally outperform traditional statistical and neural methods in classification problems involving power disturbance signals. However, the two vital issues namely the determination of the most appropriate feature subset and the model selection, if suitably addressed, could pave way for further improvement of their performances in terms of classification accuracy and computation time. This paper addresses these issues through a classification system using two optimization techniques, the genetic algorithms and simulated annealing. This system detects the best discriminative features and estimates the best SVM kernel parameters in a fully automatic way. Effectiveness of the proposed detection method is shown in comparison with the conventional parameter optimization methods discussed in literature like grid search method, neural classifiers like Probabilistic Neural Network (PNN), fuzzy k-nearest neighbor classifier (FkNN) and hence proved that the proposed method is reliable as it produces consistently better results.  相似文献   

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