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1.
For the task of visual-based automatic product image classification for e-commerce, this paper constructs a set of support vector machine (SVM) classifiers with different model representations. Each base SVM classifier is trained with either different types of features or different spatial levels. The probability outputs of these SVM classifiers are concatenated into feature vectors for training another SVM classifier with a Gaussian radial basis function (RBF) kernel. This scheme achieves state-of-the-art average accuracy of 86.9% for product image classification on the public product dataset PI 100.  相似文献   

2.
The rapid development of the Internet brings a variety of original information including text information, audio information, etc. However, it is difficult to find the most useful knowledge rapidly and accurately because of its huge number. Automatic text classification technology based on machine learning can classify a large number of natural language documents into the corresponding subject categories according to its correct semantics. It is helpful to grasp the text information directly. By learning from a set of hand-labeled documents, we obtain the traditional supervised classifier for text categorization (TC). However, labeling all data by human is labor intensive and time consuming. To solve this problem, some scholars proposed a semi-supervised learning method to train classifier, but it is unfeasible for various kinds and great number of Web data since it still needs a part of hand-labeled data. In 2012, Li et al. invented a fully automatic categorization approach for text (FACT) based on supervised learning, where no manual labeling efforts are required. But automatically labeling all data can bring noise into experiment and cause the fact that the result cannot meet the accuracy requirement. We put forward a new idea that part of data with high accuracy can be automatically tagged based on the semantic of category name, then a semi-supervised way is taken to train classifier with both labeled and unlabeled data, and ultimately a precise classification of massive text data can be achieved. The empirical experiments show that the method outperforms the supervised support vector machine (SVM) in terms of both F1 performance and classification accuracy in most cases. It proves the effectiveness of the semi-supervised algorithm in automatic TC.  相似文献   

3.
基于支持向量机理论对出行链活动类型的识别方法进行了研究. 首先对居民出行的时间序列位置信息做数据预处理,提取出行链的出行过程和活动地点信息,并结合地理信息系统(GIS)提取活动的备选类型;然后从出行链和活动的时间和空间因素提取活动类型识别的特征,形成特征向量作为分类器的输入,并建立基于支持向量机的两两分类器,采用分类器投票的方法从备选集中选择活动的类型;最后利用模拟数据和交叉验证的方法对两两分类器进行训练检验,分别从高斯径向机核函数和多层感知器核函数的角度分析活动类型识别率. 结果表明:在两两分类中,高斯径向机核函数的最高识别率为99%,最低识别率为62%;多层感知器核函数的最高识别率为97%,最低识别率为54%.  相似文献   

4.
This paper focuses on support vector machine (SVM) based trip chain's activity type recognition. First, the time-series location information of person trip is processed to obtain the trip chain elements including moving processes and activities, and the activity options are extracted from the geographic information system (GIS) around the activity sites. Second, the activity features are drawn from spatio-temporal factors of trip chain to serve as the input feature vector of classifier. A SVM based one-to-one classifier is established and the method of one-to-one classifier voting is adopted to decide the most likely activity type from the activity options. Finally, the classifiers are trained with simulation data based on the Gaussian radial basis (RBF) kernel function and the multilayer perception (MLP) kernel function respectively, and then examined by cross validation. The result shows that in the one-to-one classifying scheme, the highest and lowest right recognition rate with RBF are 99% and 62%, and the corresponding results with MLP are 97% and 54%, respectively.  相似文献   

5.
提出一种新的基于半监督的SVM—KNN分类方法,当可用的训练样本较少时,使用SVM进行分类,不能得到准确的分类边界,本文采用半监督学习策略从大量未标记样本中提取边界向量来改善SVM-KNN分类器的引进不仅扩充了SVM的训练样本数目,而且优化了迭代过程中训练样本的标记质量,可不断修复SVM的分类边界.实验结果表明,所提出的方法能提高SVM算法的分类精度,通过调整参数能够获得更好的分类效果,同时也减小了标记大量未标记样本的代价.  相似文献   

6.
基于统计学习的音频分类具有理论基础坚实,实现机制简单等特点受到广泛关注并被很多音频分类系统所采用。本文对核Logistic回归算法(KLR)进行了深入分析,提出基于KLR的音频分类器设计方法,应用其解决同类型的乐器音乐分类问题。结合所采集的小提琴中提琴和大提琴的音乐信号样本进行了分类仿真试验,并与传统的Logistic回归(LR)和支持向量机(SVM)进行对比。结果表明,核Logistic回归模型具有较为优越的分类性能和非线性处理能力。  相似文献   

7.
铁氧体磁瓦表面典型缺陷检测方法   总被引:2,自引:0,他引:2  
为解决人工磁瓦表面缺陷检测质量不稳定的问题,提出了一种自动检测磁瓦表面缺陷的方法.首先利用磁瓦轮廓长度、面积等几何特征及轮廓匹配的相似度作为特征向量,采用支持向量机进行初次分类;然后再利用对凸凹缺陷的分析,得到缺陷数量和面积作为特征向量,采用最小均方误差分类器进行二次分类;最后对上述2步结果做与运算,得出最终判断.实验表明本方法可以达到正确识别率约为91.80%,错误接受率约为0.75%,正确拒绝率约为14.00%.   相似文献   

8.
提出了一种利用多SVM分类器对高速公路中的复杂交通信息进行有效融合的异常事件检测方法.首先,将初始训练集划分为互不重叠的子集,为每个子集训练分类器.给定一个输入向量,利用分类器求得其所属的类别标签,并计算出该向量对特定簇的隶属度.其次,利用概率方法将多SVM分类器分类结果进行融合,得到最终分类结果.接下来,将“车流量”、“行车速度”、“道路占用率”、“相邻监测站的车流量差值”、“速度差值”以及“道路占用率差值”等交通参数表示为特征向量,分别输入到经过训练的SVM分类器,并将多SVM分类器融合后的分类结果作为判别异常事件的依据.最后,从5个具有代表性的高速公路路段采集到的交通数据构造实验数据集.实验结果表明,对比单一SVM和LS-SVM,文章提出的基于多SVM分类器融合的高速公路异常事件检测方法可以有效提高高速公路异常事件检测的准确性和可靠性,弥补了仅使用单一交通参数进行异常事件检测的不足.  相似文献   

9.
铁建企业项目具有规模大、周期长、技术性强等特征,使工程投标项目评估更复杂、决策难度更大.本文将盈利与竞争力提升作为铁路建筑企业项目投标决策的直接影响因素,提出了基于波士顿矩阵原理的项目分类策略,从项目因素、环境因素、自身因素和业主因素等4个方面出发构建了项目类别判定的粗糙集模型,并利用SVM(支持向量机)对已建立的粗糙集模型进行改进,证明改进模型的计算结果更加准确.根据模型分析结果对项目投标提出了若干有意义的建议,为铁路建筑企业项目投标决策提供参考.  相似文献   

10.
基于智能手机采集的居民出行轨迹信息,分析了不同出行方式的特征,利用支 持向量机进行了出行方式识别研究.首先探讨了利用手机软件所能检测和记录的参数,进 而从出行轨迹和特征参数两个方面对出行方式特征进行了分析,探讨了不同出行方式两 两可分的关键变量,提取用于识别不同出行方式的特征向量,最后建立了径向基核函数 支持向量机(SVM)分类器.利用从大连市出行轨迹数据获取的出行方式样本,训练了该 支持向量机,并且以决策树、BP 神经网络为对照.结果表明,SVM 识别精确度为 89.6%,BP 神经网络为 85.5%,决策树为 77.3%,SVM 具有更好的识别性能.  相似文献   

11.
Web page classification is an important application in many fields of Internet information retrieval, such as providing directory classification and vertical search. Methods based on query log which is a light weight version of Web page classification can avoid Web content crawling, making it relatively high in efficiency, but the sparsity of user click data makes it difficult to be used directly for constructing a classifier. To solve this problem, we explore the semantic relations among different queries through word embedding, and propose three improved graph structure classification algorithms. To reflect the semantic relevance between queries, we map the user query into the low-dimensional space according to its query vector in the first step. Then, we calculate the uniform resource locator (URL) vector according to the relationship between the query and URL. Finally, we use the improved label propagation algorithm (LPA) and the bipartite graph expansion algorithm to classify the unlabeled Web pages. Experiments show that our methods make about 20% more increase in F1-value than other Web page classification methods based on query log.  相似文献   

12.
微表情是一种不能自主控制和伪装的面部表情,其与诚信度的关系密切,具有持续时间短且难以识别的特征.为提高计算机自动识别微表情的准确性,提出一种基于差分能量图和中心化Gabor二值模式(centralized Gabor binary patterns,CGBP)的微表情识别方法.该方法首先利用差分法计算微表情序列的能量得到差分能量图,获得人脸面部肌肉相位的变化;其次将Gabor与中心二值模式CBP相结合,得到CGBP算子对能量图进行微表情的特征提取;最后利用ELM分类器进行微表情分类识别.在CASME微表情库上的实验结果表明,该方法比LBP-TOP、DTSA3、Gabor、VLBP、CBP-TOP算法更能有效地获得微表情序列的时空纹理特征,平均识别率为86.54%.   相似文献   

13.
Hepatic computed tomography(CT) images with Gabor function were analyzed.Then a threshold-based classification scheme was proposed using Gabor features and proceeded with the retrieval of the hepatic CT images.In our experiments, a batch of hepatic CT images containing several types of CT findings was used and compared with the Zhao's image classification scheme, support vector machines(SVM) scheme and threshold-based scheme.  相似文献   

14.
为监测复杂生产过程的状态,根据多元统计过程控制方法和支持向量机理论,将累积和控制图原理扩展为多变量的形式对过程数据进行预处理,并通过主元分析方法提取复杂生产过程的关键信息,得到有效的小故障数据,进而构建计算正常数据的统计量阀值及故障数据的Hotelling T平方统计值(T2)和平方预测误差值,实现了复杂生产过程的小故障模式检测,并采用支持向量机多分类方法将检测到的故障进行了分类.沥青混合料生产过程的仿真研究表明:在集料均值发生小波动、周期性上升和下降3种小故障模式下,故障检测识别率均达到95%,与主元分析方法相比平均提高了75%;分类准确率达到92.5%,与BP神经网络方法相比提高了19.3%.   相似文献   

15.
基于概率支持向量机方法的人脸识别   总被引:1,自引:0,他引:1  
针对智能会议场景对人脸识别的特殊情况,通过依据检测、跟踪得到头部区域与人脸区域的面积比,选择正面的人脸进行识别,降低了人脸姿态对人脸识别的影响.在分类方法的选择上,采用支持向量机方法,并对支持向量机方法进行了概率建模,分类器输出结果是测试人脸属于每类的概率.实验结果表明:该方法不仅使人脸识别的精度得到了提高,还提供了其属于所在类中的可信程度.  相似文献   

16.
Skin detection has been considered as the principal step in many machine vision systems, such as face detection and adult image filtering. Among all these techniques, skin color is the most welcome cue because of its robustness. However, traditional color-based approaches poorly perform on the classification of skin-like pixels. In this paper, we propose a new skin detection method based on the cascaded adaptive boosting (AdaBoost) classifier, which consists of minimum-risk based Bayesian classifier and models in different color spaces such as HSV (hue-saturation-value), YCgCb (brightness-green-blue) and YCgCr (brightness-green-red). In addition, we have constructed our own database that is larger and more suitable for training and testing on filtering adult images than the Compaq data set. Experimental results show that our method behaves better than the state-of-the-art pixel-based skin detection techniques on processing images with skin-like background.  相似文献   

17.
To improve the detection rate and lower down the false positive rate in intrusion detection system,dimensionality reduction is widely used in the intrusion detection system.For this purpose,a data processing (DP) with support vector machine (SVM) was built.Different from traditionally identifying the redundant data before purging the audit data by expert knowledge or utilizing different kinds of subsets of the available 41-connection attributes to build a classifier,the proposed strategy first removes the attributes whose correlation with another attribute exceeds a threshold,and then classifies two sequence samples as one class while removing either of the two samples whose similarity exceeds a threshold.The results of performance experiments showed that the strategy of DP and SVM is superior to the other existing data reduction strategies (e.g.,audit reduction,rule extraction,and feature selection),and that the detection model based on DP and SVM outperforms those based on data mining,soft computing,and hierarchical principal component analysis neural networks.  相似文献   

18.
提出使用最小二乘支持向量机LS—SVM(Least Squares Support Vector Machines)算法进行乐器音乐分类,从而实现乐器的辩识。在对Ls—sVM理论进行深入探讨的基础上,选择乐器音乐clip作为样本,进行特征提取,提取的特征包括频谱特征,短时自相关系数和MFCC等,然后用最小二乘支持向量机算法进行分类。对古琴、古筝、箜篌和琵琶音乐采取样本进行仿真实验,求得分类准确率和运行时间,同时使用逻辑回归(Logistic Regression)算法进行对比试验,其中最小二乘支持向量机和逻辑回归分类的准确率分别为96.5%和92.5%,且LS—SVM的运行时间比Logist的少。实验结果表明最小二乘支持向量机具有更为优越的分类性能和非线性处理能力,可以推广用于解决其它实际分类问题。  相似文献   

19.
在恶劣天气下路面湿滑状况将发生显著变化,导致驾驶条件恶化,极易引发恶劣的交通事故.为了帮助交通管理部门实时获取路面湿滑状况信息,了解路面附着性能,并以此制定合理的车速控制和交通诱导策略,通过采集道路湿滑图像,利用设计的具体SVM分类器结合3种训练算法对道路湿滑图像进行分类学习训练,并通过训练后的SVM分类器对大量道路湿滑图像进行分类实验,对道路湿滑状态进行分类研究.实验结果表明:(1)寻找合适的核函数,选择合适的参数是使用SVM进行高效分类的一个重要因素;(2)在训练过程中,均方误差(MSE)能反映出分类器实现的正确率,SVM的训练本身的误差决定了分类的正确率,而且训练个数的增多带来了特征空间维数的增加,从而导致计算量的增大.  相似文献   

20.
文中阐述了采用1985年7月4日和8月5日的陆地卫星TM数据对纽约州西里卡县进行农作物自动分类的研究。农作物主要指玉米和小麦。使用监督的最大似然率数字图象分类法。分类结果的精度:玉米为72~91%的正确分类率,小麦为82~88%的正确分类率,同时分类的附加误差很小。文中对如何选择训练数据,以提高分类的精度和可靠性作了研究。  相似文献   

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