基于SVM的金融类钓鱼网页检测方法

针对金融服务领域面临的严峻信息安全挑战,以及现有钓鱼网页检测方法的不足,提出一种基于支持向量机(support vector machine,SVM)的金融类钓鱼网页检测方法.采用网页渲染去除常见的页面特征伪装,提取统一资源定位符(uniform resource locator,URL)信息特征、页面文本特征、页面表单特征以及页面logo图像特征,构建特征向量训练SVM分类器模型,实现对金融类钓鱼网页的识别.在特征提取过程中,利用适合中文的多模式匹配算法AC_SC(AC suitable for chinese)提高文本匹配效率,并采用加速鲁棒特征(speeded-up robust feature,SURF)算法实现logo图像的特征提取与匹配.多方法实验结果对比表明,该方法针对性更强,能达到99.1％的检测准确率、低于0.86％的误报率.     

基于敏感特征的网络钓鱼网站检测方法

网络钓鱼(phishing)是一种在线欺诈行为,普遍存在于电子商务和电子金融中。将黑白名单方法和异常特征检测方法相结合,针对网络钓鱼网站URL异常和页面身份异常特点提出基于敏感特征的网络钓鱼网站检测方法——PhishDetector。使用黑白名单技术对URL进行拦截,对于名单中不存在的URL,提取其敏感特征,然后使用线性分类器判断该网站是否为网络钓鱼网站。实验结果表明,基于敏感特征的网络钓鱼网站检测方法,提高了网络钓鱼网站检测的正确率,显著降低了误判率。     

基于敏感特征的网络钓鱼网站检测方法

网络钓鱼(phishing)是一种在线欺诈行为,普遍存在于电子商务和电子金融中．将黑白名单方法和异常特征检测方法相结合,针对网络钓鱼网站URL异常和页面身份异常特点提出基于敏感特征的网络钓鱼网站检测方法——PhishDetector．使用黑白名单技术对URL进行拦截,对于名单中不存在的URL,提取其敏感特征,然后使用线性分类器判断该网站是否为网络钓鱼网站．实验结果表明,基于敏感特征的网络钓鱼网站检测方法,提高了网络钓鱼网站检测的正确率,显著降低了误判率．     

基于文本特征分析的钓鱼邮件检测

提出了一种基于邮件文本特征的钓鱼邮件检测方法。首先利用邮件解析器将邮件中非文本部分内容剔除,然后提取邮件剩余部分中存在的网站链接及其他内容,并在此基础上提取10种特征。针对这些特征,利用机器学习方法对其进行训练和预测,将邮件分类为普通邮件和钓鱼邮件。我们改进了以往一些针对网站链接分析的检测方法,并结合钓鱼邮件发展的新趋势,提出了6种新的特征。实验证明,本方法结合了新的钓鱼邮件特征,有效地提高了钓鱼邮件检测的召回率以及精准率,同时误判率有所降低。并且,本方法稍加改进以后就能用于钓鱼网站的检测。     

基于属性降维的钓鱼网站检测方法

随着对钓鱼网站分析刻画的不断完善,使得钓鱼网站检测特征呈现高维化特点。属性维度的增加以及数据量的增长,会造成检测计算复杂度呈几何倍数扩大,导致检测时间复杂度高、占用资源大和检测效率低。针对多属性的钓鱼网站检测,设计了一种基于属性降维的钓鱼网站检测方法。该方法使用信息增益方法对原始数据进行特征选择,筛除可能存在的冗余和噪声数据信息;根据不同属性间的互信息计算属性相关性矩阵,利用属性相关性矩阵作为权值参与加权主成分分析;根据得到的降维后新特征数据通过监督学习算法构建钓鱼网站检测模型。实验表明,该方法可以有效降低原始数据中冗余和噪声属性的干扰,能够有效检测出复杂网络环境中的钓鱼网站,同时具有较高的稳定性。     

基于改进Stacking策略的钓鱼网站检测研究

针对目前大多数钓鱼网站检测技术准确率低、计算资源消耗大和检测不及时等问题,本文提出一种基于改进Stacking策略的钓鱼网站检测方法。该方法将多个分类表现优异的基学习器通过Stacking策略集成为一个高性能模型,并且把该Stacking算法第一级的输入特征与预测结果同时作为第二级的输入特征,充分发挥各模型精度高、速度快等优势,从而进一步提高模型性能。实验结果表明,与传统的机器学习钓鱼网站检测技术相比,在10万级数据集上,此集成学习算法在多个指标上都表现出更好的性能,精确率达到了97.82%,F₁值达到97.54%,可以有效地检测钓鱼网站。     

基于模板检测的违法网站识别方法

为高效识别违法网站,该文提出了一种新方法。从HTTP POST提取特征值,计算网站间相似度,对网站进行聚类并抽取违法网站模板用来识别违法网站。应用图挖掘技术过滤合法网站,提升识别效率。以赌博网站为例,在真实环境中对该方法进行了大规模实验和评估。实验结果表明:该方法检测出赌博网站的精确度为1;与URL、HTML和语义特征相比,HTTP POST特征值的F-Measure最好;应用图挖掘技术可以有效过滤合法网站,提高整个流程运行效率20%。     

网络钓鱼邮件分析系统的设计与实现

随着网络技术的发展,网络犯罪应运而生。网络钓鱼活动日益加剧,网络钓鱼攻击成为Internet上最主要的网络诈骗方式,对网络安全和电子商务的正常运行构成了极大的威胁。通过给用户发送电子邮件,把用户引到精心设计好的钓鱼网站上,实施诈骗活动,是钓鱼者常用的手段。对网络钓鱼邮件的特点进行分析,基于这些特点设计出网络钓鱼邮件分析系统,该系统通过提取邮件的内容,对其进行分析,提取出可疑的URL,从而过滤出具有网络钓鱼特征的邮件,有效屏蔽了网络钓鱼网站。     

基于Logistic回归和XGBoost的钓鱼网站检测方法

为兼顾钓鱼网站检测的速度和准确率,提出一种基于Logistic回归和XGBoost的钓鱼网站检测方法.根据网页的URL提取HTML特征、URL特征和基于TF-IDF的文本向量特征,结合Logistic回归将高维和稀疏的文本特征转换为概率特征.基于以上融合特征,构建了XGBoost分类模型,给出了方法的时间复杂度分析,采集了真实数据作为实验数据集.实验结果表明,Logistic回归方法降低了融合特征的维度,检测速度优于直接融合方法;融合特征方法比单方面特征方法含有更多有效的信息,可供分类器进行学习,检测精度高于单方面特征方法,精确度达到96.67%,召回率为96.6%.     

基于探测查询的Deep Web实体识别

目前,Web上存在很多Deep Web网站,而各个网站的数据表现形式有很大的差别.因此要集成这些网站就需要正确抽取其中的数据,并将其中表示同一实体的数据合并.该文提出了一种基于探测查询的方法来自动完成页面的数据抽取及实体识别工作,该方法通过提交查询可以在提取数据的同时确定实体的各个属性,根据实体的各个属性进行实体识别.实验表明,该方法具有较高的实体识别准确率.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.