黎曼核局部线性编码

最近的研究表明:在许多计算机视觉任务中,将对称正定矩阵表示为黎曼流形上的点能够获得更好的识别性能.然而,已有大多数算法仅由切空间局部逼近黎曼流形,不能有效地刻画样本分布.受核方法的启发,提出了一种新的黎曼核局部线性编码方法,并成功地应用于视觉分类问题.首先,借助于最近所提出的黎曼核,把对称正定矩阵映射到再生核希尔伯特空间中,通过局部线性编码理论建立稀疏编码和黎曼字典学习数学模型;其次,结合凸优化方法,给出了黎曼核局部线性编码的字典学习算法;最后,构造一个迭代更新算法优化目标函数,并且利用最近邻分类器完成测试样本的鉴别.在3个视觉分类数据集上的实验结果表明,该算法在分类精度上获得了相当大的提升.     

基于协方差描述子和黎曼流形的语音情感识别

提出一种基于协方差描述子和黎曼流形的语音情感识别方法.根据提取的语音声学特征,计算协方差矩阵用于表征语句的情感信息.考虑到非奇异协方差矩阵所构成空间的高维特性,引入一种仿射不变度量使得该空间满足黎曼流形的要求.进而根据微分几何,建立基于黎曼流形的算法架构.实验证明,该方法在语音情感识别中获得较好的识别效果,尤其在噪声环境下能更有效地提高识别准确率.     

基于推广流形学习的高分辨遥感影像目标分类

针对传统的流形学习算法不能对位于黎曼流形上的协方差描述子进行有效降维这一问题，本文提出一种推广的流形学习算法，即基于Log-Euclidean黎曼核的自适应半监督正交局部保持投影（Log-Euclidean Riemannian kernel-based adaptive semi-supervised orthogonal locality preserving projection，LRK-ASOLPP），并将其成功用于高分辨率遥感影像目标分类问题.首先，提取图像每个像素点处的几何结构特征，计算图像特征的协方差描述子；其次，通过采用Log-Euclidean黎曼核将协方差描述子投影到再生核Hilbert空间；然后，基于流形学习理论，建立黎曼流形上半监督正交局部保持投影算法模型，利用交替迭代更新算法对目标函数进行优化求解，同时获得相似性权矩阵和低维投影矩阵；最后，利用求得的低维投影矩阵计算测试样本的低维投影，并用K—近邻、支持向量机（Support victor machine，SVM）等分类器对其进行分类.三个高分辨率遥感影像数据集上的实验结果说明了该算法的有效性与可行性.     

黎曼流形框架上半监督判别分析

针对传统黎曼流形上判别分析算法仅考虑了带标签数据统计信息,忽略了无标签数据的问题,基于图正则化思想,提出一个新颖的基于黎曼流形框架上半监督判别分析算法,并将其应用于视觉分类任务中.该算法将非奇异协方差矩阵表示为黎曼流形上的点,引入JBLD(Jensen-Bregman LogDet divergence)度量黎曼流形上点与点之间相似性测度.首先将数据点映射到黎曼切空间中,获得数据向量化表示;其次采用有标签数据和无标签数据构建近邻图刻画黎曼切空间局部几何结构,使其作为正则化项添加到费舍尔测地线判别分析目标函数中;最后最小化目标函数获取最优变换矩阵,并在变换黎曼流形中进行分类.在3个视觉分类数据集上实验结果表明,文中算法在分类精度上获得了相当大的提升.     

基于流形学习和SVM的Web文档分类算法

为解决Web文档分类问题,提出一种基于流形学习和SVM的Web文档分类算法。该算法利用流形学习算法LPP对训练集中的高维Web文档空间进行非线性降维,从中找出隐藏在高维观测数据中有意义的低维结构,在降维后的低维特征空间中利用乘性更新规则的优化SVM进行分类预测。实验结果表明该算法以较少的运行时间获得更高的分类准确率。     

黎曼流形上的保局投影在图像集匹配中的应用

目的提出了黎曼流形上局部结构特征保持的图像集匹配方法。方法该方法使用协方差矩阵建模图像集合,利用对称正定的非奇异协方差矩阵构成黎曼流形上的子空间,将图像集的匹配转化为流形上的点的匹配问题。通过基于协方差矩阵度量学习的核函数将黎曼流形上的协方差矩阵映射到欧几里德空间。不同于其他方法黎曼流形上的鉴别分析方法,考虑到样本分布的局部几何结构,引入了黎曼流形上局部保持的图像集鉴别分析方法,保持样本分布的局部邻域结构的同时提升样本的可分性。结果在基于图像集合的对象识别任务上测试了本文算法,在ETH80和YouTube Celebrities数据库分别进行了对象识别和人脸识别实验,分别达到91.5%和65.31%的识别率。结论实验结果表明,该方法取得了优于其他图像集匹配算法的效果。     

基于线性判别回归的最近-最远子空间分类鲁棒人脸识别

针对人脸识别中小样本问题导致类依赖子空间不完善而严重影响识别性能的问题,提出一种基于线性判别回归的最近-最远子空间分类算法。首先,基于线性判别回归,利用最近子空间分类器度量测试图像与单一类之间的关系;然后,利用所提出的最远子空间分类器度量测试图像与训练图像之间的关系;最后,结合最近、最远子空间分类器,利用类依赖子空间的不同特性完成人脸的分类识别。在三个公开的人脸数据库ORL、AR及扩展Yale B上的实验验证了该算法的有效性。实验结果表明,相比其他几种分类算法,该算法取得了更好的识别效果。     

核仿射子空间最近点分类算法

受支持向量机的几何解释和最近点问题启发,提出一种新型的模式分类算法——核仿射子空间最近点分类算法。该算法在核空间中,将支持向量机几何模型中的最近点搜索区域由2类训练特征集凸包推广到2类特征样本各自生成的仿射子空间,以仿射子空间作为特征样本分布的粗略估计,通过仿射子空间中的最近的2个点构造平分仿射子空间间隔的最优分类超平面。该算法在ORL人脸识别数据库上的比较实验中取得了较好的识别效果。     

仿射子空间最近点分类算法

为了取得更好的识别效果,受支持向量机的几何解释和最近点问题启发,提出了一种新的模式分类算法——仿射子空间最近点算法。该算法是将支持向量机最近点法的最近点搜索区域由两类训练集凸包推广到两类训练样本各自张成的仿射子空间,并以仿射子空间作为样本分布的粗略估计,通过仿射子空间中的最近点对来构造平分仿射子空间间隔的最优分类超平面。该算法在ORL人脸识别数据库上进行的比较实验中取得了较好的识别效果,从而证实了该方法的可行性和有效性。     

基于子空间流形的图像集识别方法

近年来,基于黎曼流形将图像集在线性子空间中进行表征的图像集识别方法已经被证实有良好的效果,针对该领域存在的图像线性子空间大多高维所导致现有黎曼流形的图像集识别方法存在计算成本高、适用性有限的问题,提出一种基于子空间流形的图像集识别方法。首先,从线性子空间的几何结构出发,利用Grassmann流形对线性子空间进行建模,得到基于Grassmann流形的联合黎曼度量。然后,通过该联合黎曼度量,从高维的Grassmann流形中学习到一个低维的Grassmann流形。最后,对通过学习得到的低维流形上的图像集数据进行图像集识别。实验结果表明,在ETH-80数据集上该方法的识别准确率比投影度量学习（PML）和图嵌入Grassmann判别分析（GGDA）都分别提升了2.5个百分点。证明了在通过提出的度量与方法学习到的低维流形上,图像集数据具有更好的分类结构,从而降低图像集识别计算成本,扩大适用范围,提升识别准确率。     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

法律信息库系统

本文分析了法律数据库的结构和特点，介绍了采用面向对象设计方法和超文本数据库技术开发和实现法律信息库系统将作为重要网络资源之一为不同用户进行法律咨询服务。     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

International Journal of Automation and Computing Table of Contents

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Information for authors

正SCIENCE CHINA Information Sciences(Sci China Inf Sci),cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press,is committed to publishing highquality,original results of both basic and applied research in all areas of information sciences,including computer science and technology;systems science,control science and engineering(published in Issues with odd numbers);information and communication engineering;electronic science and technology(published in Issues with even numbers).Sci China Inf Sci is published monthly in both print and electronic forms.It is indexed by Academic OneFile,Astrophysics Data System(ADS),CSA,Cabells,Current Contents/Engineering,Computing and Technology,DBLP,Digital Mathematics Registry,Earthquake Engineering Abstracts,Engineering Index,Engineered Materials Abstracts,Gale,Google,INSPEC,Journal Citation Reports/Science Edition,Mathematical Reviews,OCLC,ProQuest,SCOPUS,Science Citation Index Expanded,Summon by Serial Solutions,VINITI,Zentralblatt MATH.     

Erratum to: Fast global kernel fuzzy c-means clustering algorithm for consonant/vowel segmentation of speech signal

正Erratum to:J Zhejiang Univ-Sci C(ComputElectron)2014 15(7):551-563doi:10.1631/jzus.C1300320The original version of this article unfortunately contained mistakes.Algorithm 6 should be as follows:Algorithm 6 FGKFCM-F clustering Input:(1)X={x_1,x_2,…,x_N},,x_iR~d,i=1,2,…,N,the dataset;(2)C,1C≤N,the number of clusters;(3)ε0,the stopping criterion;     

Journal of Zhejiang University-SCIENCE C (Computers & Electronics) Total contents

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A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.