Taking control of web browsing

Adherence to accessibility guidelines for Web pages does not necessarily guarantee a usable or satisfying Web experience for all persons with disabilities. The needs of many of these individuals fall outside the guidelines for accessible content that most Web authors take into consideration. Many of these users wish, for example, that they simply could ‘enlarge’ what is on a Web page. They also express the wish that pages would be ‘less confusing’. To meet these needs, Web browsers and various software applications provide for a variety of ways in which page presentations can be altered. The effects of these alterations often have unexpected consequences. Some designs accommodate these alterations better than others. This article discusses one such application that allows users to control features of Web page presentation and explores design features that facilitate such control.     

Accessing Egypt: making myths and producing web sites in cyber-Cairo

From an anthropological viewpoint, “accessibility” is not so much a technological and design project as it is a cultural construction, a cognitive schema through which graphic designers and technologists imagine audiences and create appropriate graphic designs that will be “accessible” to that audience. The ethnographer's task is the specification of key actors, institutions and discourses active in the making and remaking of accessibility in a given context. In this article, we examine how Egyptian Web producers at the turn of millennium (1999–2001) sought to design Web portals that would allow the “typical” Egyptian to easily access the World Wide Web. We argue, first, that Egyptian Web producers are deeply influenced by national and international discourses that frame IT as a national mission for socioeconomic development. Second, we found that in the absence of clear definitions of the Web audience, Web producers imagined a “typical” Egyptian that contradicted their own experiences of users of the Web. Finally, we found that Egyptian Web producers largely borrowed pre-existing models, using design elements to “inflect” their sites with an Egyptian motif. However, the conceptual models of access and related design strategies created by Egyptian Web producers were out of touch with Egyptian social realities, contributing to a collapse of most Web portal projects.     

基于Web增强现实的高拱坝仓面施工可视化仿真研究

针对现有的高拱坝施工仿真将浇筑坝块作为最小单元进行仿真研究,忽略了浇筑坝块仓面内部胚层间施工过程的仿真,同时仿真结果的可视化手段与现场割裂,无法在任意场景结合现场实际画面进行结果分析和方案安排的问题,提出基于Web增强现实的高拱坝仓面施工可视化仿真方法。该方法主要包括两个方面:(1)对高拱坝仓面施工过程进行分析,构建高拱坝仓面施工精细仿真模型,并通过仿真计算获得仓面施工各个工序的施工历时;(2)采用Web增强现实技术将设计信息及仿真成果注册至施工现场图像,实现了信息在真实仓面上的直观展示,并实现Web浏览器跨平台的交互分析。结合实际工程开展了研究,结果表明,该方法实现了高拱坝施工进度的精细仿真并提高了可视化水平,施工管理人员可以便捷地结合现场实际情况对施工进度进行分析管理,从而保证大坝按时竣工。     

基于主题深度搜索的数学领域教育平台研究

论文综合利用主题搜索技术、深网信息集成技术和Wiki技术,设计并实现了一个面向数学领域的教育平台.此平台是一个集数学资源共享和用户交流的开放平台,用户在此平台可以利用数学Wiki添加、编辑、评论数学领域信息,提升自主学习能力,实现广泛交流.同时,还能利用数学搜索引擎搜索到专业的数学知识,定制URL检索,扩大检索范围,提高了平台的个性化服务水平及搜索的准确率.实验结果表明,文中基于SVM分类算法的数学主题网页分类器具有较高的准确率和召回率.     

An automatic subdigraph renovation plan for failure recovery of composite semantic Web services

A Web service-based system never fulfills a user＇s goal unless a failure recovery approach exists. It is inevitable that several Web services may either perish or fail before or during transactions. The completion of a composite process relies on the smooth execution of all constituent Web services. A mediator acts as an intermediary between providers and consumers to monitor the execution of these services. If a service fails, the mediator has to recover the whole composite process or else jeopardize achieving the intended goals. The atomic replacement of a perished Web service usually does not apply because the process of locating a matched Web service is unreliable. Even the system cannot depend on the replacement of the dead service with a com- posite service. In this paper, we propose an automatic renova- tion plan for failure recovery of composite semantic services based on an approach of subdigraph replacement. A replacement subdigraph is posed in lieu of an original subdigraph, which includes the failed service. The replacement is done in two separate phases, ofltine and online, to make the recovery faster. The ofitine phase foresees all possible subdigraphs, pre-calculates them, and ranks several possible replacements. The online phase compensates the unwanted effects and executes the replacement subdigraph in lieu of the original subdigraph. We have evaluated our approach during an experiment and have found that we could recover more than half of the simulated failures. These achievements show a significant improvement compared to current approaches     

基于网页抓取分析和统计压缩模型的垃圾邮件过滤系统研究

垃圾邮件过滤是当前计算机领域的热点问题。文章针对目前网页抓取分析技术不能深入分析网页内容的缺点,提出了一种优化的网页抓取分析技术,能够对网页提取一些更为深入的特征,并以此为基础,完成了基于网页抓取分析和统计压缩模型的垃圾邮件过滤系统的设计与实现。文章创新地提取出5种新的特征,实验结果表明,这些特征对于增高TPR(True Positive Rate,真正类率),降低FPR(False Positive Rate,负正类率),提升垃圾邮件过滤的效率和准确性具有显著作用。     

基于H.264的嵌入式Web网络视频监控系统设计

针对传统的视频压缩技术不适合在恶劣的网络环境下应用的问题,提出了一种基于H.264的远程视频监控系统的设计方案。该系统将嵌入式技术、网络技术和视频编码技术结合在一起,嵌入式系统中的摄像头采集到的视频信号经H.264标准编码压缩后,通过系统内置的Web服务器实时地传递给远程监控端,从而实现了远程监控端的浏览器与嵌入式Web服务器之间的互联通信。测试结果表明,该系统的视频压缩率高、图像清晰、实时性强。     

Apache Web服务器中基于LTI模型的多服务类别比例延迟控制

通过系统辨识建立了Apache Web服务器的线性时不变(LTI>模型,用于描述两类Web客户连接的连接延迟比与服务线程比间的关系,并针对此L"I'I模型,设计了一个控制器。此控制器通过动态分配服务于不同类别连接的服务线程的数量,可实现Wcb服务器端的比例延迟保证,并进一步将此区分服务的控制模型扩展到了面向多个连接类别,通过多个控制器实现了相部两个客户连接类别的比例延迟保证。仿真表明,即使过载状态下并发客户连接的数目急剧变化,闭环系统中的Wcb服务器也能为多个客户连接类别提供比例延迟保证。     

一种面向语义Web服务的语义程序变换方法

语义程序变换是面向语义Web服务的软件设计方法的基础,语义程序只有通过程序变换后才能被运行环境执行和调用,然而目前还缺乏有效的语义程序变换方法。针对这一问题,基于语义编程语言SPL,提出了一种面向语义Web服务的语义程序变换方法。该方法通过对语义数据类型、语义规则、语义服务和语义流程等语义信息的有效变换,不仅提高了面向服务的程序设计的灵活性和健壮性,而且有助于提高业务流程的柔性和重用性。