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21.
Abstract

The World Wide Web offers a large and ever-expanding number of resources in the fields of psychology and sociology. Growth of the Web has been so fast that it has been difficult to keep track of all the new resources that are rapidly becoming available. With so many new Web sites cropping up, there is a growing need to sort through these resources and determine which sites are the most valuable for research in these subject areas. This study first discusses some criteria for assessing the quality of Web sites, and then applies these criteria to the Web sites currently available in an effort to determine which sites are the best for these two fields.  相似文献   
22.
Abstract

With the explosion of the World Wide Web, numerous search engines have proliferated online, claiming to be the best, fastest, or most accurate. Though each product is slightly different from the others in its presentation and search architecture, what all are providing is keyword searching of the Web's millions of pages. However, there are circumstances, just like in a library catalog, where an individual may want to perform a known-item search rather than a keyword search. The purpose of this paper was to discover whether known-item searches are possible with some of the Web's most popular search engines, and if the results retrieved using such a search would be satisfactory to a user. The author tested and compared four major Web search engines, using the most sophisticated search techniques available. Thirty-nine sites were selected and searched by title, and ranked according to the relevance and order of the displayed results.  相似文献   
23.
ABSTRACT

Many libraries recognize the need to create Web sites accessible to users with disabilities, as legislated in U.S. Code Section 508, but Section 508 compliance defines a minimum legal level of accessibility. The same technology that can make a Web site available to users with disabilities can also make the site available to users with wireless devices, such as PDAs and cell phones, with Internet access. To bring about “maximum accessibility,” library Web designers need to implement Web standards. This article argues the place to begin implementing these standards is with an accessibility statement which serves as both a contract and a navigational aid.  相似文献   
24.
Abstract   A field experiment compares the effectiveness and satisfaction associated with technology-assisted learning with that of face-to-face learning. The empirical evidence suggests that technology-assisted learning effectiveness depends on the target knowledge category. Building on Kolb's experiential learning model, we show that technology-assisted learning improves students' acquisition of knowledge that demands abstract conceptualization and reflective observation but adversely affects their ability to obtain knowledge that requires concrete experience. Technology-assisted learning better supports vocabulary learning than face-to-face learning but is comparatively less effective in developing listening comprehension skills. In addition, according to empirical tests, perceived ease of learning and learning community support significantly predict both perceived learning effectiveness and learning satisfaction. Overall, the results support our hypotheses and research model and suggest instructors should consider the target knowledge when considering technology-assisted learning options or designing a Web-based course. In addition, a supportive learning community can make technology-assisted learning easier for students and increase their learning satisfaction.  相似文献   
25.
为了有效定位校园网格中大量不同属性的动态服务,提出一种校园网格服务发现机制。以小世界模型为理论依据组建虚拟组织(VO),构建普通节点-域-VO的3层体系结构模型,基于该模型提出IS-Gossip算法。最上层在VO之间、中间层在VO内各域间分别用IS-Gossip算法进行分布式查找,最下层在域内进行集中式查找。算法分析表明,该机制提高了服务发现的可扩展性和查询效率。  相似文献   
26.
A model is built of semantic triangle characterized by its universal nature: it is suitable not only for the elements of the real world but also for any elements of the Universe. Various possibilities of the development of the given model are shown, including a dialectic triangle.  相似文献   
27.
This paper presents a detailed characterisation of user behaviour for a series of interactive video experiments over a 12 month period, in which we served popular sporting and musical content. In addition to generic VCR-like features, our custom-built video-on-demand application provides advanced interactivity features such as bookmarking. The dramatic impact of such functionality on how users consume content is studied and analysed. We discuss in detail how this user behaviour can be exploited by content distributors to improve user experience. Specifically, we study how simple dynamic bookmark placement and interactivity-aware content pre-fetching and replication can reduce the impact of highly interactive media on CDN performance.  相似文献   
28.
为减少Pub/Sub系统中遍历广播的负载,基于社会学行为的小世界架构,提出了一种基于朋友圈的路由,给出了朋友圈划分算法以及基于朋友圈的Pub/Sub系统遍历算法,以限制消息在确定范围内传播,降低消息遍历的时间和广播开销。仿真实验表明,所提出的方法与Pub/Sub系统中传统的Gossip及洪泛法相比较,可加快消息的传播速度,降低网络开销。  相似文献   
29.
Web站点的超链结构挖掘   总被引:11,自引:0,他引:11  
WWW是一个由成千上万个分布在世界各地的Web站点组成的全球信息系统,每个Web站点又是一个由许多Web页构成的信息(子)系统。由于一个文档作者可以通过超链把自己的文档与任意一个已知的Web页链接起来,而一个 Web站点上的信息资源又通常是由许多人共同提供的, 因此 Web站点内的超链链接通常是五花八门、各种各样的,它们可以有各种含义和用途。文章分析了WWW系统中超链的使用特征和规律,提出了一个划分超链类型、挖掘站点结构的方法,初步探讨了它在信息收集和查询等方面的应用。  相似文献   
30.
面向ASP模式的塑料注射成型CAE系统   总被引:2,自引:0,他引:2  
随着Internet和电子商务的迅猛发展,一种应用软件的新模式:ASP也逐渐凸现。文章构造了一个面向ASP基于Web的远程塑料注射成型CAE系统,详细介绍了系统的构造方法和关键技术。  相似文献   
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