XML相关语言解析

本文主要介绍xML相关语言,包括定义语言DTD和XML Schema、样式表语言XSL、样式表转换语言XSLT、文档格式化对象XML-FO、路径语言XPath链接语言XLink、指针语言XPointer、查询语言XQuery和可扩展的超文本标记语言XHTML的技术内涵,论述这些语言的实现模式、功能、以及相互之间的联系,同时还介绍这些语言的标准化状况.     

对XPath，XLink和XPointer的分析研究

XML是针对网络应用的一项新技术。当越来越多的信息存为XML文档时,就需要构造一种方式,通过接口获取信息。这就需要一种方法来确定文档各个部分之间的关系,以及访问一个与其他资源有关的文档的内部各部分。XPath,XLink和XPointer这3种语言都可以用来访问数据。其中,XPointer用来确定文档个别部分的位置,XPath与XSLT和XPointer一起使用来对XML文档各部分进行定位,而XLink则用来与XML文档链接。     

XML的标准规范

本文首先介绍了XML的结构和特点,以及XML的相关技术规范标准,然后结合XML和数据库的优缺点,讨论了基于XML的数据库中间件技术.     

Hypertext Access and the New Oxford English Dictionary

While hypertext access to the New Oxford English Dictionary would seem to be potentially beneficial, the conversion of such a text to a hypertext document and the generation of semantic links may not be feasible. Rather than attempting either the conversion of the text or the designation and storage of specific hypertext links, a prototype frontend called READER has been developed that provides hypertext access to the Dictionary. The emphasis in this work has been to provide the user with the browsing approach typical of hypertext rather than the more traditional query-oriented approach to accessing full-texts. The prototype is based on a dynamic hypertext model which facilitates browsing through the dynamic instantiation of implicit links existing in the text of the Dictionary.     

Open hypermedia as user controlled meta data for the Web

This paper introduces an approach to utilise open hypermedia structures such as links, annotations, collections and guided tours as meta data for Web resources. The paper introduces an XML based data format, called Open Hypermedia Interchange Format, OHIF, for such hypermedia structures. OHIF resembles XLink with respect to its representation of out-of-line links, but it goes beyond XLink with a more rich set of structuring mechanisms, including e.g. composites. Moreover OHIF includes an addressing mechanisms (LocSpecs) that goes beyond XPointer and URL in its ability to locate non-XML data segments. By means of the Webvise system, OHIF structures can be authored, imposed on Web pages, and finally linked on the Web as any ordinary Web resource. Following a link to an OHIF file automatically invokes a Webvise download of the meta data structures and the annotated Web content will be displayed in the browser. Moreover, the Webvise system provides support for users to create, manipulate, and share the OHIF structures together with custom made Web pages and MS Office 2000 documents on WebDAV servers. These Webvise facilities goes beyond earlier open hypermedia systems in that it now allows fully distributed open hypermedia linking between Web pages and WebDAV aware desktop applications. The paper describes the OHIF format and demonstrates how the Webvise system handles OHIF. Finally, it argues for better support for handling user controlled meta data, e.g. support for linking in non-XML data, integration of external linking in the Web infrastructure, and collaboration support for external structures and meta-data.