本文介绍一种基于扩展标记图ETG(Extended Tag Graph)的网页信息抽取与重组新技术,引入了扩展标记图操作和重构概念,提出了作为用户接口的标记查询语言TagSQL。用户通过类标准SQL的语言描述,即可方便地实现对网页信息的灵活抽取和重组...本文介绍一种基于扩展标记图ETG(Extended Tag Graph)的网页信息抽取与重组新技术,引入了扩展标记图操作和重构概念,提出了作为用户接口的标记查询语言TagSQL。用户通过类标准SQL的语言描述,即可方便地实现对网页信息的灵活抽取和重组操作。展开更多
STEP-NC是新发展的数控编程国际标准(ISO 14649),依据该标准生成的数控程序通常采用ISO10303 Part 21物理文件格式。但该格式的数控程序不但不易解释,而且不适合在网上传输。为此,提出了采用可扩展标记语言作为STEP-NC数控程序的文件格...STEP-NC是新发展的数控编程国际标准(ISO 14649),依据该标准生成的数控程序通常采用ISO10303 Part 21物理文件格式。但该格式的数控程序不但不易解释,而且不适合在网上传输。为此,提出了采用可扩展标记语言作为STEP-NC数控程序的文件格式。首先,分析了STEP-NC数据模型核心内容及ISO10303Part 21物理文件格式数控程序的缺点,研究了可扩展标记语言格式STEP-NC数控程序的生成,包括文档结构的选择、EXPRESS向可扩展标记语言的映射等,并将其作为机床控制器的输入。将机床控制器软件划分为3个模块,即可扩展标记语言形式数控程序的解释、微观工艺规划并自动生成刀具路径和控制机床运动的数控指令的生成。重点研究了可扩展标记语言数控程序的解释。展开更多
XML is a promising technology developed in recent years. Due to its superiority in extensibility and flexibility,XML has become the language over the internet. With more and more XML documents produced,the problem exi...XML is a promising technology developed in recent years. Due to its superiority in extensibility and flexibility,XML has become the language over the internet. With more and more XML documents produced,the problem exists to transform them to other documents of various structures. This paper discusses and compares four methods to transform XML documents,then introduces XSLT,a W3C recommendation, by giving examples and outlining a project in brief.展开更多
文摘STEP-NC是新发展的数控编程国际标准(ISO 14649),依据该标准生成的数控程序通常采用ISO10303 Part 21物理文件格式。但该格式的数控程序不但不易解释,而且不适合在网上传输。为此,提出了采用可扩展标记语言作为STEP-NC数控程序的文件格式。首先,分析了STEP-NC数据模型核心内容及ISO10303Part 21物理文件格式数控程序的缺点,研究了可扩展标记语言格式STEP-NC数控程序的生成,包括文档结构的选择、EXPRESS向可扩展标记语言的映射等,并将其作为机床控制器的输入。将机床控制器软件划分为3个模块,即可扩展标记语言形式数控程序的解释、微观工艺规划并自动生成刀具路径和控制机床运动的数控指令的生成。重点研究了可扩展标记语言数控程序的解释。
文摘XML is a promising technology developed in recent years. Due to its superiority in extensibility and flexibility,XML has become the language over the internet. With more and more XML documents produced,the problem exists to transform them to other documents of various structures. This paper discusses and compares four methods to transform XML documents,then introduces XSLT,a W3C recommendation, by giving examples and outlining a project in brief.
