最近几年来,地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持,如城市管理、区划、环境整治等等,地理信息成为信息时代重要的组成部分之一; “数字地球”概念的提出,更进一步推动了作为其技术支撑的GIS的发展。 与此同时,一些学者致力于相关的理论研究,如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面,并且这两个方面构成了相互促进的发展过程。
This section provides an overview of other important and interesting W3C activities. WAI defines guidelines on how to make Web content easier for people with disabilities. WAI works towards the goal of “Web accessibility for all” through technology, guidelines, tools, education, research, and development projects. W3C WAI recommendation MathML is an XML standard for describing mathematical symbols. The goal of MathML is to enable mathematics to be provided, accepted, and processed on Web, just as HTML can enable text to achieve. W3C MathML recommendation SVG is a language used to describe two-bit graphics in XML. SVG runs three types of graphic objects: vector graphics shapes, images, andtext. Property settings include transformations, crop paths, alpha masks, filter effects, template objects, and extensibility. W3C SVG 1.1 recommendation W3C SVG 1.2 working draft InkML is a XML data format used to express digital ink data, which is input through an electronic pen or input pen that is part of a multi-channel system. W3C InkML working draft The goal of the W3C internationalization campaign is to recommend and adapt any technologies, agreements, guidelines, and activities within the W3C and with other organizations to make it easier to use W3C technologies globally in different languages, scripts, and cultures. W3C internationalization activities The work of the W3C Voice browser activity is to expand the scope of Web by enabling people to interact with spoken instructions and speech synthesis. Voice Extensible markup language (VoiceXML) Speech synthesis markup language (VoiceXML) Speech recognition grammar specification Voice browser call Control (CCXML) 4.16.1. The Web Accessibility Initiative (WAI) ¶
4.16.2. Mathematical markup language-Mathematical Markup Language (MathML) ¶
4.16.3. Scalable vector graphics-Scalable Vector Graphics (SVG) ¶
4.16.4. Ink markup language-Ink Markup Language (InkML) ¶
4.16.5. Internationalization-Internationalization ¶
4.16.6. Voice browser activity ¶