地理信息系统概念（The concept of geographic information systems）.doc

地理信息系统概念（The concept of geographic information systems） 1, geographical information system (geographic information system, gis) - a set of computer science, informatics, geography and so on many science as one of the emerging discipline, it is in a computer software and hardware support, using the theory of systems engineering and information science, the connotation of scientific management and comprehensive analysis with space geographic data, in order to provide for to be information for planning, management, decision making and space information system. 2. Compare gis with cad and cac. Cad - computer aided design, the generation, editing and display of rule graphics, independent of external description data. Cac - computer aided mapping, special software for cartographic mapping, lack of spatial analysis ability. Gis -- geographic information system, combining rules graphics and maps, with strong spatial analysis capabilities. 3. Layer: the space information is divided into special topics according to its geometric features and properties. 4. Geographic data collection - field investigation, sampling; Traditional methods of measurement, such as triangulation and triside measurement; Global positioning system (GPS); Modern remote sensing technology; Biotelemetry; Digital photography; The census. 5, information model, the traditional mapping methods, referred to as the information paradigm, which assumes that the map itself is a final product, through the use of symbols, classification, limit the choice of methods such as the exchange of spatial information model. This example is a traditional perspective method, and because of the original and many restrictions, map users cannot easily obtain pre-classified data. In other words, users are limited to processing the final product, and cannot reorganize the data into more effective forms to adapt to changes in the environment or requirements. 6. Analysis paradigm (overall example) -- storing the data of the original