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Study On Cartographic Portrayal Mechanism Of Geographic Information And Its Design And Implementation Based On XML Technology

Posted on:2006-09-15Degree:DoctorType:Dissertation
Country:ChinaCandidate:Z C YinFull Text:PDF
GTID:1100360182465668Subject:Cartography and Geographic Information Engineering
Abstract/Summary:PDF Full Text Request
The formation of map and its following development related closely to our social demands. Meanwhile, contents and forms of map, and the approach to design and produce it also have developed with the progress in scientific technology. Furthermore, as for modern cartography, its academic achievements and current development level can reflect directly or indirectly the extent and depth of mapping (Liao, 2003). However, the development of cartographic theories and methods lags far behind the technical evolutions (Meng, 2003)Many cartographic production organizations have a strategy of building a central geographic database, and from that deriving a range of cartographic products. However, the cartographic presentation tools and symbolization mechanisms available in the existed GIS software that is used to build and maintain the geographic database, have not provided the cartographic quality or the human freedom to produce directly the desired cartographic outputs (Paul, 2004). This dissertation creates a cartographic portrayal model, which revolves around cartographic data, and which includes override mechanisms to empower the human cartographer to modify individual features and representation parts without affecting the master geographic data to implement high-quality cartography, and which avoids unnecessary data duplication.The mapping process, which is driven by geographic database, can be conceived of as a series of information transformations (Aileen, 2005). When applications of geographical information turn to the internet, many problems come up. At this time, web services dealing with geographic information are not fully standardized even if efforts are undertaken by ISO and OpenGIS Consortium (OGC) to enact specification for their semantic interoperability (Badard, 2003). In the dissertation, the cartographic portrayal model is represented with the Extensible Markup Language, including XML, GML, XSL, SVG, which used to describe the geographic data, map-making data, and cartographic data, to implement open representation for the data -to-map transformation.The main research work in the dissertation is divided into parts as follows:1. On the one hand, an overview of cartographic portrayal of geographic information is made, and analyses are also given to methodologies for visualization of spatial data, basic theories of digital cartography and XML based technology for visualization, and finally it is pointed out that XML technology is an important technological basis, enabling cartographic portrayal to develop in web applications. On the other hand, based on analyses of existing methodologies for cartographic portrayal such as GIS visualization, electronic map, geographic information portrayal, WMS, SLD, a cartographic data model is constructed and a cartographic portrayal mechanism is put forward based on this model, thus providing theoretic basis for both distributed handling of the portrayal, and sharing and extending of cartographic data,2. Current models for the portrayal can just visualize geographic information with map symbols, but neglect the functionality of editing maps, which makes it difficult for maps to express spatial information effectively. Therefore, considering integration of the portrayalmechanism and traditional mapping, interactive map editing should be an important part of the cartographic portrayal mechanism. Meanwhile, both a spatiotemporal model and a scale model for cartographic data are proposed, based on features of dynamic map and multi-scale map of new type.3. Following the current trend to apply the portrayal of geographic information and map service to web and distributed handling, a cartographic portrayal model is proposed, which takes XML and its derived proprietary markup language such as GML, SVG, XSL to express and implement the cartographic portrayal of geographic information. Furthermore, a methodology for implementing portrayal rules is put forward based on XSL, after analysis of features of the XSL language, and also is employed in the detailed design of the portrayal rules in the specifications for cartographic symbols; a mapping markup language based on XML is primarily created by taking the structure and content of cartographic data and features of XML as a meta markup language into account; a description model for map symbols is built based on SVG's advantages to describe two-dimensional graphics, and the design of map symbols is also implemented based on SVG4. Guided by our created cartographic portrayal model based fully on XML, an experiment is made to test the transformation from GML data based on XSLT to the cartographic data; map symbols library based on SVG is created to symbolize the cartographic data; implementation of mapping functionalities such as editing map symbols is basically achieved using scripts.
Keywords/Search Tags:sharing, specifications for cartographic symbols, geographic information portrayal, extensible Markup Language, Scalable Vector Graphics
PDF Full Text Request
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