A Study On Data Dictionary For Map Symbol Based On The Model Of Map Language Structure

Digital Line Graphs is not only the most important data of Spatial Data Infrastructure,but also the important data source in cartography. Using the data of DLG to make topographicmap is the important content in the integration of map and geographic information. It refers tothe map expression and the basic problems about standards, theories, methods and dataapplications. Map language is one of the theories of cartography. It can be used as the basictheory of map expression and standard problem. What is the key problem to study the maplanguage is to give a model of map language structure.The semiotics is closely connected with the linguistics. They provide the basic theoriesand methods for the research of map language. Starting with how to use DLG to make map,this paper studies map word in map language based on the point of Saussure who is a linguistthat the word has two sides of signifier and to be signified. Making the word as the smallestunite of graphic symbols, the paper gives a specific model of map language structure,including map word, map phrase, map sentence and map text. Semantics and grammar aretwo important parts in understanding map language. Meanwhile, the understanding of maplanguage is a process of spatial cognition. The paper proposes the spatial homogeneity of mapgrammar in map sentence based on the theories of the universal grammar of human’s innerlanguage which had been studied by the linguist Noam Chomsky, and human’s visualcognition process. Also it proves that the grammatical feature is able to meet the distributionfeature of symbols in the two-dimensional map. How to deal with the mapping relationship isa important process to achieve the mapping results that meet the standards of the specification.In map language, the rhetoric is corresponding to the mapping relationship. It is based on thetheory of "zero" in semiotics, reflecting the layout and expression of the rhetoric, and studiedthe use of rhetoric in dealing with the mapping relationships when some situations such asoccupying, covering and so on occur in map compilation. In the study of standards about theintegration of map and DLG, based on the model of map language structure, synthesize thecharacteristics of the data dictionary for fundamental geographic information features and thecartographic symbols for national fundamental scale maps, the author proposes and compiles the data dictionary for cartographic symbols, describes the map words, word formation rulesand sentence parameters in the process of map expression. This will provide an importanttheoretical support to the problem of standardization.This paper gives a model of map language structure from the perspective of cartography.It has the characteristics of symbol, system and hierarchy. The data dictionary that proposedand compiled based on this model has proved that the model is precise in theory and practicalin production, and can be used as the basic in the problem of standardization about theintegration of DLG and map.