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In the practice of cartography, people always face two kinds of geographic world's models. One is digital landscape
model (DLM), and another is digital cartographic model (DCM). In DLM, geographic feature are expressed by
coordinate, attribute and relationship among them, it is independent from symbols. Reversely, DCM is closely related
with symbols and paper maps which will be published. In this paper I will discuss the design of map database for DCM.
First, this paper introduces characteristics of GIS database and Map database to us, and then elaborates their
relationships and differences.
Second, it represents the contents of map database, which consists of five parts such as spatial location, attributes,
spatial relationship, time, symbol and cartographic expert's knowledge for symbolization control. So we can draw a
conclusion that the map database is an organic combination of GIS database and cartographic expert's knowledge.
Third, this dissertation depicts the implement of map database by an example which is applied in the paper topography
mapmaking and infrastructural geographic information's yield. We design data tables according to geographic feature's
geometry type such as point, line, polygon, complex and annotation. By foreign keys related to dictionary tables we can
divide features into different geography layers (such as vegetation, river, road etc.) and publish layers (such as red point,
black line, green polygon, black annotation etc.). Aiming at different geographic feature possessing of different items of
attributes, we also design a universal method to store feature's attribute data.
Fourth, this dissertation introduces a method using cartographic expert knowledge and experience to control the
process of dynamic map symbolization. The authors think it should formalize the fuzzy and ambiguous expert
knowledge and build expert knowledge repository. By an example it illustrates how to establish cartographic expert
knowledge repository and how the formalized expert knowledge to control the geographic features' symbolization. And
then, it elaborates how the formalized cartographic expert knowledge to controls the annotations' symbolization on a
map.
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