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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.

The mutual conversion between analog map and digital map is two main contents of the study on digital mapping, which is the production of paper map and spatial data. The visualization of spatial data is the common problem that the spatial data application system confronted, so it is practically meaningful to study the mutual conversion between analog map and digital map. The paper indicates the two processes of the decrease and increase of cartographic information content in two conversions, educes a cartographic information transfer model based on Shannon communication system model, and makes a deep quantitative and qualitative analysis on the decrease and increase of cartographic information in analog/digital conversion in terms of information theory and cartographic theory. The paper also shows that the accuracy of cartographic information should be improved in analog-digital conversion and the information content transformed should be increased to the fullest extent in digital-analog conversion. The corresponding disposal is respectively given for the two processes.