Scientific- Research Quarterly of Geographical Data (SEPEHR)

Scientific- Research Quarterly of Geographical Data (SEPEHR)

Abstracting and Formalizing Model Generalization

Document Type : Research Paper

Author
Mahdi Modiri
Associate Professor of Urban planning, Malek-Ashtar University of Technolog
Abstract
Map generalization, in accordance with different needs of users, is carried out using a multi-scale database. Such production is based on the analysis of map preparation requirements according to users’ needs, and indicates different requests and limitations of user’s desirable cartography.
In this paper, the process of generalization is expressed as a function of a non-generalized universal set to a generalized target set. Both these sets are defined by the ground-space qualities. The universal set keeps certain qualities including geometric, topological and non-space (like compound) qualities. These characteristics must be preserved by using generalization and so, the target set follows the qualities of universal set. Keeping these qualities unchanged causes that the generalization function preserve a state of consistency between the two collections with ground-space signs. Constant qualities are recorded and are found out as a result with consistent emphases. Consistent emphases bring about a state of consistency from a series of generalized information as a support for the structure of generalization function.
Keywords
generalization model
generalization function
topological and geometric qualities
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Scientific- Research Quarterly of Geographical Data (SEPEHR)
Volume 18, Issue 69
Spring 2009
Pages 2-12