ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS", Bangkok, May 23-25, 2001
ISPRS, Vol.34,
24
out spatial relation represent some constrains among spatial
relations. Obviously, ordering information is less constraining
than metric information. It may be less clear though, that
ordering information yields stronger constraints than topological
information (Christoph Schieder, 1995). At present the
formalization description and reasoning model of spatial relation
lack the integrated consideration of these three kind of spatial
relations. Combine these three spatial relations together,
analysis the potential influence among each other, and build an
integrated description and reasoning model of them, it will
enhance the uniqueness of spatial description and the accuracy
of spatial reasoning. The discussion in section 3 and 4 show that
the integrated description and reasoning of topological, direction
and distance will bring manful results.
Direction is an important spatial relation. Because of the different
need in small-scale space and large-scale space, direction
relations need to be described at different levels of detail. In this
paper we propose a three level hierarchical qualitative direction
description model and present a unified topological
representation of spatial objects for directions. In different level it
should build different description and reasoning models, these
models combine and complement each other. In this way,
direction relation description is extended.
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THE APPI
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