Date of Award
Fall 12-20-2019
Level of Access Assigned by Author
Open-Access Thesis
Degree Name
Doctor of Philosophy (PhD)
Department
Spatial Information Science and Engineering
Advisor
Max J. Egenhofer
Second Committee Member
Kate Beard-Tisdale
Third Committee Member
Torsten Hahmann
Additional Committee Members
Robert D. Franzosa
John R. Herring
Abstract
Regions and lines are common geographic abstractions for geographic objects. Collections of regions, lines, and other representations of spatial objects form a spatial scene, along with their relations. For instance, the states of Maine and New Hampshire can be represented by a pair of regions and related based on their topological properties. These two states are adjacent (i.e., they meet along their shared boundary), whereas Maine and Florida are not adjacent (i.e., they are disjoint).
A detailed model for qualitatively describing spatial scenes should capture the essential properties of a configuration such that a description of the represented objects and their relations can be generated. Such a description should then be able to reproduce a scene in a way that preserves all topological relationships, but without regards to metric details.
Coarse approaches to qualitative spatial reasoning may underspecify certain relations. For example, if two objects meet, it is unclear if they meet along an edge, at a single point, or multiple times along their boundaries. Where the boundaries of spatial objects converge, this is called a spatial intersection. This thesis develops a model for spatial scene descriptions primarily through sequences of detailed spatial intersections and object containment, capturing how complex spatial objects relate.
With a theory of complex spatial scenes developed, a tool that will automatically generate a formal description of a spatial scene is prototyped, enabling the described objects to be analyzed. The strengths and weaknesses of the provided model will be discussed relative to other models of spatial scene description, along with further refinements.
Recommended Citation
Lewis, Joshua, "A Qualitative Representation of Spatial Scenes in R2 with Regions and Lines" (2019). Electronic Theses and Dissertations. 3120.
https://digitalcommons.library.umaine.edu/etd/3120