Difference (from revision 11 to 12)
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Relations (aka predicates as in the proposition "the door '''is in front of ''' me) start with seemingly basic things such as topological and qualitative ideas of "near", "connected", "in front of" and "around" as well as other common spatial relationships in use, equals, disjoint, intersects, touches, crosses, within, contains, and overlaps. Spatial objects include abstract spatial notions such as "place" or "locations". Geospatial objects, such as a city or lake may be abstracted to geometrical concepts like a point or polygon area concepts in order to be understood at different levels of granularity. Thus an area like DC can be presented as a small oval on a national map or a complex area when zoomed up close. Features include "size" and "volume". These provide summative information about spatial things. Besides these simple ideas it also includes more macro, aggregated and complex concepts like "river", "estuary", "pond" and "lake". Knowledge about each of these would include relations to other things (e.g. each has boundaries with non-water objects, a river may connect to a lake etc.) Ontologies attempt to define and distinguish all of these concepts in explicit and precise ways to avoid confusions. It also my provide semantic glue by which diverse sources of information are brought together. At the 2009 SOCoP workshop John Bateman (University of Bremen) discussed ontolgoical issues in bringing together sources as diverse as: {nid 2JOH} |
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Relations (aka predicates as in the proposition "the door '''is in front of ''' me) start with seemingly basic things such as topological and qualitative ideas of "near", "connected", "in front of" and "around" as well as other common spatial relationships in use, equals, disjoint, intersects, touches, crosses, within, contains, and overlaps. Spatial objects include abstract spatial notions such as "place" or "locations". Geospatial objects, such as a city or lake may be abstracted to geometrical concepts like a point or polygon area concepts in order to be understood at different levels of granularity. Thus an area like DC can be presented as a small oval on a national map or a complex area when zoomed up close. Features include "size" and "volume". These provide summative information about spatial things. Besides these simple ideas it also includes more macro, aggregated and complex concepts like "river", "estuary", "pond" and "lake". Knowledge about each of these would include relations to other things (e.g. each has boundaries with non-water objects, a river may connect to a lake etc.) Ontologies attempt to define and distinguish all of these concepts in explicit and precise ways to avoid confusions. It also my provide semantic glue by which diverse sources of information are brought together. At the 2009 SOCoP workshop John Bateman (University of Bremen) discussed ontolgoical issues in bringing together sources as diverse as: {nid 2JOH} |
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Getting such diverse areas of expertise to talk to each other is a challenge because the knowledge comes from different communities with different interests and it is often formalized using different (data) representations. For all of these reasons communities, including geo-science communities, wind up with divers pools of knowledge maintained in very different systems unable to share information. {nid 2JON} |
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Getting such diverse areas of expertise to talk to each other is a challenge because the knowledge comes from different communities with different interests and it is often formalized using different (data) representations. For all of these reasons communities, including geo-science communities, wind up with divers pools of knowledge maintained in very different systems unable to share information. {nid 2JOT} |
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Even ontologies differ starting with different primitives and making different distinctions. But often simple alignments can be made to bring general and domain ontologies, such as geospatial ones together. An example of inserting some of the previous USGS region ontology into another ontology called SUMO (Suggested Upper Merged Ontology see http://www.ontologyportal.org/) is shown below. http://ontolog.cim3.net/file/work/SOCoP/Pictures/Potion%20of%20Sumo%20Ontology%20with%20some%20USGS%20Geo-concepts.jpg {nid 2JOS} |