Ontologies in Spatial Data Infrastructures

Doug NebertFederal Geographic Data Committee

Reston, VA November 2009

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Background Confused to about the meaning and utility of “spatial ontology” as this could be construed extremely narrowly as an enhanced gazetteer (problem solved!)

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http://www.spatial.maine.edu/~max/spatializingOntologies.swf

(Max Egenhofer)

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How do geospatial communities use ontologies?

Gazetteer, place name hierarchiesSpatial operationsSpatial relations, associationsVocabularies Spatial feature typology

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Gazetteer interfaces

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GazetteersInclude a set of landmark feature types and the names/identities of individual features within a typeGeographic hierarchy may be managed or impliedAlternate, official, historical, and other variant names may be managedCan be useful for orientation, refining search, providing geographic context

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Which New York?

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Spatial operations and relations

In the context of performing geospatial analysis there is an ontology of operations (concepts) that are based on mathematical proofsThere are contextual relational terms as well:

Near, far, adjacent Passes under, over, through Neighborhood, region Along, beside

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disjoint contains equalinside

meet covers coveredBy overlap

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Egenhofer 4-intersection matrix

Mathematically defines topological relations between objects and creates an actionable vocabulary

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Vocabularies use of enumerations and code lists within a geospatial community is common to standardize and categorize resources Place code identifiers Coordinate reference systems Parameter (Attribute) value types Service types, standards, URNs

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Geo-enabled data and codes

There is abundant statistical data stored in tables with codes for the geography of interest: Address: street, city, state ZIP Code or ZIP+4 State/County/City code or name Congressional District

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H1N1 (PAHO)

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Feature (class) catalogue

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Semantic Based Knowledge Reasoning for Intelligent Search: Building a common GEOSS Ontology

Abstraction of

Classes and Attributes

Building

Interrelationship

Domain

Ontology ModelConceptualization Facet mapping

Current Knowledge Base:

500 Terminologies and Interrelationships

37 Logic Restrictions

(35 Existential and 2 Universal)

Wenwen Li, GMU

Integral http://testbed.gmu.edu/geoss/geoss_all.owl

Components CEOS-Earth Observation Parameter INSPIRE-Theme INSPIRE-Spatial Ontology Type

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GEOSS Ontology Snapshot

Ontology (Spatial Object Type)Ontology (Theme)

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GEOSS Ontology Snapshot-Contd.

Ontology (CEOS)

Cloud Type of CEOS

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Ontology Improved Search

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Geo-bridge for Meta-Catalogue

Standards: Web Catalogue Service

(CSW) – GOS, ESG Customized API – ECHO Web Interface – GCMD,

NCDCSeamless Communication

XML-encapsulated Request

KVP-based RequestService Parser

HTML parser XML parser

Key Techniques Ajax: Asynchronous

JavaScript and XML Multi-Threads

Wenwen Li, GMU

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Managing heterogeneity in GEO

The construction of a common feature type/property ontology that joins terms from multiple discipline ontologies will allow for use and discovery of information across multiple domains and GEO “Societal Benefit Areas”Managing “observable” properties will allow joins between user or application requirements and available data and service resources

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Bridging communitiesArctic Spatial Data Infrastructure will support multi-disciplinary and multi-lingual map data search, management, and accessSupports the Group on Earth Observations and the Arctic CouncilCandidate vocabularies: GEMET multi-lingual environmental thesaurus INSPIRE Feature Concept Catalog CEOS/NASA/NOAA Observation Types SWEET Ontology NASA GCMD/IDN Science Keywords