- Slides: 9
Ontology alignment for Geo-spatial databases
Ontology Alignment l We consider ontologies represented as XML trees. We can map vertices (nodes) from one tree to the other. We establish a global ontology that will be used for querying purposes. The ontologies used by different Jurisdictions are called local ontologies. We map the global ontology to each local one to resolve heterogeneity. l Vertices of the global ontology are mapped to vertices in the local one using different kinds of mapping: exact, subset, superset, approximate, and no mapping (null)
Example of mapping
Mapping types – Exact: the connected vertices exactly refer to the same concept (Car, Automobile) – Subset: the vertex (vertices) in the global ontology is a subset of the vertex in the local ontology (Chinese Food and Thai Food are subset of Oriental Food) – Superset: the vertex in the global ontology is a superset of the vertices in the local ontology (Opposite of Subset) – No Mapping (Null): the vertex in the global ontology does not have a semantically related vertex in the local ontology
Agreement Maker l The agreement maker is a software tool that is used to create the mappings between the global ontology and a local ontology and generate an agreement document containing those mappings. This document is used by a query processor.
Upcoming Work l l Formalize mapping types to cover all possible situations that can happen in a mapping scenario. Re-implement Agreement maker to better accommodate additional tools and capabilities (Dictionaries, virtual nodes in local ontologies…etc)