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Progress Update Semantic Web, Ontology Integration, and Web Query. Seminar Department of Computing 2006-03-01 David George. Today. Summarise on December issues Resource Description Framework “RDF/XML” . Development of Geographical Ontology Layers for integration and query .
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Progress UpdateSemantic Web,Ontology Integration,and Web Query Seminar Department of Computing 2006-03-01 David George
Today • Summarise on December issues • Resource Description Framework “RDF/XML”. • Development of Geographical Ontology Layers for integration and query. • Discuss development work since then • Database data transformed into Semantic Web data. • Development of a Java interface to create, merge, and query Semantic Web data.
typeOf David George Person RDF Reminder • RDF describes information as a collection of statements in Subject-Predicate-Object form, i.e. the subject and the object and a relationship (predicate) between them. • RDF is a graph-based model for describing how Internet resources relate to each other (e.g. Web pages).
RDF Directed Graph Example RDF Graph <info:Person rdf:about="http://www.uclan.ac.uk/gradschool/conf/dec05/index.htm#DGeorge"> <info:fullName>David George</info:fullName> <info:mailbox rdf:resource="mailto:dgeorge@uclan.ac.uk"/> <info:activity>Research Student</info:activity> <info:presentation rdf:resource="http://www.uclan.ac.uk/gradschool/conf/dec05/George-D-ppt.htm"/> </info:Person>
workedAt marriedTo hasVisited availableAt hasVisited hasInfo RDF can form complex directed graphs of nodes linked by relationships. Library Susan David TravelGuide Denver • Graph model is useful for describing data and also Ontology structures using Web Ontology Language (OWL).
Geographical Ontology • Ontology is a formalvocabulary defining: • concepts and their attributes. • relationships between concepts. • constraints on those relationships.
<owl:Class rdf:ID="PopulationGroup"/> <owl:DatatypeProperty rdf:ID="gridRef"> <rdfs:domain rdf:resource="#PopulationGroup"/> </owl:DatatypeProperty> <owl:Class rdf:about="#Town"> <rdfs:subClassOf rdf:resource="#PopulationGroup"/> </owl:Class> <owl:Class rdf:ID="City"> <rdfs:subClassOf rdf:resource="#PopulationGroup"/> </owl:Class> <Town rdf:ID="Nelson"> <gridRef rdf:datatype="#string">2E52N</gridRef> </Town> <City rdf:ID="Liverpool"> <gridRef rdf:datatype=“#string">3E52N</gridRef> </City> OWL/XML-based Ontology Graph
rivers population economic Water Utility LA. Planning pipelines housing relief Geographic Ontology Layers
Progress update – Integration and Semantic Web • Extracted data from relational DB into normalised XML, and transformed into RDF/XML using XSLT. • Developed RDF/OWL, and MySQL interface using Jena API Toolkit (Hewlett P.Labs.) and Protégé Ontology development tool (MIT). • Interface Objectives: • Create, merge and query RDF triple files. • Persistent data in MySQL, Oracle, Postgres. • Interrogate ontologies over the Web, using inference capability. • Merge heterogeneous Ontology vocabularies.
Road Transportation & Populations OWL Ontology Language
Protégé OWL interface (MIT) Ontology Development Tool
OWL ontology imports <rdf:RDF xmlns:owl="http://www.w3.org/2002/07/owl#" xmlns=http://www.owl-ontologies.com/unnamed.owl#> <owl:Ontology rdf:about=""> <owl:imports rdf:resource="http://193.61.241.101/union/british.owl"/> <owl:imports rdf:resource="http://193.61.241.101/union/american.owl"/> </owl:Ontology> <owl:Class rdf:ID="RetailOperation"> <rdfs:subClassOf> <owl:Class rdf:ID="CorporateEntity"/> </rdfs:subClassOf> </owl:Class> <owl:Class rdf:ID="DistributionOperation"> <rdfs:subClassOf rdf:resource="#CorporateEntity"/> </owl:Class> </rdf:RDF>
Jena Toolkit – RDF/OWL interface Persistent RDF triple storage using MySQL
OWL interface Querying Transport & Population Ontology
Early Conclusions • Progress in small-scale experimentations. • Developed platform for more complex experimentation, involving: • data transformation • data integration • ontology union. • Ontology requires complex specification. • May need to consider inferencing. • Research output to consider “traditional” database comparisons between: • Integration process. • Query process.
person name room email “CM222” “dgeorge@uclan.ac.uk” lastname firstname “David” “George” XML tree XML example: <person> <name> <firstname>David</firstname> <lastname>George</lastname> </name> <room>CM222</room> <email>dgeorge@uclan.ac.uk</email> </person>