By Pim Keizer A simple example of some generic sparql queries for use in a search engine. Search phrase: “Adidas” Instance match Select all instances with label "Adidas". SELECT * WHERE { ?resource rdfs:label "Adidas" . } Find synonyms Select all classes that are of the same type. SELECT ?synonyms WHERE { ?resource rdfs:label "Adidas" . ?resource rdf:type ?type . ?synonyms rdf:type ?type . } Find other instances [...]
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There has been many research in the domain of mapping relational data from databases like MySQL or Oracle to RDF data. D2R Server - http://www4.wiwiss.fu-berlin.de/bizer/d2r-server/ Publishing information about the Web-based Systems Group @ Freie Universität Berlin. It can be accessed using (1) your plain old web browser (2) Semantic Web browsers (3) SPARQL query clients. Virtuoso - http://virtuoso.openlinksw.com/ Virtuoso is an innovative enterprise grade server that cost-effectively delivers an unrivaled platform for Data Access, Integration and Management.
New website: www.XPath.nl On this website a function reference for XPath is found. The option to use the RSS feed makes it possible to place the link in the toolbar of your browser. From there you are always one click away from the information. Very useful for developers of XSD, XSLT and schematron.
RDF is short for Resource Description Framework. RDF is the language for describing resources and contents in the semantic web. In the semantic web RDF is used to describe resources on the web. Resources are addressed by a unique URI. A URI looks like a normal Internet URL. Look at the following fragment of a RDF file: <?xml version="1.0"?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:owl="http://www.w3.org/2002/07/owl#" xmlns:xsd="http://www.w3.org/2001/XMLSchema#" xmlns="http://example.org/pets#" xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#" xml:base="http://example.org/pets"> <owl:Class rdf:ID="Goldfish"> [...]
Describing things in a way that computer applications can understand it. The semantic web describes relations between concepts. For example: A isPartOf B B hasType C C isMemberOf D Also properties of concepts can be described: A hasAge X B hasSize X C has Length X Where in this case X could be of type Integer.
December 3rd Protege 4.0 was released. So, what is new in this version? First of all it supports the OWL 2.0 specification, which is approaching approval. Other new features in this release are: support for editing multiple ontologies, menu drag and drop user interface elements, the ability to import from repositories on the web and more. Anyway, you can download it here.
Are you getting errors about the “RA layer request failed” and “svn: PROPFIND request failed on ..”, followed by an error about not being able to connect to the SVN server? Well, here is what to do: Install the latest Subclipse plugin for Eclipse. Read the manual at Subclipse Set the right proxy settings at the Subversive-config-file (usuallylocated at C:\Documents and Settings\MyUserId\Application Data\Subversion\servers). At the bottom of the file you’ll find http-proxy-host and http-proxy-port. Uncomment [...]
