RDF 1.1 Concepts and Abstract Syntax Yanan Zhang 2018/12/3

contents RDF current status Introduction to RDF 1.1 Concepts and Abstract Syntax Changes from RDF 2004 to this version 2018/12/3

RDF current status RDF Model and Syntax (1999 Recommendation) and RDF Schema (2000 Candidate Recommendation). ……. W3C Recommendation 10 February 2004 RDF Concepts and Abstract Syntax RDF Semantics RDF Primer RDF Vocabulary Description Language 1.0 :RDF Schema RDF/XML Syntax Specification RDF Test Cases Group notes Microdata to RDF RDF Interfaces RDF 1.1 Concepts and Abstract Syntax(2012-06-05) 2018/12/3

The Resource Description Framework (RDF) is a framework for representing information in the Web. has an abstract syntax that reflects a simple graph-based data model, and formal semantics. that allows data to be shared and reused across application, enterprise, and community boundaries. 2018/12/3

Introduction to RDF 1.1 Concepts and Abstract Syntax  Graph-based Data Model RDF/XML 2018/12/3 Concepts: Triples (subject , predicate , object) Nodes: IRIs blank nodes literals

IRI (Internationalized Resource Identifier) IRIs are a generalization of URIs. IRI:Universal Character Set (Unicode/ISO 10646). URI: a subset of the ASCII character set As globally unique identifiers that describes resources(its referent), and as starting points for RESTful interaction with these resources. http://www.w3.org/2000/10/swap/pim/contact#Person 2018/12/3

RDF Vocabularies and Namespace IRIs a collection of IRIs with clearly established referents intended for use in RDF graphs. eg. classes such as exterms:Tent, properties such as exterms:model, exterms:weightInKg, and exterms:packedSize  RDF Vocabulary Description Language : RDF Schema rdfs:Class rdfs:subClassOf rdf:type rdf:Property rdfs:domain, rdfs:range, and rdfs:subPropertyOf http://www.w3.org/TR/2004/REC-rdf-schema-20040210/ The IRIs in an RDF vocabulary often share a common substring known as a namespace IRI. 2018/12/3

blank node something with the given relationships exists, without explicitly naming it. Replacing blank nodes with IRIs, use a well-known IRI with the registered name genid. http://example.com/.well-known/genid/d26a2d0e98334696f4ad70a677abc1f6 2018/12/3

literal A literal in an RDF graph consists of: a lexical form being a Unicode string, a datatype IRI being an IRI that establishes the literal value. e.g. "27"^^http://www.w3.org/2001/XML Schema#integer "1999-08-16"^^http://www.w3.org/2001/XML Schema#date A language-tagged string is any literal whose datatype IRI is equal to http://www.w3.org/1999/02/22-rdf-syntax-ns#langString. simple literals, datatype IRI http://www.w3.org/2001/XMLSchema#string. In earlier versions of RDF Plain literals Typed literals  2018/12/3

Datatypes The rdf:XMLLiteral Datatype The rdf:HTML Datatype xsd:boolean lexical space lexical-to-value mapping  The XML Schema Built-in Datatypes RDF-compatible XSD types, http://www.w3.org/2001/XMLSchema#xxx, where xxx is the name of a datatype. Added xsd:duration , xsd:dayTimeDuration, xsd:yearMonthDuration and xsd:dateTimeStamp The rdf:XMLLiteral Datatype http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral The rdf:HTML Datatype http://www.w3.org/1999/02/22-rdf-syntax-ns#HTML. 2018/12/3

Changes from RDF 2004 to this version Introduced a datatype for language-tagged strings, and one for HTML fragments Modified the lexical space and value space of the rdf:XMLLiteral datatype Updated the list of RDF-compatible XSD types to reflect XML Schema 1.1 a section on skolemization of blank nodes Add a note that explains that #x0-#x1F are no longer allowed in simple literals Changed “RDF URI Reference” to “IRI” Renamed “graph equivalence” to “graph isomorphism” many updated references to other specifications Added a Conformance section 2018/12/3

Thanks! 2018/12/3