Resource Description Framework (RDF) Language
An Resource Description Framework (RDF) Language is a W3C metadata modeling language for describing the interrelationships between two web resources in the form of subject-predicate-object RDF triples.
- Context:
- It can (typically) have a Semantic RDF Triple Syntactic Construct: Subject, Predicate Relation, and Object.
- It can be used to define an RDF Statement (within an RDF graph).
- It can be associated to an RDF Schema Language (which can describe how to use RDF to describe an RDF vocabulary).
- It can (typically) not allow for Cardinality Constraints on Relation Variables, such as Zero-or-One.
- …
- Example(s):
- RDF 1999 (on top of XML Standard for encoding Metadata).
- RDF 2007.
http://www.w3.org/2009/12/rdf-ws/cfp.- …
- Counter-Example(s):
- See: W3C, Lightweight Ontology, SchemaWeb, SPARQL, Turtle Syntax, Gremlin Language, RDFS, Web Ontology Language, Rule Interchange Format, RDFa, Named Graph, Ontology Language, Entity–Relationship Model, Class Diagram, Entity–Attribute–Value Model.
References
2023
- (Wikipedia, 2023) ⇒ https://en.wikipedia.org/wiki/Resource_Description_Framework Retrieved:2023-6-8.
- The Resource Description Framework (RDF) is a World Wide Web Consortium (W3C) standard originally designed as a data model for metadata. It has come to be used as a general method for description and exchange of graph data. RDF provides a variety of syntax notations and data serialization formats, with Turtle (Terse RDF Triple Language) currently being the most widely used notation.
RDF is a directed graph composed of triple statements. An RDF graph statement is represented by: 1) a node for the subject, 2) an arc that goes from a subject to an object for the predicate, and 3) a node for the object. Each of the three parts of the statement can be identified by a URI. An object can also be a literal value. This simple, flexible data model has a lot of expressive power to represent complex situations, relationships, and other things of interest, while also being appropriately abstract.
RDF was adopted as a W3C recommendation in 1999. The RDF 1.0 specification was published in 2004, the RDF 1.1 specification in 2014. SPARQL is a standard query language for RDF graphs. RDFS, OWL and SHACL are ontology languages that are used to describe RDF data.
- The Resource Description Framework (RDF) is a World Wide Web Consortium (W3C) standard originally designed as a data model for metadata. It has come to be used as a general method for description and exchange of graph data. RDF provides a variety of syntax notations and data serialization formats, with Turtle (Terse RDF Triple Language) currently being the most widely used notation.
2020
- (Wikipedia, 2020) ⇒ https://en.wikipedia.org/wiki/Resource_Description_Framework Retrieved:2020-3-31.
- The Resource Description Framework (RDF) is a family of World Wide Web Consortium (W3C) specifications originally designed as a metadata data model. ...
2020b
- (Wikipedia, 2020) ⇒ https://en.wikipedia.org/wiki/Resource_Description_Framework#Overview Retrieved:2020-3-31.
- The RDF data model is similar to classical conceptual modeling approaches (such as entity–relationship or class diagrams). It is based on the idea of making statements about resources (in particular web resources) in expressions of the form subject–predicate–object, known as triples. The subject denotes the resource, and the predicate denotes traits or aspects of the resource, and expresses a relationship between the subject and the object. For example, one way to represent the notion "The sky has the color blue" in RDF is as the triple: a subject denoting "the sky", a predicate denoting "has the color", and an object denoting "blue". Therefore, RDF uses subject instead of object (or entity) in contrast to the typical approach of an entity–attribute–value model in object-oriented design: entity (sky), attribute (color), and value (blue). RDF is an abstract model with several serialization formats (i.e. file formats), so the particular encoding for resources or triples varies from format to format. This mechanism for describing resources is a major component in the W3C's Semantic Web activity: an evolutionary stage of the World Wide Web in which automated software can store, exchange, and use machine-readable information distributed throughout the Web, in turn enabling users to deal with the information with greater efficiency and certainty. RDF's simple data model and ability to model disparate, abstract concepts has also led to its increasing use in knowledge management applications unrelated to Semantic Web activity. A collection of RDF statements intrinsically represents a labeled, directed multi-graph. This in theory makes an RDF data model better suited to certain kinds of knowledge representation than are other relational or ontological models. However, in practice, RDF data is often stored in relational database or native representations (also called Triplestores — or Quad stores, if context such as the named graph is also stored for each RDF triple). [1]
As RDFS and OWL demonstrate, one can build additional ontology languages upon RDF.
- The RDF data model is similar to classical conceptual modeling approaches (such as entity–relationship or class diagrams). It is based on the idea of making statements about resources (in particular web resources) in expressions of the form subject–predicate–object, known as triples. The subject denotes the resource, and the predicate denotes traits or aspects of the resource, and expresses a relationship between the subject and the object. For example, one way to represent the notion "The sky has the color blue" in RDF is as the triple: a subject denoting "the sky", a predicate denoting "has the color", and an object denoting "blue". Therefore, RDF uses subject instead of object (or entity) in contrast to the typical approach of an entity–attribute–value model in object-oriented design: entity (sky), attribute (color), and value (blue). RDF is an abstract model with several serialization formats (i.e. file formats), so the particular encoding for resources or triples varies from format to format. This mechanism for describing resources is a major component in the W3C's Semantic Web activity: an evolutionary stage of the World Wide Web in which automated software can store, exchange, and use machine-readable information distributed throughout the Web, in turn enabling users to deal with the information with greater efficiency and certainty. RDF's simple data model and ability to model disparate, abstract concepts has also led to its increasing use in knowledge management applications unrelated to Semantic Web activity. A collection of RDF statements intrinsically represents a labeled, directed multi-graph. This in theory makes an RDF data model better suited to certain kinds of knowledge representation than are other relational or ontological models. However, in practice, RDF data is often stored in relational database or native representations (also called Triplestores — or Quad stores, if context such as the named graph is also stored for each RDF triple). [1]
- ↑ Optimized Index Structures for Querying RDF from the Web Andreas Harth, Stefan Decker, 3rd Latin American Web Congress, Buenos Aires, Argentina, October 31 to November 2, 2005, pp. 71–80
2017
- (Williams & Oliva, 2017) ⇒ T Williams, and A Oliva. (2017). “Breaking the Mold: Clinical Trials Data As RDF.” In: Proceedings of the PhUSE Annual Conference.
- QUOTE: ... This paper outlines the philosophy, ontology, and methods adopted by the PhUSE project "Clinical Trials Data as RDF". By modeling to the data instead of to a specific standard, Resource Description Framework (RDF) supports a future-proof, multi-dimensional data store for clinical trials data while enabling strong compliance to past, present, and future submission standards. ...
2011
- (W3, 2011) ⇒ http://www.w3.org/RDF/
- RDF is a standard model for data interchange on the Web. RDF has features that facilitate data merging even if the underlying schemas differ, and it specifically supports the evolution of schemas over time without requiring all the data consumers to be changed.
- RDF extends the linking structure of the Web to use URIs to name the relationship between things as well as the two ends of the link (this is usually referred to as a “triple”). Using this simple model, it allows structured and semi-structured data to be mixed, exposed, and shared across different applications.
- This linking structure forms a directed, labeled graph, where the edges represent the named link between two resources, represented by the graph nodes. This graph view is the easiest possible mental model for RDF and is often used in easy-to-understand visual explanations.
2007a
- (Obitko, 2007) ⇒ Marek Obitko. (2007). “Translations Between Ontologies in Multi-agent Systems - Ontology Operations].” PhD Thesis, Czech Technical University http://www.obitko.com/tutorials/ontologies-semantic-web/body-of-knowledge.html
- Resource Description Framework (RDF) is a framework for representing information about resources in a graph form. Since it was primarily intended for representing metadata about WWW resources, it is built around resources with URI.
Information is represented by triples subject-predicate-object in RDF. An example of a triple is shown in the figure below. It says that "Joe Smith has homepage http://www.example.org/~joe". All elements of this triple are resources defined by URI. The first resource http://www.example.org/~joe/contact.rdf#joesmith (subject) is intended to identify Joe Smith. Note that it precisely defines how to get to a RDF document as well as how to get the joesmith RDF node in it. The second resource http://xmlns.com/foaf/0.1/homepage (predicate) is the predicate homepage from a FOAF (Friend-of-a-friend) vocabulary. The last resource (object) is Joe's homepage http://www.example.org/~joe/.
All of the elements of the triple are resources with the exception of the last element, object, that can be also a literal. Literal in the RDF sense is a constant string value such as string or number. Literals can be either plain literals (without type) or typed literals typed using XML Datatypes."
- Resource Description Framework (RDF) is a framework for representing information about resources in a graph form. Since it was primarily intended for representing metadata about WWW resources, it is built around resources with URI.
2007b
- (Obitko, 2007) ⇒ Marek Obitko. (2007). “Translations Between Ontologies in Multi-agent Systems - Ontology Operations].” PhD Thesis, Czech Technical University http://www.obitko.com/tutorials/ontologies-semantic-web/rdf-graph-and-syntax.html
- These triples together form RDF graph. A graph with the triples from figures showing triple and showing literal and with some additional triples are shown in the figure below. The top triple uses type as a predicate from RDF vocabulary to express that joesmith is of type Person.
A normative syntax for serializing RDF is RDF/XML. The RDF graph from the figure below is written in RDF/XML as follows. Note that it uses XML namespaces with prefixes defined in the beginning of the XML document(...)
RDF/XML is a normative syntax, however, other serialization formats are used as well. The TURTLE and N3 syntax is less verbose than RDF/XML and so is quite popular. The Notation 3 (N3) is designed as a readable language for data on the Web that goes beyond RDF (it contains logical extensions and rules). The Terse RDF Triple Language (TURTLE) is a RDF-only subset of N3. For the purposes of this text these two languages are interchangeable.
- These triples together form RDF graph. A graph with the triples from figures showing triple and showing literal and with some additional triples are shown in the figure below. The top triple uses type as a predicate from RDF vocabulary to express that joesmith is of type Person.
2009
- (Alkhateeb et al., 2009) ⇒ Faisal Alkhateeb, Jean-François Baget, and Jérôme Euzenat. (2009). “Extending SPARQL with Regular Expression Patterns (for Querying RDF).” In: Web Semantics: Science, Services and Agents on the World Wide Web. doi:10.1016/j.websem.2009.02.002
- QUOTE: RDF is a knowledge representation language dedicated to the annotation of resources within the framework of the semantic web. Among the query languages for RDF, SPARQL allows querying RDF through graph patterns, i.e., RDF graphs involving variables.