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RDF - Semantic Web Standards

RDF - Semantic Web Standards
Overview 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. Recommended Reading The RDF 1.1 specification consists of a suite of W3C Recommendations and Working Group Notes, published in 2014. A number of textbooks have been published on RDF and on Semantic Web in general. Discussions on a possible next version of RDF

http://www.w3.org/RDF/

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RDFizers RDFizers glossary definition:=The RDFizer project is directory of tools for converting various data formats into RDF. In addition we provide a home for some of these tools. What can I do with these? You can have a computer generate the RDF representation of your data for you, instead of you doing it by hand. Why were they built? SPARQL Query Language for RDF W3C Recommendation 15 January 2008 New Version Available: SPARQL 1.1 (Document Status Update, 26 March 2013) The SPARQL Working Group has produced a W3C Recommendation for a new version of SPARQL which adds features to this 2008 version.

SWValidators - Semantic Web Standards This page tries to collect what the current situation is with SW related validators what could be added with a reasonable amount of work The page was created after Semantic Web Coordination Group discussions, noting that the current RDF validator has not been actively developed for several years. While it is functional and serves a basic purpose, there is always the potential for improvements. Meanwhile, the RDF family of W3C standards has grown; we now have a query language (SPARQL), also based on RDF patterns; a powerful ontology language (OWL), rules framework (RIF) and more options for encoding RDF data (GRDDL, Turtle etc). For newcomers, this range of standards can be daunting.

Resource Description Framework (RDF) Schema Specification 1.0 W3C Candidate Recommendation 27 March 2000 This Version: Latest Version: Previous Version: What Is RDF? Joshua Tauberer July 26, 2006 Editor's Note: "What Is RDF" was originally written by Tim Bray in 1998 and updated by Dan Brickley in 2001. Recently it seemed like time for another update, particularly to relate RDF and the Semantic Web to the cutting edge of web development. We've republished the original in a new location and offer the following update.

Semantic Web I have an idea that I think is very important but I haven’t yet polished to the point where I’m comfortable sharing it. I’m going to share it anyway, unpolished, because I think it’s that useful. So here I am, handing you a dull, gray stone, and I’m saying there’s a diamond inside. Maybe even a dilithium crystal.

ISO 25964 ISO 25964 is the international standard for thesauri, published in two parts as follows: ISO 25964 Information and documentation - Thesauri and interoperability with other vocabularies Part 1: Thesauri for information retrieval [published August 2011] Part 2: Interoperability with other vocabularies [published March 2013] It was issued by ISO, the International Organization for Standardization, and its official website [1] is maintained by its Secretariat in NISO, the USA National Information Standards Organization. What is difference b/w rdfs:domain and rdfs:range.? From a very simplistic point of view, the domain and range properties are there to give you insight into the way that the property links a subject to an object. In the case of the domain property, when you link a subject to an object using a property with this associated attribute, then the subject qualifies as a type of thing specified in the domain. For example, we look at a vocabulary and we see that the domain of the the "drives" property is a "Person" so, simply put, as long as the subject being is described using the “drives” attribute is a type of "Person" (or could be a type of "Person"), then you should have no problem going ahead using that term to describe that thing, because most other people will interpret that if something is described using this term, then it is a "Person".

Notation3 (N3): A readable RDF syntax Up to Design Issues An RDF language for the Semantic Web This article gives an operational semantics for Notation3 (N3) and some RDF properties for expressing logic. These properties, together with N3's extensions of RDF to include variables and nested graphs, allow N3 to be used to express rules in a web environment. This is an informal semantics in that should be understandable by a human being but is not a machine readable formal semantics. This document is aimed at a logician wanting to a reference by which to compare N3 Logic with other languages, and at the engineer coding an implementation of N3 Logic and who wants to check the detailed semantics.

What Is RDF? Tim Bray 2001 January 24, 2001 Spanish Translation available here. This article was first published as "RDF and Metadata" on XML.com in June 1998. Profile for latest GRDDL transformation for RDFa This page is a profile for GRDDL source documents using the latest GRDDL RDFa transform. Currently the use of this profile licenses RDF data extracted by 2008/09/03/RDFa2RDFXML.xsl from an RDFa source. If you want to declare that a document contains RDFa and always uses the latest profile, add this profile to the head of your XHTML: <head profile=" If you want to use a specific version of the transformation, use the specific profile of that version, e.g.: <head profile=" or reference the transformation directly, e.g.: <head profile=" (...)

Problems of the RDF model: Blank Nodes There is a number of challenges regarding the realization of the Semantic Web vision. In the series of blog posts to follow, I’ll be focusing on the Linked Data field and the ideas, technologies and standards it’s based on. I’ll analyze the problems of the three important aspects of Linked Data: the RDF model, the RDF notation and the drawbacks of Linked Data itself. Problems regarding the RDF model RDF is a data model that represents knowledge in the form of simple statements called RDF triples, which consist of a subject, a predicate and an object, like a simple sentences in a human language. The subject is a thing (resource) that a statement describes, the predicate of a statement identifies a property or a relation, while the object is a value of a property or a target of a relation.

Primer - Getting into the semantic web and RDF using N3 [translations into other languages ] The world of the semantic web, as based on RDF, is really simple at the base. This article shows you how to get started. The Semantic Web: An Introduction This document is designed as being a simple but comprehensive introductory publication for anybody trying to get into the Semantic Web: from beginners through to long time hackers. Recommended pre-reading: the Semantic Web in Breadth. Table Of Contents

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