Web sémantique : quand le Web devient données : Introduction Quand la donnée prend le dessus. C’est ainsi que pourrait être, très vulgairement, résumé le Web sémantique. Un vaste projet qui a éclaté aux yeux de tous suite à l‘intervention de Tim Berners-Lee, patron du W3C - et également père du Web -, le consortium en charge de définir les standards du Web. Dans un entretien réalisé par le Courrier Unesco en 2000, il est parvenu à transmettre sa vision d’un autre web. Non pas le web 2.0, qui aujourd’hui bouleverse les usages du Web en donnant la parole aux internautes, en rendant le web plus participatif, non pas le Web 3.0 dont les contours restent encore aujourd’hui à géométrie variable - on parle notamment d’Internet des objets. “J’ai un double rêve pour le Web. Une vision un peu magique d’un environnement connecté où seul le sens de l’information, de la donnée serait pris en compte pour livrer à l’internaute une information riche, contextualisée et fortement qualifiée.
Semantic Web Client Library The Sematic Web Client Library represents the complete Semantic Web as a single RDF graph. The library enables applications to query this global graph using SPARQL- and find(SPO) queries. To answer queries, the library dynamically retrieves information from the Semantic Web by dereferencing HTTP URIs, by following rdfs:seeAlso links, and by querying the Sindice search engine. Contents 1. There is a recent tendency in the Semantic Web community to stress the Web aspect of the Semantic Web, meaning that the Semantic Web is increasingly understood as a single, global information space consisting of interlinked RDF data. This tendency is carried by the revival of ideas around interlinking data on the Semantic Web: Current W3C efforts stress the fact that URI references should be dereference-able (W3C working draft on Best Practice Recipes for Publishing RDF Vocabularies). Technically, the library represents the Semantic Web as a single Jena RDF graph or Jena Model. 2. The paper 3. Query 4. 5.
RDF Book Mashup The RDF book mashup demonstrates how Web 2.0 data sources like Amazon, Google or Yahoo can be integrated into the Semantic Web. The RDF book mashup makes information about books, their authors, reviews, and online bookstores available on the Semantic Web. This information can be used by RDF tools and you can link to it from your own Semantic Web data. Contents News 2009/07/17: GoodRelations support added. 1. The vision of the Semantic Web is to build a global information space consisting of linked data. The goal of the RDF book mashup is to show how Web 2.0 data sources can be integrated into the Semantic Web, meaning that Web 2.0 data can be browsed using generic RDF browsers like Tabulator and can be crawled and cached by Semantic Web search engines like SWSE, SWOOGLE or the Semantic Web Client Library, which will eventually make it possible to query the complete Web using the SPARQL query language. The book mashup applies these principles to Web 2.0 data about books. 2. 3. 4. 5. 6.
SweoIG/TaskForces/CommunityProjects/LinkingOpenData - ESW Wiki News 2014-12-03: The 8th edition of the Linked Data on the Web workshop will take place at WWW2015 in Florence, Italy. The paper submission deadline for the workshop is 15 March, 2015. 2014-09-10: An updated version of the LOD Cloud diagram has been published. The new version contains 570 linked datasets which are connected by 2909 linksets. New statistics about the adoption of the Linked Data best practices are found in an updated version of the State of the LOD Cloud document. 2014-04-26: The 7th edition of the Linked Data on the Web workshop took place at WWW2014 in Seoul, Korea. The workshop was attended by around 80 people. Project Description The Open Data Movement aims at making data freely available to everyone. The goal of the W3C SWEO Linking Open Data community project is to extend the Web with a data commons by publishing various open data sets as RDF on the Web and by setting RDF links between data items from different data sources. Clickable version of this diagram. Demos
Semantic Web Crawling: A Sitemap Extention Abstract This document describes an extension to the Sitemap protocol targeted at the efficient discovery and use of RDF data. The extension allows Data publishers to state where documents containing RDF data are located, and to advertise alternative means to access it, such as data dumps and SPARQL endpoints. Semantic Web clients and crawlers can use this information to choose the most efficient access method for the task they have to perform. Table of Contents 1. Data on the Semantic Web can be made available and consumed in many ways. For example, a Semantic Web crawler that wants to index an entire database might prefer to download the dump, instead of retrieving the data piecemeal by fetching individual URIs. In either case, clients can only make smart decisions if the publisher has advertised the fact that the same data is available through different access method. Publishers should be aware that a sitemap does not enforce any client behaviour. 2. 3. 4. 5. 6. 7. slicing="subject" 8.
Linked Data | Linked Data - Connect Distributed Data across the 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. This version: Latest version: Previous version: Editors: Eric Prud'hommeaux, W3C <eric@w3.org> Andy Seaborne, Hewlett-Packard Laboratories, Bristol <andy.seaborne@hp.com> Please refer to the errata for this document, which may include some normative corrections. See also translations. Copyright © 2006-2007 W3C® (MIT, ERCIM, Keio), All Rights Reserved. Abstract RDF is a directed, labeled graph data format for representing information in the Web. Status of This Document This section describes the status of this document at the time of its publication. This is a W3C Recommendation. Appendices 1 Introduction Data: Query: ? ? ? ?
Resource Description Framework (RDF) / W3C Semantic Web Activity 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