Outils Froids présente: TextRunner un moteur de recherche sémantique pour interroger le web

"TextRunner, mis en ligne récemment par le Department of Computer Science Engineering de l''Université de Washington, nous donne un bel avant-goût de ce que l'on peut attendre de la recherche sémantique.
Il permet en effet d'interroger 500 millions de pages web en utilisant des triplets. Kesako? Le triplet est ce qui va vous permettre de lancer des requêtes plus "intelligentes" que celles permises par les moteurs classiques en vous donnant la possibilité de les structurer un minimum. [...]"

A voir aussi:

Sindice, The semantic web index

"Over 10 billion pieces of reusable information can already be found across 100 million web pages which embed RDF and Microformats."

Introduction to RDFa

"RDFa (“Resource Description Framework in attributes”) is having its five minutes of fame: Google is beginning to process RDFa and Microformats as it indexes websites, using the parsed data to enhance the display of search results with “rich snippets.” Yahoo!, meanwhile, has been processing RDFa for about a year. With these two giants of search on the same trajectory, a new kind of web is closer than ever before.

The web is designed to be consumed by humans, and much of the rich, useful information our websites contain, is inaccessible to machines. People can cope with all sorts of variations in layout, spelling, capitalization, color, position, and so on, and still absorb the intended meaning from the page. Machines, on the other hand, need some help.

A new kind of web—a semantic web—would be made up of information marked up in such a way that software can also easily understand it. Before considering how we might achieve such a web, let’s look at what we might be able to do with it. [...]"

(source: A List Apart / via Catalogablog, 26/06/09)

Interpretations of the Web of Data

"The emerging Web of Data utilizes the web infrastructure to represent and interrelate data. The foundational standards of the Web of Data include the Uniform Resource Identifier (URI) and the Resource Description Framework (RDF). URIs are used to identify resources and RDF is used to relate resources. While RDF has been posited as a logic language designed specifically for knowledge representation and reasoning, it is more generally useful if it can conveniently support other models of computing. In order to realize the Web of Data as a general-purpose medium for storing and processing the world's data, it is necessary to separate RDF from its logic language legacy and frame it simply as a data model. Moreover, there is significant advantage in seeing the Semantic Web as a particular interpretation of the Web of Data that is focused specifically on knowledge representation and reasoning. By doing so, other interpretations of the Web of Data are exposed that realize RDF in different capacities and in support of different computing models."

(source: arXiv, 21/05/09)

Representing Content in RDF (W3C Working Draft 8 sept. 2008)

"This document is a specification for a vocabulary to represent Content in RDF. This vocabulary is intended to provide a flexible framework within different usage scenarios to semantically represent any type of content, be it on the Web or in local storage media. For example, it can be used by Web accessibility evaluation tools to record a representation of the assessed Web content in an Evaluation And Report Language (EARL) 1.0 Schema evaluation report. The document contains introductory information on its usage and some examples."

Les 6 documents de recommandations du W3C pour RDF sont désormais disponibles en français.

Via Planet RDF

Un nouveau groupe de travail a été créé au W3C: RDB2RDF Incubator Group. [Cf. la charte]

The goal of this effort is standardization of approaches (syntax and methodology) for mapping Relational Data Model instance data to RDF (Graph Data Model).

Via Planet RDF

RDFa Syntax Last Call Working Draft

The Semantic Web Deployment Working Group and the XHTML 2 Working Group have published the Last Call Working Draft of RDFa in XHTML: Syntax and Processing. RDFa is a specification for attributes to be used with languages such as HTML and XHTML to express structured data. When publishers can express structured data, and when tools can read it, a new world of user functionality becomes available, letting users transfer structured data between applications and web sites, and allowing browsing applications to improve the user experience. For example, a photo's creator, camera setting information, resolution, location and topic can be published as easily as the original photo itself, enabling structured search and sharing. With RDFa, the rendered, hypertext data of XHTML is reused, so that publishers don't need to repeat significant data in the document content.

Source: W3C via Planet RDF

DCMI signale la parution de nouvelles recommandations: "Expressing Dublin Core metadata using the Resource Description Framework (RDF)".

"This document provides recommendations for expressing DC metadata using RDF, the Resource Description Framework. It does this by describing how the features of the DCMI Abstract Model [ABSTRACT-MODEL] are represented using the RDF model (or abstract syntax), as defined by the RDF Concepts and Abstract Syntax specification [RDF-CONCEPTS]. It does not rely on any specific RDF syntax encoding, though examples using the RDF/XML Syntax Specification [RDF-SYNTAX-GRAMMAR] are provided in Appendix A. This allows Dublin Core metadata to be encoded using this specification in any RDF encoding syntax or other RDF representation system, such as RDF databases."

...

Voir aussi, toujours via DCMI: A major maintenance update of "DCMI Metadata Terms" and the related RDF schemas has been released with improved definitions and usage comments, differentiation between Syntax Encoding Schemes and Vocabulary Encoding Schemes, and the specification of formal domains and ranges for properties.

Planet RDF signale cette vidéo: RDFa Basics (disponible sur YouTube).

RDFa in XHTML: Syntax and Processing (W3C)
A collection of attributes and processing rules for extending XHTML to support RDF

"The modern Web is made up of an enormous number of documents that have been created using HTML. These documents contain significant amounts of structured data, which is largely unavailable to tools and applications. When publishers can express this data more completely, and when tools can read it, a new world of user functionality becomes available, letting users transfer structured data between applications and web sites, and allowing browsing applications to improve the user experience: an event on a web page can be directly imported into a user's desktop calendar; a license on a document can be detected so that users can be informed of their rights automatically; a photo's creator, camera setting information, resolution, location and topic can be published as easily as the original photo itself, enabling structured search and sharing."

Via Planet RDF