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WSFINDER - the wiki for finding Web service and Open APIs

 mars 9, 2008 • Pas de commentaire
Welcome! This is a community effort to create a list of all APIs and web services that are publicly available for people to play with.

We’ve seen the great things that people have done with Open APIs. We hope to encourage more cool stuff to get built and for more companies and developers to open up their APIs. We think that the Web 2.0 world is approaching quickly and that this will accelerate it.

Check out our WSFinder Blog for thoughts, updates and conversation.

233 APIs total with 54 mashups as of 3/8/2007 12:08 AM

Deitel - Web services Ressource Center

 mars 9, 2008 • Pas de commentaire
JSON (JavaScript Object Notation)

JSON Specification<!–(Mon 11/06/2006 @ 04:26)–>
http://tools.ietf.org/html/draft-crockford-jsonorg-json-04 
JSON specification.  
 
JSON-RPC Wiki<!–(Mon 11/06/2006 @ 04:29)–>
http://json-rpc.org/ 
JSON-RPC (remote procedure call) wiki includes the specification and numerous packages for implementing JSON-RPC including Python, Java, C, C#, Perl, PHP, Ruby and others.  
 
Resources for Using JSON with Yahoo! Web Services<!–(Mon 11/06/2006 @ 04:28)–>
http://developer.yahoo.com/common/json.html 
Resources for using JSON with Yahoo! Web services. Includes an overview of JSON and discusses getting JSON output from a Yahoo! Web services request, getting JSON output with output=json, adding a callback with callback=function, JSON versus XML and using JSON in your script or application. 
 
Comparison of JSON to XML<!–(Mon 11/06/2006 @ 04:26)–>
http://www.json.org/xml.html 
Comparison of JSON to XML. Discusses several features of JSON including simplicity, extensibility, interoperability and openness.  
 
Yahoo! group for JSON<!–(Mon 11/06/2006 @ 04:25)–>
http://groups.yahoo.com/group/json/ 
Yahoo! group for JSON.  
 
Introduction to JSON<!–(Mon 11/06/2006 @ 04:24)–>
http://www.json.org/ 
Introduction to JSON. Includes resources including JSON parsers.  
 
Wikipedia entry for JavaScript Object Notation<!–(Mon 11/06/2006 @ 04:23)–>
http://en.wikipedia.org/wiki/JSON 
Wikipedia entry for JSON . (JavaScript Object Notation) is a data interchange format that supports several languages including Java, C, C#, Perl, Python, Ruby, PHP, ActionScript and more. Includes an introduction to JSON and describes how it can be used. Also provides a JSON example and a comparison to XML and other markup languages.  
 
Resource Center
Contents

Ontology & PHP - RAP Overview

 mars 8, 2008 • Pas de commentaire

an ontology is nothing else then a logical theory. The issue is whether such a theory needs to have particular formal properties in order to be an ontology or, rather, whether it is the intended purpose which lets us consider a logical theory as an ontology. The latter position can be supported by arguing that an ontology is an annotated and indexed set of assertion about something: “leaving o‹ the annotations and indexing, this is a collection of assertions: what in logic is called a theory” (Pat Hayes statement in [24]). According to interpretation 4, an ontology is not viewed as a logical theory, but just as the vocabulary used by a logical theory. Such an interpretation collapses into 3.a if an ontology is thought of as a specification of a vocabulary consisting of a set of logical definitions. We may anticipate that the Gruber’s interpretation (specification of conceptualization) collapses into 3.a as well when a conceptualization is intended as a vocabulary. Finally, under interpretation 5, an ontology is seen as a specification of a logical theory in the sense that it specifies the “architectural components” (or primitives) used within a particular domain theory.

oldakowski-rap.pdf or http://www.semanticscripting.org/SFSW2005/papers/Oldakowski-RAP.pdf

http://www4.wiwiss.fu-berlin.de/bizer/rdfapi/tutorial/introductionToRAP.htm

RAP - RDF API for PHP is a Semantic Web toolkit for PHP developers. RAP started as an open source project at the Freie Universität Berlin in 2002 and has been extended with internal and external code contributions since then. Its latest release includes:

  • a statement-centric API for manipulating RDF graphs as a set of statements
  • a resource-centric API for manipulating RDF graphs as a set of resources
  • integrated RDF/XML, N3 and N-TRIPLE parsers
  • integrated RDF/XML, N3 and N-TRIPLE serializers
  • in-memory or database model storage
  • support for the RDQL query language
  • an inference engine supporting RDF-Schema reasoning and some OWL entailments
  • an RDF server providing similar functionality as the Joseki RDF server
  • a graphical user-interface for managing database-backed RDF models
  • support for common vocabularies

RAP can be used under the terms of the GNU LESSER GENERAL PUBLIC LICENSE (LGPL)
and can be downloaded from http://sourceforge.net/projects/rdfapi-php/

RAP offers two different programming interfaces for manipulating RDF graphs: The statement-centric Model API which allows you to manipulate an RDF graph as a set of statements; and the resource-centric ResModel API for manipulating an RDF graph as a set of resources.

The Model API supports adding, deleting, and replacing statements inside a model as well as adding entire models. StatementIterators allow sequential access to all statements within a model. There are four different implementations of the Model API:

Model Functionality
MemModel Model storing its RDF graph in memory. MemModel is fast, but doesn’t support inference.
DbModel Model storing its RDF graph in a relational database. No inference support.
InfModelF Forward-chaining inference model storing its base graph and inferred triples in memory.
InfModelB Backward-chaining inference model storing its base graph in memory and creating inferred triples on the fly.

The resource-centric ResModel API represents RDF graphs as resources having properties. The ResModel API is very similar to the Jena Model API allowing programmers, which are used to Jena, to easily write RAP code. The ResModel API is implemented on top of the Model API. ResModels are always having a underlying MemModel, DbModel, InfModelF or InfModelB and are only providing a resource-centric view on this model. There are two implementations of the ResModel API:

Model Functionality
ResModel Basic implementation of the ResModel API
OntModel OntModel provides a ResModel implementation extended with RDF-Schema specific methods like hasSuperProperty(), addDomain() and listInstances().

RSS syndication

 mars 7, 2008 • Pas de commentaire

Click to return to AbbeNormalRss Syndication

Once we started writing the RSS pages here, i discovered the RssFaq. It’s great!A totally non-technical description (referring to syndication as “publish & subscribe”).There are many RssReaders, and thousands of RssFeeds. Many news sites produce feeds (or others make them available by ’scraping’ the raw HTML). Most WebLogSoftware produce feeds (and some now read them as well!); Also see WikisWithRss.

There are many individual and group RssForums, for discussing the unfortunately-varied RssStandards.

SyndicEight — great source of feeds, tools and advocacy for RSS.

done with JavaScriptRssViewer

 RSS stands for Rich Site Summary, or is it RDF Site Summary? Really Simple Syndication? No one seems to know for sure. It’s like UseNet, but much less organized.Whatever we call it, it makes it easier for you to stay up on dozens or hundreds of other sites. It makes it simple for others to stay up to date on your site even if they won’t visit your web pages all the time. It’s a system of standards and software that lets you publish and/or read RssFeeds of your own and others’ work. The feeds contain titles or headlines, a WebAddress? to the actual item, and optionally a description or summary (or the entire item).

For example, to the left you are seeing syndicated listings of headlines and summaries from the Ben Hammersley.com and Syndication News from Bill Kearney feeds. If you go to either site you’ll see the same articles, but on their web page, with full text, and the usual sidebar of links and so on.

With RssReaders you can browse many feeds, in less time than one would take to go through all the web sites.

Many readers accept the regular URL for a site and will find the feed for themselves. If that doesn’t work, the white-on-orange XML icon () is the most common one for RssFeeds (but see RssIcons). Look for an icon like that, or a link that is labeled with “syndicate” or “feed” (or ends with .xml, .rdf or .rss), and copy it (right click or control-click and “copy URL”) and paste it into your RSS reader wherever it asks for a URL.

Sof items (about anything), possibly with links, possibly with a great deal of other MetaData?. Someone called RSS an event bus. It could easily be extended to represent metadata about a list of files in a folder, a list of e-mails, etc. This may further some sort of useful convergence among these things.

erase? http://www.nwfusion.com/diy/
For syndication of this site see SubscribingToAbbeNormalSee Meatball:PeerToPeerSyndication
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RSS readers

 mars 7, 2008 • Pas de commentaire

This list will, of course, never be complete. If I’m missing anything please let me know.

This file has now been broken-down into RSS readers by platform:

Basil - an easy to use syndicated news reader for Yahoo! Messenger. By installing the Basil plug-in, you can read news headlines from your favourite web feeds (e.g., web sites, blogs, schools, podcasters, etc.) within Messenger, then read the full story with a click of your mouse

EaZy RSS reader - you need Excel 2000 or a later version to use this add-in

FeedBurner Mobile Feed Reader - Requirements: A mobile handset with the J2ME MIDP 2.0/CLDC1.0 platforms, such as the Sony Ericsson P900 and Nokia 6600, and Palm OS 5 with network access (Palm Tungsten T series, Handspring Treo600)

FeedWordPress - an Atom/RSS aggregator for WordPress. Requires WordPress 1.5

Friday - Java front-end for viewing news aggregation sites and site syndication feeds on mobile devices, like phones and PDAs. Friday supports the Syndic8 news aggregation site. In the near future, it will support others, such as Meerkat and NewsIsFree

i-feed.de collects newsfeeds and provides content specific rendering of nearly all types of devices such as mobile phones (WAP or i-mode), PDAs or webbrowsers

immedi.at - helps you to keep track of online information as it changes. It sends you an instant message whenever any RSS or Atom feed you want to monitor changes. immedi.at works with all major IM carriers including MSN Messenger, Yahoo Messenger, Google Talk, Jabber, and AIM/ICQ

iPod Agent - one stop utility for managing contacts, appointments, mail, notes, tasks, RSS feeds, weather, horoscopes, movie showtimes and all other iPod Extras

JavaScript RSS Viewer - provides a neat way to embed such RSS-boxes in any HTML document via a generated JavaScript tag

Jonah - provides a framework for collecting headlines from any site that provides an RSS summary of their content. Future plans include a full-fledged my.netscape type portal with user preferences, stocks, news, weather, and any other content source that users want

JSwingReader - Java/Swing RSS NewsFeed Reader

Macromedia XML News Aggregator (MXNA) - an XML and news feed aggregator written in ColdFusion that allows readers to monitor their favorite weblogs and other syndicated sites in a single place. It aggregates content by parsing, categorizing, and storing RSS XML feeds. The base source code is available on the Macromedia DevNet Resource Kit Volume 3

mefeedia.com - an RSS aggregator for videobloggers. Sign up, choose the videobloggers you like and watch videos! Mefeedia is an experimental videoblogging community side project by Peter Van Dijck

MioMediaBox - for PSP downloads your favorite RSS feeds from the Internet, create high-quality pictures, and sends them to your Sony PSP Device or your MemoryStick Drive. MioMediaBox for PSP is compatible with any Sony PSP device and does not requires any extra software or specific configuration

mReader - a light-weight Mobile RSS Reader (Aggregator) designed to be compatible with J2ME midp devices including Mobile Phones, PDAs and Blackberry

MX RSS Reader-Writer - a 2 in 1 solution. Firstly, it allows you to import RSS (Really Simple Syndication) files and integrate them in your website design and secondly it allows you to export database information into RSS format. Supported server technologies: ColdFusion, ASP_VBScript, PHP_MySQL and PHP_ADODB

myRadio aggregation framework - extends the Radio Userland aggregator from rss to any networked data (xml, html, soap, personalized services, etc), and any layout. It is exceedingly simple for developers to add functionality to the framework

Neomyz RSS Web Reader - remotely hosted. You do not need to download or install anything. All you need to do is insert a few lines of HTML code into your web page. You do not need to care about technologies supported by your webhost, or about system requirements of RSS Web Reader

News Monkey - Flash RSS and blog Reader/Aggregator

NewsGator Go! for Windows Mobile - allows users to read content and manage subscriptions directly from any device running the Windows Mobile 2003 or Windows Mobile 5.0 or later operating systems, including the Palm Treo 700w, Motorola Q, Cingular 2125 and HP iPaqs

NewsGator Media Center Edition - will display your selected content from syndicated RSS and Atom content feeds on your TV. The interface is designed for across-the-room use with the remote control. And this goes beyond just text content - audio and video-enhanced feeds are fully supported, truly delivering video on demand to subscribers. It’s designed as a companion to one of the other NewsGator editions, allowing you to access your content from wherever you are

Newsland - a free information service for the mobile devices brought to you by Newsland Ltd., an international company with headquarters in London and regional office in Moscow

NewsMob - a Web-based RSS News Aggregator which works with your existing Palm or Pocket PC web browser, sync or live, to provide you access to your favorite RSS Newsfeeds, anytime, anywhere

NewsMonster - offers a superior web experience and outstanding integration with existing websites and weblogs that support RSS. Even sites that don’t support RSS can work with NewsMonster. Runs on all machines running Mozilla 1.0, Netscape 7.0 or greater. (JavaScript must be enabled) Java 1.3 or greater and Java Web Start 1.2 or greater. OSX, Linux, or Windows

Newzie - more than a simple news aggregator. It offers different ways of monitoring things; it presents retrieved content in different shapes; it enables you to reach desired content fast. And all these interactions happen thru an exclusive user interface that you haven’t tasted yet in any other software application

nntp//rss -a Java-based bridge between RSS feeds and NNTP clients, enabling you to read your favorite RSS syndicated content within your existing NNTP newsreader. RSS feeds are represented as NNTP newsgroups, providing a simple, straightforward and familiar environment for news reading

Nokia 770 Internet Tablet - gives you instant wireless access to the Web. You can also stream files, tune in to Internet radio, read RSS feeds, or play your favorite videos and music

Oddpost - an award-winning web-based email application with an astounding news aggregator built right in

Odiogo - downloads your favorite RSS news and blog feeds and converts the text into spoken word - easily heard on your MP3 player, when and where you want. Simply select your feeds, click start, and then drag and drop the audio files into your MP3 player

Opera Web Browser - Starting with Opera 7.50, you can use Opera Mail to read RSS newsfeeds. Click newsfeed links to subscribe, or use Opera’s navigation bar while surfing to automatically recognize embedded newsfeed links and display a “Newsfeed” button

PHP RSS Feeder for PSP - Stream MP3’s from your PHP server with Dynamic RSS Channels on your Sony PSP 2.6+ with wi-fi from anywhere in the world

Planet - a flexible feed aggregator. It downloads news feeds published by web sites and aggregates their content together into a single combined feed, latest news first. It uses Mark Pilgrim’s Universal Feed Parser to read from RDF, RSS and Atom feeds; and Tomas Styblo’s templating engine to output static files in any format you can dream up. Requires Python 2.2 or greater

Planet Express - a Python script that uses a blog as the public interface for the feed aggregator. Requires Python 2.1

Python Desktop Server

Quick News for Palm OS - Requires Palm OS 4.0 or greater. Free 30-day trial

Raissa - an RSS headlines and news reader for the Newton MessagePad running NewtonOS 2.0 and higher. It should read RSS 0.91 and 1.0 sources

rawdog - an RSS Aggregator Without Delusions Of Grandeur. Written in Python, it uses Mark Pilgrim’s feed parser. It runs from cron, collects articles from a number of feeds, and generates a static HTML page listing the newest articles in date order. It supports per-feed customizable update times, and uses ETags, Last-Modified, and gzip compression to minimize network bandwidth usage

RDF-Ticker - a newsticker application which fetches news from RDF/RSS-feeds and displays them on a ticker-bar. These feeds are based on a special XML-format, which lets client applications show them in any convenient way for the end-user. The application runs as a ticker-bar in MS Windows®, which is by default always visible at the top of your desktop and takes only a small area of your desktop to display. Other applications don’t cover it, so you always have the news displayed in the foreground

Roosster - a free service that wakes you up to the most interesting information on the web - direct to your desktop via the popular RSS format. Hence the name RooSSter

RSS Feeds via JavaScript - makes use of a PHP script that parses the XML feed, and returns a JavaScript set of write commands that insert the information into your page. All you need to do is to insert a simple JavaScript line of code in the part of your page where you want the feed. The only other thing to tidy it up is to link or insert a sytle sheet to format the output

RSS News JavaScript Ticker - This version of JavaScript Ticker can show news from any RSS feed. Also, each news is presented as a link, so user can click to the source of the news

RSS News JavaScript Vertical Ticker - This version of JavaScript Ticker can show news from any RSS feed in a vertical scroller. Also, each news is presented as a link, so user can click to the source of the news

RSS News (Combo) JavaScript Ticker - This version of JavaScript Ticker can show news from multiple RSS feeds. The ticker grabs news from a number of RSS feeds and starts outputting RSS feed title followed by a customizable number of news titles from that specific feed, followed by title and news from next feed, so on. Each news is presented as a link, so user can click to the source of the news. Also, the title of each feed is presented as link. If no link is available for any, simple text id displayed

RSS Merge - Typically, printing several RSS feeds from various blogs on a single page is known as aggregation. This script not only aggregates RSS feeds however, it also merges and sorts them by date using the merge sort algorithm. The result is a blog of postings from several blogs

RSS Mix Tape - reads items from RSS feeds that you specify, and displays them in a list. You go through the list, picking your favorite posts and putting them into categories. You can also write comments on posts. Then you click the “Generate RSS” button, and RSS Mix Feed spits out an RSS feed for each category. Your friends can use their favorite RSS reader to view your feeds (livejournal is an RSS reader, if you’re a paid user). In short, RSS In, RSS Out. Requires Python, PyQT, PyKDE, and Python’s xmlbase

RSS Viewer - a Java-based ticker application. It uses JAXP to parse RSS-sites (RDF site summary). It is easy to use and easy to configure. It has 2 different views: a browser-like view and a simple ticker-view

RSSHome.com - a service for reading RSS feeds from mobile devices and desktop browsers

RSS2iCal - by Dean Sanvitale - View and/or Subscribe to RSS/RDF News Feeds in iCalendar (vCal 2.0) format

RSSinclude - Enter the URL address of the RSS feed you would like to integrate and copy a piece of HTML into your website. Thats all. Nothing more is needed to display any RSS feed on your website. RSSinclude service will do all the work

Safari RSS - Scan all the latest news, information and articles from thousands of your favorite major news organizations, community web sites and personal weblogs in one simple-to-read, searchable article list using Safari RSS

Sage - a lightweight RSS and ATOM feed aggregator extension for Mozilla Firefox. It’s got a lot of what you need and not much of what you don’t

Saki - socially interactive mobile software. Users can create profiles, upload pictures, write reviews, and send party invitations straight from their device. Saki enables you to meet new people, browse by location, by interests, and by school. Saki comes with a variety of premium applications bundled in one package. Programs include, avatar based IM, a real-time RSS reader, interactive themes, and custom widgets for your weather, stocks, and e-mail. Repetitive PC-to-device synchronization is not necessary. Saki offers advanced over-the-air (OTA) updates so you can receive the latest information without the hassle of cords

SaTiMoz - an RSS reader for Mozilla using the latest technologies to browse, read and store feeds

Straw -a desktop news aggregator for the GNOME environment. Its aim is to be a faster, easier and more accessible way to read news and blogs than the traditional browser

Sunrise - converts websites and newsfeeds for offline reading on your handheld

TickerMyFeed.com - add fresh content and breaking news to your website

Trillian Pro Plugin - implements RSS 0.9x news feeds and alerts

WebNews.TV - downloads the latest news from RSS news feeds and Web sites and then shows and pronounces them in TV like screen. Funny characters (for example - penguin) entertain you while you are reading and listening news headlines. For each news theme (world news, sports, technology, entertainment, etc.) you get different emotion of TV dictor (character) represented by special cartoon movie corresponded to this theme

RSS Feed Search

 mars 6, 2008 • Pas de commentaire

RSS Feed Search

    Feeds By Topic

    Blogs

    News

    Media Feeds

    Podcasts

    Video Blogs

    Video Aggregators

    Jobs

    Matrice de services autour du RSS

     mars 6, 2008 • Pas de commentaire

     rss-about.gif

    http://www.bloglines.com
    http://newsgator.com
    http://www.feedfeeds.com
    http://www.feedbucket.com
    http://www.google.com/reader/
    http://www.mediatuner.com
    http://rssor.utblog.com
    http://www.yodpod.com
    http://online1.attensa.com
    http://www.xprssit.com

    http://rss2pdf.com
    http://rssfunnel.com
    http://feedsifter.com
    http://www.feedfindings.com
    http://www.rsswatcher.com
    http://www.feedrinse.com
    http://www.feedburner.com
    http://www.rapidfeeds.com
    http://feedlounge.com
    http://www.feedshow.com
    http://www.feedpublish.com
    http://www.mysyndicaat.com
    http://feedcatch.feedshake.com
    http://www.talkr.com
    http://www.speakwire.com
    http://www.read.io
    http://www.odiogo.com
    http://www.feed2podcast.com
    http://www.reminderfeed.com
    http://www.beeplet.com
    http://futuremail.bensinclair.com
    http://feedjumbler.com
    http://groups.blogdigger.com
    http://www.feedcombine.co.uk
    http://feedblendr.com
    http://frankenfeed.com
    http://www.feedshake.com
    http://blogsieve.com
    http://feedpile.com
    http://www.rssmix.com
    http://www.kickrss.com
    http://www.rssdj.com
    http://www.yutter.com
    http://www.r-mail.org
    http://www.rssfwd.com
    http://www.shootthebreeze.net/blogalert/
    http://www.feedlinx.com
    http://www.queoo.com
    http://squeet.com
    http://www.bloglet.com
    http://www.feedblitz.com
    http://jade.mcli.dist.maricopa.edu/feed/
    http://www.feedostyle.com
    http://www.rss2html.com
    http://sandbox.sourcelabs.com/skinnerbox/
    http://www.magic-rss.com
    http://www.tickermyfeed.com
    http://www.rss-info.com/en_rssinclude.html
    http://www.feedroll.com/rssviewer
    http://feed43.com
    http://www.ponyfish.com
    http://feeds2.be
    http://feedyes.com
    http://www.diffbot.com
    http://www.wotzwot.com/rssxl.php
    http://www.feedxs.com
    http://www.feedcraft.com
    http://publi.sh
    http://skinnyfarm.com
    http://www.sabifoo.com
    http://socialmail.biggu.com
    http://www.mail2rss.org
    http://quickmail.johanfitie.com
    http://www.feed-mail.com
    http://dodgeit.com
    http://www.feedmailnow.com
    http://feedcrier.com
    http://instantfeed.biggu.com
    http://immedi.at
    http://www.rasasa.com
    http://www.feedbite.com
    http://share.opml.org
    http://www.opmlmanager.com
    http://zaptxt.com
    http://www.linkrss.com
    http://rojo.com/feedshare/

    Web sémantique - XML, RDF et OWL

     mars 6, 2008 • Pas de commentaire

    RDF apporte une infrastructure de données pour le Web

    RDF (Resource Description Framework) est un standard permettant la mise en place de descriptions simples. XML est à la syntaxe, ce que RDF est à la sémantique : un ensemble clair de règles permettant des informations descriptives simples. RDF Schema permet ensuite de combiner ces descriptions en un seul vocabulaire. RDF est intégré dans une variété d’applications comme :

    • catalogues de bibliothèques
    • annuaires internationaux
    • syndication et agrégation de nouvelles, de logiciels et de contenus
    • collections personnelles de musiques, de photos et d’évènements

    Dans chacun de ces cas d’utilisation, XML est utilisé comme une syntaxe interchangeable. Les spécifications RDF fournissent un environnement de travail puissant pour l’échange des connaissances sur le Web.

    « RDF représente une étape fondamentale dans la montée en puissance du Web. Nous allons enfin voir des applications qui combinent les informations provenant de sources multiples représentées en RDF, ce qui était totalement impensable jusqu’à présent, » explique Brian McBride, animateur du groupe de travail RDF Core du W3C, « Le groupe de travail RDF Core a permis aux spécifications RDF de se placer comme le fondement à la fois pratique et mathématiquement précis sur lequel OWL et le reste du Web sémantique pourront se construire. »

    OWL fournit des ontologies opérationnelles pour le Web

    La prochaine étape est de mettre en place une manière de développer des vocabulaires spécifiques à un sujet - ou un domaine. C’est le rôle d’une ontologie. Une ontologie définit les termes utilisés pour décrire et représenter un champ d’expertise. Les ontologies sont utilisées par les personnes, les bases de données, et les applications, qui ont besoin de partager des informations relatives à un domaine bien spécifique comme, la médecine, la fabrication d’outils, l’immobilier, la réparation d’automobiles, la gestion de finances, etc. Les ontologies associent les concepts de base d’un domaine précis et les relations entre ces concepts, tout cela d’une manière compréhensible par les machines. Elles encodent la connaissance d’un domaine particulier ainsi que les connaissances qui recouvrent d’autres domaines, ce qui permet de rendre les connaissances réutilisables.

    OWL - langage d’ontologies Web - est un langage permettant de définir des ontologies Web structurées, et ce faisant, autorise une intégration plus riche et garantit l’interopérabilité des données au travers des frontières applicatives. Les premiers langages utilisés pour le développement d’outils et d’ontologies pour des communautés d’utilisateurs spécifiques (particulièrement en sciences et dans des applications d’e-commerce spécifiques à certaines entreprises) n’ont pas été définis pour être compatibles avec l’architecture du Web en général, et du Web sémantique en particulier.

    OWL répare ce manque en utilisant à la fois les URIs pour nommer, et la fonctionnalité fournie par RDF pour créer des liens. Ainsi, les ontologies Web possèdent les avantages suivants :

    • Capacité d’être distribuées au travers de nombreux systèmes
    • Mise à l’échelle pour les besoins du Web
    • Compatibles avec les standards Web pour l’accessibilité et l’internationalisation
    • Ouvertes et extensibles

    OWL s’appuie sur un modèle et un schéma RDF pour ajouter plus de vocabulaire dans la description de propriétés et de classes, comme par exemple : les relations entre classes (i.e. la séparation), la cardinalité (i.e. « un et un seul »), l’égalité, une typographie plus riche des propriétés, des caractéristiques de propriétés (i.e., la symétrie), et des classes énumératives.

    « OWL constitue une avancée importante dans la représentation et l’organisation des connaissances disponibles sur le Web. OWL réussit à établir un bon équilibre entre les besoins de l’industrie pour un langage prenant en compte leurs cas d’utilisation du Web, et les restrictions imposées par les connaissances et les expériences de la recherche dans le développement d’un langage d’ontologies, » expliquent Jim Hendler et Guus Schreiber, co-animateurs du groupe de travail Web Ontology du W3C. « La cinquantaine de participants du groupe de travail ont conçu avec brio un langage qui souscrit aux préoccupations communes, et qui soit épaulé aussi bien par les académiques que par les professionnels. »

    Redland RDF Libraries

     mars 6, 2008 • Pas de commentaire

    Redland is a set of free software libraries that provide support for the Resource Description Framework (RDF).

    The Redland library packages are:

    These are mature RDF packages developed since 2000 used in several projects. Each library has it’s own documentation and status information in the form of a list of TODOs/bugs, general news, detailed release notes and file-by-file changes in the ChangeLog.

    License

    All Redland packages are free software / open source software and released under the LGPL 2.1, GPL 2 or Apache 2 licenses as alternatives. See the individual package license files for full details and any exceptions.

    Help and Support

    The Redland mailing lists can be used to discuss the development and use of Redland, Raptor and Rasqal as well as hear about future plans and get the first release announcements. There is also an #redland IRC channel on the freenode IRC network irc.freenode.net. For other license and support options, contact Dave.

    RDF pour nous autres

     mars 6, 2008 • Pas de commentaire

     www2007-exhibit.pdf

    http://people.csail.mit.edu/dfhuynh/research/papers/www2007-exhibit.pdf

    RDF offre à la fois une grande flexibilité et une grande interopérabilité pour publier ses données. Cette interopérabilité ne signifie pas juste que vos données fonctionneront avec les outils existants, ou de pair avec d’autres données dans le même format, mais qu’elles peuvent réellement être connectées à d’autres données à travers le Web. C’est ce qu’on appelle le Web sémantique, ou le Web des données : tout comme HTML pour connecter ses pages à d’autres pages sur le Web, RDF permet de lier ses données à d’autres données sur le Web. Fantastique.

    Qu’est-ce que RDF ?

    Les initiales RDF correspondent à « Resource Description Framework », ou cadre de description de ressources en français. Une ressource est simplement une chose. Une personne, un livre, un clavier, un article de blog, un aquarium, une idée, toute chose que l’on peut décrire. RDF est un cadre d’applications (N.d.T. framework) utilisant l’architecture du Web pour décrire une ressource. Tel HTML qui permet de relier des documents à d’autres documents sur le Web, RDF permet de relier une ressource à d’autres ressources sur le Web.

    Toutes les données RDF ont la même forme

    Lorsqu’on dit que toutes les données RDF ont la même forme, cela ne veut pas dire qu’elles sont toutes pareilles. RDF est un modèle de données, plutôt qu’un format, qui de ce fait peut être publié dans une grande variété de formats différents, en XML, JavaScript Object Notation (JSON), HTML et en texte ordinaire. Ce qui est important c’est qu’ils traduisent tous la même structure de base : le triplet. RDF consiste en déclarations simples appelées triplets. Un triplet se compose d’un sujet, d’un prédicat et d’un objet.

    Qu’est-ce qu’un triplet RDF ?
    • Le sujet représente la chose (ressource) sur laquelle porte la déclaration, et c’est toujours un indicateur de ressource uniforme (ou adresse URI) ;
    • Le prédicat est le nom d’une propriété de la ressource (tel que le nom d’un champs d’enregistrement de base de données), et c’est toujours une adresse URI ;
    • L’objet est la valeur de cette propriété, qui peut être une adresse URI ou un littéral (texte, nombre, date, etc.)

    Chaque triplet énonce : cette ressource a telle propriété, laquelle est soit une valeur littérale, soit une autre ressource (représentée par l’adresse URI).

    Utiliser RDF : une application hybride RDF simple avec Exhibit

    Exhibit est un cadre d’applications JavaScript configurable pour fabriquer des présentations à partir de données en petites ou moyennes quantités. Il peut importer du RDF/XML (la syntaxe XML normalisée de RDF) au travers du service Web de Simile qui le traduit dans le format JSON d’Exhibit, lui-même une version de RDF. Fabriquer une application hybride (N.d.T. mashup) est simple :

    1. Copiez-collez (et personnalisez si besoin) ce modèle-ci ;
    2. Éditez les éléments <link rel="exhibit/data" /> afin qu’ils pointent vers les données à utiliser, où qu’elles se trouvent sur le Web ;
    3. Chargez la page dans votre navigateur. Ça y est.

    Vous trouverez d’autres instructions sur la fabrication des applications Exhibit sur le wiki de Simile.

    Conclusion

    RDF est le langage de base du Web sémantique. Cela veut dire que, par la publication de vos données en RDF sur le Web, par l’utilisation des termes de vocabulaires existants là où c’est possible et par la liaison à d’autres données, vous pouvez augmenter l’utilité des données reliées comme celle des vôtres. Il y a de plus en plus de données RDF disponible sur le Web. Le wiki Linking Open Data en liste quelques sources.

    Mais même sans le Web sémantique qui est plus vaste, la flexibilité et la structure uniforme de RDF en font une forme très utile pour tenir vos données. Vous n’avez pas non plus besoin d’attendre que tout le monde le fasse, vous pouvez l’utilisez aujourd’hui.

    Liens utiles

    Outils

    Données

    Plus d’informations

    • eRDF : la spécification eRDF avec des exemples et des explications
    • Une page wiki à propos d’eRDF : liens vers des outils, des exemples et des tutoriels pour eRDF
    • RDFa est la syntaxe officielle du RDF dans HTML du W3C. Très proche d’eRDF, elle offre une syntaxe plus puissante au prix d’une plus grande complexité et nécessite de nouveaux attributs
    • Les microformats sont des représentations sémantiques conventionnelles de certains types d’informations en (X)HTML. Ces informations sont transposables en RDF via GRDDL
    • GRDDL est une spécification décrivant comment un document peut déclarer une feuille de style XSLT (ou un autre script de transformation) grâce à laquelle on peut en extraire du RDF
    • Get Semantic est une communauté de discussion et de promotion de diverses approches du HTML sémantique
    • Comment publier des données liées sur le Web

    Keith Alexander est un toxicomane du balisage de données qui aime les technologies du Web sémantique, rêver le jour et courir après l’insaisissable « Big Foot ».

    Notes
    1. RDF For The Rest Of Us / Digital Web Magazine ↑

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