Alexandre Passant

I gave a talk on "Using Semantics to Improve Corporate Online Communities" yesterday at the COIN@MALLOW workshop. The talk was mainly based on the work done during my Ph.D. thesis, demonstrating how to manage and combine various layers of semantics on the top of Enterprise 2.0 ecosystems and let users create and take advantage of the related semantic annotations. Here are the slides of the talk.

I'm happy to announce CommonTag, a new RDFS vocabulary for Semantic Tagging, designed to bridge the gap between free-text tagging and Linked Data. In a similar way that what I've done in the past with MOAT, CommonTag allows one to create links between his tags (as simple keywords) and the concept they represent, defined as URIs of Semantic Web resources, from public knowledge bases such as Freebase or DBpedia.

What is especially relevant with regards to CommonTag is that the vocabulary aims to be simple to understand, easily accessible, and with an easy RDFa annotation process for end-users and Web developers. On the other hand, it features mappings with existing tagging vocabularies (the Tag Ontology, MOAT, SCOT, SIOC and SKOS) for those who want to go further or use their existing applications with this new model.

But most interestingly, as one can see when browsing the website, a key feature is that CommonTag is not an isolated initiative but supported by various companies involved in the Semantic Web and the Social Web -- and especially in both ! -- namely (for the initial nucleus and by alphabetical order, hope it will grow soon !) AdaptiveBlue, DERI (NUI Galway), Faviki, Freebase, Yahoo, Zemanta and ZigTag - and I must add that was a great experience to design this vocabulary together !

CommonTag is already supported in various applications as you can see on the website and on the following picture, from Zemanta to index your blog posts to Sindice to build applications on the top of it. And there is more to come soon, stay tuned ;-)

Je soutiendrai ma thèse "Technologies du Web Sémantique pour l'Entreprise 2.0" le mardi 9 Juin à 10h30 à la Maison de la Recherche, 28 rue Serpente, Paris.

Résumé:

Les travaux présentés dans cette thèse proposent différentes méthodes, réflexions et réalisations associant Web 2.0 et Web Sémantique. Après avoir introduit ces deux notions, nous présentons les limites actuelles de certains outils, comme les blogs ou les wikis, et des pratiques de tagging dans un contexte d'Entreprise 2.0. Nous proposons ensuite la méthode SemSLATES et la vision globale d'une architecture de médiation reposant sur les standards du Web Sémantique (langages, modèles, outils et protocoles) pour pallier à ces limites. Nous détaillons par la suite différentes ontologies (au sens informatique) développées pour mener à bien cette vision : d'une part, en contribuant activement au projet SIOC - Semantically-Interlinked Online Communities -, des modèles destinés aux méta-données socio-structurelles, d'autre part des modèles, étendant des ontologies publiques, destinés aux données métier. De plus, la définition de l'ontologie MOAT - Meaning Of A Tag - nous permet de coupler la souplesse du tagging et la puissance de l'indexation à base d'ontologies. Nous revenons ensuite sur différentes implémentations logicielles que nous avons mises en place à EDF R&D pour permettre de manière intuitive la production et l'utilisation d'annotations sémantiques afin d'enrichir les outils initiaux : wikis sémantiques, interfaces avancées de visualisation (navigation à facettes, mash-up sémantique, etc.) et moteur de recherche sémantique. Plusieurs contributions ont été publiées sous forme d'ontologies publiques ou de logiciels libres, contribuant de manière plus large à cette convergence entre Web 2.0 et Web Sémantique non seulement en entreprise mais sur le Web dans son ensemble.

La soutenance est publique, si le sujet vous intéresse, n'hésitez pas !
Le mémoire et les slides seront également postés sur ce site par la suite.

A follow-up to my previous LODr introduction post, and as you might guess with the title, one more way to show the value of RDF-based applications in general. Or more precisely, open-RDF-based and LOD-compliant:

• By open-RDF-based, I mean using RDF but also publishing it, eitheir through a SPARQL endpoint, Semantic sitemaps or RDFa. What I want to focus on here is that using RDF 'inside-only' doesn't make your service be part of the Semantic / Linked Data Web, while it can indeed be considered as Semantic-Web based - I hope that's clear enough. If you don't expose anything, you can have the better RDF infrastructure that you want, you will still be a Web-of-Documents application. (Some related thoughs here);
• Regarding LOD-compliance, I refer to reusing or interlinking existing resources in order to benefit from it within your application. The value of your service can then reside not only on the data you provide, but on the way you interact with - and reuse - other datasources. Moreover, this can also concern corporate environments.

What I want to stress in that post is how such applications can become components of a general infrastructure (the Semantic Web itself) that will provide new services to end-users. Especially, regarding LODr, it lets users interlink popular Web 2.0 content to Semantic Web resources and such interaction can then be used for data discovery. For instance, the following query will retrieve all Slideshare presentations related to the Semantic Web, i.e. linked to a resource that is itself linked to the SW category in DBpedia. This query involves various vocabularies, as SIOC (to retrieve the item), FOAF (its author), the Tag Ontology (its tags), MOAT (tags meanings) and a DBpedia URI as an entry point to find related topics.

SELECT DISTINCT ?item ?author ?date ?tag ?meaning
WHERE {
  ?item a sioc:Item ;
  dct:created ?date ;
  sioc:has_space <http://slideshare.net> ;
  foaf:maker ?author .
  [] a tags:RestrictedTagging ;
    tags:taggedResource ?item ;
    tags:taggedWithTag [
      tags:name ?tag .
    ] ;
    moat:tagMeaning ?meaning .
  ?meaning ?p <http://dbpedia.org/resource/Category:Semantic_Web> .
}
ORDER BY DESC(?date)
LIMIT 5

You can browse the answer here, formatted in HTML.

Of course, the URIs that you can use in LODr and with MOAT in general are not restricted to DBpedia ones. You can use URIs defining some of your friends, conferences you attended, etc. Consequently, those URIs can be used in queries patterns, as well as other interlinked URIs. For instance, the following one will retrieve all pictures from Flickr linked to an event that happened in Tenerife, and in that case it will use the ESWC2008 URI, going through some Geonames data:

SELECT DISTINCT ?item ?author ?date ?tag ?meaning
WHERE {
  ?item a sioc:Item ;
  dct:created ?date ;
  sioc:has_space <http://flickr.com> ;
  foaf:maker ?author .
  [] a tags:RestrictedTagging ;
    tags:taggedResource ?item ;
    tags:taggedWithTag [
      tags:name ?tag .
    ] ;
    moat:tagMeaning ?meaning .
  ?meaning foaf:based_near <http://sws.geonames.org/2522437/> .
}
ORDER BY DESC(?date)
LIMIT 5

Answer

Finally, while all those queries involve the lodr.info endpoint, each LODr intance comes with its own triplestore (and related endpoint), so that one can add some more RDF in it for advanced mash-ups. And as it also provides RDFa and semantic sitemap support, semantic web crawlers and indexes as SWSE or Sindice can also consume it and then deliver it when you look for a particular URI.

In one of my recent post, I mentionned LODr, a semantic-tagging application based on MOAT. While I started it a few months ago, it's finally online now. I put the code in svn last friday and twitted about it, but did not make any official announcement yet, so here it is. I certainly should have released before, but as the source code involves lots of classes, I wanted to be sure of the architecture.

So, what is it about ?

LODr aims to apply to MOAT principles (in a few words, link your tags to concepts URIs - people URI, Musicbrainz artists, DBpedia resources ... - , share those relationships in a community and then tag content with those URIs) to existing Web 2.0 content. So you can "re-tag" your existing Flickr pics, slideshare presentations, etc, using those principles and make your social data enter the LOD cloud. I think focusing on the existing word is important here, as LODr lets you keep your Web 2.0 habits by using your favourite tools, but provides a separate service to semantically-enrich it. I don't want to go into too much details here, but in brief, some interesting points regarding the applications are:

• While tags / URIs relationships are shared within the LODr community in a central RDF-base (following the MOAT architecture principles), LODr is a personal application, so that you just need to install the software on your webserver to enjoy it. Moreover, as it's local, you can re-use your data immediately for any mash-up;
• LODr is completely RDF-based. It might be a bit geeky, but as some were recently wondering where are all the RDF-based applications, here's one. And of course RDF-based means using standard vocabularies, such as SIOC, FOAF, DC, the Tag Ontology and of course MOAT. The RDF-backend is powered by ARC2, so you can enjoy a SPARQL endpoint for your data. Last but not least, each item page features RDFa, using the previous vocabularies, even if you decide not to use MOAT for a particular item (so that any Web 2.0 item you aggregate is RDFa-ized);
• Aggregated data will provide you a complete tagcloud for your social activity (which might be SCOT-ed in the next updates), as seen here. Each tag link redirects to a list of items provided using Exhibit, and you can restrict by source (i.e. the service it's from) or creation date. And if a tag have been assigned a URI, you'll get a link to browse the related items using a similar interface;
• When browsing all items tagged with a particular URI, you'll get suggested some related URIs. Related because of co-occurence as usually in tag-based applications, but also because they're directly interlinked, or because they share a common property. To avoid information overload, only the URIs you used to re-tag some of your items will be shown;
• The application can be easily extended. LODr uses wrappers to retrieve your data, and each wrapper is only a few lines of code (e.g. 24 lines for the Flickr one). At the moment, wrappers use RSS to retrieve data and the feeds are automatically discovered from the user FOAF profile - dataportability rocks ! Yet, the architecture allows to use authenticated wrappers (to use services API) but also SIOC exports for those tools;
• As the MOAT process is more time-consuming that simple tagging (since you must define tag/URI relationships, at least at the first time as you can do automated tagging after) the URIs can be displayed as labels when you need to choose which one is relevant for your tag (using the inference capabilities described here as not all resources have a direct rdfs:label property ) . When you need a new URI, the application relies on the Sindice search widget, as done in the Drupal MOAT module. And the system then checks if the new URI is valid, but I'll blog about that particular point later;
• Finally, in addition of the previous features, LODr can be used to discover all the community content. This feature is not provided by the local application, but by LODr.info, that aggregates your RDF data when you re-tag it to provide search capabilities. Then, you can directly list all items linked to a particular URI. Want to find content related to the Forbidden City ? Or to SPARQL ? And to be even more enjoyable, I added a Ubiquity command so that from any Wikipedia page (more services will be supported soon), you can get the list of all related items (through DBpedia in order to find the concept URI from a document page). While it provides a really-straightforward way to discover related Web 2.0 content when browsing the Web, I also hope it can convice people of the complete process.

So, you can simply download the code from the website and install it. For those who just want to have a look, you can check my LODr instance (while you won't be able to edit it, you can check the display interfaces). As there might be some bugs and I'm still adding features, please consider using the SVN version instead of the tgz. And then, enjoy the power of Linked Data for your Web 2.0 content ;-)

No much time to blog at the moment, as I'm mainly concentrated on writing my PhD thesis (and so I wish best of luck - and motivation - to the ones in the same case !)

I finally uploaded the slides of the various talks I gave at last ES(W)C in Tenerife:

• "FOAF and SIOC applications", invited talk at Harry Halpin's "Social Networks" tutorial (embeds at the end of that post)
• "MOAT: Meaning Of A Tag", lightning talk at the LOD BOF

Mercredi, jeudi et vendredi (18-19-20 Juin) auront lieu à Nancy (au LORIA plus pécisément) les 19e Journées Francophones d'Ingénierie des Connaissances, IC2008.

I'm currently in Beijing, enjoying WWW2008.

Sunday, Uldis, John and myself gave a tutorial about "Interlinking Online Communities and Enriching Social Software with the Semantic Web", in which we detailed current state of the art regarding SIOC and related works, like how Enterprise 2.0 or data portability can be enhanced thanks to the Semantic Web, as well as describing various tools that produce or consume Social Semant

I just commited two updates for the MOAT module for Drupal 5:

First, in order to add new URIs for a tag, the plugin now uses the sindice Widget that will query Sindice.com and suggests URIs for the used keyword. Then, simply chose the URI, and it will be added as a new meaning for your tag.