Alexandre Passant

Edit 10/02/2010: There was a few bugs in that release, please consider downloading the v2.2.1

One more week, one more release, here's SMOB v2.2. This one fixes a few bugs (apparently the #tag tabs where unavailable on the 2.2 due to a bug I introduced in the .js file) and provides the following new features:

• geolocation of microblog messages (see example below), which shows one more benefit of the LOD cloud, as coordinates of posts are provided thanks to the GeoNames integration and OPO;
• ability to delete messages (deletion being then propagated to other hubs using SPARQL/Update) and to automatically purge messages older than X days (mainly to keep the DB lightweight - starred messages are not removed);
• on-demand creation of FOAF profile, in case one wants to try SMOB but does not have one (or does not want to provide it);
• parser for hyerlinks in microblog posts; and
• updated installer, allowing to select if SMOB should be used as a Twitter client (read / write settings).

BTW, as for the previous updates, you have to remove your config file and re-do the install procedure, and it will not remove your existing messages.

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 had a chat yesterday on Skype with Henry, wondering how FOAF-SSL applications would react on the following scenario:

• My personal URI redirects to a document about myself using a 303 redirect;
• This document is not a native RDF/XML or turtle file, but an XHTML documents embedding RDFa annotations.

Indeed, the current FOAF-SSL online certificate generation tool relies only on personal URIs (or WebID if you prefer) that corresponds to fragments of RDF documents, as in http://example.org/foaf.rdf#me. However, it shouldn't be an issue for the clients, since most recent Semantic Web applications should be able to deal with such scenarios of redirect and RDFa. And indeed, it worked perfectly - at least on the two FOAF-SSL clients that I tried with Firefox (something wrong in Safari not asking for any certificate)

It took me only a few minutes to set-up and try this complete use-case (well, actually a bit more to test it, until I discovered the Safari issue):

• Create my certificate and upload it in my browser using this tutorial;
• Generate the related RDFa snippet corresponding to the certificate, see below or in ESW Wiki;

<div about="#cert" typeof="rsa:RSAPublicKey">
  <div rel="cert:identity" href="http://apassant.net/alex"></div>
  <div rel="rsa:public_exponent">
    <div property="cert:decimal" content="65537"></div>
  </div>
  <div rel="rsa:modulus">
    <div property="cert:hex" content="8af4cb6d6ec004bd28c08d37f63301a3e63ddfb812475c679cf073c4dc7328bd20dadb9654d4fa588f155ca0
5e7ca61a6898fbace156edb650d2109ecee65e7f93a2a26b3928d3b97feeb7aa062e3767f4fadfcf169a223f4a621583a7f6fd8992f65ef1d17bc42392f
2d6831993c49187e8bdba42e5e9a018328de026813a9f"></div>
  </div>
</div>

• Add the cert and rsa namespace in my Drupal template header - even easier as I already have the other namespaces here, as well as GRDDL profile and correct DTD)
• Edit my about page (that is provided via the 303 redirection from my URI) with Drupal to add the RDFa snippet in it;
• Successfuly log-in to a test-page (that uses ARC2 - which natively supports that 303+RDFa scenarios, hence enabling that RDFa FOAF-SSL scenario) and in the Cheese lovers club; below is the output of the first one

It's now time for related applications, and I hope I'll be able to write more about it in the future.

It has been announcedin the past few weeks but I didn't really blog about it so far. We're hosting a second edition of the Social Data on the Web (SDoW) workshop at the next ISWC2009 in Washington. Here's the call for papers (longer version here).

The 2nd Social Data on the Web workshop (SDoW2009) co-located with the 8th International Semantic Web Conference (ISWC2009) aims to bring together researchers, developers and practitioners involved in semantically-enhancing social media websites, as well as academics researching more formal aspect of these interactions between the Semantic Web and Social Web.

Since its first steps in 2001, many research issues have been tackled by the Semantic Web community such as data formalism for knowledge representation, data querying and scalability, or reasoning and inferencing. More recently, Web 2.0 offered new perspectives regarding information sharing, annotation, and social networking on the Web. It opens new research areas for the Semantic Web which has an important role to play to lead to the emergence of a Social Semantic Web that should provide novel services to end-users, combining the best of both Semantic Web and Web 2.0 worlds. To achieve this goal, various tasks and features are needed from data modeling and lightweight ontologies, to knowledge and social networks portability as well as ways to interlink data between Social Media websites, leveraging proprietary data silos to a Giant Global Graph.

Following the successful SDoW2008 workshop at ISWC2008, SDoW2009 aims to bring together Semantic Web experts and Web 2.0 practitioners and users to discuss the application of semantic technologies to data from the Social Web.

The workshop welcome submission of short and full papers as well as demos of applications combining Semantic Web and Social Web technologies - all due to the 10th of August.

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 !)

The SDoW deadline have been extended to the 4th of August, so that you have two additional weeks to submit your paper, demo or poster.

The 1st Social Data on the Web workshop (SDoW2008) co-located with the 7th International Semantic Web Conference (ISWC2008) aims to bring together researchers, developers and practitioners involved in semantically-enhancing social media websites, as well as academics researching more formal aspect of these interactions between the Semantic Web and Social Media.  

Complete details about the wor

Today was my last day of work at EDF R&D.

Monday's DBpedia mobile presentation at LDOW2008 impressed me a lot. Actually, while I never worked on it, I'm really interested in ways to combine mobile applications, Semantic Web / Linked Data technologies and social networking.

Vendredi dernier avait lieu la seconde édition du SemanticCampParis.