Archive for the ‘Linked Data’ Category

Interview with New Scientist on Linked Data

Monday, May 19th, 2008

Last week, i was sent an email by Jim Giles , a freelance writer for the New Scientist based in San Francisco. He asked if i could spare a few minutes to give my views on -->Linked Data --> and DBpedia and, in particular, if these initiatives will bring the Semantic Web to the masses. I was reluctant at first, not least because there are other people in the Linked Data world who could enthuse and evangelise a lot more than i could. However, after deferring to Hugh we decided we should respond and Hugh would do the interview.

I then found out that the interview would be on Skype so i could join in the conversation, even as a passive participant. Amazingly, I have never used Skype before and was worried about not having a special headset to use on my laptop. As it turned out the call quality was very good and we ended up having over an hour’s discussion that was conducted mainly between Jim Giles and Hugh ,although i was able to contribute in some places.

Hugh started off by setting the -->Linked Data --> intiative in the context of Semantic Web research that has been ongoing for many years. Hugh commented that he thought the Semantic Web would arrive without everyone neccessarily knowing that it had, and Semantic Web researchers would be slightly annoyed that all their efforts had not got the recognition they deserve. This situation is wuite likely since so called semweb apps such as Twine ,Garlik and Powerset don’t come across to the average user as being anything over than a standard Web or Web 2.0 application.

The interview then moved on to the topic of coreference and how it is a problem that needs to be overcome in order for Linked Data clients to successfully gather and use the knowledge that’s out there. It took some explaining, but in the end Jim realised the way in which the LOD bubbles linked together and where coreference arises. Jim then asked for an example of an application that could use Linked Data and provide value to a user that was not already provided by Web 2.0 apps. I pointed out the DBpedia Mobile application that was presented at the LDOW Workshop. The ability to mesh data from different sources in a standard way without being tied down to a specific application is really the main selling point of Linked Data. Having explained the advantages, we were then asked how this technology will become mainstream. I gave links to the BBC’s Linked Data work and the London Gazette to indicate that Linked Data is already being used in big companies and organisations and the number will only continue to grow. Jim was impressed by this and said he would chase up the guys at the BBC to investigate their work.

As a final comment from Hugh the divergence in Semantic Web research was highlighted. We can see two main camps emerging: the ontology or ‘formalists’ camp and the technology or ‘pragmatists’ camp. It seems increasingly clear that one may view the other with a certain amount of disdain. This is picked up in our weekly Semantic Web Interest Group meetings at ECS.

We have no idea what the final article will look like and how much of our converstion will be used but it was good to hear from someone outside of the normal Semantic Web Gang getting interested in Linked Data.

Triplification failure

Wednesday, May 14th, 2008

I was trying to add the triplify add-on for Wordpress to this blog. Unfortunately things didn’t go quite according to plan. Firstly, the documentation on the website is not very detailed particularly with regards to installation instructions. The instructions contained in the readme file in the download package were more helpful.

Secondly, there is no mention of the add-on only being compatible with PHP 5.1.x and higher. The problem occurs in the pdo package that is installed as standard in PHP 5 but not PHP4. This package is used to manage database connections to a range of databases including MySQL and PostgreSQL. After hunting down a PHP4 compatable version of PDO i thought things might fit together. However, after hacking around with a PHP4 PDO class i started getting curious hebrew error messages:

PHP Parse error: parse error, unexpected T_PAAMAYIM_NEKUDOTAYIM, expecting ',' or ';' in /home/.../triplify/PDOStatement_mysql.class.php on line 42


‘Paamayim Nekudotayim’ as it turns out is Hebrew for ‘double colon’, an error message left by PHP’s israeli authors.

So my attempt to add this blog to the Linked Data world were unsuccessful. It is also hard to upgrade to PHP5.2 since uses Red Hat Linux Enterprise and there is currently no rpm available for this distro. At least the SIOC plugin seems to be working and should be useful if i decide to manually export the data of this blog as Linked Data.