Category: Semantics

Categories
RDF

Mind the Gap!

Recovered from the Wayback Machine.

rdfdata.org’s newest data source is The London Tube’s Schedule in RDF/XML. The data is used by the online tubeplanner.com.

Putting this data into RDF/XML is a wonderful idea. Can you imagine the possibilities if other London organizations started putting their events into an RDF/XML feed? Add yourself into the mix with FOAF, and a bit of glue such as a relationship defining ‘want to see’ and ‘want to attend’ and you have a way to pre-plan a trip to London, virtually at a click of the button.

I’ve been in London once, staying in a lovely hotel not far from Buckingham Palace. I found this hotel and got a nice deal through one of the online trip planners, I can’t remember which. But if this is thrown into the mix, and then add in plane reservation information (not to mention specials), you could arrange to get to London and back all at the click of a button. Just tell the system generally when you want to go, what you want to see, class of accommodations and flight and budget, and let it go to town.

If the data is present the technology now exists to not only schedule everything, but also print out several alternative itineraries, including Tube information coming and going from your hotel. Not only that, but the application could even print out maps of a certain size and format to fit into checkbook sized map holders with a clear plastic side, so that you can put all your maps into the holder, and then shift them as needed as you travel about.

You’d never get lost. You’d see everything you wanted to see. You’d spend what you want, but still get as close to the class of accommodation and flight you want. And you’d still have plenty of time just to wonder about and see the subtle aspects of London that seem to not get mentioned in Guidebooks.

Wait a sec – why not connect in Fodor and other guidebooks so that the system could recommend places that are similar to those identified in your ‘want to see’ relationship. That way you’ll see the Tate Modern, as well as the Tate Britain. Or that nice art gallery that had all the sketches of Botticelli’s Dante that inspired me to buy that huge book containing reproductions and a description of each.

And you have to eat, so why not describe in your FOAF file your likes and dislikes, whether you love Indian food, if you’re a vegetarian, and do you like to dress up for dinner. Then have the system suggest eating places near places your visiting. That way you can have time for a really nice Tea every day; because if you go to London and don’t have afternoon tea, you’ll miss one of the loveliest customs there is – skip lunch, go for Tea, eat dinner late. You’re in Europe, time to leave the Midwest 5pm supper at home.

Of course if you’re into spontaneity, you don’t need all of this. You grab a flight whenever it’s cheapest, throw your stuff in a backpack, land, find the nearest hostel and pub, meet the locals and then follow wherever the impulse leads you. Nice enough if you’re young, but when you’re a mature woman such as myself, hoping to connect up with locals in the pub just doesn’t have the same appeal it once had. Well, it does really; but there’s something seedy about a 50 year old woman going to a pub trying to connect up with the locals. Too bad really, but I’m not ready yet for the tour buses, either.

Besides, I’m all for have plenty of time to wonder around – but I don’t want to miss seeing both the Tate Britain and the Tate Modern, and having a lovely Tea in my beautifully situated and elegant hotel. And still have money left over to bring home a genuine London brolly.

Much of the work for all this has already been started, as you can see from Dan Connolly’s work and others.

Once London has been RDF’d, then we can turn to Paris, and New York, and Rome, and on and on. Interface all of this with PDAs and cellphones and I’m sure we could hook on to the iPod subculture in some way and quicker than Bob’s your uncle, you’ll have a piece of the Semantic Web, (that big letter one), based on bits of data borrowed from the semantic web (the ragtag one).

I’m ready to start. All I need now is venture capital money. Someone want to send me to London so I can ride the Tube, again?

Categories
RDF Specs

What is FOAF and why do you need it?

I thought I would break in with a little tech talk and discuss FOAF, or Friend of a Friend. If you hang around weblogging for any length of time, you’ll probably come across this term. Might be nice to know that it’s not some kind of new goverment regulation.

FOAF is XML created using a specific RDF (Resource Description Framework) vocabulary that allows you to provide a file with information about yourself, and basically, who you know. It’s the brainchild of Dan Brickley and I believe Libby Miller, and has its own support site and blog, though I’m not sure if the weblog is still being updated.

You don’t usually make a FOAF file by hand–either it’s created for you by your tools, or you can use the FOAF-a-matic, a handy forms-based tool that generates valid FOAF XML for you. You can then copy the contents into a file, named something like foaf.rdf, and put this file into the same location as your weblog. Some weblogging tools can do this for you, and you’ll need to check with yours to see if it does, or doesn’t manage FOAF files for you.

To enable people to autodiscover your FOAF file, you can then add the following into your primarily web page, in the HEAD section:

(Note, I had to remove the example because it was not showing up in the page, even with angle brackets being escaped. This most likely is a bug with the underlying tool implementation. The link to autodiscovery also shows the code.)

To see a badly outdated version of a FOAF file, you can check out mine.

Now that you have an idea of what it is, you might be wondering what’s it good for.

Some weblogging tools use FOAF files to auto-generate blogrolls for a weblog. Some people might consider this a goodness, but I’m not one of them. The reason why is that just because you know someone doesn’t mean you want to recommend to the world that they read them.

Others build libraries of photos and friends’ photos using FOAF and it’s image capability, which could be particularly useful for managing photos across many different web sites but based on the same event.

There has been talk of using FOAF to build a Web of Trust — to be able to state who you trust in FOAF and then a person knows based on this that they can also trust them. Though there has been a great deal of work on FOAF and privacy and accountability, the vocabulary isn’t there yet, and even the creators would be hesitant about recommending FOAF as it stands now to be used for a basis of trust.

There has also been discussion about extending the FOAF vocabulary to expand the types of relationships available. However the concern on this is the impact something like this could have, if one person considers you a friend and you put into your FOAF file that they’re just someone you know. And do we really want people to know whom we love, have birthed, work for, and so on? Sometimes. Sometimes not.

However, using relationships internally in an application, something such as an address book, could be very useful — but then why use FOAF, which is primarily used to create networks based on publicly accessible FOAF files.

Regardless of use and opinions about FOAF, it is now the second most widely dessiminated example of RDF/XML in use today, after RSS 1.0. And if you hang around weblogs, you’ll be stumbling across it at one time or another. More than that, the tools you use may be asking you whether you want a FOAF file or not.

Categories
RDF

Now that’s funny

Recovered from the Wayback Machine.

I haven’t been able to post much here because of the work on the Kitchen (BTW – it sure would be nice to see more technical people involved with this. Hint. Hint.)

Anyway, I don’t much care for IRC, but this snippet that Danny broke out of the FOAF IRC channel was extremely funny, and more than worth a link.

For those curious, smushing is a highly technical term meaning: squishing many FOAF files together. I believe.

Now squishing means…

Categories
RDF

Another from Slashdot-a replacement for SQL?

Recovered from the Wayback Machine.

Another entry from Slashdot, this one about an alternative to SQL, based on SQL guru Chris Date’s innovations in the field.

This alternative, known as ‘Tutorial D’, would seek to eliminate some of the more persistent relational DB problems, such as that pesky multi-meaning null. Is a field null because it makes no sense for data to exist in the field? Or is it null because no data has been provided yet? This has always been a killer in database design, and something the proponents of “Tutorial D” could resolve, among other things.

But before we throw out our MySQL and Oracle, the authors caution, take heed:

There’s a way to go, though. First off, there are still some unconquered faces on the mountain – the notes from a presentation by Darwen (see the Third Manifesto website) admit that the implementation of some of the new techniques is “something for the next generation of software engineers to grapple with”. The main problem, however, is that although SQL is clunky and, from a purist’s standpoint, just plain messy, it passes the usual business test – that is, it’s good enough to do the job that’s asked for it.

SQL is ubiquitous. For something that’s weak, fallible, and failing, it’s used everywhere; it’s a rare application that doesn’t use a relational database. This is something the ’s, w’ semantic webbers, (not to mention the RDF critics) should keep in mind: a technology, a model, or an implementation doesn’t have to be perfect to be useful.

Categories
RDF

Semanticweb meet Slashdot

Recovered from the Wayback Machine.

Interesting Slashdot thread about how Lehigh University is going to build the Semantic Web all by itself.

Computer scientist Jeff Heflin and others are building the Semantic Web, which they hope will handle more data, resolve contradictions and draw inferences from users’ queries. The new improved Web will also combine pieces of information from multiple sites in order to find answers to questions.

My reaction on reading this? Anyone that writes something like …are building _the_ Semantic Web, like it’s an object you can buy from Amazon, with easy to follow instructions doesn’t know beans about the ’small s, small w’ semantic web. It’s more than just the ontologies and the syntax, and more than technology. It’s about how to get people to buy into all of this. It’s about taking that same low cost to entry that allowed web pages to explode, and applying it to meaning as well as content. It’s about getting just plain Joe and Jane to go ‘cool’ and want to be a part of it–not just the geeks and science studs.

I do agree with the good doctor that we need to find a way to resolve contradictory ontologies, though I think we have the method for merging ontologies (i.e. RDF and OWL). But none of this matters if we can’t get buy-in to annotate data with meaning. So far, we’re not reaching beyond the science of the tech, to the people. And it’s more than the fact that all of this effort is young – it’s as if we see the non-tech as passive users of the semantic web, rather than active participants.

Sometimes I think that most people who work on the Semantic Web (the big letter fellow), don’t have a clue what it’s all about. It leads to wonder how much respect these folks have for those outside of their circles.

(This attitude, of course, being why I’m not on anyone’s Christmas Card list.)

The slashdotters get it:

The whole reason the web is popular is because it’s trivially simple to create content for it. Maybe the web would be more useful if it was like a giant encyclopedia but it’s just an exercise in futility unless everyone gets on board.