danbri’s foaf stories

Via momolondon list: opencellid.org data dumps

The readme.txt file describes the tabular data structure (split into a cells, and a measures file).

I think the cells data is the one most folk will be interested in re-using. Table headings are:

# id,lat,lon,mcc,mnc,lac,cellid,range,nbSamples,created_at,updated_at

For example:

7,44.8802,-0.526878,208,10,18122,32951790,0,2,2008-03-31 15:22:22,2008-04-07 08:57:33

This could be RDFized using something similar to the (802.11-centric) Wireless Ontology. Perhaps even using lqraps…

While I’m writing up old hacks, here’s one that I really enjoyed, even if it was a bit clunky. A couple of years ago Mikel Maron implemented (on my urging in irc.oftc.net #geo IRC :) a PHP-based Google Earth touring service, which interconnects a “tour guide” user with “tourists”.

This site facilitates collaborative, realtime exploration of Google Earth. As the “tour guide” navigates, “tourists” will automatically follow along.

When the tour guide’s Google Earth installation is at rest, a specially installed KML network link sends the server an HTTP request, showing the coordinates of the visible area of the globe. This same service is periodically polled (every second) by “tourists” whose Google Earth will dutifully fly to the appropriate spot.

The system seems to be offline currently, but was quite evocative to use, even if tricky. You never quite knew what the other party could actually see, since the picture can load quite slowly when moving around a lot. And the implementation didn’t do anything about angle of view (although this became possible in later versions of KML). I had experimental tours of Dublin guided by Ina (Skyping at same time), and of various places in Iran by Hamed Saber.

I expect in due course (if not already, I don’t track these things) Google Earth and similar products (Worldwind, or the Microsoft thingy) will offer social map browsing, it’s such a nice feature, though it really needs an audio channel open at the same time. Last week I tried to do the same without such a link, my mum talking me thru finding a small village in France. Much harder! “Take the road north out of Chabanais … past a small farm, past the swimming pool…”.

Here is Mikel’s “how it works” writeup:

The web interface generates KML files, which are loaded into Google Earth and create Network Links. The tour guide has a “View Based Refresh” Network Link, which sends the bounding box of the current view to the specified URL whenever the camera stops. That position is stored. Tourists receive a “Time Based Refresh” Network Link, which requests every 10 seconds and receives the last stored position of the guide.

Right now only location and altitude are transmitted. A future release of Google Earth may enable tilt and rotation. Integrated chat would be nice as well.

The fact that they’ve hidden a full flight simulator within Google Earth might make this worth revisiting. And of course there is infinite fun to be had from playing with photos etc on the globe, although my last attempts in that direction (preparing for 3 months in Buenos Aires by studying geo-tagged photos instead of Spanish) tailed off. Everyone was putting pics on maps, I got a bit bored, even though it’s still a worthwhile area with much still to be done.

Some ideas are not meant to be combined though: who really needs a collaborative realtime photo-navigator implemented with Google Earth flight simulator? :)

I’ve just posted 100 or so photos from the anti-Bush protest in Rome last night. Zac and I were on the way to a restaurant when we stumbled into the protest in Piazza Navona, just by the Senate where Bush apparently was in meetings. We wandered around the square taking photos of the protesters, then suddenly the mood changed from carnival to street fighting at the southern end of the square.

I tried geo-tagging some of the photos (see flickr map) but it is hard to be precise: I don’t know the square well, my memory isn’t perfect, and the tool doesn’t allow me to be clear about position, direction or subject of the image. But it helps. I didn’t see the fighting start, but I ran to the front to see what teargas tasted like (”sort of like lemon sherbet, with an initial zing then a slow, well-rounded plummy finish”; but doesn’t sit well with mild asthma), then hung around as the square was eventually cleared.

Main thing I take away from the experience: nothing says “body language” like street-fighting Italians…

köniuači
Originally uploaded by danbri.

In our daily lives we all respond urgently to dangers that are much less likely than climate change to affect the future of our children. … Feb. 2 will be remembered as the date when uncertainty was removed as to whether humans had anything to do with climate change on this planet. (Achim Steiner, executive director of the United Nations Environment Program via New York Times)

I learned a new word last month. Köniuači - from the Yamama word meaning:

Not reaching unto, or fairly unto as a rail a little too short, the end of which cannot be secured to the post in consequence. Unsupported, unsecure, not fastened securely, treacherous, incapable of supporting, as snow through which the foot breaks, or as the crust over mud. Not firm or solid, but suddenly giving way where one expected otherwise, fallacious, deceptive, ajar, loosened, incapable of being secured as the end of a rail to a post which is either too short or shattered to receive and hold a nail.

Good to have a word for that familiar concept. Does having a word for it make it easier to bear the idea in mind? Regardless, it is awful to be losing the language it came from, both culturally and academically. The above definition from Thomas Bridges’s Yamana-English Dictionary.

There’s only one native speaker left now. There were recently two - but they weren’t on speaking terms. Sometimes you just have to laugh. Thin ice…

When I wasn’t taking photos of melting glaciers, I spent a lot of my recent time in Patagonia reading this dictionary and other history of the area, and remembering the Workshop on Endangered Languages I helped organize in 1995 in Bristol. When you walk into an all-you-can-eat Chinese restaurant reading a dictionary, the staff are prone to glance nervously at each other. But I didn’t pace myself well, and their business model survived. Unlike my plans for selling homeopathically-dilute genuine preserved Glacier water to the ecologically minded, with the story that they’d hold it “in trust” in their fridges until the gaiasphere were healed and it was safe to release it back into the wild. Sadly I hit my baggage allowance, so the precious fluid stayed in Buenos Aires.

Anyway, the photo was from the Martial Glacier, Ushuaia, Argentina last month. Don’t ask me how much carbon dioxide went into the atmosphere to get me there and back again. This year I’m going to start taking my carbon footprint more seriously…

If you’ve not seen An Inconvenient Truth, I do recommend taking the time to watch it.

The Website opens with a quote that jumps out at me, since I write this from Leiden, Netherlands visiting the Joost offices, following a trip to Berlin, and preceding another to Rome:

It is difficult to get a man to understand something, when his salary depends on his not understanding it.

Instead of flying, should I be taking the train? Or a boat? Or getting better at remote meetings? Send money to plant-a-tree projects to clean my conscience? After a year and a half of working from the road or from home, it is great to actually be meeting up with people again, that much is clear. As I write, I wonder if there’s a “slow travel” movement akin to the “slow food” scene. I find a website of that name, though seems as-yet unconnected with issues of eco-disaster. Longer trips, perhaps by train, might make some sense. And more pleasant than stockpiling for the end-times.

A “Who? what? where? when?” of the Semantic Web is taking shape nicely.

Danny Ayers shows some work with FOAF and the hCard microformat, picking up a theme first explored by Dan Connolly back in 2000: inter-conversion between RDF and HTML person descriptions. Danny generates hCards from SPARQL queries of FOAF, an approach which would pair nicely with GRDDL for going in the other direction.

Meanwhile at W3C, the closing days of the SW Best Practices Group have recently produced a draft of an RDF/OWL Representation of Wordnet. Wordnet is a fantastic resource, containing descriptions of pretty much every word in the English language. Anyone who has spent time in committees, deciding which terms to include in some schema/vocabulary, must surely feel the appeal of a schema which simply contains all possible words. There are essentially two approaches to putting Wordnet into the Semantic Web. A lexically-oriented approach, such as the one published at W3C for Wordnet 2.0, presents a description of words. It mirrors the structure of wordnet itself (verbs, nouns, synsets etc.). Consequently it can be a complete and unjudgemental reflection into RDF of all the work done by the Wordnet team.

The alternate, and complementary, approach is to explore ways of projecting the contents of Wordnet into an ontology, so that category terms (from the noun hierarchy) in Wordnet become classes in RDF. I made a simplistic approach at this some time back (see overview). It has appeal (alonside the linguistic version) because it allows RDF to be used to describe instances of classes for each concept in wordnet, with other properties of those instances. See WhyWordnetIsCool in the FOAF wiki for an example of Wordnet’s coverage of everyday objects.

So, getting Wordnet moving into the SW is great step. It gives us URIs to identify a huge number of everyday concepts. It’s coverage isn’t complete, and it’s ontology is kinda quirky. Aldo Gangemi and others have worked on tidying up the hierarchy; I believe only for version 1.6 of Wordnet so far. I hope that work will eventually get published at W3C or elsewhere as stable URIs we can all use.

In addition to Wordnet there are various other efforts that give types that can be used for the “what” of “who/what/where/when”. I’ve been talking with Rob McCool about re-publishing a version of the old TAP knowledge base. The TAP project is now closed, with Rob working for Yahoo and Guha at Google. Stanford maintain the site but aren’t working on it. So I’ve been working on a quick cleanup (wellformed RDF/XML etc.) of TAP that could get it into more mainstream use. TAP, unlike Wordnet, has more modern everyday commercial concepts (have a look), as well as a lot of specific named instances of these classes.

Which brings me to (Semantic) Wikipedia; another approach to identifying things and their types on the Semantic Web. A while back we added isPrimaryTopicOf to FOAF, to make it easier to piggyback on Wikipedia for RDF-identifying things that have Wiki (and other) pages about them. The Semantic Mediawiki project goes much much further in this direction, providing a rich mapping (classes etc.) into RDF for much of Wikipedia’s more data-oriented content. Very exciting, especially if it gets into the main codebase.

So I think the combination of things like Wordnet, TAP, Wikipedia, and instance-identifying strategies such as “isPrimaryTopicOf”, will give us a solid base for identifying what the things are that we’re describing in the Semantic Web.

And regarding. “Where?” and “when?” … on the UI front, we saw a couple of announcements recently: OpenLayers v1.0, which provides Google-maps-like UI functionality, but opensource and standards friendly. And for ‘when’, a similar offering: the timeline widget. This should allow for fancy UIs to be wired in with RDF calendar or RDF-geo tagged data.

Talking of which… good news of the week: W3C has just announced a Geo incubator group (see detailed charter), whose mission includes updates for the basic Geo (ie. lat/long etc) vocabulary we created in the SW Interest Group.

Ok, I’ve gone on at enough length already, so I’ll talk about SKOS another time. In brief - it fits in here in a few places. When extended with more lexical stuff (for describing terms, eg. multi-lingual thesauri) it could be used as a base for representing the lexically-oriented version of Wordnet. And it also fits in nicely with Wikipedia, I believe.

Last thing, don’t get me wrong — I’m not claiming these vocabs and datasets and bits of UI are “the” way to do ‘who/what/where/when’ on the Semantic Web. They’re each one of several options. But it is great to have a whole pile of viable options at last :)

Handy article, “Towards Open Source Flash Development” by Carlos Rovira.

Background to looking at this is some great news: Mikel Maron is open-sourcing the WorldKit system, a lightweight Flash/SWF-based Web mapping application. So I’m interested to find some open source tools that would allow me to rebuild it from source.

I also wonder whether SVG hackers might be interested to port some of it to SVG/Javascript. WorldKit supports geo/rss location tagging, so I’m also curious about what it’d take to get full RDF support in there. Has anybody made an RDF parser for SWF/Flash yet?

This is just great: Digitally Distributed Environments: National Mapping Data with Google Earth. If only there were such data for Bristol. Maybe there is, somewhere…?

MozMapEditor screenshots look very promising. Layered map overlays, with polygon/polyline/point authoring, all built with XUL and SVG in Mozilla. I hope the overlays can be disentangled from the SVG and reused in GML, KML etc. There’s a mozdev site on the way…

The task of putting some of this information on the map is rather daunting, once you actually start wading through a pile of leaflets looking for locations, places, times, contacts details, Web addresses. But I think it can be decentralised, and the folk who make the leaflets, maps and guides for a city have a lot to gain from making their content more machine-accessible and freely share-able. Well, most of them do.