february 2003 archives

Friday, February 28, 2003

Trimble and Rosum Corp. have signed an agreement to combine GPS technology and “Rosum Positioning Technology” (RPT). The combination extends the reach of GPS into difficult environments, such as “urban canyons”, parking garages, and even indoors.

RPT uses the megawatt-level broadcast television signals to provide accurate positioning in urban areas:

TV signals are already concentrated in urban areas.
Many TV signals from different directions enable accurate triangulation.
Synchronisation signals are already embedded in the UHF waves.
It doesn't suffer from ionospheric effects or transmitter Doppler as is the case for GPS.
The UHF waves can penetrate deep into buildings and structures.

Sounds like an interesting match. Still, its accuracy depends on the “almighty” US government. What happens if all of a sudden they decide to switch back to Selective Availability (SA) as discussed last year? You never know what excuse they come up with because of the “Current Situation”...

Monday, February 24, 2003

The trend of mapping blogs has evolved since last month: the latest project is Blogmapper. The map acts as navigation interface , allowing users to move around blog entries via locations on the map. Blogmapper is based on open RSS technology and a simple extension of RSS called RDFMap for adding location and basic mapping information to RSS. I only found out about Blogmapper after one of its developers linked to webmapper.net from his blog...

When you're blogging from home, this is of course not very exciting, as most entries will be positioned on the same location: or you “geo-tag” your posts based on the location that is described in the post, e.g. “Saturday night I went Fabric on Charterhouse Street”. More exciting though, is to map out your blog posts when you're on the move. Been thinking of doing just that with the blog posts I wrote when I was in Mexico where you could find an Internet cafe around every corner. In other places, this is a bit more difficult, so then you have to resort to “moblogging” (= mobile blogging).

Wired ran an article on this the other day. It describes various tools for people to update their blogs wirelessly, using a mobile device to send e-mails or text messages to a service that subsequently uploads it onto the blogging website. More sophisticated services even interact directly with the blogging website, and allow you to upload the photos you just took with your mobile phone! So the next step is for these devices to obtain their location automatically and attach it to the blog post! Wahey...

Was only a matter of time before Wireless DevNet picked up on this...

Saturday, February 22, 2003

If you want to re-live driving across London before the congestion charge, there's a virtual escape: The Getaway. Released in December last year, this PlayStation game has recreated central London as the virtual backdrop of the game: gamers undertake a variety of missions criss-crossing London on foot or by car. It has taken the real-world geography into the game.

Botfighters, discussed here before, has taken the opposite route: it has taken the game into the real-world geography. In one of the sessions at GDC Mobile 2003, Sven Hålling, CEO of It's Alive, will discuss the early deployments of Botfighters. The game is based on the concept of “pervasive gaming” the game surrounds the player, 24 hours a day, everywhere. Walking down the street, the player walks through an adventure world draped on top of the real world. Each person and every location may have a significance in the game: friend or foe, virtual lover, or evil warlock, just a tube station or headquarters for secret agents? Knowing where you are is not only useful, but can be fun too: location has firmly established itself in the gaming industry.

Tuesday, February 18, 2003

All right, it may be half-term hols at the mo, but the Congestion Charge really seems to have an effect (for as long as that lasts, of course). It was quite surreal last night to see traffic flowing up and down Holborn at rush hour!

So what are the geographic sides to this scheme. First of all, there's of course the map (PDF) of the congestion charging zone. Stanford's also stock a map of London by the Geographers' A-Z showing the Zone's boundary, although it doesn't feature on their own website! Neither Streetmap.co.uk, nor Multimap.com have updated their websites yet to show maps highlighting the congestion charging zone.

Since residents living within the congestion charging zone are eligible for a 90 percent discount, the London Congestion Charging Homepage features a store locator so residents can find out which addresses are in the zone. Users provide a postcode and a house number. Having disabled pop-ups in my browser, the store locator didn't seem to work for a moment: submitting the form a new window is opened with a list of full addresses to choose from. Once the address is selected, the store locator then simply informs you whether the address is inside or outside the Congestion Charging Zone. Unfortunately, no further information is provided (e.g. nearest zone entry/exit location, nearest location where you can pay the charge). A missed opportunity.

To enter the zone, car owners can pay the congestion charge at PayPoint outlets and at BT Internet kiosks. The PayPoint store locator is a missed opportunity... Users can search per county or by entering only the first part of their postcode (e.g. “W2”). Entering the full postcode (e.g. “W2 3HH”) returns an error! A simple regex could have prevented a lot of frustration here. In summary, the store locator uses an attribute search, instead of a spatial search. Still, something is better than nothing as there is no store locator provided to locate your nearest BT Internet kiosk.

To enforce the congestion charge, there are 230 camera positions monitoring every single lane of traffic at both exit and entry points to the charging zone. The cameras are the eyes (no, they don't have ears!) of the so-called Automatic Number Plate Recognition (ANPR) computer system. There's no official map indicating the locations of the cameras for fear of sabotage, but this seems the perfect opportunity for community mapping!

Headmap released its latest and greatest late last week: Blogosphere 2 (not sure what “2” is about, though). To annotate a location in space, users click on a globe to obtain coordinates, or enter lon/lats derived from other websites or from GPS-enabled devices. Then, users label their “post” with a title and a URL. Submitting the form, the location is then added to an XML-encoded list. Vice versa, the globe reads the XML file and displays the list of locations marked as points on the globe. Each of the points is a hyperlink that opens a page in your browser window.

“Tagging space” seems to be the latest phenomenon. As previously highlighted, UpMyStreet Conversations enables users to discuss local matters with people in their neighbourhood (as in “this is a local shop for local people” ;-)...). When Multimap.com started out in 1997, its popularity grew rapidly due to the “Free Links and Maps” service that feeds into the Local Info service. Using the automatic link generator, users create a URL that they copy and paste into their HTML. To be listed in Local Info, users select a category that best describes their website and the Multimap.com webcrawler automatically finds the reciprocal link within 1-2 days and adds the listing to their database. These reciprocal links make up the majority of the information you can access through the Local Info service. More and more it is exploited by including paying customers such as estate agents to promote their property.

Blogosphere 2 addresses the problem of filtering collections of geographical datasets. People publish the “location-linked” data on their own websites rather than in a central database. Therefore, they can choose to use data from a trusted source. Instead of searching a central database (as in the Multimap.com scenario), users can obtain “personal” answers to their general questions like “Does John know of a good surfing spot near Perth?” by checking John's globe. As the data is stored as an XML-encoded list, people can share and combine location-linked information with others to build up a collection of shared knowledge. Thumbs up for Headmap!

Monday, February 17, 2003

Some celebrities sometimes seem to have disappeared from the face of the earth... Multimap.com helps you locate them ;-)!

Friday, February 14, 2003

The Streetmap.pm module I mentioned the other day has received a lot of attention since. First, of course amongst the London-based PERL Mongers, and, guess what: it even made it to Slashdot. Apparently, both sides have come to some understanding after two weeks of slinging mud at each other, so we might see the module back on CPAN soon again. In the meantime, there is an alternative module: WWW::YahooMaps. In one of the posts, Multimap.com was dismissed as its maps are annoyingly not square!

Wednesday, February 12, 2003

Maybe it's a bit of a late epitaph. Yes, I should have noticed this earlier, really. The Xerox PARC Map Viewer has been deactivated, according to the homepage that was last updated Tuesday, 15-Oct-2002 12:54:59 PDT. The Xerox PARC Map Viewer was created in June 1993 by Steve Putz at Xerox Corporation's Palo Alto Research Center as the world's first online database-driven mapping application!

A few weeks ago, MySQL, the Open Source RDBMS announced that version 4.1. will support a subset of GIS data types as proposed by the OpenGIS consortium, which can be used for efficient spatial data querying. More about the technicalities behind this (such as the R-tree search algorithm) can be found at Jeremy Zawodny's blog.

Tuesday, February 11, 2003

Typing “www.shellgeostar.com” in the address bar of my browser this morning, I was immediately redirected to the ViaMichelin website! In other words, it seems that of the two main routeplanning websites in Europe, there's only one left! Quite a hit for Maporama too, I'd say: they used to run the Shell GeoStar website. So who's doing Shell's European dealer locators now? From the look of it, it's that other online mapping provider in Europe!

Saturday, February 08, 2003

A while ago I came across PLSJ in Blogger's “Blogs of Note”, a blog maintained by a PhD candidate in the Sociology of Virtual Spaces program at Carleton University, Canada. I don't usually link to other people's blogs, but it's an interesting read, especially the stuff about ubiquitious computing, as it has some intersections with LBS. Funnily enough, yours truly was linked to a while ago by Headmap. This blog discusses some great topics related to location aware devices and psychogeography.

Headmap may well have been where I found out about GeoNotes. This LBS service detects your current geographical position in the network and allows you to virtually write “tags” and graffiti at that place. Vice versa, this allows you to read, browse and search the GeoNotes friends left for you at locations in space! Quite cool, huh?

A similar, albeit web-based endeavour emphasising the social aspects of LBS is “UpMyStreet Conversations”. This new feature on the website that brings together information about property, schools, local business, puts users in touch with people who live in the same area. As every conversation is centered on a postcode, people can browse through “conversation space” by simply typing in postcodes. So it's a great forum to discuss local topics such as local transport, the best restaurants and bars in the area, or for organising and announcing events in the community.

Interestingly, I found a post on the ”Ask Edward Tufte” website from one of the developers of the UpMyStreet Conversations. For the first time (to our knowledge), it is possible to plot the course of an online discussion as a directed graph on a physical map. Possibly even as an animation. different variables (length of message, username, time to reply, number of replies) could be represented on such an map. It would be very interesting to see how useful these maps are to the people in the discussions...