october 2003 archives

Thursday, October 30, 2003

Geo Tags

One of the precursors of GeoURL used to be Geo Tags. This initiative encourages website owners to add specific meta tags to the header of their web pages for position-based search engines and indexing. More importantly, the “geo.position” meta tag is even used by GeoURL to index websites. The Geo Tags initiative is based on the Internet Draft “Geographic registration of HTML documents”, submitted on 24 July 2003 by Andrew Daviel and Felix Kaegi:

This memo describes a method of registering HTML documents with a specific geographic location through means of embedded meta tags. The content of the meta tags gives the geographic position of the resource described by the HTML document in terms of Longitude, Latitude and optionally Elevation in a simple, machine-readable manner. This information may be used for automated resource discovery by means of an HTML indexing agent or search engine.

Recently, the Geo Tags domain has moved away from geographic searching: the Vancouver Webpages hosts the searchBC search engine, and provides free SIC classifieds to Vancouver area businesses. Links related to geographic searches return a “Document Not Found” status. However, the website still hosts the dictionary of HTML meta tags. The Vancouver Webpages also provide a description of the “ObjectType” meta tag. The ObjectType “RealWorld” can be used to specify the scale, orientation, origin, and geographic coordinate scheme for a given VRML world!

UPDATE: Geo Tags is up again and the Vancouver Webpages have moved onto their own domain. Curious affair!

Monday, October 27, 2003

Database: the new GIS, part 2

A few weeks ago, the introduction of Oracle 10g heralded a tighter integration of GIS and mainstream IT as Oracle further enhanced the spatial capabilities of its database product. As GIS does not only encompass data management and querying, but also visualisation, the announcement of the partnership between Oracle and Corel is a further step in this direction.

Now you can create, store and deliver XML content and present it as SVG graphics. For example, spatial objects encoded in GML are easily stored in Oracle. The result of various spatial queries can then be presented to the user as an interactive SVG map. The map elements can also be automatically linked to other database content, thus creating very powerful interfaces to complex data.

Wednesday, October 22, 2003

Next generation satellite navigation

While some 20 million people now regularly use GPS technology, the next generation, GPS III, shall be launched in 2010. This launch should be seen in the light of three important trends:

Signals will be available on more frequencies thus offering redundancy to overcome timing errors resulting from ionospheric refraction.
To fight radio-frequency interference (RFI) from nearby radio emitters, new GPS units match the phase of the received ranging code with a replica code stored locally. When the wave phases align exactly, the timing of the signals is used as a precise reference for the GPS unit to accurately locate itself.
Enhanced-reliability GPS technology, e.g. WAAS, will further reduce the guaranteed positioning accuracy.

However, since not only the US is advancing its GPS technology, questions are raised about possible use of competing GPS constellations by potential armed opponents of the US: the Europeans are negotiating with China to participate in the Galileo project.

Local search

Ever since Google and MapQuest teamed up in June this year, there have been some interesting location-based developments in the search engine arena:

Local listings accompany maps on the MapQuest and Weather.com websites.
The Google “Search By Location” service

However, this has not been the only initiative recently. This month, SearchEngineWatch.com run 3 articles on “local search”. The first article describes the disappointment of searching for local commerce using general purpose web search engines. To get a sense of location, the author recommends using directory search facilities on travel portals or online mapping sites: they typically present you the results on a map.

Also AltaVista provides mapping as part of local searching. A familiar top ten list of local results is produced and the listings are mapped across the map. One can interactively change the listings, based on the area displayed on the map: zooming out, the listings will cover a larger area. Clicking on the bottom of the map, the listings move southward. All this happens without needing to enter any new town names, helpful especially if you don't know the names of surrounding settlements.

The second article focuses on crawler-based methods to improve local searching, with strong emphasis on Google. Like AltaVista, the “Search By Location” service displays the search results on a map. The author notes that zooming out doesn't change the map, nor the top listings, although the number of results increases as it includes results from surrounding areas. I presume the “Search By Location” service sorts its results by distance from the centre of the map and determines the map size based on the bounding box of the results, so the behaviour described is not that surprising. Since the “Search By Location” service uses unstructured data, it doesn't produce a list of restaurants, each neatly identified by name and location. However, if you're searching the web for matches and then want to apply a geographic filter, the “Search By Location” service is one of the best tools for the trade!

There are quite some interesting observations in the articles already available. The third one is due on the 28th so keep an eye on SearchEngineWatch.com.

Tuesday, October 21, 2003

Killing two birds with one stone: inline frames

As the latest ASV does not support scripting when using the object element anymore, and the new version of IE will trigger a pop-up window everytime it comes across any of the object, embed, and applet elements, I have decided to start using the iframe element to embed SVG content in my website. There are various reasons for choosing the iframe element over the recommended embed element: more on this in the Experiments section. Also, I decided to use a plain image for the website logo instead of the SVG version.

Monday, October 20, 2003

Usage of geographic data in private sector frustrated

Last week, IT-Director.com carried an article outlining various reasons why the uptake of OS data outside UK government agencies is so limited. The article includes some rather bold (but very true!) statements. In summary, the writer argues that:

... the development and growth of the use of mapping data is being held back by poor commercial sense on the part of the agencies that own the data and poor implementation of standards from solutions providers.

As the OS ususally sell to other government agencies that are only interested in very restricted areas, the pricing structure does not fit private business usage, that typically requires map data for the whole of the UK. That's why the private sector turns to “on-demand” mapping services such as Streetmap and Multimap. Because of Crown Copyright restrictions, it's not allowed to save the data at all so that a new chargeable download is necessary every time. In short: the problem for the private sector is that it is being ripped off when it comes to buying map data. I couldn't have phrased it any more aptly myself.

Thursday, October 16, 2003

The end of the Web as we know it and its impact on web mapping

A few months ago, the web community was shaken up by Microsoft's announcement to discontinue support for IE. As this browser is the de facto standard, web designers and developers will have to make sure their efforts can still be admired in Microsoft's current browser version, although web standards and other web browsers will provide many more capabilities over the course of time before Microsoft will release its Longhorn OS. In itself there are not any real implications for web mapping specifically.

However, as a result of the outcome of the Eolas lawsuit against Microsoft, there will be a few changes to IE's handling of ActiveX controls and Java applets. Since any browser content that uses plugin technology (usually integrated using embed, object, and applet tags) will be affected, major companies such as Apple and Macromedia now provide information to assist web developers to smoothly overcome the disruptive plugin behaviour proposed by Microsoft. As a lot of web mapping applications are being created with Flash technology, this change will have a significant impact on web mapping. Also, most Web GIS software packages use plugin technology to interact with the web mapping applications. These applications shall have to be recoded to serve so-called “active content” to their audience in a smooth fashion. Last, but not least: to incorporate SVG graphics in your website, you will need to recode your website to create the embed tags at run-time. It seems no one will escape the negative effects of this court ruling!

So are there any positive sides to this then? Some people are convinced that Microsoft won't need any plugin technology as IE already supports VML and JScript natively, providing an embedded alternative for Flash and Actionscript. Others see this change to IE as a time for embedded SVG to shine! Someone else pointed out that Macromedia may even open-source its Flash player: giving Microsoft the opportunity to natively support Flash in the future. But then again, a few weeks ago Macromedia announced their Central product at Flashtival in Amsterdam. Macromedia Central creates one coherent, unplugged experience integrating web content and other information outside web browsers. So maybe the future for web mapping is Flash? Never thought I would say that a year ago!

New ASV plugin: embed only

Having tinkered with my website design for a while, it's about time I look into some content-related issues. Since I updated my SVG Viewer a few weeks ago, the SVG graphics on my website are not responding to the mouse movements anymore! I only just found out why:

Adobe SVG Viewer 3.01 always disables scripting when it determines that the SVG file is embedded using the object tag. When authoring in SVG, Adobe recommends that you not use the object tag and instead use the embed tag when embedding SVG in HTML pages.

So I'd better start recoding some of the pages here and also update my tutorial on serving SVG. There's actually quite a lot to be said at the moment about plugin technology ever since the outcome of the recent case of Eolas v. Microsoft in regards to US Patent 5,838,906. As a lot of experiments at webmapper.net use various examples of plugin technology, be sure to read here more on this matter soon!

Tuesday, October 14, 2003

A statistical anomaly

When you come across some weird variations in labour statistics of Utrecht in the next few months, that would probably be me... That's a bit of an exaggeration, but still: the surveyor from CBS that came round last night had quite some difficulty entering my responses.

As there is no national census anymore in the Netherlands, 10,000 surveyors go and interview randomly selected people every evening! When would “Jedi” become a religion in this country? Anyway, it was very interesting to contribute to these statistics for once rather than just mass-consuming the data for the National Atlas of Public Health.

Location dead?

It's more alive than ever, I would say! Starhill gives an interesting account of the geography-related discussions at FOO Camp 2003. Surprisingly, there was some Dutch input as well: Dirk-Willem van Gulik, president of ASF, presented a WMS implementation that serves satellite imagery.

More and more, I am thinking to organise some off-line event to bring people together that work with OGC technology in the Netherlands. That would certainly make a change from the boring stuff that's usually discussed when it comes to mapping in this little country...

Monday, October 06, 2003

OS: Soon in cinemas near you

Ordnance Survey appointed a new Non-Executive Director last week. Interestingly, Mike Sommers has been Managing Director of MGM Cinemas (UK) Ltd. Do you see a trend coming on? Just recently, its CTO put recent developments in the music industry as an example for how the GI industry should adapt to the requirements of its costumers. Maps as entertainment! As the OS are really into making money these days (their “gov.uk” domain even redirects to “co.uk”), what better industry to go for than entertainment?

Friday, October 03, 2003

Licence to map

After Wednesday's article in the Independent pointing out that the Queen is in effect fighting herself when it comes to Crown Copyright and geographic information, here's another example of the miserable state of affairs of mapping in Britain!

Multimap has partnered with eMapSite, the one-stop shop for digital map images, to provide you with a quick and easy way to purchase maps like those shown on the Multimap site for your own business or personal use. This new service allows you to buy digital mapping for use in presentations and emails, or for printing, complete with a full licence. Since all materials on Multimap's public site are copyright-protected, this service is the best way to ensure that you're using our maps correctly and legitimately.

On eMapSite, a licence for one personal use costs you £49.99 for a 750 by 750 pixel map image or £0.10 per copy for a print licence. Next time you invite your friends to a BBQ, be prepared to dish up 50 quid before emailing them a map of your own house for them not to get lost! Yeah, right: as if... And if you look a bit further you'll find this on the OS website:

You are authorised to download a maximum of 10 images from the Get-a-map service for use on your web pages, providing the following credit appears below all images: [blah, blah, blah]

You are authorised to make a maximum of 10 copies of each mapping image as displayed on your browser for personal, non-commercial use only.

As long as you do not invite more than 10 people to your party, use the licence fee to pay towards your alcohol bill! Furthermore, these terms of use don't feature anywhere on eMapSite, thus tricking law-abiding citizens into buying an OS licence.

Thursday, October 02, 2003

21st Century Willy Wonka

Is it because next year will see the remake of “Willy Wonka and the Chocolate Factory” that prize draws are adopting innovative ways to get attention? Even rap star Eminem is hiding the golden tickets in CDs! Finding one of the three golden tickets among the first 500,000 copies lands you an all expenses paid trip to Eminem's studio in Detroit to watch him work on his next album.

Coca-cola also jumps on the bandwagon: it plans to use satellites to find US buyers who happen to purchase special cans of Coke products. The winners in a giveaway will receive a Hummer H2 sport-utility vehicles. The giant vehicles will be presented in person, using satellites to locate the recipient!. Budweiser ran a similar competition last year when it put GPS transmitters in 25 special cans across the UK.

Wednesday, October 01, 2003

Eleven reasons

A few weeks ago, Jaron Lanier gave a talk in the Bay Area titled “Why VR has not (yet) become a widespread technology”. Jason had put together a list of the top eleven reasons for people to come to the talk prepared. Mike Liebhold soon followed with a similar list to re-think the recent hype around location-aware devices:

Expensive gadgets (You bet!)
Small screens (Ever tried to view an OS map on a phone?)
Small memory
Short battery life
Useless device form factors (Hmm... could CSS tackle this?)
Poor application user interfaces
No standard web geocode format (Had a glimpse at the OGC spec recently: ough!)
No geographic search engines (Google's making interesting progress here!)
Few location sensing networks
Clunky GIS data interoperability
Add your own...

Well, that certainly brought us back to Earth! Devices, applications, and data are all in their infancy still. That's for sure. But we can only experiment with what we have got right now without pretending it to resemble anything that will make location-aware devices go mainstream. Am I contradicting myself with some of the things I wrote before? Well, what I was saying before is, that the ability of these devices to track their location make them stand apart from our desktop PCs! I am still convinced of this. All other applications of mobile devices try to emulate what we can do on our PC, but once we add tracking capabilities to the mix, mobile devices become a league of their own!