Geospatial Semantic Web Blog

SIOC (Semantically Interlinked Online Communities) is an ontology for expressing information about online community sites. This includes weblogs, bulletin boards, forums, etc.

Uldis Bojars has written a WordPress plugin for easy publishing SIOC information. Instructions to install the plugin is available here. The SIOC description of this blog is here. The SIOC description of John Breslin’s blog is here.
What can I do with SIOC? By itself, SIOC does nothing more than publishing some meta-information about an online community site in RDF. However, if majority of the websites publish similar meta-information in SIOC, one day we can build more expressive search interface to answer questions like

“Find all community site post:
(1) Containing the words “Broadband Galway Linux”,
(2) Created less than one year ago, and
(3) That were read at least 20 times.”

The Web has tons of information. The Web also has tons of geospatial information that computer programs don’t really know how to acquire and make use of.

The Web has helped people to be more productive. Geospatial applications such as Google Maps, Google Earth and other “mash-up” applications not only increased people’s productivity but also made their computing experience more enjoyable.

The present Web applications mainly focused on the presentation of information and the enhanced computer-user interactions. While it’s important to continue our innovations in these areas, but also it’s important to tackle new problems that can’t be solved by simply building better UI or more dynamic web pages, e.g., geosptaial semantics.

There are different types of geospatial information on the Web: maps of the Earth surface, digital photos of geographical locations, text documents that describe different world places, events, and people, etc. While information is expressed in ways that are suitable for the humans to understand, but it’s not so for the computer programs. It’s often difficult to develop software programs that can effectively search, discover and reason about the Web’s geospatial information. I called this type of information the hidden geospatial knowledge.

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In mid-16th century, Spanish cosmographer Alonso de Santa Cruz created one of the only two known maps that give a fairly accurate picture of the city of Mexico. Because this map is so precious, access to this map has been restricted to only few groups of people.

The Digital Facsimile project is about to change this. This project was a collaboration between the Media Lab of the University of Art and Design and the Institute of Photogrammetry and Remote Sensing of the Helsinki University of Technology.

On the project’s website, users can find a digital representation of the map. Users can navigate to different parts of the map like the way they do on Google Maps. In addition, authorized users can also annotate the map like the way they do on Flickr.

The site talks a bit about the history of this map. The story was spotted on Planet RDF, posted by Ora Lassila.

After reading this blog entry, a reader asks the following:

The definition [of geospatial semantics] is convincing. However, could you tell the difference between the “Geospatial semantics” and Egenhofer and Mark (1995)s’ “Naive Geography” which defines as : “The body of knowledge that people have about the surrounding geographic world.”

In this post, I will try to answer Andrea’s question.

I believe there are similarities and differences between the studies of Naive Geography and Geospatial Semantics.

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