Geospatial Semantic Web Blog

The ability to represent time and temporal relations is an important aspect of the Semantic Web. W3C recently published a new working draft on Time Ontology in OWL. This work is an updated version of the OWL-Time ontology developed by Jerry Hobbs and Feng Pan.

Before the standardization of the OWL language, Jerry and Feng also worked on a version of the ontology in DAML. Their previous works on time ontologies can be found at Feng’s OWL-Time website.

In the RDF and OWL world, there are at least two different ways to represent time. One way is to use XSD datatypes (e.g., xsd:datetime), and the other is to use OWL-Time. Sometimes people ask me which approach is better for representing time in their applications.

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Guardian Solutions, a Florida-based video surveillance solution provider, has developed a new software product that uses Google Earth to display 3D models of video surveillances intelligence.

This new product, GView (TM), is aimed to provide the mass market an effective tool to gain the benefits of situation awareness — e.g.,stopping vandalism and defeating malicious activities such as sabotage and terrorism.

While I was digging for GView screenshots, I found few interesting clips of the company’s video surveillance technology.

• Tracking a boat in the sea
• Tracking traffic movements in the dark
• Tracking intruder
  
• Directional movements detection

Geonames.org is a popular GIS web service built on the simple REST framework. Not only it’s excellent platform for building innovative web applications that require access to GIS data and geocode services, but also it’s a poor man’s solution to ArcGIS Server (sort of).

A Java API for accessing Geonames web service has been released. Check out the project page at its SF.net page. Look at this page for a quick code example. If you need more information, see its Javadoc page.

To geotag blogs is to annotate weblog posts with geographical information. There are at least few reasons why this is a good idea.

Geotagged blogs will enable web search engines to effectively index blogs based on geographical information. This information will help to build more powerful search engines that support spatial queries (e.g., find all blogs on the topic “war” and written by people who are located in “Iraq”). Moreover, geographical information of blog posts will also help us to understand the trends and the ecology of the blogosphere (e.g., what’s the most discussed topic in a particular geographical region, and how opinions differ between people who live in different counties?) At present, these studies are done by collecting IP locations of the bloggers and the written languages of the posts (I think).

There are few different languages and tools for publishing geographical information about blogs, for example, GeoRSS, Microformats, W3C Geo, FOAF, WordPress Geo Plugin (see also [1]).

A question I ask myself today is that “if we already have the languages and tools for geotagging blogs, why geotagged blogs are rare in the blogosphere?”

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Home Depot Canada provides home-delivery service to its customers. In the past, service charges are quoted to customers based on a flat rate system — one rate for all deliveries within 15 kilometers of the store, another for 15 to 30 kilometers and another for 30 to 45 kilometers. With the help of GIS, using map data provided by Canada Post, Home Depot Canada is able to provide more accurate quotes based on the postal codes of the customers.

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RDF Semantic Web research isn’t working, Zack Rosen complaints. This kind of criticisms we hear often. As a Semantic Web researcher, I’m not too upset about it, but rather I think it’s a great opportunity to reflect — where are we now after eight years of Semantic Web research, and where are we heading towards to in the next eight years?

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SIOC is an ontology for describing information from online community sites. You can read about SIOC and its applications in my past posts.

SIOC Exporter is an easy-to-install WordPress plugin for automatically generating SIOC description. For blogs to publish SIOC is like publishing RSS feeds, except that SIOC feeds are expressed in RDF and includes a bit more meta information about the blog sites.

In addition to the use of basic SIOC vocabulary, SIOC Exporter version 1.19 also adopts additional vocabularies from FOAF and Dublin Core. This can help existing web applications that already exploit FOAF and Dublin Core descriptions to understand information published by SIOC-enabled blogsites.

You can browse this site’s SIOC description using the SIOC browser.

SIOC is heavily used by talkdigger.com, which transforms non-RDF blog posts and online conversations into RDF. Frederick Giasson explains his talkdigger vision.