Different Kinds of Geospatial Data
Geospatial Semantic Web
The most value asset in a GIS system is data. Without data, a GIS system is like a computer system with the best peripherals but only with an empty hard drive — it’s useless. If data is so important, it is necessary for us to understand the role of data in the future GIS systems — i.e., the Geospatial Semantic Web.

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Posted in Semantic Geospatial Web, Geodata, Mapping, Geocoding February 7th, 2006 by harrychen | Tags: geospatial, GIS, geospatial semantic web, mashup, knowledge representation | No comments | Post to del.icio.us | Digg this story | I Reddit

MOD: Mashups of the Day
daddytypes.com: a Google Maps mashup that shows all known New York City men’s rooms with baby diaper-changing tables. This mashup was featured in a recent New York Times article.
Kayak Buzz: a Google Maps and Kayak mashup that tells you where you can go for under a certain amount of money? It displays airfares under a user defined amount of money on a Google Map.
Posted in Geospatial Applications, Semantic Geospatial Web, Mapping, Mashups of the Day February 6th, 2006 by harrychen | Tags: maps, baby, NYC, travel, kayak, mashup, technology, gis, geospatial | No comments | Post to del.icio.us | Digg this story | I Reddit

Virtual NYC Tour with Google Maps and Wiki
Mash-up is a buzz word these days. Mash-up applications are applications that exploit two or more distinctive technologies provided by some existing applications and combined them to create new capabilities.

Virtual NYC Tour is an interesting mash-up application that exploit Google Maps and Wiki.

The site, www.virtualnyctour.com, lets users choose from 17 different trails for a “walking tour” of locations such as Soho, Ground Zero and Central Park. A map pinpoints the user’s location while photos show what can be seen along that route (cars, trash bags on the sidewalk, people talking on cell phones, and, oh yeah, amazing architecture). Alongside that are historical and other summaries from Wikipedia.

Posted in Google Maps, Geospatial Applications, Image Annotation, Yahoo! Maps, Semantic Geospatial Web, Geodata, Mapping, Geocoding January 19th, 2006 by harrychen | Tags: google maps, wiki, nyc, tour, mash-up, geospatial, gis | No comments | Post to del.icio.us | Digg this story | I Reddit

An Optimal Way to Geocode Locations Using Microformats
In the past, I talked about the use of microformats to geocode locations on the Web. Microformats is a new approach that attempts to introduce meaningful markups in the existing HTML pages. In particular, it exploits the use of HTML attribute values.

Norman Walsh has a post that discusses different ways to encode the latitude and longitude information of the Eiffel Tower using microformat.

There is also an interesting comment from Elliotte Rusty Harold that shows how the same information can be encoded in a more optimal representation.

Just be warned. The described approach only works if the end user application (e.g., a browser) knows how to ignore the non-standard HTML tags. Otherwise, it may create problems during the page rendering process.

Posted in Ontology, Semantic Geospatial Web, Geodata, Metadata, Geocoding January 17th, 2006 by harrychen | Tags: geocode, geospatial semantic web, microformat, gis, semantic web, semanticweb, xml, html | No comments | Post to del.icio.us | Digg this story | I Reddit

Is Geospatial Ontology Just a Bunch of Tags?
People often ask the question:

Is geospatial ontology just a bunch of tags (e.g., XML tags, technorati tags or flickr tags)?
Why is it so important to differentiate tags from ontologies?
Before I try to answer these questions, let me say few words about the term “ontology” with respect to computing systems.

What’s Ontology?
The concept of ontology originates from the studies of philosophy. Today in computer science, especially in the field of Artificial Intelligence, ontology is a set of vocabularies and relations that people or computing machines must agree upon in order to communicate. Without sharing a common ontology, they won’t be able to share information effectively.

Why I think Tags are not Ontology
Let’s take the technorati tag “cell” as an example. The term cell in our pop culture could mean cellphone, the smallest basic unit of an animal of a plant, or a small residential accommodation in a prison. Let’s say you tagged one of your blog post with the tag “cell”. This blog post was later discovered by a technorati search bot. Now the question is how much information can the search bot learn from the tag “cell”?

No much. All it knows is that your post is tagged with an English word that spells ‘c’, ‘e’, ‘l’, ‘l’. It probably doesn’t even know your post is about cellphones, human cells or prison cells.

A natural question to ask is that can we do better? For example, can we help the search bot to know more about the content of our blog? In other words, can we help computing systems to understand the semantics of information?

I don’t know for sure, but I do believe it’s possible. In fact, many ongoing Semantic Web efforts in OGC and W3C are working to solve this kind of problems.

Coming Back to Geospatial Ontology
Once we understand tags are not ontology, we can immediately conclude that geospatial ontology is not just a bunch of tags. What makes geospatial ontology so interesting is that much of the information in our everyday life involves some kind geospatial ontology. If we are on the path to develop computing systems that could understand the semantics of our blog posts, for example, we must pay extra attention to geospatial ontology.

In the near future, I will discuss geospatial ontology development and its usage in real world applications.

Posted in Ontology, Semantic Geospatial Web, Geodata, Metadata January 17th, 2006 by harrychen | Tags: ontology, tags, technorati, ogc, w3c, geospatial, gis, geospatial web, semantic web, geospatial semantic web, flickr | No comments | Post to del.icio.us | Digg this story | I Reddit

New Geospatial Semantic Web Podcast Page
Today I added a new page that collects podcast shows that discuss geospatial technology and the Semantic Web. Unfortunately, we haven’t yet seen shows that specifically focus on the cross-fertilazation of the two technologies. I hope this is going to change in the near future.

http://www.geospatialsemanticweb.com/podcasts/?

Posted in General, Semantic Geospatial Web January 10th, 2006 by harrychen | Tags: podcast, geospatial semantic web, gis, geospatial, technology | 1 comment | Post to del.icio.us | Digg this story | I Reddit

Podcasts
For those who love Podcast, here is a collection of Podcast shows that discuss geospatial technology and the Semantic Web. If you have a show that you want to add, email me.


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Interview with Peter Morville (author of Ambient Findability), VerySpatial Podcast, January 15, 2006.

Summary: VerySpatail interviews that Peter Morville on the subject Ambient Findability. Ambient Findability is a notion that describes things in the physical world can be easily found, tracked, searched, and geo-located in an anywhere any time fashion. Peter thinks Ambient Findability is the cross-breed of ubiquitous computing and the Web.


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The Quest for Reliable Directions, NRP, January 10, 2006.

Summary: Experts talked about map data usage in popular mapping service web sites such as Yahoo! Maps, Google Maps and MapQuest.


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The New Sense of the Web, OnPoint with Tom Ashbrook, January 03, 2006.

Summary: The digital realm is exploding into the physical world. They call it the “geo-spatial web.” Already it means online maps loaded with information about the physical world, and someday soon, that physical world itself will be tagged and teeming with data for the asking: What is that building? Where is my dog? Who is that man? Hear about the ambitions and implications of the “geospatial web.


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Turn left at the Internet, MarketPlace, November 22, 2005.

Summary: Online mapping programs are among the most popular Internet tools. Trade in geographic data generates hundreds of millions each year. Rachel Dornhelm talked to the folks who give those online sites their sense of direction.

Posted in General January 10th, 2006 by harrychen | Tags: podcast, geospatial, gis | 1 comment | Post to del.icio.us | Digg this story | I Reddit

ESRI Federal User Conference
The ESRI Federal User Conference (FedUC) is January 31?February 2, 2006, at the Washington Convention Center in Washington, D.C. The conference supports those who deploy ESRI software for geoprocessing and analysis, integrated work flows, and intelligent collaboration across government. (source blog)

Going through the program schedule (pdf), I see a lot of interesting application domain that could exploit Semantic Web technology. I think the use of ontologies and RDF can be useful in the following domains:

Defense Installation Spatial Data Infrastructure: the Year of Alignment (page 3)
WMD Response in a Joint Civil and Military Environment (page 6)
GIS for Homeland Security and Emergency Management (page 8 )
Preserving GeoSpatial Data (page 12)
I’m quite disappointed to see the word “semantic” is not mentioned anywhere in the entire 27 pages document. The word “intergration” is mentioned is 15 times. Do people really believe that knowledge integration problems can be solved without some kind of understanding of the semantics?

Posted in General, GIS in Government, Geospatial Applications January 9th, 2006 by harrychen | Tags: esri, conference, geospatial, gis | No comments | Post to del.icio.us | Digg this story | I Reddit