Just visited the “Centre de recherche en géomatique” in Quebec City

Yesterday, I gave a talk at the Centre de recherche en géomatique. I was invited by Yvan Bédard to visit his lab, meet his students and discuss his projects. To give you an idea, Yvan published 400 papers, he has 4 full-time contract employees, two post-doctoral fellows and something like 15 graduate students in his lab. He has for $750k in software alone in his laboratory. He must be one of the top researcher in “spatial OLAP” (which he calls SOLAP) in the world. He works at the geomatics department in Laval University. It is one of 3 geomatics departments in Canada. (While I don’t have a definition of geomatics… it is all about mapping and measuring distances, and so on.)

Some of his projects include decision-support tools for trainers who work with top athletes: through fine-resolution GPS, you can track the an athlete, collect all this data, pour it into data cubes and make various comparison, see where, on the track, the athlete is improving, where he is not improving, and so on. He also built a tool to mine road conditions and help set repair priorities.

We discussed various research issues such as the fact that rebuilding the cubes is expensive in a spatial-temporal context, and how view maintenance appears to be lacking from current commercial tools like SQL Server (I’ll need to investigate this particular issue). He has committed to achieving real-time data cubes in 5 years (which implies continuous updates) for his current portfolio of applications.

The use some already available classical multidimensional indexing techniques such as R-trees and R+-trees. However, they are fairly dependent on currently available commercial (and open source) tools as they focus mostly on the application layer and specifically on the geometry and topology of the data.

I’m very impressed.

Myself, I presented some of the work I do with Owen Kaser as part of the Lemur project, including Attribute-Value Reordering and Relative Prefix Sum Methods. I got people laughing, so either they thought I was ridiculous or else, they enjoyed my style. There were many questions and people seemed to be interested, so maybe they thought it wasn’t silly work after all.