### Archive

Archive for the ‘rambling’ Category

## an exercise with math equations…

February 21, 2007 1 comment

I’ve just found out that I can write complex math equations using Latex syntax on WP. Here’s my first try:
$(K_{i}\varphi \wedge K_{i}(\varphi \Longrightarrow \psi)) \Longrightarrow K_{i}\psi$
Wow! Great! Learned this from this blog post.

Categories: rambling

## Using OwlDlTrHReasoner

OwlDlTrHReasoner is a new OWL DL reasoning module added to Bossam, which shows much better performance than Bossam’s default OWL DL reasoning module. You can create an instance of OwlDlTrHReasoner by calling bossam.app.IReasoner.createOwlDlTrHReasoner().

In Bossam shell, instead of owl, use owltr as follows:

load owltr from http://www.w3.org/TR/2004/REC-owl-guide-20040210/wine;

Yeap. That’s it. OwlDlTrHReasoner completes a forward-chaining reasoning session over the W3C wine ontology in less than 3 seconds, on my 1.8Ghz Core Duo notebook with 128MB of Java heap memory. Not bad, right?

Doesn’t that reasoner lose too many derivations? Well, actually, I have to see from now on… 🙂 I’d be greatly appreciated for any feedback and problem reports on this new reasoner. 🙂

Categories: bossam, manual, rambling

## Speeding up Bossam…

I’m working on a new implementation of Bossam’s OWL reasoning module. There’re roughly two approaches for rule-based OWL reasoning. One is translation-based approach and the other is meta-reasoning approach. Bossam’s OWL reasoning module originally is implemented in meta-reasoning approach, but now I’m working on a translation-based OWL reasonnig implementation for Bossam. I’ve just finished the first draft of the code and it looks quite promising in the sense of performance!

• A full forward-chained reasoning session on the W3C wine ontology completed in 1.5 seconds!
• A full forward-chained reasoning session on the LUBM benchmark with 100,000 triples completed in 97 seconds! All the 13 sample queries are processed in less than 1 second!

Stay tuned! One major performance-tuned Bossam is coming!

Categories: rambling