Re: [UCR] Design constraints: early example goal/csf hierarchy --> PR / PRR

On Apr 19, 2006, at 6:35 PM, Vincent, Paul D wrote:
[snip]
> The [OMG] PRR team are addressing this by looking at 2 common types of 
> production rule semantics (Rete rule engine and procedural / 
> sequential execution of rules). There are enough similarities between 
> the commonly used engines (Fair Isaac Blaze, ILOG JRules, JESS/Oracle, 
> etc) that a broad area of commonality is possible. However, EVERY 
> vendor of course has their own “quirks” which means PRR is a SUBSET of 
> possible rule languages (albeit, we feel, a common subset). Which 
> means PRR is a bit like SQL I guess – a common core with vendor 
> extensions, and caveat emptor for developers (ie use the common subset 
> for portability, or vendor extensions for, er, “non-portability”).
>  
> I’d assume the same (common subset implementation) would be true for 
> logic representations / KR / OWL rules, for RIF v1-n at least?
[snip]

I'd like to address the OWL case. By and large there is some attempt at 
convergence. The current most commonly omitted feature is nominals (and 
perhaps some datatype stuff), and the current most common extension is 
qualified number restrictions (and perhaps query, though query is 
hoping to converge on SPARQL).

(There are also experimental extensions, for example, Pellet implements 
E-Connections, and KAON2 implements DL Safe rules, etc.)

But the *community* by and large encourages strong convergence. So, for 
example, at the OWL Experiences and Directions workshop, the users and 
implementors agreed on a core set of features that were useful and easy 
enough to add and should become the new base line (called OWL 1.1):
	http://owl1-1.cs.manchester.ac.uk/

In general, deviations are treated as bugs or as proposals, with a lot 
of emphasis on supporting the same language.

Now, there is somewhat less of a historical burden, so it's a tad 
easier.

It's also interesting how a standard can force changes. Racer went from 
enforcing the unique name assumption (as most DL systems did) to not 
for the sake of OWL compatibility. So it's worth considering 
affordances toward homoginization (instead of being completely bound by 
quirk support).

Cheers,
Bijan.

Received on Thursday, 20 April 2006 03:25:57 UTC