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<div class="moz-cite-prefix">hi Davide,<br>
<br>
Your summary is quite accurate about my case.<br>
<br>
Thanks for the pointer, I will look in to hybrid chaining once I
do a little investigation on why exactly the original problem
occurred. I'm still having little issues with the 5.5.1 source
compilation (for which your help worked flawlessly to get the
source working, but there were test fails during the compilation.
I will try myself to fix them before asking questions on that).<br>
<br>
As i said, the bigger problem is with the rules that are
transitive in nature. Let's say there is a is_in rule which is
used to derive spacial relationships. For instance, a concrete
example<br>
<br>
is_in (uni_of_michigan, ann_arbor).<br>
is_in(ann_arbor, MI).<br>
is_in(MI, USA).<br>
is_in(A, C) <- is_in(A, B), is_in(B, C).<br>
<br>
I want to deduce (in general course of reasoning) such stuff as
is_in(uni_of_michigan, USA), but if I do it in the regular drools
way, I'd end up with a load of unnecessary deductions. This is the
biggest problem I have. If you want a more involved concrete
example, say I define (for the sake of simplicity)<br>
<br>
romantic(A) <- scenic(A), secluded(A).<br>
scenic(A) <- next_to(A, B), scenic_artefact(B).<br>
scenic_artefact(B) <- lake(B) or waterfall(B) or ... and so on<br>
secluded(A) <- [ situated further than N km from the nearest
city ]<br>
<br>
Now this last rule is where logic gives way to POJO and databases.
It seems to me that this is the most sensible thing to do. Also,
this is as far as I want to go at the moment. (Having known the
non-boolean reasoning ability of drools from your mail, I can
think of many ways I want to use it :) )<br>
<br>
I looked into your profile and saw that you have a background on
the ontologies. Especially what you have mentioned under Drools -
"Open Source Knowledge Integration and Reasoning Platform" in your
university profile seems quite intersting and seems to be exactly
the things I might be needing in the near future. I was thinking
that I'll have to implement non-boolean reasoning using some fuzzy
toolkit, if it becomes available with drools I'll be really happy
to give it a try.<br>
<br>
If you have any material to share for further reading on your
drools research, I'd be grateful.<br>
<br>
Thanks,<br>
Upali<br>
<br>
<br>
On 15/04/2013 03:10, Davide Sottara wrote:<br>
</div>
<blockquote cite="mid:516B2235.4070108@gmail.com" type="cite">
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<div class="moz-cite-prefix">Correct me if I'm wrong, I would
summarize your requirements as follows:<br>
- you need some "A-box" reasoning, but you are fine with a
rule-based approach<br>
- the object-oriented integration Drools provides is quite
convenient<br>
- you have large data sets for which an opportunistic,
"query-oriented" approach<br>
would work better rather than a fully generative "forward
chaining" approach<br>
<br>
Drools "hybrid-chaining" approach could be very useful here -
I'm not sure how<br>
well documented it is, and how you are planning to use it, but
it would be interesting<br>
to see one of your rules - even "stripped" of the details you
don't want to show -<br>
to discuss the behaviour of the engine and its implications.<br>
<br>
I had a use case apparently very similar to yours some time
ago.. I'm working even<br>
now on some experimental forms of rule/object/ontology
integration. The "trait"<br>
feature might be an alternative to the explicit addition of
classes to objects .. it was<br>
enhanced a few days ago to support updates and modifications. <br>
If you have an ontology to begin with, you might also be
interested in the ontology -> class<br>
conversion tool I'm working on even now<br>
<br>
Davide</div>
</blockquote>
<br>
<br>
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