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Re: Proposed extensions to OWL?

From: Thomas B. Passin <tpassin@comcast.net>
Date: Mon, 16 Jun 2003 09:43:21 -0400
To: www-rdf-interest@w3.org
Message-id: <002901c3340d$40c3aa50$6401a8c0@tbp1>

[Jon Hanna]
>
> Thinking about this I'm struck my the notion that the model of the example
> is wrong, a line doesn't have a cm length and a in length, it has a single
> length which can be described in either cm or in.
>

That is what I meant in my recent post, though you have expressed it more
simply.

[Danny Ayers said]
> I must admit I'm also not entirely sure of the value of being able to
> express this particular kind of equivalence/operation (like units-cm =
> 2.54*units-inch) in the first place, I would have expected the role of OWL
> to express just that it was a "units conversion operation" and to help
> locate a service that could deal, rather than handling any operation
itself.


I agree, if we want to find a web service to convert from inches to
centimeter we may be talking about a process.  But I have a lot of trouble
with the thought that I need to invoke a web service every time I want to do
a lousy little units conversion!

But I was not thinking of actually making a transformation but of
determining equivalence.  If I get a statement from one source that a
particular refrigerator is 76.2 cm wide, and from another source that it is
30 inches wide - or needs to fit into a space 30.5 inches wide - I would
like to be able to know if they are compatible or not.  Granted, I could
operationally test that by making the calculation.  Or I could compute the
scaling factor and see if it agrees with the known value.  There are many
procedures I could use, but just one underlying relationship.  I would
rather capture the underlying notion than encode one specific procedure for
applying it, if I could.

Cheers,

Tom P
Received on Monday, 16 June 2003 09:42:12 GMT

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