Re: XG W3pm Scope

Dear All,

Michel's three top items seem to be a good starting point. (Another minor
procedural point - I would like to suggest using N3 rather than XML for RDF
examples wherever possible.)

I have some initial thoughts on quantities and units, as follows:

Quantities and Units
--------------------
Introduction
------------
A good starting for looking at Quantities and Units is "An Ontology for
Engineering Mathematics", Thomas R. Gruber and Gregory R. Olsen, 1994,
http://www-ksl.stanford.edu/knowledge-sharing/papers/engmath.html.

Summarising some of the key concepts we have:
- physical quantity as defined in ISO 31, e.g. length of 10 metre,
thermodynamic temperature of 20 degrees Celsius 
- spaces of related physical quantities, e.g. length, thermodynamic temperature
- defined points (units) within a space of physical quantities, e.g.
the_metre, the_Kelvin 
- scales which relate spaces of physical quantities to real numbers, e.g.
metre_scale, Kelvin_scale, Celsius

An issue which causes some problems is the relationship between units (e.g.
the_metre, the_Kelvin) and scales (e.g. metre_scale, Kelvin_scale, Celsius).
Gruber and Olsen point out that they can be related by lambda calculus.

The concepts in RDF
-------------------
If we are happy that a mathematical structure, such as manifold, metric
space, vector space, etc., is an owl:Class (a big "if"), then we can say:

:PhysicalQuantitySpace    rdfs:subClassOf owl:Class .

:Length                   a               :PhysicalQuantitySpace .
:ThermodynamicTemperature a               :PhysicalQuantitySpace .

:TheMetre                 a               :Length .
:TheKelvin                a               :ThermodynamicTemperature .

:metreScale               a               owl:DatatypeProperty 
                          rdfs:domain     :Length . 

:kelvinScale              a               owl:DatatypeProperty 
                          rdfs:domain     :ThermodyanmicTemperature .

:celsius                  a               owl:DatatypeProperty 
                          rdfs:domain     :ThermodyanmicTemperature .

Recording the relationship between :TheMetre and :metreScale requires
MathML, or an RDF version of it. The following are true statements by
definition:

:TheMetre                 :metreScale     1 .
:TheKelvin                :kelvinScale    1 .

An example
----------
If we assume that waterline length is a property of a ship, then we can
define it as:

:waterlineLength          a               owl:FunctionalProperty ;
                          rdfs:domain     :Ship ;
                          rdfs:range      :Length .

and make the statement:

:MyShip :waterlineLength [ :metreScale 10 ] .

Ownership of concepts
---------------------
Within ISO, I am trying to get ISO TC184/SC4 and other technical committees
to assign URIs to the objects they define. The concepts of
PhysicalQuantitySpace, Length and ThermodynamicTemperature are all defined
in ISO 31, and it would be good if they were assigned a URI by ISO 31.

The concepts of TheMetre, TheKelvin and Celsius are defined by BIPM, and it
would be good if they were assigned a URI by BIPM. It is not clear to me who
owns the concept of metreScale. Perhaps it is BIPM also.

Perhaps the Incubator Group, with ISO TC184/SC4, could approach ISO and BIPM
to get these URIs assigned by the organisations that define the concepts.

The RDF formala which describes the relationships between the concepts can
then be published by W3C.

Best regards,
David 

At 14:33 29/05/2008 +0200, you wrote:
>Dear All,
> 
>Hereby I send you a first input/scope document for our XG  on Product
Modelling. Please comment before the end of next week. Please comment
globally that is:
>- advice more potential modules
>- say something about the importance of modules
>- comment the current global ideas/notions
>- add such notions without going in detail
> 
>The idea is that after processing your comment I can make a scope document
that we can all agree on. Next we can start the actual work/discussion on
the prioritized modules in more detail at some KO telcon.
> 
>The idea was to send this mail only to the member list but since there are
still quite some TO-BE members (I only received a request for invited expert
from David Leal sofar) I decided to use the public list to reach all
interested (it's a scope thing anyway..).
> 
>Looking forward to your feedback,
> 
>Michel Böhms
> 
> 
>tno.nl <blocked::blocked::http://www.tno.nl/> 
>
>Dr H.M. (Michel) Böhms MSc
>Consultant Building Innovation 
>
> 
>
>Van Mourik Broekmanweg 6, P.O. Box 49, NL-2600 AA Delft, The Netherlands
>
>T +31 15 2763107
>
>F +31 15 2763024
>
>M +31 6 30381220
>E  michel.bohms@tno.nl <blocked::blocked::mailto:michel.bohms@tno.nl>  
>
>Disclaimer
<http://www.tno.nl/content.cfm?&context=overtno&content=overtnosub&laag1=282
&item_id=72&Taal=2>  

============================================================
David Leal
CAESAR Systems Limited
29 Somertrees Avenue
Lee London SE12 0BS
tel:      +44 (0)20 8857 1095
mob:      +44 (0)77 0702 6926
e-mail:   david.leal@caesarsystems.co.uk
web site: http://www.caesarsystems.co.uk
============================================================

Received on Friday, 30 May 2008 10:30:10 UTC