Dear Sean, (01)
I agree with you when you say:
> It may be worth considering separating out the concept of position from the
>representation of position, to allow for position to be represented using
>multiple co-ordinate systems or geographic regions. (02)
We must remember that WGS84 does two things - it defines a geometric
space (within which the earth is more or less at rest), and it
defines a coordinate system for identifying points within it. (03)
TAI (International Atomic Time) is analogous - it defines a temporal
space (defined by a set of clocks at particular positions within the
earths gravitational field), and it identifies instants within it. (04)
Best regards,
David (05)
At 20:22 25/10/2010, you wrote: (06)
> The problem is not just to record co-ordinates, but to do something with
>them. This means identifying services that can evaluate poistion functions,
>such as computing proximity, comparing regions, converting between
>co-ordinates and place names, or following through the hierarchy of
>administrative districts.
>
> Also, given that there are a large number of co-ordinate systems actually
>in use (often based on different shapes for the Earth), there
> will also be a requirement for services to convert between different
>co-ordinate systems.
>
> It may be worth considering separating out the concept of position from the
>representation of position, to allow for position to be represented using
>multiple co-ordinate systems or geographic regions.
>
>
> Sean Barker
>Bristol, UK
>
>
> > -----Original Message-----
> > From: ontolog-forum-bounces@xxxxxxxxxxxxxxxx
> > [mailto:ontolog-forum-bounces@xxxxxxxxxxxxxxxx] On Behalf Of John F.
> > Sowa
> > Sent: 25 October 2010 14:20
> > To: ontolog-forum@xxxxxxxxxxxxxxxx
> > Subject: Re: [ontolog-forum] GPS coordinates in an ontology?
> >
> >
> > *** WARNING ***
> >
> > This message has originated outside your organisation,
> > either from an external partner or the Global Internet.
> > Keep this in mind if you answer this message.
> >
> >
> > On 10/25/2010 8:48 AM, Joshua Lieberman wrote:
> >> Depending on the required precision, GPS coordinates may or may not be
> >
> >> something to enshrine in a static ontology, and a GPS point may or may
> >
> >> not be the appropriate geometric representation.
> >
> > I strongly agree.
> >
> > Every application is likely to need other domain-dependent
> > representations, such as a street address. And it is also likely to
> > need various transformations, such as deriving speed down those roads
> > and streets.
> >
> > All the units of measure are interrelated, and the ontology should
> > include all of them.
> >
> > John
> >
>
>
>
>_________________________________________________________________
>Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
>Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
>Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
>Shared Files: http://ontolog.cim3.net/file/
>Community Wiki: http://ontolog.cim3.net/wiki/
>To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
>To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
> (07)
============================================================
David Leal
CAESAR Systems Limited
registered office: 29 Somertrees Avenue, Lee, London SE12 0BS
registered in England no. 2422371
tel: +44 (0)20 8857 1095
mob: +44 (0)77 0702 6926
e-mail: david.leal@xxxxxxxxxxxxxxxxxxx
web site: http://www.caesarsystems.co.uk
============================================================ (08)
_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx (09)
|