[QUANTITY] An object- and domain-oriented proposal in UML and XML

[Giaretta, DL (David)]

Arnold

I certainly agree that we need to be sure that what we come up with is
implementable. However we should be sure that what we produce is not limited
to one specific format, or have some implicit limitation. The ID/IDREF need
not be XML specific but they are rather suggestive, and in particular they
tend to suggest that we are talking about things in a single XML file. 

...David

-----Original Message-----
From: Arnold Rots [mailto:arots at head-cfa.cfa.harvard.edu]
Sent: 28 May 2003 16:20
To: Giaretta, DL (David) 
Cc: 'thomas at adc.gsfc.nasa.gov'; dm at ivoa.net
Subject: Re: [QUANTITY] An object- and domain-oriented proposal in UML
and XML


David,

Just a quick comment on your first point.
I agree that in principle the data model should not be implementation
specific.  However, I think it is important to keep in mind that the
reference mechanism is (should be) available when it comes to a
practical implementation.  Or, put differently: I think it is
reasonable to require implementations to incorporate the capability to
use references; with that in mind, the ID/IDREF part is not really XML
specific.

  - Arnold

Giaretta, DL (David)  wrote:
> Brian
> 
> I'm a little concerned that your paper seems to be an XML specific data
> model - things like the Id and IdRef.
> 
> It seems to me that we should be very clear that the data model should be
> independent of the format of the data. The same data can - and probably
will
> - be represented as FITS, XML, Ascii, etc. We should clearly separate the
> representation from the actual information and one of the tests of the
data
> model must surely be - "does it work if this piece of data is a FITS file"
> and "does it work if the data is pure XML" - and we'd better get an answer
> "yes" for both.
> 
> The Open Archival Information System Reference Model (OAIS)
> (http://wwwclassic.ccsds.org/documents/pdf/CCSDS-650.0-B-1.pdf) - now an
ISO
> standard - carefully distingusihes between Content Information and
> Representation Information and I think this is an important distinction.
> 
> ...David
> 
> 
> 
> -----Original Message-----
> From: Brian Thomas [mailto:thomas at mail630.gsfc.nasa.gov]
> Sent: 27 May 2003 18:33
> To: dm at ivoa.net
> Subject: [QUANTITY] An object- and domain-oriented proposal in UML and
> XML
> 
> 
> 
> 	Hi all,
> 
> 	Ok, since I see others have put together proposals for the simple
> quantity, now
> 	Ed and I have also done so. What is different about this proposal?
> Concisely,
>  	it describes an object- and domain-oriented simple quanties data
> model. We
>  	use these technologies in order to enable a number of important
> requirements,
> 	including the ability for the quantity data model to describe data
> at every data 
> 	repository using machine readable inheritable
> concepts/classes/standards.
> 
> 	Whitepaper is available in a variety of formats from the following
> URLS:
> 
> 	http://nvo.gsfc.nasa.gov/DataModel/VOSimpleQuantityDataModel.html
> 	http://nvo.gsfc.nasa.gov/DataModel/VOSimpleQuantityDataModel.doc
> 	http://nvo.gsfc.nasa.gov/DataModel/VOSimpleQuantityDataModel.sxw
> 
> 	(where the extension tells you what you are dealing with...the last
> is the
>     	openoffice format).
> 
> 
> 					Regards,
> 
> 					=b.t.
> 
> -- 
> 
>   * Dr. Brian Thomas 
> 
>   * Code 630.1 
>   * Goddard Space Flight Center NASA
> 
>   *   fax: (301) 286-1775
>   * phone: (301) 286-6128
> 
> The most serious doubt that has been thrown on the authenticity of the
> biblical miracles is the fact that most of the witnesses in regard to
> them were fishermen.
> 		-- Arthur Binstead
> 
--------------------------------------------------------------------------
Arnold H. Rots                                Chandra X-ray Science Center
Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
60 Garden Street, MS 67                              fax:  +1 617 495 7356
Cambridge, MA 02138                             arots at head-cfa.harvard.edu
USA                                     http://hea-www.harvard.edu/~arots/
--------------------------------------------------------------------------