Re: [uima] Type System Base Model v.4

Karin,

Overall looks good.  I have a comment
about the TextAnnotation and TextRegionalReference definintion.

There are some tricky details regarding
a standard definition of beginChar, endChar.  What exactly do these
values represent - Unicode character offsets?  Note that Apache UIMA
does not use Unicode character offsets, but rather "UTF-16 code unit"
offsets - that is, each element is a 16-bit value like a char in a Java
String.  This has the advantage of allowing constant-time indexing
(e.g. for getCoveredTex).   Unfortunately not all Unicode characters
can be represented in 16 bits, so sometimes a single Unicode character
is split across two 16 bit values.  Apache UIMA doesn't use true Unicode
character offsets in that cases.  This is especially inconvenient
for anyone using UTF-8 rather than UTF-16 (for example, Perl annotators).
 

I'm not sure what the right answer it,
but using "real" Unicode character offsets seems like it's a
more appropriate use of the Unicode standard.  Then, for Apache UIMA
to be compliant does it just need to accept XMI CASes with Unicode offsets
and covert them to its own internal representation?  Or would the
internal representation have to actually change (which would be ugly).

Regards,

  -Adam

_____________________________

 Adam Lally

 Advisory Software Engineer 

 UIMA Framework Lead Developer

 IBM T.J. Watson Research Center

 Hawthorne, NY, 10532

 Tel: 914-784-7706,  T/L: 863-7706

 

Karin Verspoor <>

03/30/2007 01:50 PM

To

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Subject

[uima] Type System Base Model v.4

Please find attached the reviewed document outlining

changes/proposals/action plan for the Type System Base Model.

Comments welcome.

Karin

_______________________________________________________________

Karin Verspoor, Computational Linguist

Knowledge and Information Systems Science team

Computer, Computation & Statistics division

http://public.lanl.gov/verspoor

email:    Mail: Los Alamos National Laboratory

phone: 505-667-5086              PO
Box 1663, MS B256

fax:   505-667-1126              Los
Alamos, NM 87545

_______________________________________________________________

[attachment "TypeSystemBaseModel_v4.doc" deleted by Adam Lally/Watson/IBM]