Re: [egov] Tactics on data alignment / standardization

[Eliot Christian <echristi@usgs.gov>]

At 09:46 PM 7/23/2003 -0400, David RR Webber wrote:
>Carl,
>
>On quick inspection you deserve an award for the most complex
>XML application I have seen, and also for using the most
>complex parts of the W3C specifications.

To me, it seems the GML approach is to use XML Schema as a tool for
representing semantic relationships as well as data type syntax. So,
a "polygon" is not merely defined in terms of its syntax as a set of
coordinate pairs, but it is derived from a chain of abstract types
that mark higher levels of geometric abstraction. That's not wrong
in itself, expect that it makes the whole structure fiendishly
difficult to handle and very obtuse to understand. IMHO, GML
could employ a simple XML Schema type system supplemented by
an ISO 11179 semantic register.

BTW, for those interested in emergency management, the OASIS EM TC
is now testing the Common Alerting Protocol (CAP) and there is a
rendition of alerts as a GML "FeatureCollection" (aka "map layer").

Eliot