[kepler-dev] EML Unit information in Kepler

[Shawn Bowers]

At a high level, this seems to be a symptom of major weakness of Kepler
today. In particular, the Kepler/Ptolemy framework has no explicit support
or notion of data and metadata, except through actors and the passing of
low-level "tokens".

-shawn


On Wed, 27 Sep 2006, Dan Higgins wrote:

> Hi Matt,
>
>     During my recent discussions with Akiko Ogawa, a limitation in the
> current EML2 dataSource actor came up. The basic problem is that with
> the current implementation, there is no way to programatically  get the
> units of attributes! The ports are automatically created and type
> information (e.g. ints, doubles, etc) assigned, but Akiko wanted to have
> the units of each attribute available so that unit conversion could
> automatically take place. [The hope was to have actual unit info and
> desired unit info available as inputs to an actor that could convert the
> actual units to the desired unit for output to some model. This would
> involve reading the actual unit from EML and having the actor figure out
> how to convert it to the desired unit and then apply that conversion to
> all of the data referred to be the EML attribute.]
>
>     Clearly this unit question is similar to that for any type of
> metadata. How do we do automatic conversion? Units are iust a obvious
> case. Unfortunately, our EML2 DataSource actor does not provide any of
> the unit information.
>
>     I am not at all sure how we should/could provide this unit
> information. Will it come with the semantic annotations tied to
> measurement ontologies, or is it a special case that we could handle
> some other way (especially for EML2 actors where the information is
> already in the EML metadata). I think it is a feature that Akiko would
> like to see in Kepler as soon as possible, so I a am suggesting that we
> give it some consideration in the near future.
>
> Dan
>
> --
> *******************************************************************
> Dan Higgins                                  higgins at nceas.ucsb.edu
> http://www.nceas.ucsb.edu/    Ph: 805-893-5127
> National Center for Ecological Analysis and Synthesis (NCEAS) Marine Science Building - Room 3405
> Santa Barbara, CA 93195
> *******************************************************************
>
>
> _______________________________________________
> Kepler-dev mailing list
> Kepler-dev at ecoinformatics.org
> http://mercury.nceas.ucsb.edu/ecoinformatics/mailman/listinfo/kepler-dev
>