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International Virtual Observatory Alliance
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VOResource V0.8.3: an Overview of a Resource Data Model
Ray Plante (NCSA/UIUC)
5 October 2003
Abstract
This VOResource schema defines the IVOA Resource Metadata in XML. The
core metadata, which applies to all resources, is defined in
VOResource-vxxx.xsd. Specialized resource classes, such as
Organization and DataCollection, are defined in
extension schemas. This overview describes version 0.8.3, listing the
changes from v0.8.2 and describing the overall structure of the
schemas.
Contents
- 1. Files to Review
- 2. Overview of Changes
- 3. Data Model Structure
- 4. Current Issues
-
1. Files to Review
This new version of the Resource data model is split between a core schema,
VOResource, and several extension schemas, defined in separate
schemas. The schemas are:
The following two extensions are examples of extensions that define
two standard sky services. These are included for indicative
purposes only.
An example describing several resources, including an
Organisation, two Authoritys, a DataCollection,
and three Services, associated with the
NCSA
Astronomy Digital Image Library (ADIL):
2. Overview of Changes
VOResource:
- set the minimum mandatory elements for
describing a Resource.
- dropped ManagedResource; sub-classes now derive directly
from Resource.
- Facility and Instrument moved from core Resource
metadata to specialized sub-classes.
- added Resource attributes, created, updated, and
status, used by registries to manage resource
descriptions.
- added Source element.
- moved Description, ReferenceURL, and Source as
children of new element Summary.
- Restructured Interface contents.
- added optional LogicalIdentifier
- dropped Contact/Address and Contact/Phone.
- corrected misspelling of "categoryType"
- added "Other" and "DataTransformation" to possible
Types.
- made RelatedTo a ResourceReferenceType, allowing
Title, Description, and ReferenceURL to be
included.
- changed names of Relationship types to match RM.
- added role attribute to Date allow multiple
Dates.
VOCommunity
- Dropped Manages from Organisation
- added Facility and Instrument to Organisation
VODataService
- added Access/AccessURL to DataCollection
- added Facility and Instrument to SkyService
- changed ParamHTTPGet to ParamHTTP (supporting
Post as well).
- added VOTableColumns
3. Data Model Structure
Follow the
element name links for detailed documentation on that element.
- The generic
Resource describes any thing that is describably
and identifiable.
- The minimum mandatory elements include:
- Arrow denotes an "is-A" relationship, e.g. a
Service is a
Resource.
- defined in VODataService-v0.3.xsd
- adds Coverage, Resolution, and
Access
to a
Resource.
- Coverage draws on the Space-Time Coordinates metadata.
-
AccessURL can hold URL to file or directory for trivial
(non-service-based) downloads.
4. Current Issues
- Spatial coverage from the STC is not yet incorporated.
- Facility and Instrument reserved for
Resource subclasses: Organisation,
Project, DataCollection, and
SkyService
- LogicalIdentifier
Last modified: Tue Apr 22 13:09:50 2003
