[higgins-dev] Proposed changes to higgins.owl v15

["Paul Trevithick" <paul@xxxxxxxxxxxxxxxxx>]

Proposed changes to
http://www.eclipse.org/higgins/ontologies/2006/higgins.owl. 

1. Changes related to F2F discussions, IdAS API, etc.
-----------------------------------------------------

* Rename existing Attribute class to "Value" 

* New class created to allow (from at the *IdAS* level is called "metadata
on Attributes"):

<owl:Class rdf:ID="Attribute">
  <rdfs:comment>Instances of this class are used as the domain of
higgins:metadata properties that, taken together, are considered to be the
metadata about a higgins:attribute sub-property. 
  </rdfs:comment>
</owl:Class>

* This Attribute is a new construct (not to be confused with the
higgins:Attribute in v15). It is needed to create some examples of how one
can use this new higgins:Attribute to hold metadata for what, at the HOWL
level, an entire set of values of a higgins:attribute sub-property. For
example this could allow us to hold the "modifiedTime" on the _set_ of two
values of eyeColor, "blue" and "green". 


2. Better way to express relations and correlations.
-----------------------------------------------------
* The following changes don't change the intended semantics, just a cleaner
use of OWL constructs. Instead of modeling inter-subject relationships
ALWAYS using the higgins:attribute property and using either
SubjectRelalationship instances or Correlation instances as its range
(value), we use one of two alternative sub-properties of higgins:attribute
(namely, higgins:relation and higgins:correlation) and ALWAYS use instances
of SubjectRelationship as their ranges (values). This is more consistent.

* Delete Correlation class

* Add:

<owl:ObjectProperty rdf:ID="relation">
  <rdfs:subPropertyOf rdf:resource="#attribute"/>
  <rdfs:comment>A directed relation between two Digital Subjects
  </rdfs:comment>
  <rdfs:range rdf:resource="#SubjectRelationship"/>
</owl:ObjectProperty>

* Add:

<owl:ObjectProperty rdf:ID="correlation">
  <rdfs:subPropertyOf rdf:resource="#relation"/>
  <rdfs:comment>A directed relation between two Digital Subjects believed to
represent the same underlying Entity
  </rdfs:comment>
  <rdfs:range rdf:resource="#SubjectRelationship"/>
</owl:ObjectProperty>

3. Two new kinds of metadata
----------------------------
* During the F2F these two kinds of metadata were mentioned during
discussions of other topics.

<owl:ObjectProperty rdf:ID="creator">
  <rdfs:domain rdf:resource="#Value"/>
  <rdfs:range rdf:resource="#SubjectRelationship"/>
  <rdfs:subPropertyOf rdf:resource="#complexMetadata"/>
</owl:ObjectProperty>

<owl:DatatypeProperty rdf:ID="creationTime">
  <rdfs:domain rdf:resource="#Value"/>
  <rdfs:range rdf:resource="&xsd;date"/>
  <rdfs:subPropertyOf rdf:resource="#simpleMetadata"/>
</owl:DatatypeProperty>