18-12-2012, 06:50 PM
Ontology, Services and Rules
1Ontology,.ppt (Size: 119 KB / Downloads: 22)
RDF
Identify ‘things’ through URIs, and
describe them in terms of simple properties and property values
Triples: subject predicate object
http://www.exampleindex.html
http://purldc/elements/1.1/creator
http://www.examplestaffid/85740
Subjects and objects are viewed as nodes, predicates as links in a graph
Predicates are defined - ontology
rdf:type - objects can have types
a defined predicate
RDFS
RDF Properties: represent relationships between resources
No way to describe these properties, or relationships between these properties and other resources
RDFS: specify Classes and the domain and range of properties:
DAML-O
A DAML+OIL knowledge-base is a collection of RDF triples
DAML+OIL prescribes the meaning of triples that use DAML+OIL vocabulary
Adds 12 classes and 26 properties to RDFS (axiomatised)
DAML-S
Service Model: Process Ontology
Atomic, Simple, Composite Process
Control Construct
Sequence, Split, Choice, If-Then-Else
Data flow/Parameter Bindings
There are no variables in the language to allow instances to be equated
E.g. item1 is input; item1 is output, but we can only specify the type as input/output
Annotation is used:
sameValues(Process, [ (valueOf Class,Parameter),….])