1. Contexts and Importing in RDF
Jie Bao, Li Ding, and Deborah L. McGuinness
Tetherless World Constellation
Rensselaer Polytechnic Institute
Troy, NY, 12180-3590, USA
{baojie,dingl, dlm}@cs.rpi.edu
3. Context Matters
- Assumptions
rdf:type
foaf:mbox owl:InverseFunctionalProperty
ISWC
Jie Bao foaf:mbox
baojie@cs.rpi.edu
J. Bao foaf:mbox
Foo forum
janesmith456 foaf:mbox
n/a
johnsmith123 foaf:mbox
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4. Context Matters
- “World”
“Matrix”
“Real World”
South Park
killed
THEY Kenny
rdf:type rdf:type
Fictional People
0100010111010101010101010…
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5. Contexts are
• Something related to the meaning of a sentence
– Provenance (who, when, where, how, etc)
– Assumptions (e.g., OWA, UNA)
– World
– …
• Claim: when a triple is published/reused/inferred,
its context should be made explicit.
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6. Wait
• Don’t we already have
– Named graph
– C-OWL
– N3 quotation
– Contexts in AI
–…
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7. Named Graph
Name = context
Contexts are more than
names
Graph_RPI
• One triple may be in
{:LiDing :hasRole multiple contexts
:ResearchScientist.} • One context may be
reused
• Relations between
contexts need to be
explicit, too.
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8. C-OWL
South Park
• C-OWL provides an
People ontology mapping
language that respects
contexts.
into
• Knowledge transfer is
RealWorld controlled.
Fictional People
• Contexts are more than
mapping
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9. N3Logic
rpi:LiDing says • Again, contexts are
{rpi:LiDing :hasRole more than quotation.
:ResearchScientist.}
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10. Our Proposal
• Based on named graph
• Add two constructs
• rdf:context
• rdf:imports
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11. Adding Contexts to RDF
Part I: rdf:context Part II: rdf:import
G1 rdf:imports G2.
G rdf:context C. G1 rdf:context C1.
G2 rdf:context C2.
C may give a context • Importing as citation
definition document • How knowledge G2 to G1
transferred from
C agent LiDing. can be controlled by
relations between C1 and
C semantics OWL_Full C2.
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13. Reasoning with Contexts
Context relations Context rules
• Compatible • C is compatible with
• Incompatible contexts with agent
• Extend “rpi:LiDing”
• In • C is compatible with
contexts that are
compatible with C2
Can be specified in OWL,RIF
or other languages
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14. Open Issues
• Context specification
– Provenance model?
– Context relation vocabulary?
• Formal semantics of contexts
• Default contexts
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