Natural Language Querying of the Semantic Web

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Natural Language Queryingof theSemantic Web

• SRI International
• Information Science Institute

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QUARK

• Access to multiple knowledge sources
• CIA World Factbook
• NASA data sources
• TextPro IE engine
• ADL Gazetteer
• Natural language front end (Gemini)
• Mediated by powerful reasoning tool (SNARK)
• Visualization capabilities

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Goal To Integrate DAML Search into QUARK

• Agent Semantic Communications Service (ASCS)
• Developed by Teknowledge.
• Searches the Web for DAML pages.
• Provides GUI for search.
• Limited inference capability (broadening and
  relaxation of queries).

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The ASCS Search Page
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ASCS A Use Case
To find the capital of Syria, a user must input
pred
capital
Searches entire Semantic Web
arg1
?x
e
arg2
Syria
Also conjunctive queries population of capital
of Syria
Problem Doesnt support natural language input
using ASCS requires knowledge about logic and
DAML namespaces.
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How do we fit ASCS into Quark

• Questions parsed by Gemini to yield logical form.
• Logical form submitted to theorem prover SNARK as
  conjecture.
• Conjecture proved in application-domain theory.
• Capabilities of ASCS and other sources advertised
  in theory.
• Resources invoked as appropriate by procedural
  attachment.
• Answer, as text or visualization, extracted from
  proof.

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Show the capitals of Islamic countries that
border Iraq.

• Logical form produced by Gemini
• and(
• country (?x)
• islamic (?x)
• bordering-relation (?z)
• goal (?z iraq)
• source (?z ?x)
• capital-of (?u ?x)
• show (?v)
• patient (?v ?u))
• Answer ?v

islamic (?x)
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Conjecture decomposed by SNARK

• To show a country is Islamic, use the axioms in
  the application-domain theory
• if religions (?country1, SunniMuslim, ?percent1)
• and ?percent1 gt 50
• then islamic (?country1)
• A country that is more than 50 percent Sunni
  Muslim is Islamic.

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ASCS Reveals Basic Facts

• borders(Iraq, Syria)
• borders(Iraq, Turkey), ..
• religions(Syria, SunniMuslim, 74)
• religions(Syria, Christian, 10),
• Capital(Syria, Damascus)
• Syria is 74 percent Sunni Muslim.

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Other Agents Reveal other Facts

• Alexandria Digital Library Gazetteer
• place-to-latlong(Damascus, capital, Syria,
• '33.5', '36.3')
• The location of Damascus.

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Answer visualization by Terrain ViewerDamascus
(capital),Syria,'33.5','36.3'
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Future Plans

• Enrich application-domain theory.
• Expand use of ASCS.
• Expand use of textual sources.
• Introduce new knowledge sources.
• Further development of information-seeking
  dialogues.