KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Vorlesung Knowledge Discovery - Institut AIFB

Tempus fugitTowards an Ontology Update LanguageUta LöschSebastian RudolphDenny VrandečićRudi Studer

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Agenda

(i) Motivation

(ii) Framework

(iii) Example

(iv) Summary / Outlook

KIT- die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH) 2

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

The world changes…

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PhD student PhD

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Ontologies change…

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Vorlesung Knowledge Discovery - Institut AIFB4

Is the ontology changed due to an according change in the described domain?

Ontology repair

Ontology amendment

Ontology update

yesno

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

The world changes…

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PhD student PhD

Changes are:Expected

Match a recurring patternRequire additional changes

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Motivating example

Vorlesung Knowledge Discovery - Institut AIFB6

PhilippThanh

supervises

leadsworksOn

XMedia Multipla

worksOn

AIFB

affil

affil

affil

affil

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Idea

Develop an update mechanism that Exploits domain-specific knowledge Exploits the patterns exhibited by many updates Automates additional changes that are required Associates process knowledge with the ontology

Vorlesung Knowledge Discovery - Institut AIFB7

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Why not use…

Belief revision? Mechanisms triggered if ontology turns inconsistent Unintended state ≠ inconsistent state Domain –independent

Ontology evolution? Mechanisms that define reactions to changes Operates on generic constructs (e.g. classes) Domain-independent

Vorlesung Knowledge Discovery - Institut AIFB8

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Agenda

(i) Motivation

(ii) Framework

(iii) Example

(iv) Summary / Outlook

KIT- die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH) 9

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Framework

Ontology

KnowledgeWorker

Ontology Update

Manager

Check applicability

Apply changes

Ontology Update

SpecificationFind specification

KnowledgeEngineer

Feedback

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Definition of change handlers

CREATE CHANGEHANDLER <name>FOR <changerequest>AS[ IF <precondition> THEN ] <actions>

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KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Definition of change handlers

Change request SPARQL select query Evaluated against the graph that is to be added or

removed from the knowledge base Precondition

Syntactic preconditions: Does the knowledge base contain the triples defined in the precondition?

Semantic preconditions: Does the knowledge base entail the triples defined in the precondition?

EntailsChanged preconditions: Does the knowledge base after applying the change entail the triples defined in the precondition?

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KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Definition of change handlers

Actions Apply request SPARQL update Loop action (for ( <preconditions> actions end) Feedback action

Variables may be defined in the change request and the precondition – are bound whenever used afterwards

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KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Instantiation

Based on RDF(S) and SPARQL Update Wrapper for SPARQL endpoint

Reference implementation based on Jena available at:http://www.aifb.uni-karlsruhe.de/WBS/uhe/OUL/

Vorlesung Knowledge Discovery - Institut AIFB14

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Agenda

(i) Motivation

(ii) Framework

(iii) Example

(iv) Summary / Outlook

KIT- die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH) 15

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

The example revisited

Vorlesung Knowledge Discovery - Institut AIFB16

PhilippThanh

supervises

leadsworksOn

XMedia Multipla

worksOn

AIFB

affil

affil

affil

affil

delete( Philipp affil AIFB )

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Example

CREATE CHANGEHANDLER leavesInstitutionFOR delete { ?x affil ?y }AS applyRequest;

feedback("?x is no longer affiliated to ?y");for(contains(?x supervises ?z . ?z affil ?y))

delete data {?x supervises ?z};feedback("Thus, ?x does not supervise ?z

anymore"); end;

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delete( Philipp affil AIFB )

x = Philipp, y = AIFB

„Philipp is no longer affiliated to aifb.“

Philipp supervises ?z. ?z affil AIFB.

delete( Philipp affil AIFB )

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

The example revisited

Vorlesung Knowledge Discovery - Institut AIFB18

PhilippThanh

supervises

leadsworksOn

XMedia Multipla

worksOn

AIFB

affil

affil

affil

affil

delete( Philipp affil AIFB )

?z = Thanh

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Example

CREATE CHANGEHANDLER leavesInstitutionFOR delete { ?x affil ?y }AS applyRequest;

feedback("?x is no longer affiliated to ?y");for(contains(?x supervises ?z . ?z affil ?y))

delete data {?x supervises ?z};feedback("Thus, ?x does not supervise ?z

anymore"); end;

Vorlesung Knowledge Discovery - Institut AIFB19

delete( Philipp affil AIFB )

x = Philipp, y = AIFB,z = Thanh

„Philipp is no longer affiliated to aifb

Philipp supervises ?z. ?z affil AIFB.

Philipp supervises Thanh

„Thus Philipp does not supervise Thanh

anymore.“

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Motivating example

Vorlesung Knowledge Discovery - Institut AIFB20

PhilippThanh

supervises

leadsworksOn

XMedia Multipla

worksOn

AIFB

affil

affil

affil

affil

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Agenda

(i) Motivation

(ii) Framework

(iii) Example

(iv) Summary / Outlook

KIT- die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH) 21

KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Summary & Outlook

Summary: Framework for handling updates in a guided,

domain-specific manner Implementation for RDF(S) and SPARQL Update

Outlook: Extend mechanism to OWL Interactivity for choosing between several

matching change handlers

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KIT – die Kooperation von Forschungszentrum Karlsruhe GmbH und Universität Karlsruhe (TH)

Thank you!Questions?

uta.loesch@aifb.uka.de

Vorlesung Knowledge Discovery - Institut AIFB23