Temporal Ontology

Shervin Daneshpajouhce.sharif.edu/~daneshpajouh

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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Pervasive Computing EnvironmentYesterdayYesterday: Gadget Rules: Gadget Rules

Too bad they can’t talk to each other…

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Pervasive Computing EnvironmentToday: Communication RulesToday: Communication Rules

Configuration? Too much

work…

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Pervasive Computing Environment Tomorrow: Services Will RuleTomorrow: Services Will Rule

Thank God! Everything is done for me!

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Some Scenario

Shopping in Pervasive Computing Office in Pervasive Computing Hospital in Pervasive Computing

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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Ontology

Provide a formal, explicit specification of a shared conceptualization of a domain that can be communicated between people and heterogeneous and widely spread application systems

A formal explicit description of concepts in a domain of discourse (classes), properties of each concept describing various features and attributes of the concept (slot) and restrictions on these properties

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Ontology for Pervasive Computing

Provide meanings for terms when information exchange– Bridge knowledge gaps between different

domains– Enable knowledge sharing in open and dynamic

distributed systems– Allow devices and agents not expressly designed

to work together to interoperate (i.e. better device interoperability)

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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SOUPA

Standard Ontology for Ubiquitous and Pervasive Applications

Agust 2004

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SOUPA

FOAF friend of a friend DAML-Time OpenCyc Spatial Regional Connection Calculus Cobra Mogatu BDI Rei Policy

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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COBRA - Context Broker Architecture

An agent based architecture for supporting context-aware systems in smart spaces (e.g., intelligent meeting rooms, smart homes, and smart vehicles).

Central to this architecture is an intelligent agent called Context broker

Context broker maintains a shared model of context on the behalf of a community of agents, services, and devices in the space and provides privacy protections for the users in the space by enforcing the policy rules that they define.

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Key differences between CoBrA and other similar architectures

CoBrA uses the Web Ontology Language OWL, a W3C Semantic Web standard, to define ontologies of context (people, agents, devices, events, time, space, etc.). In other systems, context is often implemented as programming language objects (e.g., Java classes), lacking the expressive power to support context reasoning and high-level knowledge sharing.

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Context Broker Architecture

CoBrA FeaturesCoBrA Features[1] Use Semantic Web languages for context modeling and reasoning

[2] Use logic inference to detect and resolve inconsistent context knowledge

[3] Extend the REI policy language for privacy protection

[4] Adopt the FIPA standards for communication & knowledge sharing

EasyMeeting an intelligent meeting room prototype that provides services for speakers, audience & organizers based on their situational needs.

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COBRA-ontology

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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Temporal Logic

Our “worlds” are the states in an execution. There is a linear relation between them, each

two sequences in our execution are ordered. Interpretation: over an execution, later over

all executions.

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Temporal Logic

Representing Time– Points in Time– Intervals

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Temporal Logic - Syntax

::= () | ¬ | /\ \/ U |O | p

“box”, “always”, “forever”

“diamond”, “eventually”, “sometimes”

O “nexttime”

U“until”

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Semantics over suffixes of execution

O

U

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Temporal Logic - Combinations

[]<>p “p will happen infinitely often”

<>[]p “p will happen from some point forever”.

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Temporal Logic - Combinations

([]<>p) --> ([]<>q) “If p happens infinitely often, then q also happens infinitely often”.

Mortal = LivingBeing (LivingBeing U [] not LivingBeing) “A living being that is alive until it dies”

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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Ontology And Temporal Logic

Ontologies for pervasive computing environments will require logical models that include spatial and temporal logic, geometry, and other quantitative reasoning.

It is unclear whether DAML+OIL should be extended to include additional logical concepts, or whether other kinds of markup languages should be developed for expressing concepts involving these quantitative aspects.

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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DAML-TIME

Class Hierarchy Thing ()

– TemporalEntity (before*) Instant () Interval (endOf*, inside*, startOf*) Property Hierarchy

– before – endOf – inside – startOf

http://www.ai.sri.com/daml/ontologies/sri-basic/1-0/Time.daml

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DAML-TIME

the temporal properties of Web pages and the temporal properties of Web services.

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Temporal Ontology

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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An Ontology of Time for the Semantic Web

TOPOLOGICAL TEMPORAL RELATIONS– Instants and Intervals– Before– Interval Relations– Linking Time and Events

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An Ontology of Time for the Semantic Web

TOPOLOGICAL TEMPORAL RELATIONS– Instants and Intervals

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An Ontology of Time for the Semantic Web

TOPOLOGICAL TEMPORAL RELATIONS– Before

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Summery

Pervasive Computing Environment Ontology and Pervasive Computing

– SOUPA– COBRA

Temporal Logic Ontology and Temporal Logic

– DAML-TIME– An Ontology of Time for the Semantic Web

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References

Ontologies in a Pervasive Computing Environment SOUPA: Standard Ontology for Ubiquitous and Pervasive

Applications, Harry Chen, Filip Perich, Tim Finin, Anupam Joshi, University of Maryland, Baltimore County, Agust 2004

An Ontology for Context-Aware Pervasive Computing Environments, Harry Chen, Tim Finin, and Anupam Joshi, Department of Computer Science and Electrical Engineering, University of Maryland Baltimore County

Semantic Web in a Pervasive ContextAware Architecture,

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References

Harry Chen, Tim Finin, Anupam Joshi, University of Maryland Baltimore County

Description Logic Handbook, chapter 6, Extensions to Description Logics

Reasoning about Temporal Context using Ontology and Abductive Constraint Logic Programming, Hongwei Zhu, Stuart E. Madnick, Michael D. Siegel, 2004

Toward an Ontology of Time for the SemanticWeb, Jerry R. Hobbs 2004

The Specification Language TimeML, James Pustejovsky, Robert Ingria, Roser Saur´ı, Jos´e Casta˜no, Jessica Littman, Rob Gaizauskas, Andrea Setzer, Graham Katz, Inderjeet Mani, 2004

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References

An Ontology of Time for the Semantic Web, JERRY R. HOBBS and FENG PAN, 2004

Temporal Aggregates in OWL-Time, Feng Pan and Jerry R. Hobbs, 2005

IEEE First Annual International Conference on Mobile and Ubiquitous Systems: Networking and Services

Second IEEE Annual Conference on Pervasive Computing and Communcations Workshops-2004

http://www.ai.sri.com/daml/ http://cobra.umbc.edu http://swoogle.umbc.edu/ http://ebiquity.umbc.edu/

Any Question?

Thanks for your attention.