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.