Temporal Ontology Shervin Daneshpajouh ce.sharif.edu/~daneshpajouh

12 April /1/23 2 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

12 April /1/23 3 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

12 April /1/23 4 Yesterday : Gadget Rules Pervasive Computing Environment Yesterday : Gadget Rules Too bad they can’t talk to each other…

12 April /1/23 5 Today: Communication Rules Pervasive Computing Environment Today: Communication Rules Configuration? Too much work…

12 April /1/23 6 Tomorrow: Services Will Rule Pervasive Computing Environment Tomorrow: Services Will Rule Thank God! Everything is done for me!

12 April /1/23 7 Some Scenario Shopping in Pervasive Computing Office in Pervasive Computing Hospital in Pervasive Computing

12 April /1/23 8 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

12 April /1/23 9 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

12 April /1/23 10 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)

12 April /1/23 11 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

12 April /1/23 12 SOUPA Standard Ontology for Ubiquitous and Pervasive Applications Agust 2004

12 April /1/23 13 SOUPA FOAF friend of a friend DAML-Time OpenCyc Spatial Regional Connection Calculus Cobra Mogatu BDI Rei Policy

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12 April /1/23 15 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

12 April /1/23 16 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.

12 April /1/23 17 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.

12 April /1/23 18 Context Broker Architecture CoBrA 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.

12 April /1/23 19 COBRA-ontology

12 April /1/23 20 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

12 April /1/23 21 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.

12 April /1/23 22 Temporal Logic Representing Time – Points in Time – Intervals

12 April /1/23 23 Temporal Logic - Syntax  ::= (  ) | ¬  |  /\   \/  U   |O  | p  “box”, “always”, “forever”  “diamond”, “eventually”, “sometimes” O  “nexttime”  U  “until”

12 April /1/23 24 Semantics over suffixes of execution   O   U        

12 April /1/23 25 Temporal Logic - Combinations []<>p “p will happen infinitely often” <>[]p “p will happen from some point forever”.

12 April /1/23 26 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”

12 April /1/23 27 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

12 April /1/23 28 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.

12 April /1/23 29 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

12 April /1/23 30 DAML-TIME Class Hierarchy Thing () Thing – TemporalEntity (before*) TemporalEntitybefore Instant () Instant Interval (endOf*, inside*, startOf*) Property Hierarchy IntervalendOfinsidestartOf – before before – endOf endOf – inside inside – startOf startOf 0/Time.daml

12 April /1/23 31 DAML-TIME the temporal properties of Web pages and the temporal properties of Web services.

12 April /1/23 32 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

12 April /1/23 33 An Ontology of Time for the Semantic Web TOPOLOGICAL TEMPORAL RELATIONS – Instants and Intervals – Before – Interval Relations – Linking Time and Events

12 April /1/23 34 An Ontology of Time for the Semantic Web TOPOLOGICAL TEMPORAL RELATIONS – Instants and Intervals

12 April /1/23 35 An Ontology of Time for the Semantic Web TOPOLOGICAL TEMPORAL RELATIONS – Before

12 April /1/23 36 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

12 April /1/23 37 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,

12 April /1/23 38 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

12 April /1/23 39 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

Any Question? Thanks for your attention.