1. Lyon Research Center for Images and Intelligent Information Systems IEEE International Conference on Pervasive Services 2006 FRE 2672 INSA Lyon ICPS, 27 June 2006 Modeling and Using Context in Adapting Applications to Pervasive Environments Tarak Chaari, Dejene Ejigu, Frédérique Laforest and Vasile-Marian Scuturici

2. ICPS 2006 2 OUTLINE Introduction The scope of this paper Context Modeling Adaptation strategy to context Implementation Conclusions

3. ICPS 2006 3 What is context? Fuzzy and general word Where are we? What we are doing? … 1996, Brown’s definition  Location, identity, application and time 2001, Dey’s definition  Any information characterizing an entity  An entity is a person, a location, an object…  The most general and adopted definition  Too vague and it does not help modelling the context

4. ICPS 2006 4 context definition and properties Definition: context is the set of external parameters that can modify the behaviour of an application by defining new views on its data and services Wingorad: something is context because of the way it is used in interpretation, not due to its inherent properties Example: GPS coordinates in a healthcare application / in traffic regulation application Context parameters are transparent to the user New instance = new contextual situation These precisions help adding context – awareness to non adapted application

5. ICPS 2006 5 Context – Awareness Definition  The ability of acquiring context knowledge  adaptation to the context change Requirements  Capture  Interpret  Store/Disseminate  Adapt

6. ICPS 2006 6 Motivations Existing solutions  specific to particular concerns  a lot of interest on how to capture context Lack of a comprehensive context model  formality  expressiveness Lack of a concrete approach to adapt applications to context  generic adaptation strategy  dynamic adaptation

7. ICPS 2006 7 OUTLINE Introduction The scope of this paper Context Modeling Adaptation strategy to context Implementation Conclusions

8. ICPS 2006 8 SECAS Project Simple Environment for Context – Aware Systems Generic and comprehensive platform  Creating new context-aware applications  Adapting existing legacy applications to new contexts

9. ICPS 2006 9 SECAS Architecture

10. ICPS 2006 10 OUTLINE Introduction The scope of this paper Context Modeling Adaptation strategy to context Implementation Conclusions

11. ICPS 2006 11 Context Modeling Context = (Subject, Predicate, Value, Time, Certainty) Example= (Bob, isLocatedIn, room305, Fri-23-jun- 2006-12:00:00-GMT, 0.85) Intelligence and semantics processing  (VideoService, runsOn, PDA-01)  (PDA-02, runs, VideoService)  (realPlayer, runsOn, laptop-01)  devices that can run Video Services

12. ICPS 2006 12 Ontology for context modeling

13. ICPS 2006 13 Example of a context ontology

14. ICPS 2006 14 OUTLINE Introduction The scope of this paper Context Modeling Adaptation strategy to context Implementation Conclusions

15. ICPS 2006 15 Application’s Functional Model Functional Model = application services description + services dependences XML deployment descriptor (extension of pnml)

16. ICPS 2006 16 Service Adaptation strategy

17. ICPS 2006 17 Service adaptation entity Adapter (proxy)

18. ICPS 2006 18 Service adaptation rules Pairs (context situation, adaptation action)  Context situation = Logical expressions of context predicates  Adaptation action = a list of adaptation operators  Operators on the functional model  Operators on the inputs and outputs of services  Operators on service versions Example

19. ICPS 2006 19 OUTLINE Introduction The scope of this work Context Modeling Adaptation strategy to context Implementation Conclusions

20. ICPS 2006 20 SECAS Administration User Interface

21. ICPS 2006 21 Context1: Doctor1 using SICOM on a standard PC

22. ICPS 2006 22 Context2: Doctor1 using SICOM on a smartPhone E1 E2 E3 E4 E5 E6 E’6

23. ICPS 2006 23 OUTLINE Introduction The scope of this paper Context Modeling Adaptation strategy to context Implementation Conclusions

24. ICPS 2006 24 Conclusions A comprehensive Context model based on ontology representation An extensible adaptation platform to:  create context – aware applications  adapt existing applications to context Platform under development  Services adaptation module completed and validated  Content adaptation module  User interface adaptation module

25. ICPS 2006 25 Question time ! ?