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

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

ICPS 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

ICPS 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

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

ICPS 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

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

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

ICPS SECAS Architecture

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

ICPS Context Modeling Context = (Subject, Predicate, Value, Time, Certainty) Example= (Bob, isLocatedIn, room305, Fri-23-jun :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

ICPS Ontology for context modeling

ICPS Example of a context ontology

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

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

ICPS Service Adaptation strategy

ICPS Service adaptation entity Adapter (proxy)

ICPS 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

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

ICPS SECAS Administration User Interface

ICPS Context1: Doctor1 using SICOM on a standard PC

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

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

ICPS 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

ICPS Question time ! ?