FRE 2672 Modeling and Using Context in Adapting

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

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

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 2006 3

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 2006 4

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

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 2006 6

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

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 2006 8

SECAS Architecture ICPS 2006 9

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

Context Modeling Context = Certainty) (Subject, Predicate, Value, Time, Example= (Bob, is. Located. In, room 305, Fri-23 -jun 2006 -12: 00 -GMT, 0. 85) Intelligence and semantics processing (Video. Service, runs. On, PDA-01) (PDA-02, runs, Video. Service) (real. Player, runs. On, laptop-01) devices that can run Video Services ICPS 2006 11

Ontology for context modeling ICPS 2006 12

Example of a context ontology ICPS 2006 13

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

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

Service Adaptation strategy ICPS 2006 16

Service adaptation entity Adapter (proxy) ICPS 2006 17

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 2006 18

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

SECAS Administration User Interface ICPS 2006 20

Context 1: Doctor 1 using SICOM on a standard PC ICPS 2006 21

Context 2: Doctor 1 using SICOM on a smart. Phone E 1 E 2 E 5 ICPS 2006 E 3 E 6 E 4 E’ 6 22

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

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 2006 24

Question time ! ? ICPS 2006 25