90 likes | 250 Views
History of Context-Aware Computing. 1991 the term ‘pervasive’ introduced by Weiser 1992 Active Badge Location System (one of the first context-aware systems) User’s location -> forward phone calls to a telephone close to the user
E N D
History of Context-Aware Computing • 1991 the term ‘pervasive’ introduced by Weiser • 1992 Active Badge Location System (one of the first context-aware systems) • User’s location -> forward phone calls to a telephone close to the user • 1994 the term ‘context-aware’ introduced by Schilt, Theimer • User’s location, identities of nearby people, objects and changes to objects • 1996 Brown’s definition of context • elements of the user’s environment which the computer knows about • 1997 Example of Logic based context model: McCarthy and Buvac • 1997 Ryan’s definition of context • user’s location, environment, identity and time
History of Context-Aware Computing • 1997 location-aware tour guide by Abowd • Providing information according to user’s current location • 1998 location-aware tour guide by Sumi • Providing information according to user’s current location • 1998Dey’s definition of context • user’s emotional state, focus of attention, location, orientation, date and time, as well as objects and people in the user’s environment • 2000 location-aware tour guide by Cheverst • Providing information according to user’s current location • 2000Dey and Abowd’s definition of context • “any information that can be used to characterize the situation of entities between a user and an application, including the user and the application themselves” • Proposed criteria for a reasonable architectural approach
History of Context-Aware Computing • 2000Budzik and Hammond’s Watson Project • 2000 W3C, RDF available • 2000 Location-aware systems: Priyantha • 2001 Location-aware systems: Espinoza • 2001Dey and Abowd : • Entities: places, people, things • Attributes: identity, location, status, time • Widgets • 2001 Finkelstein’s IntelliZap • 2001 Winograd : • describes three different context management models for conordinating multiple processes and components – Widgets, Networked services, Blackboard model • 2001 Hong and Landay • Networked services – (resembles the context server architecture) • 2001 Example of Markup scheme models: User Agent Profile (UAProf) • 2001 Dey and Abowd’s Context Toolkit • p2p architecture + centralized discoverer, attribute-value tuple/XML - Context aggregation/interpretation, historical context data, Context Ownership (Privacy)
History of Context-Aware Computing • 2002 Location-aware systems: Burrell and Gay • 2002 Hofer’s Hydrogen • local/remote context, Object Oriented Model, process higher-level context abstraction in application layer • 2002Gustavsen classifies context instances into • External: refers to context that can be measured by sensors/hardwares • Internel: mostly specified by the user or captured by monitoring user interaction • 2002 Hofer classifies context instances into • physical & logical • 2002 Location-aware systems(indoor): Harter • 2002Dey and Abowd: Layered conceptual framework for context-aware systems
History of Context-Aware Computing • 2002 Roman’s Gaia project – extends operating system contepts to include context-awareness • 4-ary predicates in DAML+OIL, context processing is based on first-order logic operation • 2003 Context-aware infrastructure: Munoz (hospital) • 2003 Burnett classifies context instances into external & internel • 2003Indulska and Sutton classified sensors in three groups • physical sensors, virtual sensors, logical sensors • 2003 Example of Graphical Models: Hendricksen’s ORM • 2003Korpipaa presents requirements and goals of context ontology • simplicity, flexibility and extensibility, genericity, expressiveness • 2003 Koripaa’s Context Managing Framework • centered server • 2003 Chen’s CoBrA(Context Broker Architecture) • intelligent space, Broker federation – Avoiding bottleneck, COBRA-Ont, Inference Engine, historical context data, Context Knowledge base – you can assert, delete, modify, query the stored data(API), flexibile policy language to control context access called Rei (privacy) • 2004 W3C, OWL available
History of Context-Aware Computing • 2004 Location-aware systems: Kerer • 2004 Chen presents three different approaches how to acquire contextual information • Direct sensor access, Middleware infrastructure, Context Server • 2004 Example of Markup scheme model • W3C, Composite Capabilities/Preference Profile (CC/PP) • 2004Strang and Linnhoff-Popien summarized the relevant context modeling approaches • 2004Gu’s SOCAM(Service-Oriented Context-Aware Middleware) • centered server-upper ontology, domain-specific ontology, reasoning engine, historical context data • 2004Fahy and Clarke’s CASS – • Inference Engine, historical context data, Context Knowledge base – you can assert, delete, modify, query the stored data(API) • 2004 CORTEX • based on sentient object model – sensor fusion to manage uncertainty of sensor data, CLIPS Inference Engine, historical context data • 2005 Example of Graphical Models • Context Modeling using UML : Sheng and Benatallah • 2007 Ejigu’sCoCA • 2008 Ejigu’s Enhanced CoCA
Upper ontology, domain-specific ontology Context aggregation/interpretation Broker federation Fundamental & new Ideas W3C, RDF available W3C, OWL available P2P Approach Centralized Approach Historical context data policy language to control context access Context Models Sentient object model Logic based context model: McCarthy and Buvac Graphical Models: Hendricksen’s ORM Markup scheme models: User Agent Profile (UAProf) Context Modeling using UML : Sheng and Benatallah Markup scheme model: W3C, Composite Capabilities/Preference Profile (CC/PP) Object-Oriented Model Attribute-Value Tuple Ontology-Model DAML+OIL 4-ary predicate Application & System Fahy and Clarke’s CASS Hofer’s Hydrogen Active Badge Location System Gu’s SOCAM Ejigu’s Enhanced CoCA Dey and Abowd’s Context Toolkit location-aware tour guide by Abowd CORTEX Ejigu’sCoCA Finkelstein’s IntelliZap Roman’s Gaia project location-aware tour guide by Sumi Chen’s CoBrA(Context Broker Architecture) Budzik and Hammond’s Watson Project Context-aware infrastructure: Munoz (hospital) Location-aware systems: Priyantha Koripaa’s Context Managing Framework location-aware tour guide by Cheverst Context Definition Dey and Abowd’scontext: “any information that can be used to characterize the situation of entities between a user and an application, including the user and the application the term ‘context-aware’ introduced by Schilt, Theimer Dey’scontext: user’s emotional state, focus of attention, location, orientation, date and time, objects and people in the user’s environment Context = Location Ryan’s context: user’s location, environment, identity and time the term ‘pervasive’ introduced by Weiser 1990 1991 1992 1994 1996 1997 1998 2000 2001 2002 2003 2004 2005 2007 2008 2010
Centralized Architecture Fundamental & new Ideas Non Centralized Architecture Semantic Technology Introduced Emphasis on Privacy & Sercutiry Context Models Upper Ontology + Domain Specific Ontology General Flexible Extensible Context Model = Ontology Model Non-Flexible Context Model Application & System Keywords: Generality Extensibility Flexibility Context System using More Flexible and Extensible Context Model Location-aware system General Context-Aware System Context Definition any information that can be used to characterize the situation of entities between a user and an application Location, Time, Environement, Identity, Emotionql Status, Orientation, Focus of Attention Location, Time, Environement, Identity Location 1990 1991 1992 1994 1996 1997 1998 2000 2001 2002 2003 2004 2005 2007 2008 2010
Conclusions • Limitations • None of them has done work on learning from historical context data • Only few systems(Gaia, CoBra, …) have security policies • Virtual and logical sensors are limited • Every system uses its own format to describe context and its communication mechanism • To Dos • 성찬이형과 Context Model 연구중-> 개발 된 Framework의 Rule Engine과 Context Model을 교체 • 앞으로의 연구 방향 • 실험 위주의 진행 • 실험 후 한계점 극복을 주목적으로 재 설정하고 연구진행 • Survey Paper • History of Context-aware Computing • Past, Present -> Future • Etc • Reading List