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How is the role of context awareness in mobile computing
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Context Awareness in Mobile Computing
The Revolutionary Impact of Pervasive Mobile Computing
Bob [email protected] Ilmu Komputer, Universitas Indonesia
SRITI 2011 Seminar Riset Tenologi Informasi
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SRITI 2011 - Seminar Riset Tenologi Informasi2
Pervasive – Ubiquitous – Mobile Computing
Low
High
Low HighLevel of mobility
Level of embeddedness
Ubiquitous Computing
MobileComputing
Traditional Business
Computing
PervasiveComputing
[1]
SRITI 2011 - Seminar Riset Tenologi Informasi
Mobile Computing: the Next Decade
Scenario 1: Lost Child
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SRITI 2011 - Seminar Riset Tenologi Informasi
Mobile Computing: the Next Decade
Scenario 2: Disaster Relief
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SRITI 2011 - Seminar Riset Tenologi Informasi
Mobile Computing: the Next Decade
Scenario 3: Cognitive Assistance
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SRITI 2011 - Seminar Riset Tenologi Informasi
Mobile Computing: the Next Decade
Scenario 4: Medical Consultation
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SRITI 2011 - Seminar Riset Tenologi Informasi
Reflecting on these Scenarios [3]
Embody a number of themes Rich sensors Crowd sourcing Near-real-time data consistency Opportunism Transient use of infrastructure User interaction
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SRITI 2011 - Seminar Riset Tenologi Informasi
Reducing Distraction
User attention is a precious resource
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The most successful mobile computing systems of the next decade will be those that are able to reduce or eliminate user interactions
SRITI 2011 - Seminar Riset Tenologi Informasi
User Interaction with Mobile Device
Mobile application autonomy can reduce user interaction.
Mobile application should place greater dependence on contextual information
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Context Definitions
Context defined variously as: An application/user’s environment or situation A combination of computing, user and physical features
Definition from Dey & Abowd [2]:“Context is any information that can be used to characterise the situation of an entity. An entity is a person, place or object that is considered relevant to the interaction between a user and an application, including the user and the application themselves.”
SRITI 2011 - Seminar Riset Tenologi Informasi11
Context Awareness
Context of computation may change
Context of computation may be (partially) captured by context information
Context information can be used to provide seamless computing provide relevant services to users
Needed: Information about requirements and current status of computations and their environments
SRITI 2011 - Seminar Riset Tenologi Informasi12
Context Information - Example
user location, devices, applications
user preferences and QoS requirements
application QoS requirements and status
device and network capabilities and their current status
relationships between context information
SRITI 2011 - Seminar Riset Tenologi Informasi
Context Awareness & Mobile Apps
Context-aware applications tend to be enhanced mobile applications for the following reasons: User context changes frequently subject to the user’s
mobility behavior The need for context-aware behavior is greater in a
mobile environment (user location, network resources, and device capabilities)
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SRITI 2011 - Seminar Riset Tenologi Informasi
Context-Aware Logic Space [4]
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SRITI 2011 - Seminar Riset Tenologi Informasi
Proximity selection
Proximity selection is primarily based on the user location context
Such context can be: resources and devices in the vicinity of the user places of interests closest to the user current position computational objects with which the mobile user is
currently interacting
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SRITI 2011 - Seminar Riset Tenologi Informasi
Context Modeling
Modeling context is a technique focuses on how to find and relate contextual information that better captures the observation of certain worlds of interest
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SRITI 2011 - Seminar Riset Tenologi Informasi
Context Modeling - Example
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Person(name)
Device(id)
Location(name)
has device
located at
Conceptual model (CML)
Logical model (relational model) HasDevice(Person, Device)
LocatedAt(Person, Location)
Maps to
SRITI 2011 - Seminar Riset Tenologi Informasi18
Person(name)
has device
Device(id)
Profile(code)
has profile
Base Station(nr)
Location Type(Name)
Network Strength
(nr)
Phone Number(nr)
Number Type(name)
Divert Status(name)
Allow Status(nr)
Disruption Level(name)
has nearest base station
has network strength
has location type
has phone number has number type
has disruption level
has allow status
has divert status
has divert type
Person(name)
has device
Device(id)
Profile(code)
has profile
Base Station(nr)
Location Type(Name)
Network Strength
(nr)
Phone Number(nr)
Number Type(name)
Divert Status(name)
Allow Status(nr)
Disruption Level(name)
has nearest base station
has network strength
has location type
has phone number has number type
has disruption level
has allow status
has divert status
has divert type
SRITI 2011 - Seminar Riset Tenologi Informasi
Context-Aware Application
Context acquisition
Context aggregation
Context consistency
Context discovery
Context query
Context adaptation
Context reasoning
Context quality indicators
Context integration
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A Context-aware application should have a set of characteristics related to context modeling, handling, adaptation:
SRITI 2011 - Seminar Riset Tenologi Informasi
Typical Architecture
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Context Manager
Context Gathering & Processing Layer
Middleware
Programming Toolkit
Context-Aware Applications
SensorSensorSensor
ContextModel
PreferenceManager
Context Manager
Context Gathering & Processing Layer
Middleware
Programming Toolkit
Context-Aware Applications
SensorSensorSensor
ContextModel
PreferenceManager
SRITI 2011 - Seminar Riset Tenologi Informasi
User Control of Context-Aware Mobile Apps
Context-aware mobile application may not always behave in the way users expected, due to Imperfect context information Incorrect user preferences Incorrect adaptation rules
Users may feel loss of control over their application.
The system must provide mechanisms to strike a suitable balance of control
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SRITI 2011 - Seminar Riset Tenologi Informasi
Balance of User Control
A continuum of user control versus application autonomy
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User controlApplication autonomy
A B C
SRITI 2011 - Seminar Riset Tenologi Informasi
Providing Suitable Balance of Control
Make users aware of reasons for application adaptation
User may be able to correct undesirable actions
Users may have varying levels of expertise
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SRITI 2011 - Seminar Riset Tenologi Informasi
Exposing the System’s view
Exposing system’s view of the context and its corresponding actions provides a sufficient understanding to correct inappropriate action (increases user control)
An appropriate modelling of context and preference is needed for revealing the information to the users
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Users
User Preferences
Adaptation Logic
Context Information
Context-aware System
Interactions
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Context & Preference
Manager
Context and preference change Information Filter
&Explanation Generator
Exposed application state information
User PreferenceDatabase
User Preference
User feedback
Informationrequest (scrutinize)
ContextDatabase
TracesDatabase
Programming Toolkit
De
sc
rip
tio
ns
Co
nte
xt
Gra
ph
Us
er
Mo
de
l
Semantic Manager
USER
Example Approach
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Context and Preference Manager
Semantic Manager
Context and Preference Proxy
ContextClient
Outside World
WebInterface
ContextWindows
User
contextchanges
contextchanges
preferencesand profile information
inquiry(scrutinizing)
revealedinformation
contextchanges
User interaction
Con
text
-Aw
are
App
licat
ion
context andpreference changes
context informationand preference
evaluation scores
SRITI 2011 - Seminar Riset Tenologi Informasi
Summary
User attention is a precious resource in mobile environment
Mobile application should reduce user interaction
Mobile application should place greater dependence on context
Need balance of user control due to imperfect context information
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SRITI 2011 - Seminar Riset Tenologi Informasi
References
[1] K. Lyytinen, Y. Yoo, Issues and Challenges in Ubiquitous Computing, CACM, Vol.4, No.12, 2002
[2] A. K. Dey and G. D. Abowd, Towards a better understanding of context and context-awareness. In CHI 2000 Workshop on the What, Who, Where,vWhen and How of Context-Awareness. The Hague, April 2000.
[3] M. Satyanarayanan, Mobile computing: the next decade, in MCS '10 Proceedings of the 1st ACM Workshop on Mobile Cloud Computing & Services: Social Networks and Beyond, 2010
[4] Christos B. Anagnostopoulos , Athanasios Tsounis , Stathes Hadjiefthymiades, Context Awareness in Mobile Computing Environments, Wireless Personal Communications: An International Journal, v.42 n.3, p.445-464, August 2007
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TERIMA KASIH