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UbiCom Book Slides
1Ubiquitous computing: smart devices,environments and interaction
Chapter 7Context-Aware Systems
(Part A: Contexts & the Context-Aware Lifecycle)
Stefan Poslad
http://www.eecs.qmul.ac.uk/people/stefan/ubicom
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Chapter 7: Overview
Chapter 7 focuses on:
Internal system properties: context-awareness
External interaction with any type of environment
Focussing more on physical environment
A lesser extent focussing on ICT environment
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Related Chapter Links
Context-awareness of human environment (iHCI) andperson-awareness and user context acquisition (Chapter 5)
Environment context acquisition: sensors (Chapter 6)
Environment context control: controllers (Chapter 6)
Event-based system models for context-awareness(Chapter 3)
Goal-based models & sequential environment models
(Chapter 8)
Content adaptation for mobile terminals (Chapter 4)
UI techniques adapted for use in small and large displays
discussed (Chapter 5)
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Chapter 7: Overview
The slides for this chapter are also expanded and split into
several parts in the full pack
Part A: Contexts & the Context-Aware Lifecycle
Part B: Context Adaptation Design
Part C: Spatial Awareness 1
Part C: Spatial Awareness 2
Part E: Mobile Awareness
Part F: Temporal Awareness & Composite Context
Awareness
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Lecture Outline
Types of Context and Context Properties
Context Aware Life Cycle
Context Adaptation
Spatial-Awareness
Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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6Ubiquitous computing: smart devices, environments and interaction
Smart (Physical) Environments
Physical
Environment
Devices Context-aware
Physical
Environment
Context Types
CPI
Structure
Human ICT
Location-
aware
GIS
Location
Sensoror Tag
Device
Display
Content
adaptation
Mobile
aware
Personalisation
Time-
aware
Self-aware
iHCIHomogeneous
SingleAttribute
MultipleAttribute
Life-Cycle
Single Multiple
Heterogeneous
Control
Sense
Adapt
Active
Passive
Operation
Acquire
User
Acquire
Env.
Manage
Present
Process
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Context Aware System versus Sensor-
based System
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Contexts
A context represents the state or situation in theenvironment of a system that affects that systems
(application specific) behaviour
There are many definitions of context
There are several dimensions or properties tocharacterise contexts
There are many definitions of how to make systems
aware of changes in their context: context awareness
Context-awareness is considered to be one of thefundamental properties of UbiComp systems and is a
key property of smart environments.
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Defining Contexts: Concrete
In terms of membership of some set of contexts Location, identities of nearby people, objects and changes
to those objects
Applications
External environment: physical, human, virtual Awareness of internal (self) context may also be useful
What, who, where, when, how it is accessed and why,
context is useful (Morse et al. (2000)
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Context Types: By Application
We can classify context-awareness in terms of types ofapplications?
Mobility context-aware
Location aware
Time aware
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Lecture Outline
Types of Context & Context Properties
Context Aware Life Cycle
Context Adaptation
Spatial-Awareness Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness Composite Context Awareness
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Life-cycle for Context Awareness
Capture Physical Context Capture User Context
Context Processing
Adapt to Context
Manage contexts
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13Ubiquitous computing: smart devices, environments and interaction
Configuration
Actuators
Sensors
Environment
Abstraction
Display
User Tasks
Events
UserContext
Context
Store
Store /Retrieve
Annotated Content
AdaptedContext
Control
Adaptation
User EnvContextMediationEnv Context
Composition
Context Processing
& Adptation
Environment (Env)Context Creation
Non-adaptedContext
Access
Control
Annot-ation
Context Management
Application
User ContextCreation
ContextControl
Access
Context Filter
Policies
Context
Discovery
Discovery
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User Context Creation
Acquisition of user context: this can be derived from usersapplication tasks
Policy creation: created from users tasks to determine howa user context is mediated by environment contexts
Encapsulation and abstraction: of the user context
Sharing the user context so that it can be distributed and
accessed.
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Environment Context Creation / Capture
Acquisition:
Encapsulation:
Abstraction:
Filtering:
Sharing:
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Context Processing
N.B Context acquisition may involve some context pre-processing, here the focus is on context post-processing.
Context post-processing enables:
Context-composition:
Context Mediation: Context Adaptation:
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Context Composition: Motivation
Context composition may also be driven by the need to: Improve acquisition accuracy for the context
Improve filtering and adaptation of content
Composite contexts are in inherent an application
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Context Composition: Challenges
Handling heterogeneity of representation Handling heterogeneity of meaning
Mediating and coordinating context aggregation
Ordering the adaptation to individual contexts
Different weightings for combining contexts
Handling uncertainty in combining contexts
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Context Composition, Heterogeneous
Contexts & Interoperability
Context-aware systems may depend on & combine: multiple representations for a single context
.
multiple representations of multiple contexts
Multiple representations determined independently by
different applications & users
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Context Composition, Heterogeneous
Contexts & Interoperability
Determination of a proposed joint context for meetingcan be complex
Challenge here: to harmonize or standardize annotation
so that they would be consistent used by all users.
Security, e.g., access control could be useful in certain
applications to protect privacy or to limit access,
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Context Management
Discovery: directory services enable context sources,stores and users to be registered and discovered.
Storage: of context data into some data resource, may
include
Sharing of environment and goal contexts
Access control:
.
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness
Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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Context Adaptation: Passive vs Active
Passive context adaptation system Context is presented to users
Context-based tagging (chapter 6)
System is not active in terms of adapting
Active context-adaptation system Adaptation to context performed by the UbiCom system, not human
users.
Hybrid context adaptive system
Human user guides or corrects the automatic adaptation
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Context Adaptation Models
Event-based Models (Chapter 3) Context-awareness links context producer to a context-
consumer or context-adapter
EDA is also similar to a Reactive intelligent system
See Chapter 8
How do we limit the types of interest?
Goal-based Models
Use a (planned) application or user goal to limit the set of
current contexts which are useful Relation of current context to goal context is
fundamental
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Context-aware Application: Location
(context) awareness
Goal
context
Current
context Context
Path
Constraints
Travel to the destination
location
Current location
Planned path from the current
to destination location
Not to deviate too far from theanticipated or planned position
context;
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Context-aware Application: Location
(context) awareness
26Ubiquitous computing: smart devices, environments and interaction
Start Context
Move Forward
Context Deviation
Planned Current Context
Move To SideRe-plan & Move forward
Goal Context Planned Current Context
start
Context Deviation
Move To Side
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Context Aware Design Issues
Context Representation Use of Current versus Past Contexts
Context Determination
Static versus Dynamic CA
Active versus Passive Context Adaptation (done)
Heterogeneous Contexts & Interoperability
Context Composition
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Context Representations
What type of data structures should be used to modelcontexts?
Key-Value pairs
Hierarchies / Markup Schemes, e.g., XML
Graphs Object Oriented (o-o)
Logic Based: support reasoning about context
Strong Ontology
Which of these is best? Why?
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Use of Current Context vs. use of
Context History
Simplest type of context-aware system Uses the current context, the current state, episodic, environment
Operates in an environment that is fully observed and deterministic
But context history can also be used
See Chapter 8 for more in-depth treatment of environments
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CA Design issues: Context
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CA Design issues: Context
Determination
Context determination: acquisition, accuracy particularly ofuser context can be complex
Active versus passive context acquisition
Single shot (static) versus dynamic acquisition
Heterogeneous context representation (syntax) andsemantics, interoperability
Context distribution: Local context producer but remote
context consumer
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User Context Determination
4 approaches
Combine several low-level sensor inputs to better infer user
context,
Can Query user profile or model: abstraction thatcharacterises the user, preferences the user expresses,
Ask users to define their own context.
Observing user interaction
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Static versus Dynamic CA
Static environment context
Dynamic environment context:
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Context Adaptation Benefits
Many useful Applications:
Reduces information overload on users
Lessen cognitive load on users
Filter information to fit a mobile device's limited and
physically moving display,
Disabled people
Improve Regulation & Control
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Context-awareness: Challenges
1. User Contexts may be incorrectly, incompletely, impreciselydetermined or predicted, ambiguous
2. Environment Contexts may be incorrectly, incompletely, imprecisely
defined, determined or predicted.
3. Contexts may exhibits a range of spatial-temporal characteristics
4. Contexts may have alternative representations 5.Contexts may be distributed and partitioned, composed of multiple
parts that are highly interrelated
6. Contexts may generate data huge volumes
7. Context sources and local processes often need to embedded in a
low resource infrastructure
8. Context use can reduce the privacy of humans
9. Awareness of context shifts can distract users
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness
Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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Spatial-Awareness Overview
1. Trigger spatial-aware services2. Sense / determine current Location
3. Determine the spatial context
4. Service adaptation: adapt spatial information
view w.r.t. to location
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Spatial-Aware Applications
Applications which trigger use of spatial aware Navigation,e.g., I'm lost, where is nearest Metro station?
Notification of context change: e.g. traffic queue ahead,
change route..
Querying location context, e.g. What speed limit on this road?
Personal Emergency: e.g. medical and Roadside Emergency Service Operations: e.g., Are flammables
nearby?
Enterprise Asset Tracking: e.g. Where is water supply?
Public Asset Trackinge.g. where is the train now? Personal Asset Trackinge.g. I lost my PDA, where is it now?
Location / time based offers,e.g. Free mobile phone calls
while you are in location X
Location & time synchronisation: e.g., ImaHima users37Ubiquitous computing: smart devices, environments and interaction
L ti A S ti l A
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Location-Aware vs Spatial Aware vs
Composite Spatial Aware
Triggering Awareness of a locationa point in 3D space
Awareness of a location in relation to another location
Awareness of a location in relating to its surrounding 2D
space
Composite spatial awareness
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Location Determination Methods
Several common Methods Proximity Analysis
Triangulation
Time Difference of Arrival(TDOA), Multi-lateration
Trilateration
Received Signal Strength(RSS)
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Location Determination :
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Location Determination :
Triangulation
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If distance AB, angles at A and B are known
then X and Y can be determined using basic
trigonometry
Sin A = Y / a
Sin B = Y / b
Y = a * Sin A = b * Sin B
Cos A = X / aX = a * Cos A = ABb * Cos B
O
A B
Yab
X
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Location determination: TDOA
Time Difference of Arrival(TDOA), Multilateration TOA measurement of time signal sent vs. time received:
distance d = time t * signal propagation speed s.
N.B. Assumes accurate clock synchronisation, sender knows time
of transmission
TDOAor measurement at 2 or more receivers (or sent from
2 or more senders)
use to estimate the difference in distances between the 2.
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Location Determination: Trilateration
Trilateration: uses absolute measurements of time-of-arrival from three or more sites
Trilateration is a method of determining the relativepositions of objects using the geometry of triangles in asimilar fashion as triangulation.
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L ti d t i ti T il t ti
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Location determination: Trilateration
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3 Equations to determine location of point O
w.r.t. known locations A,B, and C on a 2D plane
RA2 = X2+Y2
RB2 = (X-(AO+OB))2+Y2
RC2 = (X-AO)2+(Y-OC)2
Use substitution to get X and Y
X = (RA2- RB
2 + (AO+OB)2) / 2 (AO+OB)
Y = (RA2- RC2 +AO2+OC2) / 2OC)AOX / OC
OA
C
B
RC
RBRA
X
Y
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Location Determination: RSS
Received Signal Strength(RSS)Estimate the RF signal strength at a receiver
Knowing the transmission signal strength
Knowing the attenuation of the signal as a function of
distance and signal transmission strength, e.g., 1/r2
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Location Determination: Range
IR / BlueTooth: ?
RFID systems: ?
WLAN: ?
GPS: ?
GSM: ?
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Location Determination: Uncertainty
Distance & timing measurements has some uncertainty inpractice:
variable attenuation (due to moisture in air etc),
multi-path effects,
reflections,
spot interference,
knowing the time of transmission accurately etc (see also Chapter 11)
How can we correct for this uncertainty? We can measure signal w.r.t to multiple transmitters to correct for
this variability
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Location Determination: Handling
Inaccuracy & Uncertainty
Handling the lack of accuracy, uncertainty in the location
Accuracy requirements for some applications can berelaxed
Could use orientation or a priori knowledge of geo-attributes to help determine the location, .
Can use hybrid systems or assisted systems that combinestrengths and minimise weaknesses of several systems.
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Location & Other Spatial Abstractions
Location coordinate in itself is often not so useful, it is too
low-level
It is the Spatial context for a location that is useful and
gives it the location meaning. E.g.,
Forward-tracking: relation of the current coordination to anend coordination / future goal e.g.,
Backward tracking: relation of current location coordination
to start coordination, to past routes, to past goals
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G
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Location Awareness: Geographical
Information System (GIS) Need spatial services to determine the spatial context
This is a GIS service
A GIS service needs to do more answer spatial queries, italso needs to be:
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L ti A G hi l
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Location Awareness: Geographical
Information System (GIS)A GIS system supports services to support:
Spatial context representations
Spatial context capture
Spatial annotation: bind context to geometric object or view
Coordinate transformation
Spatial data storage Spatial analysis including queries
Spatial data output & cartography
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Geospatial Information System (GIS)
A service, such as a Geospatial Information System (GIS)service, is needed to answer spatial queries
E.g., Is there a type of service X within 1 km of here?.
GIS services represent real world objects
such as roads, land use, elevation with digitised spatial data.
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GIS: What the Data Represents
Geospatial data consists of multiple parts: Geometrical object
e.g., point, line, polygon etc
Geo-attributes that form the spatial context
e.g., types of feature, and associated attributes, e.g
Annotations of geometrical object
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GIS: Data Representation
GIS represents real world objects (roads, land use,elevation) with digitised spatial data
Real world spatial objects can be discrete objects(house)
continuousfields (rain fall, elevation)
Digitised GIS data consists of two parts Geometrical objects Spatial context / Geo-attributes
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GIS: Geometric Data Capture
There are a variety of methods used to capture Geo-context
Digitizer e.g.,
Scanner e.g.,.
Direct entry of surveyed or sensed data E.g.,, Photo interpretation of aerial photographs.
E.g.,
Can configure relative location accuracy vs. absolute
accuracy & level of accuracy.
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GIS: Spatial Context Capture
Geocoding: derive location from spatial context
Reverse geocoding: derive spatial context from location
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GIS Data Capture: Processing
Geo Data after capture usually requires editing
Vector data must be made "topologically correct" before itcan be used for some advanced analysis. Projections
Adjacency
To remove errors E.g.,
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GIS data coordinate Transformation
100+ different coordinate systems exist for positions
Likely that measured location co-ordinates & geospatialobject coordinates in GIS will be different
-> Need transformations
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GIS Data Storage & Retrieval ';
Many DBs with spatial extensions use GIS data structuresthat are based on the Open GIS Consortium (OGC)Geographical Markup Language (GML) standards
Spatial databases are optimised?
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GIS: Spatial Queries
Example query, How far, as the crow flies, from QueenMary to Mile End Tube?
SELECT (orig.buildinglocdest. buildinglloc)*37.5 AS "Distance (kms)"
FROM buildingl orig, buildingl dest
WHERE orig. buildinglname = Queens Building'
AND dest.buildingname = MileEnd Tube Station
A spatial query involves determining which indexed region a spatial object of interest is in where a region
bounds a set of spatial objects
then locating a specific object within that selected region,
e.g., determining the distance from Queen Mary (Object D) to Mile-
End Tube station (Object A)
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GIS: Spatial Queries
60Ubiquitous computing: smart devices, environments and interaction
A
B
C
D
E
XY
Spatial Adaptation GIS Data o tp t
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Spatial Adaptation: GIS Data output
& Cartography Some main uses of spatial-adaptation:
????
Cartography is the design and production of maps, orvisual representations of spatial data.
The vast majority of modern cartography is done with thehelp of computers, usually using a GIS. Most GIS softwaregives the user substantial control over the appearance ofthe data
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GIS Data Output & Cartography
Cartographic work serves two major functions: It produces maps and other graphics,
To allow the map to be annotated with symbols and text forthe information of interest,
Web Map Servers facilitate the exchange of generatedmaps information via Web Services,
e.g., ???
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness
Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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Context awareness: Indoor Call
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Context awareness: Indoor Call
Routing For Mobile Users
Active Badge Location System of Want et al. begun in 1989 Location awareness users to route calls through to their
nearest fixed line phone indoors
Readers detect signals from wearable active badges
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Mobile User (ICT) Context awareness:
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Mobile User (ICT) Context awareness:
WAN Call Routing For Mobile Users
Basic mobile phone location determination . Determine which mobile phone transmitter, its area of
operation (its cell), phone is nearest to.
Phone users registered in HLR
When users pass between areas, a cell notifies its VLR When a call is made by user B to user A, the call first
queries the VLR
If A not there, call is made to As HLR
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Location Determination in A Mobile
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Phone Network
66Ubiquitous computing: smart devices, environments and interaction
MSC
MSC
Core PacketSwitched
Network
HomeLocationRegister
HLR
Mobile
Switching
Center
VLR
VisitorLocationRegister
Base station / Cell
User Ahas moved
User B
Group of Cells
User A
User C
User B
calls User
A
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness
Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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Content Adaptation for Mobile
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Content Adaptation for Mobile
Terminals
Content adaptation to two main types of ICT are consideredhere:
Adaption to the terminal
Adaption to the network connecting the terminal
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Content Adaptation for Mobile
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p
Terminals
UI facilitates presenting and entering information for humanuse
Universal content access entails content access via a
proliferation of interactive devices with diverse capabilities.
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UI C t t R t ti
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UI Context Representation
The UI context can be defined in a UI device profile. There are several different specifications for representing
the UI profile.
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C t t Ad t ti
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Content Adaptation
Needed to adapt content for display Much content designed for decimetre sized screens:
But what if displayed on small displays? e..g, mobile phone
But what if displayed on large screens? e.g., projectors,
Need Content adaptation this involves: Transformation of the created content representation to a differentone used in the access device,
Adaptation of the (multimodal) interaction
Adaptation to use a particular device display convention
Adaptation of the content itself.
See also the range of UI techniques adapted for use in
small and large displays (Chapter 5)
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Content Adaptation Net ork A are
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Content Adaptation: Network-Aware
A service that is aware of the characteristics of the physicalnetwork is called underlay-networkaware (Chapter 11)
Enhancements are needed to TCP/IP network design to
support more flexible context-aware QoS delivery.
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness Composite Context Awareness
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Temporal Awareness: Time
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Temporal Awareness: Time
Time may be modelled as a period
Time may be modelled as an instant,
Time can be modelled as a linear sequence
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Time Awareness: Scheduling
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Time Awareness: Scheduling
Task scheduling is simplest when
Simple scheduling can involve deriving a personalised
schedule that it a subset of another schedule known apriori,
e.g., .
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Time Awareness: Scheduling
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Simple job scheduling algorithm is to partial order n tasks in a graph and to search it to
find a path
78Ubiquitous computing: smart devices, environments and interaction
0
1T2 2T2 3T2 4T2
Task 1
Working
Task 2: Break
to eat & drink
Known periods but
flexible execution &
deadline
Known
execution
time Known
deadline
Task 3
Traveling
4T
Task 4
Leisure
T1 2T1 3T1
T1 2T1 3T1
1T41T3 5T 6T 7T3T2T1T 1T1
5T2
1T2
1T3 2T3
2T41T4
1T11T
2
1T32T2
2T1
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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Composite Context Awareness for
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Mobile Users
Mobility context awareness is a good example of compositecontext adaptation.
Spatial awareness is used to adapt activities with respect to
their locality.
Information retrieval from remote sources can bepersonalised to users preferences.
ICT context-awareness is useful for mobile users so that it
adapts remotely accessed content so that it fits better the
characteristics of mobile access devices and better fits the
bandwidth available in the local wireless access loop.
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Context Composition Example: CRUMPETProject System
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Project System
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Persona interestsl
Users
Terminals
Service Providers
Terminal
profile
Network
Link description Service
capabilities
Userpreferences
User
position
Interaction
& Service
Facilitation
Mediator
GPS
e.g., maps, routes, sight and
restaurant recommendations
CRUMPET P j t S t
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CRUMPET Project System
CRUMPET, Creation of User-friendly Mobileservices PErsonalised for Tourism, EU FP5 Project
system is an example of a composite context
adaptation application.
In this system, tourism information services suchas maps, routes and sight recommendations can
be adapted to a spatial context that pertains to the
current location, the personal context of a service
uses, the network context and the terminal context,
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The CRUMPE T System
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My IP address
and port are...
Ok, here are your nearby
points of interests.
Components:
Map of the world
Diagnostics information
Client status (Agent and network status)
Points of interests
Map components:
Map of thenearby world
Start/Edit tour
Status bar with
proactive bulb
Here is my
new location.
CRUMPET Multi-Agent System Architecture
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Ubiquitous computing: smart devices,
environments and interaction
End user
Services
User
agent
MediatorAgents
Service
agents
Service
agents
Network
agents
Client /Terminal
Agent
Context-aware
Middleware
NetworkNetwork
agents
Fixed Network Services
Access
Node
Mobile
Device
wireless
Web Browser
GPS
Contet AdaptationService Agent Location agent
User modeling agent
Composite Context Awareness:
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CRUMPET System
Particular ordering of context-aware adaptation follows.
Users access terminal profile of memory & display
capabilities is exchanged with system during session start
Localisation is for example used twice
Current position of a user can be used to constrain a user'srequest and to further filter the relevant information.
Unless the relevant location is specified explicitly, user gets
information relevant for his or her current spatial context.
users movements within region can indicate their interests. E.g., a user visits a number of old churches, then he or she is
probably interested in churches and perhaps also other historic
buildings in this town, like an old city hall.
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Composite Context Awareness:
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Composite Context Awareness:
CRUMPET System Users generate a lot of potential events of interest as they move.
These can be exploited for user modelling & to detect & anticipate
relevant user interests.
Hence, the combined location and personal model context can be
used to such as get me a map of things of interest at a location.
This is an example of environment context composition in which onetype of context (location) may be used to determine another type of
context (personal preferences) based upon a user context policy.
Finally, the network profile based upon monitoring the performance
of the local mobile terminal to access node, the content, e.g., a
personalised, location-aware map is adapted to the terminal andnetwork profile respectively.
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Composite Context Awareness:
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Composite Context Awareness:
Note the context composition challenges (Revision from
Chapter 5 slide set a )
Handling heterogeneity of representation
Handling heterogeneity of meaning
Mediating and coordinating context aggregation Ordering the adaptation to individual contexts
Different weightings for combining contexts
Handling uncertainty in combining contexts
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CRUMPET System Screenshots
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y
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CRUMPET System: Fat-client
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Dillo
CRUMPET Services
Fixed Network
Service Provider
Service Provider
Service Provider
Wireless Station
CCA
MA
UMA
SCA
MAPA
CA
DCA CASACA
GSA
TA
SA
Satellite
MA
WMTP - full control over wireless link
Agent processing -
complete control over GSM
triangulation, GPS and browser
Wireless Station
y
Architecture
This deployment architecture has a larger client-side
Footprint and is suitable for deploying in
high end PDAs and PCs
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CRUMPET System: Thin-Client
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y
Architecture
This deployment architecture has a very small client-side footprint and is
suitable for deploying in low end PDAs and suitably equipped mobile 'phones
Fixed Network
HTTP
Service Provider
Service Provider
Service Provider
Wireless Station
CCA
MA
UMA
SCA
MAPA
CA
DCA CASA
GSA
TA
SA
Satellite
HTTP - no control over link
JAVA process -
very little control
over GPS and browser
ExplorerCE
CRUMPET Services
Wireless Station
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Lecture Outline
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Lecture Outline
Types of Context and Context Properties Context Aware Life Cycle
Context Adaptation
Spatial-Awareness Mobile User Context Awareness: Call Routing
Content Adaptation for Mobile Terminals
Temporal awareness
Composite Context Awareness
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Revision
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Revision
For each chapter
See book web-site for chapter summaries, references,
resources etc.
Identify new terms & concepts
Apply new terms and concepts: define, use in old andnew situations & problems
Debate problems, challenges and solutions
See Chapter exercises on web-site
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Exercises: Define New Concepts
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p
Context-awareness
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Exercise: Applying New Concepts
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