Pervasive Computing

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Outline

Introduction Context Awareness Recent Research Future and Conclusion

Introduction (1)

The most profound technologies are those that disappear. They weave themselves into the fabric of everyday life until they are indistinguishable from it. --------Mark Weiser

Introduction (2)

普及計算 == 無間計算 時無間 -----anytime 空無間 -----anywhere 罪器無間 ---any devices 平等無間 ---any race 生死無間 ---service forever

Taxonomy of computer systems research problems in pervasive computing

Remote communicationFault toleranceHigh availabilityRemote information accessDistributed security

Mobile networkingMobile information accessAdaptive applicationsEnergy-aware systemsLocation sensitivity

Distributedsystems

Mobilecomputing

Pervasivecomputing

Smart spacesInvisibilityLocalized scalabilityContext-awareness

Federated communitiesVirtualizationStandardizationUneven condition Grid

computingGlobal

Smart Space

Four Additional Research Thrusts

Effective Use of Smart Spaces Invisibility Localized Scalability Masking Uneven Conditioning

Pervasive Computing ： Vision and ChallengesPersonal Communications, IEEE, Vol. 8 , Issue: 4 , Aug. 2001, p.10 - 17

Context-Awareness

What is context? Context is any information that can be

used to characterize 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 applications themselves.

Towards a Better Understanding of Context and Context-AwarenessGVU Technical Report GIT-GVU-99-22, College of Computing, Georgia Institute of Technology

Context-Awareness Context-aware applications look at the who’s,

where’s, when’s and what’s of entities and use this information to determine why the situation is occurring.

There are four primary types of context Location Identity Activity Time

Towards a Better Understanding of Context and Context-AwarenessGVU Technical Report GIT-GVU-99-22, College of Computing, Georgia Institute of Technology

The MIThril RealTime Context Engine

Issues of implementing a context-aware system

How is context represented internally? How is this information combined with system and

application state? Where is context stored? What are the relevant data structures and algorithms? How frequently does context information have to be

consulted? What is the overhead of taking context into account? What techniques can one use to keep this overhead low?

Issues of implementing a context-aware system What are the minimal services an environment needs

to provide to make context awareness feasible? What are reasonable fallback positions if an

environment does not provide such services? Is historical context useful? What are the relative merits of different location-

sensing technologies? Under what circumstances should one be used in

preference to another? Should location information be treated just like any

other context information, or should it be handled differently?

Recent Research

AHRI HawkTour

AHRI

Purpose: Design for people Background: Georgia Tech Broadband

Institute Residential Laboratory a three-story, 5040-square-foot home

that functions a living laboratory for interdisciplinary

design, development and evaluation.

AHRI Gesture Pendant

Simplified home control

System Architecture

Video

Locations

Camera 1(Fixed)

Camera 2(Fixed)

ColorTracking

ColorTracking

MotionTracking

MotionTracking

Calibrated

Video

Camera 3(PTZ)

Camera 4(PTZ)

ColorTracking

BeamFormer

FaceTracking

AuditoryLocalization

FaceTracking

Video

Video

More Sensors More Sensors

RoomManager

FaceRecog.

Illinois Institute of Technology The application would run on PDAs or Tablet P

Cs Provide users with general campus information

while guiding the user around the campus Maintain continually awareness of the user’s c

urrent location and intent, thereby adapting the tour to the user’s own personal preferences and context.

Hawk Tour—A Context-aware Visitor Guide

Specific of Hawk Tour

Hawk Tour uses the Ekahau Positioning Engine which makes use of the received signal stren

gths from WiFi access points to determine positions of the user

Use 「 Scarlet 」 to collect and provide context information

Scarlet—A framework for context-aware computing Separate infrastructure functionality with

application-specific functionality

Non Functional Requirements Scalability Modularity Cross platform Security Extensibility Ability to Evolve Quality of Service Fault Tolerance Mobility User Friendly Interface

Functional Requirements Context collection Context

Storage/Management Context

Subscription/Delivery Context

Analysis/Composition Ability

Separation of Application and Infrastructure

The Scarlet System

Future and Conclusion

我們的未來不是夢 ?

---The End--Thank you for your listening!