UrbanWeb is a novel Web-based context-aware hypermedia plat-form. It provides essential mechanisms for mobile social comput-ing applications: the framework implements context as an exten-sion to Web 2.0 tagging and provides developers with an easy to use platform for mobile context-aware applications. Services can be statically or dynamically defined in the user’s context, data can be pre-cached for data intensive mobile applications, and shared state supports synchronization between running applications such as games. The paper discusses how UrbanWeb acquires cues about the user’s context from sensors in mobile phones, ranging from GPS data, to 2D barcodes, and manual entry of context in-formation, as well as how to utilize this context in applications. The experiences show that the UrbanWeb platform efficiently supports a rich variety of urban computing applications in differ-ent scales of user populations.

1. AARHUS
UNIVERSITY
UrbanWeb: A Platform for Mobile
Context-aware Social Computing
Frank Allan Hansen & Kaj Grønbæk
Center for Interactive Spaces (http://www.interactivespaces.net)
Department of Computer Science
Aarhus University
{fah,kgronbak}@cs.au.dk
21st ACM conference on hyptertext and hypermedia (HT2010)
Toronto, Canada, June 13-16, 2010
PRESENTATION
Friday, June 18, 2010

2. AARHUS Allan Hansen 2
UNIVERSITY fah@cs.au.dk
Talk Overview
›Urban Computing
› Examples & requirements
›The UrbanWeb platform
› A light-weight approach to mobile, urban computing
›UrbanWeb Examples
› Mobile social services
› Static & dynamic services
› Unobtrusive data handling
› Sessions & synchronization
›Summary & Conclusion
Friday, June 18, 2010

3. AARHUS
UNIVERSITY
Urban Computing
Friday, June 18, 2010

4. AARHUS Allan Hansen 4
UNIVERSITY fah@cs.au.dk
Mobile Urban Computing Examples
› Linking content to physical places
› Ubiquitous hypermedia support for urban environments.
› E.g. BBC “Coast” (Active print) [17], Semapedia [23].
› Creating and sharing content
› Social Media Application.
› E.g. Micro-blog [9], Yahoo ZoneTag [1].
› Mobile and context-aware learning
› Combines the two above.
› Support for pre-, during-, and after-processing.
› E.g. ContextBlogger [5], HyconExplorer [10].
› Games and experience applications
› Time and location dependent.
› Often multi-user.
› E.g. HP Labs Mediascape [25], Locating drama [19].
[* References included in the paper]
Friday, June 18, 2010

5. AARHUS Allan Hansen 5
UNIVERSITY fah@cs.au.dk
Mobile Urban Computing Functionalities
› Context tagging
› A mechanism for specifying the context for content.
› “Ubiquitous link anchors” that support anchoring of digital content in
the physical environment.
› Context-aware services
› Making it easy for developers to create services that utilize context-
awareness and integrate with the urban environment.
› Authoring and resource sharing
› creating and sharing material is of great importance to many types of
urban computing applications,
› e.g., both social media and mobile learning applications.
› Shared application state
› Multi-player pervasive games require game state to be
communicated between participants in real-time.
Friday, June 18, 2010

6. AARHUS
UNIVERSITY
The UrbanWeb Platform
Friday, June 18, 2010

7. AARHUS Allan Hansen 7
UNIVERSITY fah@cs.au.dk
UrbanWeb
›UrbanWeb developed
2007-2010
›Lightweight Web-based
platform for urban
computing.
› Context and services.
›Web-based: “One-Web”
› One service - multiple interfaces
› Html-based (HTML5)
› Widget-based (E.g. Nokia Web Runtime
(WRT))
› Hybrid applications (E.g. PhoneGap, ...)
› Native applications (E.g. Java, Objective C, ...)
Friday, June 18, 2010

8. AARHUS Allan Hansen 8
UNIVERSITY fah@cs.au.dk
Context modeling: tagging as primitive
Friday, June 18, 2010

9. AARHUS Allan Hansen 9
UNIVERSITY fah@cs.au.dk
Context modeling: tagging as primitive
UrbanWeb_Property
*
1 * 1
UrbanWeb_Reference UrbanWeb_BaseObject UrbanWeb_Composite
›UrbanWeb_BaseObject
› Modeled by (name, type, value)-properties
› Internal and external
› Introspection provides a common programming interface
› UrbanWeb_Properties are treated as regular class
properties
Friday, June 18, 2010

10. AARHUS Allan Hansen 10
UNIVERSITY fah@cs.au.dk
Context matching
Friday, June 18, 2010

11. AARHUS
UNIVERSITY
UrbanWeb
Services and Applications
Friday, June 18, 2010

12. AARHUS Allan Hansen 12
UNIVERSITY fah@cs.au.dk
Services - static and dynamic
› TagBlogger
› 2008-2009 Aarhus Festival
› Goal: letting users
› Access (official) location sensitive
information about the festival in the city
› Create their own digital overlay on the
city
› Share their materials with other festival
participants in the city
› Services:
› Location-based information service,
› mobile blogs,
› polls,
› and an RSS-based festival program
› Anchored on TAGs and GPS coordinates
Friday, June 18, 2010

13. AARHUS Allan Hansen 12
UNIVERSITY fah@cs.au.dk
Services - static and dynamic
› TagBlogger
› 2008-2009 Aarhus Festival
› Goal: letting users
› Access (official) location sensitive
information about the festival in the city
› Create their own digital overlay on the
city
› Share their materials with other festival
participants in the city
› Services:
› Location-based information service,
› mobile blogs,
› polls,
› and an RSS-based festival program
› Anchored on TAGs and GPS coordinates
Friday, June 18, 2010

14. AARHUS Allan Hansen
UNIVERSITY fah@cs.au.dk
Authoring, resource sharing & sessions
› HasleInteractive 2009
› Mobile Urban Drama
› Interactive narrative
› Mobile learning
› Math and Biology
› Unobtrusive data handling
› Session and group handling
Friday, June 18, 2010

15. AARHUS Allan Hansen 14
UNIVERSITY fah@cs.au.dk
HasleInteractive - content and sessions
Friday, June 18, 2010

16. AARHUS Allan Hansen 15
UNIVERSITY fah@cs.au.dk
Sessions - pre, during, and after process
›Arla “Økofonen”, 2010
›Interactive narrative.
› Organic milk.
› Story about the cows.
›Session support;
› pre, during, and after process
›Before: at the morning
table.
›During: at the farms.
›After: at the computer
Friday, June 18, 2010

17. AARHUS Allan Hansen 15
UNIVERSITY fah@cs.au.dk
Sessions - pre, during, and after process
›Arla “Økofonen”, 2010
›Interactive narrative.
› Organic milk.
› Story about the cows.
›Session support;
› pre, during, and after process
›Before: at the morning
table.
›During: at the farms.
›After: at the computer
Friday, June 18, 2010

18. AARHUS Allan Hansen 15
UNIVERSITY fah@cs.au.dk
Sessions - pre, during, and after process
›Arla “Økofonen”, 2010
›Interactive narrative.
› Organic milk.
› Story about the cows.
›Session support;
› pre, during, and after process
›Before: at the morning
table.
›During: at the farms.
›After: at the computer
Friday, June 18, 2010

19. AARHUS Allan Hansen 16
UNIVERSITY fah@cs.au.dk
Session recording and transfer
Friday, June 18, 2010

20. AARHUS Allan Hansen 17
UNIVERSITY fah@cs.au.dk
Summary and Conclusion
› UrbanWeb: light-weight hypermedia support for
urban computing applications
› Model is based on simple tagging paradigm
› built-in support for context matching
› Platform supports common requirements
› Context model, context-aware service, In-situ authoring and
resource sharing, and shared application state.
› One-web approach
› One service - multiple interfaces.
› Different urban computing applications
› Social services.
› Mobile learning.
› Experience applications.
Friday, June 18, 2010

21. AARHUS
UNIVERSITY
Thank you for listening!
Any questions?
Frank Allan Hansen & Kaj Grønbæk
Center for Interactive Spaces (http://www.interactivespaces.net)
Department of Computer Science
Aarhus University
{fah,kgronbak}@cs.au.dk
This work is supported by Center for Interactive Spaces and the Alexandra Institute. The UrbanWeb
project is funded by the Danish Agency for Science, Technology and Innovation, project 274-07-0218.
21st ACM conference on hyptertext and hypermedia (HT2010)
Toronto, Canada, June 13-16, 2010
Friday, June 18, 2010