1. GeoBrowser Jonas Wolf MEng Individual Project Supervisor: Dr Stefan Rueger Second Marker: Ian Harries

2. 2/22 Motivation Newspapers Newspapers Television Television Internet Internet Mobile phone Mobile phone PDA PDA …

3. 3/22 Geo-Temporal News Browsing Where? Where? When? When? What? Who? What? Who?

4. 4/22 Geo-Temporal News Browsing Where? Where? When? When? What? Who? What? Who? Location (latitude, longitude) Time Interval (after, before) Text match

5. 5/22 Geo-Temporal News Browsing Where? Where? When? When? What? Who? What? Who? Location (latitude, longitude) Time Interval (t1 < t < t2) Text match t2nowt1t

6. 6/22 Geo-Temporal News Browsing Where? Where? When? When? What? Who? What? Who? Location (latitude, longitude) Time Interval (t1 < t < t2) Text match “elections” “Tony Blair”

7. 7/22 GeoBrowser Web-based geo-temporal news browsing tool Web-based geo-temporal news browsing tool Available from anywhere in the world Available from anywhere in the world browser and platform independent minimal client-side computation interactive

8. 8/22 System Design Server backend generates data Server backend generates data Client frontend provides user interface Client frontend provides user interface

9. 9/22 Demonstration Open browser Open browser Assume you are searching for news entries about the UK general elections this year. Assume you are searching for news entries about the UK general elections this year. Define a search filter of “election” Define a search filter of “election” Select the UK on the map Select the UK on the map Narrow down the time interval Narrow down the time interval Browse the results Browse the results

10. 10/22 Backend Java Web Application consisting of several servlets Java Web Application consisting of several servlets Running on Tomcat Running on Tomcat Multi-threaded Multi-threaded PostgreSQL database with PostGIS extensions PostgreSQL database with PostGIS extensions File System Database Web Server CommonServlet Web Service ImageThread DBThread Database

11. 11/22 Backend: CommonServlet Invoked after initialisation Generates data for client world map image reference map image events matches time histogram File System Database Web Server CommonServlet Web Service ImageThread DBThread

12. 12/22 Backend: DBThread Fetches data from DBMS Fetches data from DBMS Based on current selection of Based on current selection of time interval text query world region File System Database Web Server CommonServlet Web Service ImageThread DBThread Database

13. 13/22 Backend: ImageThread Generates map images for client based on current world region Generates map images for client based on current world region Uses a world atlas (several images at different resolutions) Uses a world atlas (several images at different resolutions) Data based on NASA Blue Marble Data based on NASA Blue Marble Maximum resolution 21600x10800 pixels Maximum resolution 21600x10800 pixels File System Database Web Server CommonServlet Web Service ImageThread DBThread Database

14. 14/22 Backend: Web Service Runs in Apache Axis Runs in Apache Axis Receives messages Receives messages communicates with CommonServlet communicates with CommonServlet Sends reply Sends reply File System Database Web Server CommonServlet Web Service ImageThread DBThread Database

15. 15/22 Client-server communication XML SOAP web service invocation XML SOAP web service invocation Event-driven Event-driven Client-initiated request-reply Client-initiated request-reply ready ready session ( updateState, getFullEvent ) session ( updateState, getFullEvent ) goodbye goodbye

16. 16/22 Frontend Java Applet running inside a web browser Java Applet running inside a web browser Renders map image in custom java panel Renders map image in custom java panel Multi-threaded for responsive GUI Multi-threaded for responsive GUI Java Virtual Machine Web Browser Java Applet MessageThread

17. 17/22 Frontend: MessageThread Communicates with server by invoking web service Communicates with server by invoking web service On creation, sends ready message On creation, sends ready message On request, updates state or requests additional information On request, updates state or requests additional information On shutdown, sends goodbye message On shutdown, sends goodbye message Java Virtual Machine Web Browser Java Applet MessageThread

18. 18/22 Usability Testing Usability Testing Usability Testing Ten users Ten users Asked to browse for information about general elections Asked to browse for information about general elections Questioned on visual presentation, map browsing, date selection, responsiveness and stability Questioned on visual presentation, map browsing, date selection, responsiveness and stability

19. 19/22 Usability Testing - Results Visual Presentation: well received Visual Presentation: well received Map Browsing: well received, mouse browsing preferred Map Browsing: well received, mouse browsing preferred Date Selection: complaints about lack of intuition in using sliders Date Selection: complaints about lack of intuition in using sliders Responsiveness: some complaints Responsiveness: some complaints Stability: found bug in zooming code Stability: found bug in zooming code

20. 20/22 Stress Testing 25,000 random events 25,000 random events Application launch time tested Application launch time tested Response times relatively fast, but Response times relatively fast, but very fast client-server connection single user

21. 21/22 Conclusions New, intuitive way of news browsing New, intuitive way of news browsing Available to anyone on the WWW Available to anyone on the WWW Work remains to be done Work remains to be done Scope for future research Scope for future research http://www.doc.ic.ac.uk/~jew01/project/ http://www.doc.ic.ac.uk/~jew01/project/

22. 22/22 Questions ?