Collective Sensing

Helena Merschdorf, Matthias Stängel, Benjamin Lieberknecht, Christopher Haupt

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Explore the tweetsStraightforward, simple,

self-explaining

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The engine

Client• Javascript• Gmaps API

Server• PHP

Database• Postgres

① ②

④ ③

Build query Create GeoJSON

Feature Collection

Run query Send result

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GeoJSON

• Geospatial JavaScript Object Notation

• Lightweight data-interchange format

• Geometry Objects• Points (MultiPoint)• Lines (MultiLines)• Polygon (MultiPolygon)• Geometry Collection• Feature Collection

{ "type":"FeatureCollection", "features":[ { "type":"Feature", "geometry":{ "type":"Point", "coordinates":[ 13.41739655, 52.51674317 ] }, "properties":{ "txt":"Christmas Christmas HoHoHo... ", "source":"Android", "ulang":"en", "tweettime_wtz":"2012-12-01 12:26:06+01", "userid":"743034529" } } ]}

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Constraints

• Number of points visible at once• Are cluster the solution?• Javascript visualization limits• Java?

• Time of the query and processing• Time limits to execute a script with PHP

• Lack of memory for processing• Memory for scripts• Memory for visualization

• Google maps API

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Outlook

• More specific query• Operators

• Interaction with map and query• e.g. geolocation

• Select tweet• show tweets of selected user• Timeline of user• Create radius around tweet

• Create heatmaps

• Interaction with result area

FINThank you for your attention

Project can be found at: http://tweetmap.geohaupt.com

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