Learn More
Social microblogging services such as Twitter result in massive streams of georeferenced messages and geolocated status updates. This real-time source of information is invaluable for many application areas, in particular for disaster detection and response scenarios. Consequently, a considerable number of works has dealt with issues of their acquisition,(More)
Color coding is a widely used visualization method for scalar data. To generate expressive and effective visual representations, it is extremely important to carefully design the mapping from data to color. In this paper, we describe a color coding approach that accounts for the different tasks users might pursue when analyzing data. Our task description is(More)
The effective visual exploration of large and complexly structured, abstract data requires sophisticated and interactive visualization techniques. Development of these techniques is the major discipline in information visualization. On the other hand, visualization of geospatial data is an important topic in cartography. The necessity to combine expertise(More)
Data reflecting movements of people, such as GPS or GSM tracks, can be a source of information about mobility behaviors and activities of people. Such information is required for various kinds of spatial planning in the public and business sectors. Movement data by themselves are semantically poor. Meaningful information can be derived by means of(More)
Mobile and ubiquitous systems require task models for addressing the challenges of adaptivity and situation-aware assistance. Today , both challenges are seen as separate issues in system development, addressed by different modeling concepts. We propose an approach for a unified modeling concept that uses annotated hierarchical task trees for synthesizing(More)
Focus + context techniques are widely used for the efficient visualization of large data sets. However, the corresponding adaptation of the representation to the task at hand is not trivial, requiring a suitable model of the visualization goal. One type of focus + context technique is the use of lenses, interactive tools that modify the visualization in a(More)
Textual annotations are important elements in all but the simplest visual interfaces. In order to integrate textual annotations smoothly into the dynamic graphical content of interactive information systems, fast yet high-quality label layout algorithms are required. With the ongoing pervasion of mobile applications these requirements are shifted from(More)
In many application domains there is a strong need to produce content both for traditional print media and for interactive media. In order to fully benefit from digital devices, online documents must provide mechanisms to support interactivity and for the personalization of content. Thus, powerful authoring tools as well as flexible layout techniques are(More)