Information about local busses: http://www.vgs-online.de/cgi-bin/query.exe/en? The closest stop for DFKI is "Universiität Mensa"
Some hotels one can consider (but you can check your usual hotel reservation service):
City Hotel - website
bus stop: Haus der Zukunft, ca. 17 min. to university, 10 min. to central station
Madeleine - website
bus stop: Johanneskirche, ca. 16 min. to university, 6 min. to central station
Gästehaus Weller - website
bus stop: An der Trift, ca. 12 min. to university, 12 min. to central station
Ibis Hotel - website
bus stop: Roonstraße, ca. 25 min. to university, 13 min. to central station
Hotel Leidinger - website
(bus stop: Landwehrplatz, ca. 25 min. to university, 11 min. to central station
Youth Hostel - website
bus stop: Prinzenweiher/DJH, ca. 11 min. to university, 13 min. to central station
Detailed information (prices etc.) and more hotels can be found in this hotel list.
