CTS Events
November 14, 2012

Dr. Nebiyou Tilahun, UPP, presents a seminar entitled "An agent based model of origin destination estimation (ADOBE)" Wednesday, November 14th at 4:00 pm in Rm 1127 SEO


November 7, 2012

Mr. Thomas Murtha, CMAP, will address the CTS-IGERT community at 4:00 p.m. in Room 1127 SEO.


October 24, 2012

Please join us in welcoming Dr. Bo Zou, CME, on Wednesday, October 24th, Room 1127 SEO, 4:00 p.m.


CTS Happenings
September 25, 2012

Award Received by Joshua Auld, CTS-IGERT alumnus.


April 20, 2012

Congratulations to James Biagioni, CTS Fellow and CS PhD candidate, winner of the Dean's Scholar award.


January 2, 2012

James Biagioni, CTS Fellow, receives "Best Presentation Award" at SenSys2011


July 30, 2010

Dr. Ouri Wolfson, Dr. Phillip Yu, and Leon Stenneth, CS student and CTS Associate, recently had a paper accepted to the 6th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob 2010).


November 10, 2008

Dr. Matthias Renz, "Managing and Mining Traffic in Road Networks"

Dr. Matthias Renz
University of Munich
Institute for Computer Science
Database and Information Systems
Time: 2:00 pm
Location: 1000 SEO

Recently, modern tracking methods started to allow capturing the position of massive numbers of moving objects. Furthermore, with the spreading of modern mobile devices like PDAs or car navigation systems, location-based services (LBS) became more and more important. One key issue in many LBS applications is the detection of proximity among moving objects in a traffic network. Special techniques providing efficient query processing on moving objects on road networks are very important. Furthermore, effective and efficient methods for traffic analysis are required. Methods for analyzing and predicting the traffic density in a network offers valuable information for traffic control, congestion prediction and prevention. In this talk, I will present our recent approaches for managing and mining traffic in road networks.

The first part of the talk is about proximity monitoring in road networks. Thereby, we consider the following scenario: a set of mobile objects continuously track their positions in a road network and are able to communicate with a central server. The server which gets position updates from the moving objects has to detect the event that two objects reach or exceed a specified proximity distance. This way, the server is permanently aware of all pairs of objects that are within a certain distance range. Obviously, the communication costs between the objects and the server quickly become the bottleneck if a position update is sent to the server at each tracking time slot. I will propose update strategies in order to reduce the communication overhead by defining special regions for each object. These regions are defined such that no position updates at the server are required as long as the objects do not leave their corresponding regions. In particular I will present efficient algorithms for updating these regions and detecting proximity/separation when objects leave their corresponding regions.

In the second part of this talk I will propose a novel statistical approach to predict the density on any edge of such a network at some time in the future. Our method is based on short-time observations of the traffic history. Therefore, knowing the destination of each traveling individual is not required. Instead, we assume that the individuals will act rationally and choose the shortest path from their starting points to their destinations. Based on this assumption, we introduce a statistical approach to describe the likelihood of any given individual in the network to be located at a certain position at a certain time. Since determining this likelihood is quite expensive when done in a straightforward way, we propose an efficient method to speed up the prediction which is based on a suffix-tree.

Matthias Renz got one master in electrical engineering and one in computer science. Before starting his phd studies he worked at the institute for robotics at the German Aerospace Center. In 2006 he finished his phd at the university of munich. Currently, he works in the group of Hans-Peter Kriegel at the Ludwig-Maximilias-University Munich (LMU). His main research interests are in the fields "Query Processing in Uncertain Object Databases", "Spatio-Temporal Data Mining" and "Similarity Search in Spatial, Temporal, and Multimedia Databases'.