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.
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).
June 2, 2008
Wenjing Pu, "Travel time prediction on signalized urban streets using AVL buses as probes"
Department of Civil and Materials Engineering
University of Illinois at Chicago
Time: 1:30 pm
Location: 1000 SEO
The Chicago Transit Authority (CTA) is rapidly expanding their Bus Tracker system from route #20 to all CTA's routes. While the primary goal of the real-time bus tracking system is to provide timely information to transit users and operators and to improve transit services and managements, the system presents a potential opportunity to utilize the buses as probes to provide general vehicle travel time information for non-transit travelers. This study uses the data extracted from the Bus Tracker system implemented on route #20 and a VISSIM-simulated test bed based on Roosevelt Road to demonstrate the bus probe concept and further to develop a general methodological framework for real-time urban arterial travel time prediction using bus probes. The prediction framework consists of three steps: quantifying the relationships between bus travel and general vehicle travel, updating the bus speed and general vehicle travel profiles based on the new incoming stream of bus speed observations, and forecasting future travel times.
The first step is most critical as it is the basis of the entire study. Exploratory analyses of the Bus Tracker data and the test vehicle data will be presented first, followed by the statistical models including multiple linear regressions, seemingly unrelated regressions and multivariate state space models. The results have confirmed that there exist significant relationships between bus travel and general vehicle travel and reasonable non-transit vehicle travel times can be estimated. The second and third steps involve a Bayesian updating and a multivariate time series forecasting algorithm respectively. The results have shown it is possible to use the new incoming bus speeds and the forecasted bus speeds to derive reasonable concurrent non-transit vehicle travel times based on the relationships built in the first step.
The current study focuses on the feasibility, framework and algorithms in utilizing buses as probes. Further studies that focus on on-line data processing and broadcasting are needed to put the bus probe idea into real practices.
Wenjing Pu is a PhD Candidate in the Department of Civil and Material Engineering at the University of Illinois at Chicago. He holds a BS and a MS in Civil Engineering (Transportation) from Tongji University, Shanghai, China.