Privileged Information
2004 Meeting Minutes
TRB AHB45 (A3A11):
Committee on Traffic Flow Theory and Characteristics (TFT)
Marriott, Washington B4, Wednesday, January 14, 2004, 2:30-5:30 pm
1. Welcome
Nathan Gartner (UML) welcomed all attendees as Chairman of the (newly renamed)TRB AHB45 TFT Committee (formerly A3A11). Edmond Chang (EDCPC) served as Committee Secretary and recorded the TRB TFT committee meeting minutes.
2. Self-Introductions
Brief self-introductions were made by a total of 80+ members and friends that attended the meeting. The TRB AHB45 Committee consists of a diverse group of members including substantialinternational attendance. Members come from the US/Canada (80%), Europe(10%), and Asia(10%). The members’ backgrounds are approximately50% academic, 30%government, and 20% private industry.
3. Minutes Approval
It was moved and seconded that the TFT Committee Meeting Minutes for the last meeting held January 15, 2003 (emailed previously and available at the committee website be approved. Minutes were approved unanimously.
4. Chairman’s Report
Nathan Gartner (UML) recognized Dan Turner (TRB Operations Group Chairman) who discussed the recently-completed reorganization of the TRB Operations Group. The reorgani-zation was designed to better reflect issues of national importance, cross-cutting issues, customer-oriented approach, and future directions in the strategic plan efforts. There will be a new focus on safety and security. Principal among them is the incorporation of the TRB ITS Committee (AHB15) in the Operations Group.
Nathan Gartner (UML) introduced twonew appointees to the TFT Committee: Do Nam and Serge Hoogendoorn. Markos Papageorgiou which was also re-appointed. Chairman Gartner reported briefly on the informal mid-year committee meeting which was held in Barcelona, Spain in June 2003 in conjunction with the FHWA sponsored Workshop on Traffic Modeling: Trends and Challenges. He reviewedthe very successfulWorkshopsonTraffic SimulationModels which were held during the TRB meetings of2003 and 2004 with 200+ attendees each (more on that below). He informed the committee that as part of the self-evaluation process we need to revise the TFT Committee Strategic Plan and submit it for review in May 2004.
5. TRB Report (by Rich Cunard)
Rich Cunard (TRB Staff Representative) gave the TRB Staff report: 7,200 people registered for the meeting, 11% from overseas. State participation is down due to state budget problems and travel restrictions. A total of 2,500 papers were submitted (about 15% increase from 2003). Notably, this year more than one third of all papers presented were in poster sessions. A total of 28% of papers will be accepted for publication in the TRR series. The 2005 Annual Meeting will be held January 9-13, 2005, the 2006 Annual Meeting will be held January 22-26, 2006and the 2007 Annual Meeting will be held January 21-25, 2007. TRB has considered options for changing the location of the annual meeting to the WashingtonConvention Center, but there are disadvantages with respect to the lack of meeting space and nearby hotel rooms. Other options include looking at “no Wednesday night” sessions, or continuing with the present format.
The web-based electronic submission/review process continues to be very successful. The process will be continued with more committee customized features, providing review scores across reviewers/committees, and will keep track of the secondary review process in 2004. Paper reviewers reviewed an average of 2.3 papers each, with the 85th percentile at 5 papers reviewed. Four percent of reviewers reviewed more than 10 papers.
TRB Committees were reorganized and restructured to increase the interactions, separate/elevate groups/modes (rail, port, and safety), and highlight cross-cutting issues. Under the new organi-zation, the TFT Committee is a part of the Operations & Maintenance Group A3000 and the TFTCommittee’s new number is AHB45.
The “Interactive Program Planner” on the TRB website was very useful and highly used for meeting planning, and is usable for downloading to PalmPilots and other PDAs. The password-protected features may be improved so that users’ input can be protected. The CD-ROM contains 1,486 papers or 95% of the papers being presented in PDF format. Comments were raised on how to improve the poster sessions, how to submit discussion papers by mid-February 2004 (see note that a link to this page has been added to the TFT Committee website), and providing a Listserv service on the TRB website. All 2003 TRB publications should be available in hard copy by January 31, 2004.
Please relay all comments to Rich Cunard at .
6. TRB Paper Review and Sessions (Nathan Gartner)
In 2004, the TFT Committee received over 80 papers, and some that were jointly reviewed with other committees. Approximately 30 papers were submitted in response to the TFT Committee’sspecific Call-for-Papers on Calibration and Validationissues. In addition, TFT Committee members and friends were assigned 356 papers for review, with 317 actual completed reviews. Peter Wagner and Christine Buisson, originators of the Call-for-Papers, took a major part in reviewing the additional papers that were submitted as a result.
With an average of 4 reviewers per paper, 4 papers have been directly accepted for publication, 20 papers were requestedto be revised and re-reviewed before publication, decisions on 16 papers will be made after the Annual Meeting, and 31 were rejected for publication. There is a 28% publication quota based on the number of papers submitted. Thus, 24 papers will be published with 16 in suspension that may or may not be published. The review process also resulted in 52 papers accepted for presentation and 23 papers rejected for presentation. This year, fourpodium paper sessions were scheduled, with 30 papers presented in two poster sessions.
Committee discussion was generally favorable on the poster sessions, except for the fact that the room layout was deficient (aisles were much too narrow). Committee recommendations on publication will be given by February 1, 2004, and the revised papers will need to be submitted by April 1, 2004 to meet the established TRR 2004 publication schedule.
All the reviewers indicated that the electronic submission/review definitely facilitated the TRB paper review process, resulting in a higher response rate from reviewers. It was suggested by committee members to add the capability to add equations on the website. As usual, TRB also encourages members to submit TRB discussion papers with advanced notice by February 15, 2004(see
There was some discussion of the future of the TRR—the CD could be kept as the Proceedings of the Annual Meeting, with the TRR as a stand-alone journal. There was further discussion of the review process, particularly the review scoring. Some committees ignore the review scores, some apply weighting factors and others use the “outlier” reviews as an indication of the reviewer and the paper. The system allows the paper coordinator to see how a reviewer rates all papers reviewed.
The review process does not currently allow a process for second stage reviews (after the Annual Meeting), and there is no place to include the author’s responses. This will be addressed in the next version of the software to allow more convenient second stage reviews.
7. FHWA Report (Henry Lieu, John Halkias and Gene McHale)
Henry Lieu, John Halkias, and Gene McHale jointly presented the FHWA Report. Henry Lieu reported that the “FHWA Performance Plan” on the FHWA R&D activities is available through the FHWA website at:
Henry Lieu reported that the latest TSIS 5.2, with improved multiple-run capability, revised GUI, user-friendly postprocessor, signal control/transition logics, and export capability to spreadsheet, has been finished and will be released by McTrans in February 2004. FHWA Minnesota Division has completed an Advanced CORSIM Manual, reporting on theirexperience using CORSIM in Minnesota (available at
Henry Lieu (FHWA) reported that the DTA project has moved from “Research” to“Field Deployment” mode. A total of four prototype "DTA/TrEPS" are available, field test, and Beta version is complete for both off-line and on-line applications. The systems are being tested in LA, TX, VA, and FHWA is currently selecting partnerships for real-time, on-line, advanced traffic management applications. All the reports, presentations, and prototype software are available through the DTA website:
The ACS-Lite project is ongoing to take advantage of the closed-loop signalized systems currently available in United States. The information is available at the Traffic Signal Systems website: QuickZone 2.0, scratch tool, is available through the McTransCenter. QuickZone is being identified and developed for addressing work zone activities, and is available for download at FHWA is also improving the detailed intersection collision modeling in the Texas model. FHWA has supported the new HCM features. Paul Pisano (), described some of the key factors to better research the road-weather information programs as well as the traffic-user behavior model in the CORSIM model within the Traffic Management and Operations Division.
John Halkias and Gene McHale jointly reported on the ongoing NGSIM development. All the information will be available on the FHWA Operations website. The work plan for developing the prioritized algorithms is available by the end of December 2003. Reviewers are sought for the model, reports, and guidelines. All the information of the traffic analysis tool primer and traffic simulation guidelines are available at
8. TFT Monograph (Hani Mahmassani)
FHWA sponsored the development and revision activities, currently under contract through the Transportation Research Board (TRB) and Oak Ridge National Laboratory (ORNL). Final revision is completed on the MS Word version for final publication by TRB staff. The last version was postedFebruary 2003 on both the FHWA and ORNL websites after extensive reviews from the TRB TFT Committee, see:
Additional minor editorial updates will be completed and the monograph will be forwarded to the original authors and TRB for final editing and publication. A Special Report format will be used to publish the hardcopy of the “TFT Monograph” with potential publication in late2004.
- Cooperation with Other Committees (Nathan Gartner)
Over 150+ participants attended the “Traffic Simulation Models” Workshop that was held on Sunday January 11, 2004 which was organized and chaired by Nate Gartner (TFT). It was organized in cooperation with the committees on Traffic Signal Systems, Highway Capacity, and Freeway Operations. The workshop focused on FHWA initiatives, reports from applications, calibration issues and new directions. A copy of the workshop agenda is attached to these minutes. It was the consensus of the discussion that this series of workshops should be continued in cooperation with the other committees.
The Joint Simulation Subcommittee, AHB45(1), has been formed with membership from the TRB TFT, HCM, FWY, and TSS Committees. The inauguralsubcommittee meeting was held on Monday, January 12, 2004. Rick Dowling (chair of the Highway Capacity committee) was present and noted his committee’s interest as simulation tools are becoming more sophisticated and analytical procedures are relying more and more on simulation.
The subcommittee has identified several initial key activities: (1) define and refine the proposed scope of activities, (2) continue the Simulation Workshop in 2005, (3) identify and prepare research problem statements to realize the follow-up opportunities, (4) calibration and validation of simulation models, and (5) determine how the TFT committee can participate more actively in simulation model activities. Much discussion ensued among committee members about how to participate more actively in the traffic simulation modeling activities, emphasizing the users’ needs, developing consensus, and fine-tuninga white paper being drafted by Ken Courage (UFL) to be circulated to the TFT Committee.
11. Committee Website (R. Bertini)
A committee website has been established by Robert Bertini, with all the committee information posted, self prescribed e-Mail server, full-function discussion group, and updated workshop presentations on the website linked through the TRB website. All the privileged information is protected with the username: a3a11, password: tft.
- Other Sub-Committee Activities (All)
Paper Review Sub-Committee continued. The TRB2005 TFT Workshop Sub-Committee was established. A joint simulation sub-committee has been established with HCQS, FWY, TSS, and other committees as well.
Possible additional sub-committees for consideration are:
Strategic Planning Sub-Committee to address committee scope; Developers/Users’ Interests; and a Joint Task Force on “Traffic Analysis Tools.”
Paul, Ed, Hani, Henry, Edmond, Jim, Thanasis, Panos, Alex, and John volunteered to participate on the “Joint Modeling Task Force” if and when established as representatives of the TFT Committee.
Needs exist for the TFT Committee to: participate in the ongoing ITSA/USDOT "DOT Research Agenda," to follow-up on action plans with inputs from both committee members and friends.
The need for active involvement in the traffic simulation model development by the TFT Committee was raised. These efforts may include participation in the DOT/FHWA NGSIM research activities, involvement in the Conference/Workshop on "Existing Simulation Models" and “End Users’ Experience.”
13. Conferences and Workshops
Hani Mahmassani (UMD) reported the current status for the preparation of the ISTTT Symposium to be held at University of Maryland on July 19-21, 2005. The Call-for-Papers will be available in February 2004. Future venues will be considered for a mid-year Committee meeting with a potential simulation workshop in conjunction with the ISTTT Symposium.
A simulation workshop is planned to be held in Tucson, AZ in August 2005.
AATT2004 will be held in Beijing, ChinaMay 26-28, 2004.
A Call-for-Papers was distributed for the Special Issue of the ASCE Journal of Transportation Engineering: Calibration and Validation of the Highway Capacity Manual (HCM) Models. Papers are due by March 1, 2004.
The TFT Committee is considering several possibilities for Mid-Year meetings in 2005 and 2009. The TRB HCQS, and TSS Committee is planning a Joint Mid-Year Meeting and Workshop on “Traffic Signals in HCM” to be held in Las Vegas, NV on June 20, 2005. TheHCQS Committee is also planning a Joint Mid-Year Meeting in State College, PAJuly 28-30, 2004. Reinhard Kuehne also suggested hosting a Mid-Year Committee meeting inColumbus, OH in 2009 to celebrate the 80th Anniversary of the famous “Greenshields” publication.
A better definition of the “Distinction Between Gaps and Headways” has been prepared by Rod Troutbeck for the TFT Committee Members’ input and isattached.
Hani Mahmassani (UMD) invites the submission of TFT papers for the “Transportation Science” Journal which he is editing.
14. Adjournment
The TFT Committee adjourned at 5:30pm.
AGENDA
Committee on Traffic Flow Theory and Characteristics
Wednesday, January 14, 2004, 2:30 – 5:30 PM
Washington B4 – Marriott Wardman Park Hotel
Washington, D.C.
1.Welcome and Call to OrderNH Gartner
2.Introductions – Members & FriendsAll Attendees
3.Approval of Minutes – TFT&C
- Committee Meeting of January 15, 2003ECP Chang
4.Chairman’s ReportNH Gartner
5.TRB Report – Staff RepresentativeRich Cunard
6.Paper Review and SessionsNH Gartner
- Call for papers on “Calibration & Validation”
8.Traffic Flow Theory MonographH Mahmassani
9.FHWA Activities - ReportHenry Lieu
- Cooperation with other committeesNH Gartner
-Mid-year meeting
-Workshop on Traffic Simulation Models
-Joint Sub-committee on Traffic Simulation Models
11.Other Sub-Committee ActivityAll Attendees
12.Committee WebsiteRobert Bertini
13.Conferences, Symposia, Workshops
14.Announcements and Future Meetings
15.New Business
> Adjournment <
WORKSHOP ON TRAFFIC SIMULATION MODELS(Session 148)
2004 TRB Annual Meeting, Washington, D.C.
Sunday, January 11, 2004
Omni Shoreham Hotel, Empire Room, 2:00 – 5:30 pm
The TRB Committees on Traffic Flow Theory and Characteristics and on Highway Capacity and Quality of Service, are co-sponsoring this workshop to address recent advances in the development and application of traffic simulation models in the design, evaluation and operation of modern transportation facilities.
PROGRAM
2:00 ~ 2:10Introduction to Workshop
Nathan H. Gartner, University of Massachusetts, Lowell
2:10 ~ 2:30Report on Barcelona/Sitges Workshop
Pitu Mirchandani, University of Arizona
Jaime Barcelo, UP-Catalunya (Spain)
2:30 ~ 3:00Calibration and Validation of Simulation Models- A Tutorial
Christine Buisson, INRETS (France)
Peter Wagner, DLR (Germany)
3:00 ~ 3:30Traffic Simulation Guidelines
Rick Dowling, Dowling Assoc.
Alex Skabardonis, UC - Berkeley
3:30 ~ 3:45COFFEE BREAK
3:45 ~ 4:45NGSIM Developments
- Overview of Program
John Halkias, Gene McHale, FHWA
- A Status Update
Vassili Alexiadis, Cambridge Systematics
- High Level Data Plan
Robert Hranac, Cambridge Systematics
- Algorithm Prioritization
Vassili Alexiadis, Cambridge Systematics
4:45 ~ 5:15Decision Support Methodology for Selecting
Traffic Analysis Tools
Krista Jeannotte, Cambridge Systematics
5:15 ~ 5:30TRB ACTIVITIES, DISCUSSION & CLOSURE
Distinction between gaps and headways
Rod Troutbeck
January 2004
The traditional definition of a “headway” is the time interval between the front of a vehicle passing a point and the front of the next vehicle passing the same point. Headways include the time for a vehicle to be on or over the point (or occupancy).
A gap, on the other hand, is the clear time between the passage of one vehicle and the passage of the next. It excludes the time for a vehicle to pass the reference point.