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10 What new analysis tools might become possible using this Table 1. Agencies interviewed in wide kind of archived data? telephone survey. State/ City / Area Agency 1.3 Research Approach Province CA San Jose Valley Transportation The research followed three major thrusts, described in this Authority section: CO Denver Regional Transportation District FL Broward County Broward County Transit Survey of industry practice FL Orlando LYNX Analysis of data systems and opportunities IA Des Moines Metropolitan Transit Authority Development of analysis tools IA Sioux City Sioux City Transit IL Chicago CTA 1.3.1 Survey of Practice: Breadth and Depth IL Chicago suburbs Pace MA Cape Cod Cape Code Regional Transit Six information sources were used to review (1) AVL, APC, Authority and related systems with respect to their ability to capture and MD Baltimore / state Maryland Transit Administration archive operational data and (2) industry practice in using MI Ann Arbor Ann Arbor Transportation such archived data. Together, these sources provide both a Authority broad view of historical and current practice and an in-depth MN Minneapolis Metro Transit view of practice at transit agencies in the United States, MO Kansas City Kansas City Area Transportation Authority Canada, and Europe. NJ New Jersey (statewide) NJ Transit The first source was the literature on intelligent systems in NY Buffalo Niagara Frontier transit and on transit analysis tools. A helpful starting point Transportation Authority was a pair of state-of-practice reviews done for the U.S.DOT's OR Portland Tri-Met Volpe Center (4, 5). TX Dallas Dallas Area Rapid Transit A second source was a mail survey of U.S. transit agencies TX San Antonio VIA concerning their use of AVL and APC systems conducted in WA Seattle King County Metro Spring 2001 by Robbie Bain. WI Milwaukee Milwaukee County Transit AB Calgary Calgary Transit A third source was a wide telephone survey of APC and AVL AB Edmonton Edmonton Transit users. From the first two sources, the researchers assembled a BC Vancouver TransLink preliminary list of some 122 U.S., 14 Canadian, and 26 Euro- BC Victoria BC Transit pean transit agencies using or planning to use AVL or APC sys- MB Winnipeg Winnipeg Transit tems. From that list, staff members were telephoned at transit NS Halifax Halifax Metro Transit agencies reputed to be advanced in their use of AVL or APC ON Hamilton Hamilton Street Railway data. Telephone interviews were successfully conducted with ON London London Transport the 20 U.S. and 14 Canadian transit agencies listed in Table 1. Commission ON Ottawa OC Transpo The fourth source was in-depth case studies at nine transit ON Toronto Toronto Transit Commission agencies in the United States, Canada, and the Netherlands, QC Hull Socit de transport de listed in Table 2. Appendixes A through I of TCRP Web Doc- l'Outaouais ument 23 (available from the TRB website: www.trb.org) con- QC Montreal STM tain the case study reports. In addition, a partial case study QC Montreal South Shore Socit de Transport de la was conducted of Uestra, the transit agency in Hannover, Rive Sud de Montreal QC Quebec Socit de transport de la Germany. Communaut urbaine de The nine case study agencies provide a broad range in Quebec many respects. They represent the United States, Canada, and Europe. Within the United States, they span the East Coast, Midwest, and West Coast and include agencies whose oper- well-established practice with archived data, with impacts ations are statewide, metropolitan, and limited primarily to throughout the organization; others are still in the devel- a central city. Some have focused on AVL; others on APCs; opment stage. These agencies have had failures as well as others on event recorders; and some on two or more of successes, and lessons are learned from both. these functions. They represent a range of vendors, system A brief description of the AVL-APC systems at the case design, and system age. Some of the selected agencies have study sites will provide some helpful background.

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11 Table 2. Case study sites. At NJ Transit, an AVL vendor supplied the on-board com- puter with location tracking function, even though NJ Location Agency Appendix Transit's system is not connected to a radio, and integrated Portland, OR Tri-Met A it with APCs. Only a fraction of the fleet is instrumented; New Jersey (statewide) NJ Transit B that fraction has been concentrated on one route to make Seattle, WA King County Metro C operations analysis of that route possible. It features exten- Chicago, IL CTA D sive and frequent event recording, including stop records, Montreal, QC STM E Ottawa, ON OC Transpo F and was designed to enable later integration with the radio Eindhoven, the Netherlands Hermes G and other devices through a J1708 network. The Hague, the Netherlands HTM H At Metro Transit, the AVL vendor supplied the on-board Minneapolis, MN Metro Transit I computer, which is connected to the radio and, on 12% of the fleet, to APCs. The radio carries both round-robin poll data (bus location when polled) for real-time monitoring Tri-Met's system features on-board computers on all of and event messages. Off-line analysis will ignore the poll their buses, connected by radio to provide real-time AVL, data except for incident investigations, and instead use event and stores on-board records for every stop as well as other messages, including timepoint messages. Stop messages, events. APCs are on about 65% of the fleet. Stop records including passenger counts, are not recorded on board, but include on and off counts (void for buses without APCs), are transmitted by radio whenever an APC-instrumented stop ID, longitude, latitude, door open moment, dwell bus actually serves a stop. During periods of radio failure, event messages are recorded on board, uploaded at the end (i.e., door open) duration, moment of exiting a 30-m radius of the day, and inserted into the radio message database. zone around the stop, indicators of door opening and lift King County Metro has both AVL and APC systems that use, and maximum speed since the previous stop. Location share signpost, odometer, clock, and operator login (route/ and status are radioed to the control center on an exception run) information, but are otherwise independent. The AVL basis (e.g., when more than a predetermined deviation from system sends timepoint messages as well as performs round- schedule occurs or when the bus is off route). Operator- robin polling. Service analysts at King County Metro had initiated coded radio messages (e.g.,"road blocked by train" long relied on APC records for operations analysis; however, or "pass-up") are recorded in the on-board computer with because of improvements in timepoint detection made time and location stamp as well as transmitted in real time. around 2000, AVL timepoint data is now the preferred data The on-board computer is also connected to a traffic signal source, because AVL data is implemented fleetwide, offer- priority request emitter, triggered only when the bus is ing large and recent data samples. behind schedule. OC Transpo and Societ de Transport de Montral (STM) The HTM (the Hague) system is like Tri-Met's, featuring have stand-alone APCs. OC Transpo is a long-time APC on-board event recording at every stop, APCs on a frac- user and has used its APC system extensively for opera- tion of the fleet (in this case, about 25%), radio transmis- tions analysis as well as passenger count analysis. STM has sion of real-time location to central control, and traffic recent in-depth experience in testing and approving new signal priority request emitters. APC systems. Eindhoven's Hermes system is an event recorder, not con- nected to the radio. Location is based on sub-pavement bea- The fifth source of information was a 1-day workshop for cons at each signalized intersection and odometer. Stop vendors held on May 28, 2002. An open invitation was records include door opening and closing time. Records extended to vendors of AVL, APC, and related products, with are also made of each time the bus passes a 5 km/h speed specific invitations sent to known vendors. They were joined threshold, used to determine how much time is spent by panel members, representatives of several of the case study stopped or at crawl speed at different points on the route. sites, and members of the project team, providing a good rep- A stop announcement system currently being installed at resentation of interested transit agency staff and independent the CTA stores stop records on board all buses. On buses researchers. Participants other than project team members with APCs (15% of the fleet), stop records include on and are listed in Table 3. The researchers also benefited from direct off counts. At the same time, an independent 1995-vintage interaction with vendors referred by transit agency staff from AVL system polls buses for their location every 40 to 70 s. the case study sites. Although the poll messages are recorded, they are not Finally, the researchers used their knowledge of the transit matched to location and are therefore unsuitable for routine industry and related industries, supplemented by informa- operations analysis. tion received from members of the project panel.