Integrating transportation systems management and operations into the project life cycle from planning to construction： A synthesis of best practices

Guided by the federal highway administration （FHWA）, many states are promoting the implementation of transportation systems management and operations （TSM＆O） pro- grams. TSM＆O is traditionally managed by traffic engineers that focus on optimizing ef- ficiency and operations within a particular corridor utilizing common techniques such as re-timings and access modifications. With the emphasis moving towards maximizing current infrastructure, the practice of managing TSM＆O can be applied to all units and disciplines, within a transportation entity, for increased efficiency. One main reason of the stagnated integration is the lack of policies which could support the integration of TSM＆O strategies within the planning or design stages. This paper provides detailed guidance on how to apply TSM＆O strategies from the planning stages to the construction phase of any general transportation project. TSM＆O programs established around the nation are dis- cussed to understand the current initiatives underway and the best practices to create a robust and performance-based program. The developed TSM＆O project cycle process provides a detailed structure for the potential interactions between phases of a project and department staff as a key to ensure that the program achieves the highest level of opti- mization. Continuous evaluation must be undertaken by the agencies to ensure that theperformance of the system is at an optimal level. Developing performance measures, which accurately describe the objectives of the agency, is critical to ensure the plan to be brought to practice.

A peer-to-peer logic environment to validate flashing yellow arrow decision support system

The flashing yellow arrow(FYA)signal display creates an opportunity to enhance the leftturn phase with a variable mode that can be changed on demand.This research develops an integrated general purpose data collection module that time stamps detector and phase state changes within a National Electrical Manufacturers Association(NEMA)actuated traffic signal controller to provide recommendations for the flashing yellow arrow left-turn mode on a cycle-by-cycle basis.115 left-turn approaches at 38 intersections with locations across the State of Florida were analyzed totaling 1370 h of video data processed including off-peak and peak conditions.Video data extraction was an essential step in developing thegap thresholds for the permissive left-turn.Actual intersection field data were obtained through loop detector mapping to the controller in the lab in real-time mode using a peerto-peer logic environment.A custom communications software was developed to retrieve instantaneous channel input data,synchronize opposing through green phase,analyze traffic information,provide the algorithm decision,and generate a real-time log recording the events to determine whether it would be optimal to switch the red arrow to a flashing yellow arrow.The algorithm determines the time interval between the successive arrivals of vehicles and computes the corresponding headway for each lane by cycle on a secondby-second basis.Peer-to-peer logic is a necessary step to verify and validate new traffic concepts prior to field-testing and offers the advantage of acquiring and analyzing realtime traffic data coupled with video feed with the benefit of a safe environment.

Congestion pricing strategies to investigate the potential of route diversion on toll facilities using en-route guidance

The application of intelligent transportation systems （ITS） technologies to facilitate the traffic mobility requires dynamic routing decisions. This study examines the effectiveness of Paramics, a microscopic traffic simulation model that uses a link-to-link shortest path algorithm to consider both updated link travel times and incident conditions detected through different traffic assignment techniques. This paper describes modeling of an urban highway network＇s traffic conditions to investigate potential route diversion through congestion pricing strategies on toll facilities in Orlando, Florida using Paramics. The experimental design included a multi-level factorial design with three qualitative variables and four response quantitative variables. The experiment＇s objective was to investigate different scenarios for reducing tolls on less congested roads （SR528 and SR417） and increasing tolls on more congested roads （SR408） to determine the impact on travelers＇ route choices and overall congestion in the network. The simulation results demonstrate that the Dynamic Feedback Assignment （DFB） led to a reduction in the average queuing delay and average travel time when compared to results from the Stochastic Assignment （SA）. DFB significantly affected the percentage of diversion in the network. Drivers saved 10%-16% of travel time when DFB information was provided. Results also show that percentages of route diversion vary from one route to another and depending on the travel cost between specific origin-destination pairs. While drivers incorporate real time guidance information to maximize their own utility, not all drivers gain the same benefit. This was attributed to the limited extra capacity of the alternative routes and the longer travel distance. Combining congestion pricing strategies with traffic information maximize travel time benefits.