Priority Management for Urban Arterials. Transferability of Techniques: Methodology and Summary.

This paper describes the background and methodology employed in research funded by EPSRC to assess the effect of individual traffic control measures on urban arterials, both in isolation and in combination. The aim of the project was to test the transferability of the techniques developed in a DRIVE II project, PRIMAVERA, to a range of different types of urban corridor. Measures have been classed into three broad categories: Congestion Management, Public Transport Priority and Traffic Calming. The scope of these measures is wide, some operating at a junction level whilst others have an impact over a whole corridor. Measures from these categories are applied in a sophisticated microsimulation model of a series of hypothetical networks and four urban arterial corridors: three in Leeds and one in Leicester. The effects of the application of individual and integrated measures are assessed in terms of their efficiency, environmental and safety impacts using a form of Multi-Criteria Analysis. Travel time and other monetary costs are also taken into consideration. Whilst these results are of interest to local planners in the operation of each of the arterial corridors studied, a wider insight into the operation of urban arterials can be drawn from this study leading to more efficient control of the available road space

Priority Management for Urban Arterials. Transferability of Techniques: York/Selby Road.

This paper describes the background and methodology employed in research funded by EPSRC to assess the effect of individual traffic control measures, both in isolation and in combination upon urban arterials. The aim of the project was to test the transferability of the techniques developed in a DRIVE II project, PRIMAVERA, to a range of different types of urban corridor. Measures can be classed into three broad categories: Congestion Management, Public Transport Priority and Traffic Calming. The scope of these measures is wide, some operating at a junction level whilst others affect the whole network. Measures from these areas are applied to a sophisticated microsimulation model of four urban arterial corridors: three in Leeds and one in Leicester. The effects of the application of individual and integrated measures are assessed in terms of their efficiency, environmental and safety impacts using a form of Multi-Criteria Analysis. Travel time and other monetary costs are also taken into consideration. This paper reports the results for the A64 York and A63 Selby Road which are the main arterial routes to the east of Leeds.

Green Wave Traffic Optimization - A Survey

The objective of this survey is to cover the research in the area of adaptive traffic control with emphasis on the applied optimization methods. The problem of optimizing traffic signals can be viewed in various ways, depending on political, economic and ecological goals. The survey highlights some important conflicts, which support the notion that traffic signal optimization is a multi-objective problem, and relates this to the most common measures of effectiveness. A distinction can be made between classical systems, which operate with a common cycle time, and the more flexible, phase-based, approach, which is shown to be more suitable for adaptive traffic control. To support this claim three adaptive systems, which use alternatives to the classical optimization procedures, are described in detail.

MULTI-MODAL SIGNAL PROGRESSION DESIGN FOR ARTERIALS WITH HEAVY TURNING FLOWS

Most urban commuters have long been plagued by congestion in traffic networks and the resulting impacts on safety as well as travel time uncertainties. Since such undesirable traffic conditions in urban arterials are mainly at intersections, traffic researchers often rely on various signal control strategies to smooth traffic flows and minimize excessive delays. Although the advance in communications and control technologies over the past decades has enabled the traffic community to progress significantly on this regard, much, however, remains to be done to achieve the goal of having an efficient and safe traffic environment. Hence, this study has developed an integrated multi-modal signal progression system that allows the traffic engineers to apply different modules of the developed system to produce the best set of signal control plans that can effectively work under various constraints associated with arterial traffic patterns and roadway geometric features. The first primary function of the developed arterial progression system is designed to maximize the progression efficiency of passenger cars on a long arterial comprising heavy left-turn volumes, limited turning bay length, and near-saturated intersections. The developed system with such an embedded function can produce concurrent progression for both the through and left-turn movements with the least likelihood of incurring mutual blockage between them and uneven traffic queues among all critical locations on the arterial. To decompose a long arterial into the optimal number of control segments with well-connected and maximized progression bands, this study has further offered a function of a two-stage optimization process to tackle various critical issues that may prevent vehicles from progressing smoothly over the entire long arterial. To accommodate heavy passenger car and bus flows over an urban arterial and ensure the progression quality for both modes, this study has advanced the system with an innovative function that can offer concurrent progression to the best selected mode(s) and direction(s), based on traffic volume, bus ratio, and geometric conditions. By weighting the progression bandwidth with the passenger volumes and taking into account all critical issues that may result in their mutual impedance, such an embedded function of the developed arterial control system can achieve the objective of maximizing the benefit for all roadway users and for all modes. Most importantly, to ensure the effectiveness of the developed system’s key functions under various arterial traffic patterns and control objectives, this study has integrated all key modules developed for, such as, the arterial signal design, allowing users to contend with most challenging scenarios, concurrently decomposing a long arterial into the optimal number of control segments for both modes, maximizing their progression bands within their respective segments, circumventing all geometric constraints, and balancing the progression length and bandwidth between the competing modes. In view of computing efficiency associated with the execution of all interrelated optimizing functions, this study has also designed a customized algorithm to minimize all computation-related tasks. Rigorous evaluation with extensive numerical studies has verified the effectiveness of the developed arterial system’s key functions, and evidenced their contributions with respect to offering best progression and minimizing traffic delays. The developed system’s flexibility in circumventing various roadway constraints and traffic queue spillback has also been confirmed from the results of comprehensive simulation experiments with different critical traffic scenarios

Regional Data Archiving and Management for Northeast Illinois

This project studies the feasibility and implementation options for establishing a regional data archiving system to help monitor and manage traffic operations and planning for the northeastern Illinois region. It aims to provide a clear guidance to the regional transportation agencies, from both technical and business perspectives, about building such a comprehensive transportation information system. Several implementation alternatives are identified and analyzed. This research is carried out in three phases. In the first phase, existing documents related to ITS deployments in the broader Chicago area are summarized, and a thorough review is conducted of similar systems across the country. Various stakeholders are interviewed to collect information on all data elements that they store, including the format, system, and granularity. Their perception of a data archive system, such as potential benefits and costs, is also surveyed. In the second phase, a conceptual design of the database is developed. This conceptual design includes system architecture, functional modules, user interfaces, and examples of usage. In the last phase, the possible business models for the archive system to sustain itself are reviewed. We estimate initial capital and recurring operational/maintenance costs for the system based on realistic information on the hardware, software, labor, and resource requirements. We also identify possible revenue opportunities. A few implementation options for the archive system are summarized in this report; namely: 1. System hosted by a partnering agency 2. System contracted to a university 3. System contracted to a national laboratory 4. System outsourced to a service provider The costs, advantages and disadvantages for each of these recommended options are also provided.ICT-R27-22published or submitted for publicationis peer reviewe

Philadelphia Traffic Operations Center: Concept of Operations

This document defines the concept of operations for the proposed Philadelphia Traffic Operations Center. It defines the center's goals, capabilities, and features to be phased in over the next five-plus years. Operational policies, support environment, and traffic management center practices are also recommende

A Real-time Signal Control System to Minimize Emissions at Isolated Intersections

Continuous transportation demand growth in recent years has led to many traffic issues in urban areas. Among the most challenging ones are traffic congestion and the associated vehicular emissions. Efficient design of traffic signal control systems can be a promising approach to address these problems. This research develops a real-time signal control system, which optimizes signal timings at an under-saturated isolated intersection by minimizing total vehicular emissions. A combination of previously introduced analytical models based on traffic flow theory has been used. These models are able to estimate time spent per driving mode (i.e., time spent accelerating, decelerating, cruising, and idling) as a function of demand, vehicle arrival times, saturation flow, and signal control parameters. Information on vehicle activity is used along with the Vehicle Specific Power (VSP) model, which estimates emission rates per time spent in each operating mode to obtain total emissions per cycle. For the evaluation of the proposed method, data from two real-world intersections of Mesogion and Katechaki Avenues located in Athens, Greece and University and San Pablo Avenues, in Berkeley, CA has been used. The evaluation has been performed through both deterministic (i.e. under the assumption of perfect information for all inputs) and stochastic (i.e. without having perfect information for some inputs) arrival tests. The results of evaluation tests have shown that the proposed emission-based signal control system reduces emissions compared to traditional vehicle-based signal control system in most cases

An assessment of VMS-rerouting and traffic signal planning with emission objectives in an urban network — A case study for the city of Graz

This paper discusses a case study evaluating the potential impact of ITS traffic management on CO 2 and Black carbon tailpipe emissions. Results are based on extensive microsimulations performed using a calibrated VISSIM model in combination with the AIRE model for calculating the tailpipe emissions from simulated vehicle trajectories. The ITS traffic management options hereby consist of easily implementable actions such as the usage of a variable message sign (VMS) or the setting of fixed time signal plans. Our simulations show that in the current case shifting 5% of vehicles from one route to another one leads to an improvement in terms of emissions only if the VMS is complemented with an adaptation of the signal programs, while the VMS sign or the change of the signal plans alone do not yield benefits. This shows that it is not sufficient to evaluate single actions in a ceteris paribus analysis, but their joint network effects need to be taken into account

Queue Discharge at Freeway On-Ramps Using Coordinated Operation of a Ramp Meter and an Upstream Traffic Signal

Ramp metering is an effective way of maintaining optimum traffic conditions and mitigating congestion on freeways. Several strategies for ramp metering exist in the literature. They are typically based on the freeway traffic parameters as control inputs to the ramp control logic. The ramp signal can be controlled in two ways, i.e., locally controlled (isolated ramp control) and coordinated ramp control. Coordinated ramp control refers to the ramp metering strategies in which several ramp meters connected to the freeway segment are dynamically controlled by considering traffic flows along all ramps. Coordinated ramp metering can play a vital role in freeway congestion mitigation on the ramps as well as normalize the traffic flow over the freeway. In this study, an alternate coordinated metering scheme that uses the state of the upstream traffic signal on arterial as the control input to the ramp meter is proposed. The proposed method aims to prevent long queues on the ramp with limited storage by taking feedback from the upstream traffic signal on the arterial, especially when the ramp has a small storage area for vehicles. Simulation results show a significant reduction in the queue length over the ramp using the proposed scheme. Additionally, the proposed scheme also benefits the arterial traffic. 2020 The Authors. Published by Elsevier B.V.All rights reserved.Scopu