Unambiguous metrics for evaluation of traffic networks

Transportation Research Part C: Emerging Technologies, 1994

Tools for evaluating traffic networks under information supply are a crucial necessity in view of the ATMS/ATIS systems being proposed and implemented around the world as part of Intelligent Vehicle-Highway Systems of the future. This paper presents an evaluation model that incorporates the driver response to information, the traffic flow behavior, and the resulting changes in the characteristics of network paths, into an integrated simulation framework. The model is based on simulating individual vehicle movements according to ...

California Partners For Advanced Transit and Highways, 1998

The contents of this report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the State of California. This report does not constitute a standard, specification, or regulation.

IAEME PUBLICATION, 2014

The two-fluid methodology has been used to compare the traffic quality of service in urban networks. At times the two-fluid parameters Tm and do not provide a clear basis for such comparisons. This is the case, for example, when one network has a lower Tm but a higher n than another network. In such a case, while the first network has a better quality of traffic service during off-peak hours no definitive statement can be made on which network has a better overall quality of service. This study develops a theoretical maximum flow index based on the two-fluid model parameters to be used as a single index to assess the overall quality of traffic service in networks. The proposed maximum flow index is also estimated for sixteen different urban networks around the world for which the two-fluid parameters have been reported in the literature. The proposed index could be viewed as a single quality of traffic service index which captures the effect of all two-fluid network parameters. Using this index, it is then possible to more accurately compare the quality of traffic service among various urban street networks as well as to conduct before/after assessments in the same network following major traffic control or geometric changes

Within the COLOMBO project, modern traffic surveillance and traffic light control algorithms based on data obtained from vehicular communications are developed. An evaluation of existing descriptions of traffic light evaluation show that both, common measurement definitions as well as standardised simulation scenarios are missing. We present a definition of measurement methodology based on earlier projects, namely iTETRIS and FESTA. Additionally, the scenarios under development are presented, including basic, synthetic ones, as well as some that represent real-world networks.

Research in traffic assignment relies largely on experimentation. The outcomes of experiments using different traffic assignment methods on different road network scenarios may vary greatly. It is difficult for the reader to assess the quality of the results without prior knowledge about the difficulty of the road network. In the current work, we propose an approximate metric to characterise the difficulty of network scenarios which takes travellers’ origins and destinations as well as link capacities into account rather than relying on the size of the network. As this metric considers number of overlapping routes between the origins and destinations of the travelles, a higher number in the metric would indicate a higher possibility of congestion in the road network scenario.

Complex Dynamics of Traffic Management, 2009

Assignment (traffic) The allocation of traffic volumes to routes. Arterial A road with two or more intersections. Bandwidth Time interval in an arterial progressive system during which vehicles can travel unimpeded. Controller A device which controls the sequence and duration of indications displayed by traffic signals. Coordination The establishment of a definite timing relationship between adjacent traffic signals. Cycle time The time required for one complete sequence of signal indications. Delay (traffic) The time lost by vehicle(s) due to traffic interference or control devices. Detector (traffic) A device to detect the presence or passage of a vehicle in the roadway. Flow (traffic) The rate at which vehicles cross a given line on the road; the number of vehicles per unit of time. Headway The time interval between successive vehicle crossings of a given line on the road. Intelligent transportation system The addition of information and communications technology to enhance performance of transport infrastructure and of vehicles. Offset The time difference between the start of green at one intersection and the start of green at a subsequent intersection, or with respect to a system time base. Phase The time interval of a cycle time allocated to any combination of movements receiving the right-of-way simultaneously. Performance index/disutility index A numerical quantity used to measure the performance of a traffic in a network in an optimization or a simulation model; also objective function. Platoon A tight group of vehicles traveling along an arterial. Progression A timing plan enabling a platoon to travel unimpeded along an arterial. Saturation flow The rate of flow at which vehicles are discharged from a queue stopped at a signal; the maximum rate of flow on a street. Synchronization A condition under which traffic signals operate with the same cycle time. Volume (traffic) The number of vehicles crossing a line on the road per hour; traffic flow. Definition of the Subject Much of our economic and social life is dependent on communication and transportation systems. Travel in urban networks represents an interaction between the demand for transportation and the supply of transportation means and facilities which includes the vehicles, the road networks,

2013

Undersigned, Tamás Tettamanti, hereby state that this Ph.D. Thesis is my own work wherein I have used only the sources listed in the Bibliography. All parts taken from other works, either in a word for word citation or rewritten keeping the original contents, have been unambiguously marked by a reference to the source.

2011

Quality Control Organisation Date Result v. Cities today face many common transport problems and implement similar urban traffic management solutions, with Intelligent Transport Systems (ITS) playing a prominent role. However, in the absence of a set of widely accepted performance measures and transferable methodologies, it is very difficult for a city to objectively assess the effects of specific applications (policies and technologies) and to make use of lessons learnt from other cities. The aim of this report is to define a common evaluation framework for the performance of traffic management and ITS in the form of a set of Key Performance Indicators (KPIs), and to present guidelines as to its application. The report initially identifies the needs from a performance evaluation framework, as these have been set out by a number of European city transport authorities through a focus group, and describes the development methodology, discussing the issues of goals and objectives, dime...

Advanced Microsystems for Automotive Applications 2010, 2010

V2X communication -communication between vehicles (V2V) and between vehicles and infrastructure (V2I) -promises new methods for traffic management by supplying new data and by opening new ways to inform drivers about the current situation on the roads. Currently, V2X cooperative systems are under development, forced by both the industry and by the European Commission which supports the development as a part of its Intelligent Car Initiative. Within this publication, "iTETRIS", a new system for simulating V2X-based traffic management applications is described which aims on high-quality simulations of large areas. This is achieved by coupling two well-known open source simulators. The sustainability of the project is guaranteed by making the whole also available as an open source tool.

IET Intelligent Transport Systems, 2021

Traffic analysis procedures are becoming more robust over time. However, there is still significant room for improvement both in practitioners' adoption of robust methods and in robustness of the methods themselves. One example of oversimplified practice involves peak hour or 30th highest hour analysis, which fails to capture the impacts of varying demands and operating conditions. To address this limitation, detailed reliability modelling procedures were developed for the Highway Capacity Manual (HCM), but these procedures bring challenging input data and calibration requirements. A new generation of datadriven tools is capable of real-time congestion identification, but their performance measures are only beginning to improve and evolve. Finally, comparing and ranking congested locations (i.e. bottlenecks) on the basis of experience and judgment lacks credibility unless backed by quantitative results. This study discusses the development of new and innovative performance measures for congestion measurement. A case study of ranking eight real-world bottlenecks based on the proposed measures and existing HCM measures produced new insights that could improve both approaches. Ideally, these new insights and methods would be accepted by agencies and/or commercial products for a new level of robustness in congestion measurement. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.