Search

Traffic management policies aim to improve traffic flow by influencing the route choice of drivers, therefore preventing traffic jams in crowded cities. With respect to a system-optimum of the traffic network, drivers might have to make small-scale detours. The aim of this article is to encourage unselfish route choice behaviour in an urban context by informing drivers in advance about the objectives of traffic management. Two studies were conducted: (1) an online survey ( N  = 244) and (2) a driving simulation study ( N  = 48). The first study focussed on the general effect of recommendations for routes with longer travel times (system-optimal routes) when traffic management is explained. Other route choice attributes (travel time, red-light duration, time pressure) were analysed as well. Drivers were randomly confronted with 35 route choice scenarios consisting of a main route with certain red-light duration and an alternative route without. Results showed that the compliance with system-optimal routes is increased by around 10 percentage points when comparing the group with recommendation to the group without. This effect occurred independently of the variation of other route choice attributes. The second study aimed to determine if the compliance can be increased even more if drivers receive in-depth information about traffic management and experience ‘good’ as well as ‘bad’ recommendations in a driving simulator. Results showed no further effect of these manipulations on route choice. Only decision-making times and subjective evaluation were influenced by in-depth information compared to basic information. Altruism was partly correlated with decision-making. This article shows a novel approach to encouraging drivers to select routes with longer travel times for the benefit of the common good. Drivers’ knowledge gap regarding traffic management needs to be closed in order to enhance their understanding of traffic regulations. Finally, results of this research should be transferred to driver models within traffic simulations to estimate the effects on traffic networks. [ABSTRACT FROM AUTHOR]

The transportation demand is rapidly growing in metropolises, resulting in chronic traffic congestions in dense downtown areas. Adaptive traffic signal control as the principle part of intelligent transportation systems has a primary role to effectively reduce traffic congestion by making a real-time adaptation in response to the changing traffic network dynamics. Reinforcement learning (RL) is an effective approach in machine learning that has been applied for designing adaptive traffic signal controllers. One of the most efficient and robust type of RL algorithms are continuous state actor-critic algorithms that have the advantage of fast learning and the ability to generalize to new and unseen traffic conditions. These algorithms are utilized in this paper to design adaptive traffic signal controllers called actor-critic adaptive traffic signal controllers (A-CATs controllers). The contribution of the present work rests on the integration of three threads: (a) showing performance comparisons of both discrete and continuous A-CATs controllers in a traffic network with recurring congestion (24-h traffic demand) in the upper downtown core of Tehran city, (b) analyzing the effects of different traffic disruptions including opportunistic pedestrians crossing, parking lane, non-recurring congestion, and different levels of sensor noise on the performance of A-CATS controllers, and (c) comparing the performance of different function approximators (tile coding and radial basis function) on the learning of A-CATs controllers. To this end, first an agent-based traffic simulation of the study area is carried out. Then six different scenarios are conducted to find the best A-CATs controller that is robust enough against different traffic disruptions. We observe that the A-CATs controller based on radial basis function networks (RBF (5)) outperforms others. This controller is benchmarked against controllers of discrete state Q-learning, Bayesian Q-learning, fixed time and actuated controllers; and the results reveal that it consistently outperforms them. [ABSTRACT FROM AUTHOR]

Perimeter control based on the Macroscopic Fundamental Diagram (MFD) is widely developed for alleviating or postponing congestion in a protected region. Recent studies reveal that traffic conditions might not be improved if the perimeter control strategies are applied to unstable systems where high demand generates heavy and heterogeneously distributed traffic congestion. Therefore, considering stability of the targeted traffic system is essential, for the sake of developing a feasible and then optimal control strategy. This paper sheds light on this direction. It integrates a stability characterization algorithm of MFD system equations into the Model Predictive Control (MPC) scheme, and features respectively an upper and a lower bound of the feasible control inputs, to guarantee system stability. Firstly, the dynamics of traffic heterogeneity and its effect on the MFD are analyzed, using real data from Guangzhou in China. Piecewise affine functions of average flow are proposed to capture traffic heterogeneity in both regional and subregional MFDs. Secondly, stability of a three-state two-region system is investigated via stable equilibrium and surface boundaries analysis. Finally, a three-layer hierarchical control strategy is introduced for the studied two-region heterogeneous urban networks. The first layer of the controller calculates the stable surface boundaries for the given traffic demands and then determines the bounds of control input (split rate). An MPC approach in the second layer is used to solve an optimization problem with two objectives of minimizing total network delay and maximizing network throughput. Heterogeneity among the subregions is minimized in the last layer by implementing simultaneously a subregional perimeter flow control and an internal flow control. The effectiveness and stability of the proposed control approach are verified by comparison with four existing perimeter control strategies. [ABSTRACT FROM AUTHOR]

To reduce disruption to traffic during bridge replacement, accelerated bridge replacement (ABR) methodologies are being developed. One of the ABR methodologies being implemented is slide-in bridge construction (SIBC), which reduces the total duration of traffic disruption to less than one or two weekends. Because the SIBC activities are new, the system response is unknown. Quantification of the loads acting on permanent and temporary structures during the slide operation is required to develop recommendations for standardizing SIBC. With this purpose, substructure movements were monitored during an SIBC project in Michigan, USA, and the forces acting on the substructure during the slide operation were back-calculated. Theoretically, forces develop in the sliding direction because of friction, and in the vertical direction because of superstructure weight. However, the analysis results indicated that a force couple developed due differential friction at the sliding surfaces, and resulted in rotating the superstructure and pushing the substructure in the horizontal direction transverse to the slide. Therefore, it is recommended to include monitoring as a task in the project special provisions until the process is standardized. [ABSTRACT FROM AUTHOR]

Cities are complex systems, where related Human activities are increasingly difficult to explore within. In order to understand urban processes and to gain deeper knowledge about cities, the potential of location-based social networks like Twitter could be used a promising example to explore latent relationships of underlying mobility patterns. In this paper, we therefore present an approach using a geographic self-organizing map (Geo-SOM) to uncover and compare previously unseen patterns from social media and authoritative data. The results, which we validated with Live Traffic Disruption (TIMS) feeds from Transport for London, show that the observed geospatial and temporal patterns between special events ( r = 0.73), traffic incidents ( r = 0.59) and hazard disruptions ( r = 0.41) from TIMS, are strongly correlated with traffic-related, georeferenced tweets. Hence, we conclude that tweets can be used as a proxy indicator to detect collective mobility events and may help to provide stakeholders and decision makers with complementary information on complex mobility processes. [ABSTRACT FROM AUTHOR]

The article offers information on the development of Zone a Traffico Limitato (ZTL), or traffic-limited zone in Italy to reduce automobile congestion and environmental degradation.

Vehicle following has always been a hotspot of research in the transportation system. It can be used in many applications, such as unmanned ground vehicle (UGV) queue marching, traffic congestion relief, automatic driving systems, etc. Trajectory tracking has been the main consideration in previous studies, but the research about following distance is rare. In this paper, a novel vehicle-following model is proposed for independent vehicle following. In the proposed model, multisensor information is fused to promote the detection accuracy. Moreover, a virtual piecewise spline tow-bar is built between the leader vehicle and the follower vehicle. According to the state of virtual towbar, the following speed and heading can be well controlled, to keep a reasonable gap between two vehicles. The proposed vehicle-following model is designed for low speed and minor vehicle spacing case. By using the proposed vehicle-following model, the performance of multplevehicle automatic cruise can be improved, resulting in a steady traffic flow on an express way. Then the stop-and-go waves of congestion can probably be relieved. Simulation and experiment are conducted to validate the efficiency and robustness of the proposed vehicle-following model. [ABSTRACT FROM AUTHOR]

A simple yet efficient traffic flow model, in particular one that describes vehicle longitudinal operational control and further characterizes a traffic flow fundamental diagram, is always desirable. Though many models have been proposed in the past with each having its own merits, research in this area is far from conclusive. This paper contributes a new model, i.e., the longitudinal control model, to the arsenal with a unique set of properties. The model is suited for a variety of transportation applications, among which a concrete example is provided in this paper. [ABSTRACT FROM AUTHOR]

For a predetermined set of an upper bound of link flows, this paper proposes a price-based congestion control scheme for achieving such a restraint target of traffic flow that evolves from day to day. On each day, drivers have to pay a toll selected from a feasible set. The tolls on each day are determined by the link flows and toll charges on the previous day and the predetermined upper bound of link flows. Several properties of the dynamical system model with the control scheme are analyzed, including the invariance of its evolutionary trajectories; the equivalence between its stationary state and user equilibrium under toll charge; the uniqueness, existence, and boundedness of its stationary state; and the convergence of its evolutionary trajectories. A special case of the model and implementation of the control scheme for several alternative targets are also given. Finally, application of the model to a traffic network is demonstrated with a numerical example. The study is helpful for better understanding the mechanism of congestion control under day-to-day traffic flow dynamics. [ABSTRACT FROM AUTHOR]

Graphic route information panels (Grips) provide traffic information by displaying a few distinct colours on simple network topologies. The images that the Grip are able to present are usually limited, as are their corresponding splitting rates. Assessing the effectiveness of these limited splitting rates in alleviating traffic congestion is of practical significance. To this end, this paper considers the simple but typical Grip that presents three colours on a network with two routes. An optimal iterative guidance strategy is taken as the strategy for selecting splitting rates. All possible splitting rates that the Grip can deliver are enumerated in deterministic and stochastic simulation scenarios, in which drivers completely follow route guidance and subsequently choose a route based on a probability. The results are analysed and compared, and further general conclusions are made. A number of investigations are addressed including a basic requirement for the Grip's capacity to alleviate congestion, stability of the traffic influenced by the guidance information, impact of the uncertainty of drivers' understanding of the information, and so on. The results are useful in the assessment and proposal of practical route guidance strategies as well as when educating drivers to understand better the guidance information provided by the Grip. [ABSTRACT FROM AUTHOR]

Over the past few decades, several active traffic control methods have been proposed to improve freeway efficiency at bottleneck locations. Variable speed limit (VSL) is one of these effective controls. Previous studies have evaluated VSL control, but primarily during recurrent congestion only. This study focuses on evaluating the performance of VSL control for both recurrent and non-recurrent congestion. To assess the effectiveness of a previously proposed VSL control in a real-world situation, this study has three evaluation objectives: (1) examine the control performance when recurrent and (or) non-recurrent congestion occurs; (2) assess the effectiveness of the control when a queue encounters the VSL sign; and (3) consider the impact of system detection delay in VSL control. Comparative experiments for Whitemud Drive in Edmonton, Alberta, Canada, are simulated in the VISSIM platform, and traffic performance is compared among scenarios with and without control. The simulation results show that VSL improves mobility for both recurrent and non-recurrent congestion. The VSL control reduces total travel time, and improves total travel distance and total flow. Furthermore, it slows down the shockwave propagation speed, improves the average speed on most of the freeway segments, and reduces the duration of traffic recovery. [ABSTRACT FROM AUTHOR]

In this study, dynamic traffic control strategies, namely dynamic ramp metering and dynamic speed limit control, have been examined through microscopic traffic simulation based on site measurements. In this context, the traffic flow data at a particular highway intersection have been analyzed to determine the pattern of the traffic. Then, the traffic model has been built in a traffic micro-simulation software and calibrated with the field data. The foci of the study are to measure the efficiency of the dynamic traffic control strategies and to compare it with the uncontrolled case considering various performance indicators such as total travel time, average delay time per vehicle, and average number of stops per vehicle. For the dynamic ramp metering strategies, the ALINEA (Asservissement Lineaire d'Entree Autoroutiere - French for Linear Utilization for Highway Entrances) control algorithm is implemented with different fixed-time cycle lengths. It has been observed that various ramp metering implementations decreased the average delay time per vehicle up to 30%. The dynamic speed limit control strategies are set according to the occupancy rates that are measured at the bottleneck downstream. The examined speed limit control strategies decreased the average delay time per vehicle to around 7%. The results also revealed that the implemented dynamic traffic control strategies help alleviate congestion by increasing the capacity of the bottleneck section. [ABSTRACT FROM AUTHOR]

Traffic speed variance is defined as a measure of the dispersion of space mean speeds among drivers. Empirical speed-density observations exhibit a structured traffic speed variance, which has been found to be associated to the roadway crash rate, the fatality rate, and travel time variability. The objective of this paper is to propose a generalized traffic speed variance function to describe this structured variance. The proposed speed variance function is a response of the speed-density curve with two additional parameters. The estimation of the model parameters in the proposed traffic speed variance function can be carried out through an iterative nonlinear least-square algorithm (i.e., LevenbergMarquardt). A series of logistic speed-density curve with varying parameters are used in the proposed traffic speed variance function with different levels of performance. The proposed traffic speed variance model can potentially help to unveil the underlying mechanism of empirical traffic phenomenon such as spontaneous congestion or capacity reduction. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents several possibilities of using tunnels to solve traffic problems in the area of the Polish mountains. So far, in contrast to other countries in Europe and the World in Poland this kind of solution are benefited reluctantly. However, in the longer term, tunnels construction in conjunction with flyovers are cheaper solutions, safer and considerably reduce the negative impact of transport on the environment. The situation is beginning to change and recently in Poland increases interest in the underground construction, particularly tunnels in mountainous areas are observed. This paper describes the newly built tunnel in Laliki and planned to build tunnels in the area of Lubień, Poronin, Krynica-Zdrój, Jordanów and Węgierska Górka. [ABSTRACT FROM AUTHOR]

Over the last decades, many cities have experienced a rapid increase in automobile as a result of continuous population growth and pursuing better quality of living. Vehicle growth and limited space of cities bring a problem of traffic congestion. In coping with this problem, various traffic management measures are being applied worldwide. Transport pricing policies are demand management measures of transportation system to reduce traffic congestion. Like many other cities, Hong Kong is also applying various transport pricing policies for relieving congestion resulted from a steady vehicle growth. Present paper aims to explain different forms and the impacts of transport pricing techniques in Hong Kong. So, the main aim of this paper is to explore the impacts of transport pricing techniques in Hong Kong. Literature review and case study are the main source of information of this study. In this paper, after introductory section, some international experiences of transport pricing policy are described and after that various transport pricing policies in Hong Kong presented. After describing various transport pricing policies in Hong Kong their impacts are asserted. This paper ends with a concluding remarks of Electronic Road Pricing (ERP) can be an effective solution for long term success but the government need to do adequate campaigns to gain the public support in favor of ERP. [ABSTRACT FROM AUTHOR]

Mass evacuations of urbanized areas can be expected to generate traffic demand significantly in excess of routine daily travel conditions. Depending on the nature of the hazard and the population characteristics within the threat area, the elevated demand conditions may last for several days and can impact thousands of miles of roads. This paper presents the results of a project to evaluate the impact of a transit bus-based evacuation on the operation of a regional road network during a mass evacuation. In the project, the TRANSIMS agent-based simulation system was used to model the Citizen-Assisted Evacuation Plan (CAEP) for the City of New Orleans within the context of a general evacuation. Regional plans developed by Louisiana officials to support the evacuation of low-mobility individuals when under threat of hurricanes were used to code the model. However, because these plans have yet to be fully implemented, their benefits, effect on the overall evacuation operation, and the adequacy of the service they will provide has not been evaluated. In this the operational traffic characteristics of the busses and other vehicles involved in the evacuation operation were simulated under a range of conditions. The results showed that while the CAEP busses were able to increase the total number of people evacuated from the threat area, the additional vehicles had a minimal impact when they were routed exclusively to arterial evacuation routes. However, when bussed were routed to more heavily utilized freeways, travel delays increased and congestion queues increased by about 50 percent. [ABSTRACT FROM AUTHOR]

End-to-end traffic delay control within actual communication networks represents a very important goal for an administrator, due to the direct influence on service quality of service level, which is delivered to users. The difficulty of a maximal end-to-end delay prediction is related especially to the random traffic behaviour within waiting queues belonging to network nodes. The aim of this paper is to present a delay control proposal for the data traffic within a queue wherein is activated a weighted random early detection (WRED) congestion avoidance mechanism. [ABSTRACT FROM AUTHOR]

The result of four transportation demand management (TDM) implementations in three major traffic concentration periods of 2007–2008 with discounts on tolls for electronic toll collection vehicles, as intended to mitigate traffic congestion in an uninterrupted flow section of the Tomei Expressway is described. As a result of the TDM implementation, the peak-hour demand is estimated to decrease by 2–5%. Although traffic congestion continues to occur, partly because of the increased daily traffic demand and the insufficient shift of traffic demand from peak hours to off-peak hours, it is estimated that the total delay is reduced by 27–35% relative to the case in which there is no TDM implementation, resulting in a reduction in CO2 emission of 6–8% and 65 ton-c for the four TDM implementations. It is seen that the average shift rate of traffic increases with the amount of the toll discount. Apparently, it is also difficult to expect a high shift rate of traffic if the amount of the discount is less than approximately 1000 yen. The estimated midpoint arc elasticity of the toll-discount time period ranges from -0.30 to -0.72, depending upon the holiday type and the details of the discount time period. [ABSTRACT FROM AUTHOR]

The article presents a study that investigates the significance of the South Snohomish Regional Transit Signal Priority (SS-RTSP) system in Washington. It cites that simulation models and field data served as variables in the evaluation of traffic operations and transit systems as SS-RTSP is used to reduce traffic congestion. Different areas are given value in assessing transit signal priority (TSP) such as vehicle delays. It notes that SS-RTSP has a significant impact on transit vehicles.

Abstract: The “Stockholm Trial” involved a road pricing system to improve the air quality and reduce traffic congestion. The test period of the trial was January 3–July 31, 2006. Vehicles travelling into and out of the charge cordon were charged for every passage during weekdays. The amount due varied during the day and was highest during rush hours (20 SEK = 2.2 EUR, maximum 60 SEK per day). Based on measured and modelled changes in road traffic it was estimated that this system resulted in a 15% reduction in total road use within the charged cordon. Total traffic emissions in this area of NO x and PM10 fell by 8.5% and 13%, respectively. Air quality dispersion modelling was applied to assess the effect of the emission reductions on ambient concentrations and population exposure. For the situations with and without the trial, meteorological conditions and other emissions than from road traffic were kept the same. The calculations show that, with a permanent congestion tax system like the Stockholm Trial, the annual average NO x concentrations would be lower by up to 12% along the most densely trafficked streets. PM10 concentrations would be up to 7% lower. The limit values for both PM10 and NO2 would still be exceeded along the most densely trafficked streets. The total population exposure of NO x in Greater Stockholm (35 × 35 km with 1.44 million people) is estimated to decrease with a rather modest 0.23 μg m−3. However, based on a long-term epidemiological study, that found an increased mortality risk of 8% per 10 μg m−3 NO x , it is estimated that 27 premature deaths would be avoided every year. According to life-table analysis this would correspond to 206 years of life gained over 10 years per 100 000 people following the trial if the effects on exposures would persist. The effect on mortality is attributed to road traffic emissions (likely vehicle exhaust particles); NO x is merely regarded as an indicator of traffic exposure. This is only the tip of the ice-berg since reductions are expected in both respiratory and cardiovascular morbidity. This study demonstrates the importance of not only assessing the effects on air quality limit values, but also to make quantitative estimates of health impacts, in order to justify actions to reduce air pollution. [Copyright &y& Elsevier]

The article presents the author's insights on being the recipient of the 2009 Theodore M. Matson Memorial Award. He states that his career has been benefited from others' reluctance to push the message on how important transportation is to the economy and to people's lives. He discusses traffic congestion which is an issue that affects research engineers. He also tackles the value of transportation and suggests to reduce the congestion through projects and policies of agencies and individuals.

The introduction of a fee to manage mobility is widely used by many governments to mitigate the social costs. These costs occur when the demand exceed the road capacity. Moreover, in order to reduce congestion, the fee can generate revenues for strengthening public transport, create infrastructure and implement innovations that improve the mobility of the inhabitants. This article aims to identify the different theoretical, technological and practical aspects also including the opponents of this policy that implies the adoption of this type of solutions to manage the mobility problems in congested urban roads. [ABSTRACT FROM AUTHOR]

Wireless communications for intelligent transportation systems promise to be a key technology for avoiding the traffic nightmares of today - accidents and traffic jams. But there is one major challenge to be overcome before such a cooperative system can be put into place: standardization. This article provides an overview of the technical developments in Europe and their convergence toward a set of European standards. We address the current state of the standardization activities and the potential scenarios and use cases, and we describe the fundamental concepts of a European communication architecture for cooperative systems. [ABSTRACT FROM AUTHOR]

In this article, the author conducted preliminary research on public transportation systems in four countries to aid in the development of a Comparative Public Administration course. The four countries (Canada, Mexico, the United Kingdom and South Africa) each offer unique challenges regarding mass transit. Increasing investment in mass public transit is vital to controlling urban pollution, reducing dependency on foreign oil, and reducing traffic congestion. Additionally, the article looks at the use of sabbaticals as a tool for researchers, both as a method for revitalizing professionals in the academic world and as a way to encourage research on subjects which may be less well-funded. The research will be incorporated into the course as an example of the kinds of research the students can do themselves, regardless of area of interest. [ABSTRACT FROM AUTHOR]

With the recent increase in the deployment of ITS technologies in urban areas throughout the world, traffic management centers have the ability to obtain and archive large amounts of data on the traffic system. These data can be used to estimate current conditions and predict future conditions on the roadway network. A general solution methodology for identifying the optimal aggregation interval sizes for four scenarios is proposed in this article: (1) link travel time estimation, (2) corridor/route travel time estimation, (3) link travel time forecasting, and (4) corridor/route travel time forecasting. The methodology explicitly considers traffic dynamics and frequency of observations. A formulation based on mean square error (MSE) is developed for each of the scenarios and interpreted from a traffic flow perspective. The methodology for estimating the optimal aggregation size is based on (1) the tradeoff between the estimated mean square error of prediction and the variance of the predictor, (2) the differences between estimation and forecasting, and (3) the direct consideration of the correlation between link travel time for corridor/route estimation and forecasting. The proposed methods are demonstrated using travel time data from Houston, Texas, that were collected as part of the automatic vehicle identification (AVI) system of the Houston Transtar system. It was found that the optimal aggregation size is a function of the application and traffic condition. [ABSTRACT FROM AUTHOR]

The article discusses the use of genetic algorithms, which are metaheuristic strategies used in problem solving, to design road-network models for urban transportation. The design of transport networks are considered an optimization problem, so efficient transport models are based on supply and demand and on planning constraints and variables. Topics include: the assignment of private transport within cities using automated methods; the three phases of transport demand; and explanations for the trip assignment model, chromosomes in the connected graph, the quality evaluation function, and a roulette selection strategy used in genetic operations. A road network is designed for Los Angeles City, Chile that is based on population statistics in the years 2000 and 2010.

Based on the optimal velocity models, an extended model is proposed, in which multi-velocity-direrence ahead is taken into consideration. The damping effect of the multi-velocity-direrence ahead has been investigated by means of analytical and numerical methods. Results indicate that the multi-velocity-direrence leads to the enhancement of stability of traffic flow, suppression of the emergence of traffic jamming, and reduction of the energy consumption. [ABSTRACT FROM AUTHOR]

The article analyzes traffic signal timing split optimization methods to address congestion. According to the author, the goal of the methods is to review the basis of the split optimization objective functions. The author also discusses the inherent problems related with traditional approaches to develop optimum timings and the comparative results of a simple controlled experiment.

The introduction of widespread road pricing is being considered in the UK and abroad as a means to allocate scarce road space. By looking at the economic costs and benefits of both national and local road pricing schemes, this paper seeks to examine how widely charging should be implemented. [ABSTRACT FROM AUTHOR]

The article focuses on the consideration of unconventional remedies to traffic congestion at the Kent State University in Ohio. Such consideration serves as a part of the university's strategic plan to address the information related to the patterns and causes of congestion. Students, faculty, and staff at the university are found to be unready to change their transportation and parking behavior in appreciable way. While students regularly complain about the limited parking and traffic congestion, solutions to such issues are found to have been sought by the university prior to becoming untenable. Since university problems are found to affect the surrounding community, cooperation is required by increasing roadway capacity and reducing demand.

In urban transportation planning, it has become critical (1) to determine the travel time of a traveler and how it is affected by congestion, and (2) to understand how traffic distributes in a transportation network. In the first part of this paper, we derive an analytical function of travel time, based on the theory of kinematic waves. This travel-time function integrates the traffic dynamics as well as the effects of shocks. Numerical examples demonstrate the quality of the analytical function, in comparison with simulated travel times. In the second part of this paper, we incorporate the travel-time model within a dynamic user equilibrium (DUE) setting. We prove that the travel-time function is continuous and strictly monotone if the flow varies smoothly. We illustrate how the model applies to solve a large network assignment problem through a numerical example. [ABSTRACT FROM AUTHOR]

Advanced Traveler Information Systems (ATIS) provide travelers with real time traffic information to optimize their travel choices. The objective of this paper is to model drivers' diversion from their normal routes in the provision of ATIS. Five different scenarios of traffic information are used. Generalized Estimating Equations (GEE) framework with repeated observations and binomial probit link function is introduced and implemented. GEE with four different correlation structures including the independent case are developed and compared with each other and with regular Maximum Likelihood Estimation (MLE). A travel simulator was used. Sixty-five subjects have traveled 10 simulated trial days each on a 40-link realistic network with real historical congestion levels. The results showed that providing traffic information increases the probability of drivers' diversion from their normal routes. Adding advice to the pre-trip and/or en-route information encourages drivers to divert. Providing en-route in addition to the pre-trip information with or without advice increases the diversion probability. High travel time on the normal route and less travel time on the diverted route increase the probability of diversion. High-educated drivers are less likely to divert. Expressway users are more likely to divert from their normal routes under ATIS. Drivers' familiarity with the device that provides the information and high number of traffic signals on the normal route increase the diversion probability. [ABSTRACT FROM AUTHOR]

Points out that electronic charging technology has matured to the point where it can be used effectively and relatively cheaply on both urban and inter-urban roads in order to combat traffic congestion. Technical options; Microwave DSRC (Dedicated Short-Range Communications); Cameras and the Automatic Number-Plate Recognition (ANPR) system; Satellite-based Global Positioning System; Road pricing. INSET: USEFUL WEB LINKS.

For a congestion-relief tunnel to fulfill its purpose, it must keep its traffic moving. To do so in a high-demand area, it is necessary to limit access to the maximum number of vehicles per hour consistent with smoothly flowing traffic. The most feasible way to do this is to vary the level of toll in accordance with the varying demand at different types of day. This form of road pricing has come to be known as congestion pricing. Congestion-relief toll tunnels appear to be economically and technically feasible in selected urban areas. The remaining questions to be addressed are the legal and political feasibility of this concept in the U.S. Congestion-priced toll tunnels will be self-financing via user charges, operate in a low-emission, constant speed mode, and divert significant traffic off existing urban freeways and streets, reducing noise and street-level emissions.

Estimates the potential benefits of new traffic control and management systems in comparing the total cost incurred in equilibrium. Objective of federal highway policies; Dynamics of traffic congestion; Comparison of dynamic system optimum and user equilibrium traffic flow patterns; Equilibrium patterns on general networks.

Presents the results of a quantitative analysis of driver recruitability conducted to aid in the design of recruitment procedures for Advanced Driver and Vehicle Advisory Navigation Concept (ADVANCE). Results and implications for the recruitment effort both in terms of recruiting drivers for participation in the demonstration and specifying the operational details of the field test.

This paper presents a method for applying HOV lanes to the Taiwan freeway system. The purpose is to develop guidelines for designating alternative HOV lanes on existing freeways. Simulation results suggest that introducing HOV facilities would significantly improve traffic delays for short and long term steady states, especially during peak hour traffic flow. To ensure the success of the proposed HOV facilities, special attention should be devoted to public awareness and communication, as well as to related planning, education and enforcement issues. [ABSTRACT FROM AUTHOR]

One of the suggested techniques for reducing peak period traffic congestion is to flex work hours. If one is to predict the effect this work hour change shall have on the congestion, it is essential to understand how the peak traffic demand develops. However, there seem to be no existing theories explaining this process. In this paper, therefore, a mechanism by which commuters select their departure time from home is suggested and, based on this, a method is proposed for predicting the temporal distribution of traffic demand during the peak period. This should lead to the understanding of the effects of flexed work hours on the congestion. The model developed in this paper is based on the assumption that the commuters wish to arrive at work at a particular time without being delayed for too long in the system. A commuter therefore attaches cost to delays and also to early and late arrivals at work. This model proposes an iterative procedure by which to obtain the distribution of a commuter's departure time from home, assuming that he tries to minimize the total cost. [ABSTRACT FROM AUTHOR]