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This study aims to make full use of the advantages of connected and autonomous vehicles (CAVs) and dedicated CAV lanes to ensure all CAVs can pass intersections without stopping.

The authors developed a signal coordination model for arteries with dedicated CAV lanes by using mixed integer linear programming. CAV non-stop constraints are proposed to adapt to the characteristics of CAVs. As it is a continuous problem, various situations that CAVs arrive at intersections are analyzed. The rules are discovered to simplify the problem by discretization method.

A case study is conducted via SUMO traffic simulation program. The results show that the efficiency of CAVs can be improved significantly both in high-volume scenario and medium-volume scenario with the plan optimized by the model proposed in this paper. At the same time, the progression efficiency of regular vehicles is not affected significantly. It is indicated that full-scale benefits of dedicated CAV lanes can only be achieved with signal coordination plans considering CAV characteristics.

To the best of the authors’ knowledge, this is the first research that develops a signal coordination model for arteries with dedicated CAV lanes.

Purpose – Urban and suburban arterials carry a large share of urban traffic and contend with a relatively large proportion of transport network crashes. Road crashes and their consequent societal costs diminish the sustainability of transportation systems, highlighting the need to identify road safety problems and their corresponding solutions. This chapter briefly outlines problems and solutions associated with crash risk on urban and suburban arterials. In addition, this chapter studies and discusses several safety countermeasures – ranging from local treatments to integral frameworks – and their effectiveness on improving traffic safety of urban and suburban arterials.

Approach – Crash occurrence on urban and suburban arterials is affected by numerous contributing factors. This chapter pays attention primarily to the effects of traffic characteristics and road design features. In this regard, several pertinent variables which have been extensively examined in the literature are reviewed and their contributions to the safety of urban and suburban arterials are discussed.

Findings – A review of the literature identifies a number of variables as influential factors of crashes on urban and suburban arterials. Although the associations of some variables (e.g., traffic volume) are consistent with expectations, others (e.g., lane width and speed) show mixed and sometimes counterintuitive results. These findings signify that additional research is needed to reveal the correct functional form and magnitude of these relationships.

Practical implications – The results show that while the general direction and magnitude of effects of some engineering and management-related treatments are known, additional research is needed to consolidate the impact and effectiveness of integrated approaches.

Urban networks are usually divided into several open or closed sub‐networks. Signal coordination has been recognized as one of the most efficient methods of controlling sub‐networks that have independently optimized timing plans. However, coordinating adjacent intersections in a network is a basic prerequisite to optimizing signal‐timing plans for sub‐networks. This paper aims to develop a linear model to support decisions regarding coordination of adjacent signals.

This paper aims to develop a linear model to support decisions regarding coordination of adjacent signals. The tests of this model which using the field data differ from those for calibration from various roadways, indicating that the model has transferability. Evaluations using microscopic simulation show that the model can objectively determine whether or not to interconnect adjacent signals depending on various traffic demands.

The model was calibrated by stepwise regression analysis with a total of 195 field samples. This model consists of the dependent variable critical block length (CL) between adjacent intersections, and the independent variables original platoon size (OPS) and platoon completeness ratio (PCR). The calibrated model is shown as following: CL = 689.97 + 6.86 OPS−7.15 PCR.

The proposed model appears to be a viable solution for determining whether to coordinate adjacent signals according to various traffic demands for variously configured roadways. The model shows that a larger OPS or a smaller PCR implies a larger CL. The model also indicates that adjacent signals must be interconnected if they are separated by 690 meters or less. The results also suggest that OPS from 10 to 30 fully disperse at about 800 meters downstream of a stop line. The results support the CL for effectively coordinating adjacent signals, similar to that recommended in the Manual on Uniform Traffic Control Devices. These results may be useful for the effective management of traffic signal networks.

With the development of the modern economy, vehicles are no longer a luxury for people, which greatly facilitate people’s daily life, but at the same time bring traffic congestion. How to relieve traffic congestion and improve its capacity is a hot research area. This paper aims to propose a new simulation framework for crowd transportations to ease traffic congestion.

This paper establishes related simulation models such as vehicles, traffic lights and advisers. Then the paper describes their relationships, gives their interaction mechanism and solidifies the above into a software implementation framework.

This paper proposes a simulation framework for crowd transportations.

In this framework, traffic lights are used as a control method to control the road network and road conditions are used as an Affecter to influence individual behavior. The vehicle passing rate is defined by the correlation between endowment and the start time of the traffic lights. In this framework, members are related, dynamically adjusted according to road conditions and dynamically optimized member decisions. The optimal path is dynamic and real-time adjustments are made for each step forward. It is different from the traditional optimal path in which there is only one fixed one and it is different from the macroscopic optimal path that does not exist.

Due to the conflicts between left turn traffic and opposite straight-going traffic in urban traffic network, some of the traffic lanes cannot be used to discharge vehicles during its green phases and the intersection capacity can be greatly reduced. This study/paper aims to reduce the effect of conflicts and increase its capacity through the reasonable pre-signal phase time with the exchangeable lanes.

This paper took into consideration various influence factors to intersection capacity and formulated the capacity optimization model based on 0-1 mixed-integer programming model. This model is efficiently solved by standard branch-and-bound algorithms.

The authors took an intersection as an example and solved the optimal signal timing and entrance lane capacity via this model. Then, simulations were carried out to verify the effect of the exchangeable lanes strategy of this intersection through the simulation software VISSIM and take the traffic volume and delay as outputs, which indicated that this model has better performance.

The front-end control strategy can not only exploit the full potential of the intersection but also significantly improve the operational efficiency of the intersection. It plays a positive role in improving urban intersection congestion.

Under deteriorating conditions of travelling in urban areas, especially city centers, prioritization of public transport is one of the main ways of its enhancing. In developed countries sophisticated control traffic systems are being implemented while in developing countries such solutions due to implementation cost are very rare. The purpose of this paper is to assess public transport operational effectiveness under diverse operational schemes present in two similar in size and traffic characteristics cities. The assessment is based on average journey times and speeds during peak and off peak hours.

The methodology includes measurements and estimates of bus rides through in-field measurements in Edinburgh, UK and in Bialystok, Poland. In-field evaluations have been conducted using average speed and travel times. The data were collected by utilizing a portable GPS data logger that allowed monitoring and recording bus position along tested streets in one second intervals. Traffic optimization in Edinburgh is provided by separated bus lanes and control urban traffic system while in Bialystok the only prioritization is supported by bus lanes. The research areas in Edinburgh and in Bialystok covered streets in city centers and adjacent districts.

The findings show large operational potential in developing separated bus lanes in city centers of developing countries when due to cost they cannot afford implementing advanced ITS solutions. The introduction of bus lanes should be proceeded even at the expense of individual users. It has been found that well developed road network in city center with separated bus lanes can provide operating speed at comparable levels to speed of buses operating along lower volume corridors.

The comparison of bus lanes working under different traffic management conditions was carried out. Conducted analyses showed great potential of proper planning strategy of road network development toward the improvement of public transport performance.