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Due to recent advancements in connected and autonomous vehicles (CAVs), freeway traffic control (FTC) has become a trendy area of research. Combining CAVs and control measures has opened more efficient traffic flow possibilities. However, while there is extensive research on how traffic control and CAVs can enhance traffic flow performance, their safety benefits should be evaluated more comprehensively. It is challenging to distinguish their contributions to traffic flow safety. Studies on the safety of CAVs in traffic flow indicate that traffic flow safety improves with higher market penetration rates (MPR) of CAVs. However, this finding only sometimes aligns with the traffic flow performance effects of CAVs on freeways. This paper introduces a framework for assessing the safety effects of FTC strategies in mixed traffic scenarios involving human-driven vehicles and CAVs. The proposed framework is tested through a microsimulation-based case study in Istanbul, Turkey. The results show that, despite varying MPRs, the safety effects of CAVs and FTC methods do not consistently reduce the number of conflicts in the traffic flow context. [ABSTRACT FROM AUTHOR]

The increased number of city networks such as 100 Resilient Cities, proves the importance of making cities disaster resilient. The major difficulty on this trajectory is the interrelated components in urban systems that influence each other and increase uncertainty in the risk assessment and management. This study analyses the potential disruptions that impact traffic control with the help of multi-hazard risk assessment for the historical peninsula of the city of Istanbul. 3D model is created for the visualisation of disaster risk to support the communication of the causes of such potential disruptions. The additive normalization indicator-based approach is used to assess the socioeconomic, road and systemic vulnerability and risk. Besides, the EMS-98 Macroseismic method is applied to determine the building vulnerability and damage grades. The results show that the socioeconomic vulnerability is high to very high which is likely to contribute to traffic congestions and communication issues. In addition, most of the buildings are expected to be 'very heavily damaged'. So, while roads have low risk to damage, there is high risk for road blockages in the narrow streets of the case study area. The application of 3D models improves the recognition of buildings and the identification of the causes of road blockages. [ABSTRACT FROM AUTHOR]

Bus rapid transit maximises the capacity of mass transit serviced by buses. Dedicated transit ways, specially designed stations and buses, customised fare-collection methods and dispatch management are instrumental to achieve this capacity maximisation. The increased mass transit capacity provided by bus rapid transit services (BRTSs) is comparable to transit capacities provided by urban rail transit systems. Due to their perceived simplicity of implementation and implementation costs, the adoption of bus rapid transit is favoured by municipalities for mass transit in a number of cities around the world. BRTSs provide a fast and effective solution to increased transit demand that surpasses the limits of ordinary bus services in mixed traffic. However, BRTSs have inherent limitations in terms of control, capacity, safety, serviceability and urban well-being. These limitations result in significant service failures and reduced safety. This study raises some concerns and discusses some aspects of bus rapid transit with regard to its safety and serviceability. The study then investigates the types and occurrences of adverse events such as accidents, incidents and service failures experienced in the BRTS in Istanbul since its inauguration and assesses the adverse events that have occurred. [ABSTRACT FROM AUTHOR]

Many types of systems that seek solutions to cities' mobility issues, such as traffic congestion and accidents, have recently been proposed worldwide. A bottleneck, which is defined as an occurrence of congestion at a highway segment, is one of the major causes of citizens' discontent in cities. Bottlenecks cause a decrease in vehicles' speeds, creating negative effects on the capacity of the highway segments and traffic jams. It is also an important research domain in traffic engineering that causes delays in road traffic. Within the concept of Intelligent Transportation System (ITS), this paper presents a method for investigating road state, speed, and road bottlenecks, without any extra investment and permissions for General Data Protection Regulation (GDPR) compliance procedures. The proposed analysis uses publicly available data of bus stations and buses. The analysis is performed on a chosen route as a numerical example, and the calculated speeds are illustrated on a map. [ABSTRACT FROM AUTHOR]

Historical cities around the world have serious traffic congestions due to old infrastructure and urbanization. To mitigate traffic problems in such cities, infrastructure investments are channeled to tunnels, bridges, and highways. The solution becomes more complicated as the city centers are expected to become fully pedestrian-friendly as a European Union target for 2050. Any modification to the city transport network will lead to changes in traffic density patterns. Investment decisions become more pronounced as the speed of urbanization increases. However, this decision-making processes in urban transport networks pose a serious risk to city managers as wrong decisions are expensive and will not solve the problem. This paper proposes a practical, cost-effective model to assist decision makers by providing them with estimated changes in the traffic patterns due to the addition of new roads to existing infrastructure. The study adopts the Extreme Gradient Boosting (XGboost) which is a tree-based algorithm that provides 85% accuracy for estimating the traffic patterns in Istanbul, the city with the highest traffic volume in the world. The proposed model is a static model that allows city managers to perform efficient analyses between projects that involves changes to the city's transport network. • The study includes a traffic control model developed for a 6104 km complex network. • The study provides a productivity analysis for long-term road infrastructure investments. • The study provides an important tool for decision makers in pedestrian friendliness studies. • The study provided an important feature selection for a static traffic forecast. • The study created an application for a congested city with the most severe traffic problem. [ABSTRACT FROM AUTHOR]