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GIS models are currently available for a broad range of applications in mobility planning. However, it is not known how widespread the current use of GIS models is among European urban mobility planners, nor what their user experiences and needs are. There is therefore a risk that the development of GIS models for urban mobility planning will be mainly driven by technical possibilities and data availability rather than by the needs of the prospective users. To inform model developers and ensure a good match between model options and user needs, we conducted a survey investigating the current application of GIS models in urban mobility planning practice in Europe as well as model data availability and the needs and priorities of European mobility planners regarding GIS models. We received 51 valid responses from the transport departments of 42 cities from 21 European countries. For developers of GIS-based traffic models, the findings indicate that in Europe there is scope for wider adoption and further improvement. The models currently used are considered useful to support urban mobility planning, but more than 60% of the surveyed cities do not yet use them. Increased user-friendliness, in particular for non-experts, appears important to promote wider adoption. Availability of non-traditional types of data, such as real-time data or data at neighborhood level, is still limited in most cities, but this may rapidly change. Finally, there is also considerable interest in traffic models that integrate social and environmental aspects. [ABSTRACT FROM AUTHOR]

Highlights • A novel traffic management strategy in automated driving environments is proposed. • A method to adjust the driving aggressiveness of automated vehicles (AV) is developed. • The proposed methodology is to maximize the performance of mixed traffic conditions. • VISSIM simulations are conducted to investigate the feasibility of the proposed methodology. Abstract The advancement of vehicular technologies for automated driving will lead to a mixed traffic flow that depends on the interaction between automated vehicles (AVs) and manually driven vehicles (MVs) because the market penetration rate (MPR) of AVs will gradually increase over time. Because automated driving environments provide us with a valuable opportunity for controlling individual vehicle operation, a strategic policy for managing AVs operation is expected to enhance the performance of the traffic stream. Therefore, the operation of AVs needs to be properly determined to cope with various traffic and road conditions and thereby facilitate smooth and effective vehicle interactions. This study proposed a novel traffic management strategy in automated driving environments by adjusting the driving aggressiveness of AV operation, defined as automated driving aggressiveness (AuDA). VISSIM microscopic simulation experiments were conducted to derive the proper AuDAs to enhance both the traffic safety and the mobility performance. Traffic conflict rates and average travel speeds were used as indicators for the performance of safety and operations. While conducting the simulations, the level of service (LOS) and MPR of the AVs were also considered. In addition, the relationship between key variables for adaptive cruise control (ACC) operations and AuDA policies was explored to better support the understanding of how the proposed methodology works in practice. Promising results showed that the proposed methodology would be effective in optimizing the performance of mixed traffic conditions. Furthermore, the outcome will be valuable in developing various policies and guidelines to manage the operation of AV in automated driving environments. [ABSTRACT FROM AUTHOR]

The rapid increase in private car use in large metropolitan areas has led to irrational travel mode splits and severe traffic problems. Traffic demand management (TDM) is an effective policy to achieve a more sustainable development of traffic systems. This study analyzes the relationships between TDM policy, mode split, and travel mode choice using Stackelberg game theory. Then, using 0-1 programming, it establishes a combination of TDM policy instruments that can achieve a more sustainable mode split in a city and provides a case study in China. The method presented in this research has strong theoretical implications for TDM policymakers. [ABSTRACT FROM AUTHOR]

This study uses repeated cross-sections of individual level crash data to study the effectiveness of motorcycle helmet legislation. Results suggest that motorcycle helmet laws reduce average individual fatality risks by 20.5%. From a policy standpoint, large states such as Florida and Texas can reduce annual motorcycle fatalities by an average 100 deaths through reinstating universal helmet laws. Valuing these fatality reductions at the U.S. DOT suggested $9.4 million value of a statistical life yields aggregate annual state benefits of approximately $940 million. The effectiveness of helmet legislation can be attributed to the technological efficacy of helmets as well as enhancing behavior in the form of reduced risk taking among motorcyclists. Specifically, motorcyclists who use helmets in order to comply with mandatory helmet laws are 29.8% less likely to receive a traffic citation for risky driving behavior (speeding, alcohol, etc.), travel at a 6 mph lower average speed, and have a 47.4% reduction in the probability of “severely” damaging their motorcycle in a crash. [ABSTRACT FROM AUTHOR]

The attitude of the comprehensive inspection vehicle is one of the important factors that affect the accuracy of the inspection of metro line infrastructure, meanwhile the metro environment restricts the employment of common attitude determination methods. A new method of attitude determination is presented in this paper, which takes the track as reference and employs non-contact measurement to acquire the track profile simulta-neously. By registration of measurement track profile and the standard track profile, the relative position between the vehicle and the track reference can be calculated; and the instantaneous attitude of the vehicle can be determined by the matrix inverse calculation. The performance of the method is verified by an experiment using the road-rail comprehensive inspection vehicle. [ABSTRACT FROM AUTHOR]

The major aim of this study was to assess the overall situation of public transport services in Oman, and to suggest some strategies and tactics to ensure a successful transportation system. The study followed a multifaceted research approach involving the key stakeholders whose diverse opinions were taken into account in the development of an effective public transport system in Oman. This study was conducted in four phases which included (i) a review of public transport (ii) a survey of 2000 respondents, (iii) individual interviews, and (iv) discussions with the key officials from the regulating authorities, transport operators, and business sector. A mixed method approach was used in the analyses. The information obtained from the four phases was analyzed using the PESTEL framework to arrive at the conclusions and recommendations. Whilst a wide range of factors was examined in the research, this paper specifically reports the findings pertaining to the strategic actions, derived from the PESTEL framework. The study finds that people have little experience of using public transport in Oman. The introduction of a public transport system has taken an unusually long time and there is a growing need for public transport in Oman to stimulate economic development, increase road safety, and to combat traffic congestion and environmental problems. The government of Oman needs to put more effort into looking at a range of policy issues related to public transport such as public-private partnership, regulation of different modes of transport, benchmarking the best practices, and economic policies such as diversification and taxation. The study recommends the development of well-integrated modes of public transport with well thought out strategies of urban planning, and the trade-offs between transport, land use, and environmental aspects. [ABSTRACT FROM AUTHOR]

This paper presents two redundancy indices for road traffic network junctions and also an aggregated network redundancy index. The proposed redundancy indices could be implemented to identify optimal design alternatives during the planning stage of the network junctions whereas the aggregated network redundancy index could assess the best control and management policies under disruptive events. Furthermore, effective measures of network redundancy are important to policy makers in understanding the current resilience and future planning to mitigate the impacts of greenhouse gases. The proposed junction indices cover the static aspect of redundancy, i.e. alternative paths, and the dynamic feature of redundancy reflected by the availability of spare capacity under different network loading and service level. The proposed redundancy indices are based on the entropy concept, due to its ability to measure the system configuration in addition to being able to model the inherent uncertainty in road transport network conditions. Various system parameters based on different combinations of link flow, relative link spare capacity and Relative Link Speed (RLS) were examined. However, the two redundancy indices developed from the combined RLS and relative link spare capacity showed strong correlation with junction delay and volume capacity ratio of a synthetic road transport network of Delft city. Furthermore, the developed redundancy indices responded well to demand variation under the same network conditions and supply variations. Another case study on Junction 3A in M42 motorway near Birmingham demonstrated that the developed redundancy index is able to reflect the impact of the Active Traffic Management (ATM) scheme introduced in 2006. [ABSTRACT FROM PUBLISHER]

The article offers information on several aspects of traffic engineering including traffic congestion, the Smart Move advertisement campaign and need of competitive funding.

Driving behavior from vehicle interactions, such as acceleration, deceleration, and stop-and-go, is highly associated with traffic environment and safety conditions. This study is intended to investigate the connection between traffic environment and safety, more specifically, vehicle emissions and crash potential occurring in freeway traffic. Individual vehicle trajectory data collected from the US-101 freeway are used to investigate the relationship. Vehicle emission and crash potential indices are derived to characterize traffic environment and safety conditions, respectively, and relate those indices using correlation and regression. The resultant findings reveal that vehicle emissions are positively correlated with crash potentials in a statistically significant relationship. The methodological process for vehicle emissions and crash potential estimation developed in this study is expected to be used to monitor vehicle emissions from traffic conflict potential. Correspondingly, the methodological process is also to evaluate traffic control technology and policy implementation for improvement of transportation system efficiency with the goal of transportation emissions reduction. [ABSTRACT FROM AUTHOR]

Neural networks' (NNs) capability of mapping the nonlinear functions of variables describing the behaviour of objects and the simplicity of designing their configuration favours their applications in transport. This paper presents representative examples in the scope of prediction of road traffic parameters, road traffic control, measurement of road traffic parameters, driver behaviour and autonomous vehicles, and transport policy and economics. The features of the solutions are examined. The review shows that feedforward multilayer neural networks are the most often utilised configurations in transportation research. No systematic approach is reported on the optimisation of the NN configurations to achieve a set level of performance in solving modelling tasks. [ABSTRACT FROM AUTHOR]

Shifting commuters out of cars and into active modes of transportation such as bicycling is necessary if communities and cities are to become more environmentally sustainable. Coupled with the resistance of drivers to change modes is a resistance on behalf of the politicians they elect to support the building of infrastructure for active transportation, particularly when this means taking resources away from the dominant automobile-based mode. Before scholars promote specific policies or methods for dealing with such issues, it is necessary to understand what strategies have been successful and unsuccessful in attaining a shift of resources into active transportation infrastructure such as bicycle lanes. Vancouver presents a case study of both such strategies. In 1996 a pilot project aimed at transferring a lane on the Burrard Street Bridge from cars to bicycles failed and ended in political acrimony. However, another such pilot attempted in 2009 was successful with the lanes made permanent shortly afterward. This article documents what transpired and analyzes the reasons for the initial failure and the subsequent realization 13 years later. The Burrard Street Bridge story provides lessons for how bicycle lanes, even those that take space away from cars, might be implemented in other contexts, given the reality of a politics that favors a status quo dominated by automobility. [ABSTRACT FROM PUBLISHER]

Selfish routing, represented by the User-Equilibrium (UE) model, is known to be inefficient when compared to the System Optimum (SO) model. However, there is currently little understanding of how the magnitude of this inefficiency, which can be measured by the Price of Anarchy (PoA), varies across different structures of demand and supply. Such understanding would be useful for both transport policy and network design, as it could help to identify circumstances in which policy interventions that are designed to induce more efficient use of a traffic network, are worth their costs of implementation. This paper identifies four mechanisms that govern how the PoA varies with travel demand in traffic networks with separable and strictly increasing cost functions. For each OD movement, these are expansions and contractions in the sets of routes that are of minimum cost under UE and minimum marginal total cost under SO. The effects of these mechanisms on the PoA are established via a combination of theoretical proofs and conjectures supported by numerical evidence. In addition, for the special case of traffic networks with BPR-like cost functions having common power, it is proven that there is a systematic relationship between link flows under UE and SO, and hence between the levels of demand at which expansions and contractions occur. For this case, numerical evidence also suggests that the PoA has power law decay for large demand. [ABSTRACT FROM AUTHOR]

In this paper, we consider repeated routing games with piecewise-constant congestion taxing in which a central planner sets and announces the congestion taxes for fixed windows of time in advance. Specifically, congestion taxes are calculated using marginal congestion pricing based on the flow of the vehicles on each road prior to the beginning of the taxing window (and, hence, there is a time-varying delay in setting the congestion taxes). We motivate the piecewise-constant taxing policy by that users or drivers may dislike fast-changing prices and that they also prefer prior knowledge of the prices. We prove for this model that the multiplicative update rule and the discretized replicator dynamics converge to a socially optimal flow when using vanishing step sizes. Considering that the algorithm cannot adapt itself to a changing environment when using vanishing step sizes, we propose adopting constant step sizes in this case. Then, however, we can only prove the convergence of the dynamics to a neighborhood of the socially optimal flow (with the size of the neighbourhood being of the order of the selected step size). The results are illustrated on a nonlinear version of Pigou’s famous routing game. [ABSTRACT FROM AUTHOR]

Traffic forecasting is crucial for policy making in the transport sector. Recently, Selby and Kockelman (2013) have proposed spatial interpolation techniques as suitable tools to forecast traffic at different locations. In this paper, we argue that an eventual source of uncertainty over those forecasts derives from temporal aggregation. However, we prove that the spatio-temporal correlation function is robust to temporal aggregations schemes when the covariance of traffic in different locations is separable in space and time. We prove empirically this result by conducting an extensive simulation study on the spatial structure of the Milan road network. [ABSTRACT FROM AUTHOR]

Global shipping is a backbone of the global economy, and as such, it evolves alongside the development of trade and the elaboration of commodity chains. This paper investigates the evolution of regional inequality in the global shipping network by analyzing the changing positions of world regions during the period from 2001 to 2012. This was a period of both prosperity and recession in maritime shipping. Using data on inter-regional flow connections, the positions of seventeen regions in the global shipping network are analyzed in terms of their traffic development, centrality, dominance and vulnerability. The East Asian, Northwest European and Europe Mediterranean regions have consistently held the highest positions, while East African and North African regions have held the lowest positions. By commanding the largest flows in the network, East Asia assumes a dominant position. The Australasian, North American West Coast, Northwest European and Southern African regions show an increasing dependency on East Asia. The analysis also identifies a few emerging regions that have had the highest growth rates in total traffic volume and connectivity for the studied period, namely South American North Coast, South American East Coast, West Africa, Southern Africa and West Asia. The empirical results of this paper supplement existing research on global shipping network evolution. One implication of the analysis is that the traffic growth of East Asia does not imply that, there is an equivalent improvement in its position in the global shipping network. The paper also shows that indicators from network analysis may be used to provide a more nuanced understanding of port-regional development than existing measures based solely on total traffic volume. [ABSTRACT FROM AUTHOR]

Delineating travel patterns and city structure has long been a core research topic in transport geography. Different from the physical structure, the city structure beneath the complex travel-flow system shows the inherent connection patterns within the city. On the basis of taxi-trip data from Shanghai, we built spatially embedded networks to model intra-city spatial interactions and to introduce network science methods into the analysis. The community detection method is applied to reveal sub-regional structures, and several network measures are used to examine the properties of sub-regions. Considering the differences between long- and short-distance trips, we reveal a two-level hierarchical polycentric city structure in Shanghai. Further explorations of sub-network structures demonstrate that urban sub-regions have broader internal spatial interactions, while suburban centers are more influential on local traffic. By incorporating the land use of centers from a travel-pattern perspective, we investigate sub-region formation and the interaction patterns of center–local places. This study provides insights into using emerging data sources to reveal travel patterns and city structures, which could potentially aid in developing and applying urban transportation policies. The sub-regional structures revealed in this study are more easily interpreted for transportation-related issues than for other structures, such as administrative divisions. [ABSTRACT FROM AUTHOR]

The report touches on the road safety performance in the past few years, road user behaviour related problems in the country and the indicative priorities for measures, actions and campaigns that are laid in the National strategy for improvement of the road traffic safety in Bulgaria 2011-2020. [ABSTRACT FROM AUTHOR]