Exploring impacts of countdown timers on traffic operations and driver behavior at a signalized intersection in Bangkok

This study aims to explore the impact of the countdown timer at various stages of the signal cycle, using two approaches: a traffic analysis and a public opinion survey conducted in Bangkok. The traffic analysis made a comparison of traffic characteristics during an off-peak day time at a selected intersection when the countdown timer was in operation against when it was switched off. A public opinion survey was conducted on more than 300 local regular drivers who are familiar with the technology. It was found that the presence of the countdown timers at the intersection would help to reduce the start-up lost time at the beginning of the green phase by 22%, and reduce the number of red-light violations during the beginning of the red phase by 50%. Furthermore, more than half of the local drivers reported that the timers help to relieve the frustration caused by stopping for uncertain amounts of time during the red phase. However, the timer was also found to slightly reduce the saturation flow rate during the green phase. The public opinion survey showed that the majority of the local drivers were favorable towards the system, and would support the municipality installing such devices on the street network.     

Adaptive nature of coordinated road traffic injury prevention responses in some OECD countries

This study examines the context of coordinated responses, triggers for coordinated responses, and preference for or choice of coordinating strategies in road traffic injury prevention at a local level in some OECD countries. This aim is achieved through a mixed-methodology. In this respect, 22 semi-structured interviews were conducted with road traffic injury prevention experts from five OECD countries. In addition, 31 professional road traffic injury prevention stakeholders from seven OECD nations completed a self-administered, online survey. It found that there was resource limitation and inter-dependence across actors within the context of road traffic injury prevention at a local level. Furthermore, this study unveiled the realization of resource-dependency as a trigger for coordinated responses at a local level. Moreover, the present examination has revealed two coordinating strategies favored by experts in road traffic injury prevention – i.e. self-organizing community groups, which are deemed to have a platform to deliver programs within communities, and the funding of community groups to forge partnerships. However, the present study did not appear to endorse other strategies such as the formalization of coordinated responses or a legal mandate to coordinate responses.In essence, this study appears to suggest a need to manage coordinated responses from an adaptive perspective with interactions across road traffic injury prevention programs being forged on a mutual understanding of inter-dependency arising out of resource scarcity. In fact, the role of legislation and top-down national models in local level management of coordinated responses is likely to be one of identifying opportunities to interact with self-organized community groups and fund partnership-based road traffic injury prevention events.     

Children’s independent mobility in Portugal: effects of urbanization degree and motorized modes of travel

This study is aimed to evaluate the impact of urbanization in children’s independent mobility in Portugal. Mobility licenses, actual mobility, fear of traffic, stranger danger and sense of community were compared in highly, moderately and non urbanized environments and according to gender. Results showed that increase of urbanization leads to a decrease of children’s licenses to independently cross and cycle main roads; go out after dark and go to places other than school. The rising of urbanization leads to an increase of children’s mean age for independent active travel; and at the same time a decrease of independent active school-home travel and leisure time activities. Parental fear regarding traffic is the most frequent cause for concern regarding children’s safety when they are outdoors. Stranger danger and low sense of community are more prevalent in parents from the highly-urbanized environment. Overall, girls enjoy less actual mobility than boys. The discussion shows that children’s freedom of movement in the highly-urbanized setting is very restricted due to a pervasive automobile dependence, proposing a shift from a motorized to a walkable city.     

Making urban road pricing acceptable and effective: searching for quality and equity in urban mobility

Urban Road Pricing has been proposed many times as a powerful instrument to fight congestion in urban traffic, but has systematically faced a hostile political envirionment, due to lack of confidence on its promised (traffic) results and fear of its political consequences. Lack of action in this front is contributing to stable or even growing congestion problems in most large cities.This paper tries to address the problem with a fresh look at the objectives of road pricing and at the reasons for that political hostility. For managing and developing the urban mobility system, efficiency and equity are normally taken as the basic economic objectives. Sustainability objectives may be integrated in the efficiency objective if we are able to represent adequately the costs of the resources consumed in the process. Political hostility is normally based on having to pay for what was freely available, and on the risk of exclusion for those with little revenue available for the extra cost of driving into the city.Pursuit of efficency leads to suggestion of marginal social cost pricing but this is hard to explain to the public and application of this principle is fraught with pitfalls since some components of that cost get smaller as traffic grows (noise related costs for example). Pricing is still a good option but the objective has to be something easier to understand and to serve as a target for mobility managers. That “new” objective is quality of the mobility system, with a meaning similar to that of “level of service” in traffic engineering, and prices should be managed to across space, time and transport modes in such a way that provision of service is made with good quality in all components.Pursuit of equity leads to some form of rationing, which has often been associated with high transaction costs and abuse by the administrators. But the use of electronic road pricing should allow easy ways to address the rationing process without such high costs. The basic proposition is that all local taxpayers receive as a direct restitution of their tax contribution a certain amount of “mobility rights”, which can be used both for private car driving in the tolled areas and for riding public transport.These principles are easily applicable with a variety of technical solutions for road pricing, from the simplest cordon pricing to the more sophisticated “pay-as-you-go” schemes. The paper addresses this question of implementation and argues for increasingly sophisticated schemes, as people get accustomed to the principles and finer targeting of demand segments may be needed.     

Ex-post environmental and traffic assessment of a speed reduction strategy in Madrid's inner ring-road

Since urban traffic is a major source of CO₂ and NO_x emissions, cities play a key role averting climate change and combating air pollution. Most researchers agree on the need of designing comprehensive mitigation strategies instead of applying isolated measures. Nevertheless, it is important to understand the specific impact and scope of each measure to look for the most effective synergies among them. In 2004, the Madrid City Council launched a plan to re-design its inner ring-road to move traffic out of the city centre. For safety reasons the planned speed limit for the full-renovated South-West section was finally reduced from 90 km/h to 70 km/h. Besides contributing to traffic safety, this strategy could also be seen as positive to the environment due to the associated reduced fuel consumption and lower emissions. However, lower speed limits have lower rates of community acceptance due to its impact on average travel times at the individual level. This paper conducts an ex-post evaluation of this speed reduction strategy to explore its environmental and traffic performance impacts. The results support the thesis that, in this velocity range, lower speed limits present important opportunities for reducing GHG and air pollution in the section affected by the measure, without substantially altering traffic performance. The implementation of the new speed limit policy produces a 14.4% and 16.4% reduction in CO₂ and NO_x emissions respectively, while global travel time remains virtually constant and the saturation rate decreases slightly. Besides, this cost-effective measure reveals great potential to reduce air pollution in highly populated urban areas located next to urban highways. This work provides local policy makers and city managers with useful insights regarding potential co-benefits of traffic optimization and speed reduction management to reduce mobile source emissions in urban environments.     

Aspects of Residents' Perceptions of the GMC 400 - Canberra's V8 Supercar Race

The Inaugural GMC 400 Super Car Race was held in Canberra, Australia, on 11 June 2000 within the Parliamentary Precinct of the national capital. Some debate arose in the media about the appropriateness of the event for Canberra in general, and for the zone in particular. While the event was shown on television to all Australians, it is the residents of Canberra who are most affected by the traffic, by the visual impact of the infrastructure, and by other social costs. The residents are also the ones who experience any social benefits such as the excitement and the pride of hosting the event. This paper presents the results of a telephone survey of local residents conducted immediately after the weekend of the race to gauge residents' perceptions of the event and to test for differences in attitudes amongst different groups. Overall, the results of this study recognised that residents experienced some disruption and perceived some negative impacts of the event; however, they also perceived some of the positive impacts such as promotion for the national capital and community pride. The study also revealed that residents' perceptions differed according to several intrinsic variables, including attendance at the event, employment as a result of the event, interest in motorsports, and residential proximity to the race circuit.     

A research on social impacts of the Foça Rock Festival: the validity of the Festival Social Impact Attitude Scale†

The purpose of this study is to examine the validity of the instrument proposed by Delamere, T. A., Wankel, L. M., & Hinch, T. D. [(2001). Development of a scale to measure resident attitudes toward the social impacts of community festivals, Part I: Item generation and purification of the measure. Event Management, 7, 11–24] and to assess the local residents' perceptions of the Foça Rock Festival, which was held in Foça, Turkey. In order to achieve the validity of the instrument, confirmatory factor analysis with LISREL 8.8 was employed, the composite reliability, the estimated percentage of variance extracted by each construct, the discriminant and convergent validity were examined. Results indicated that the local residents' perceptions have two main dimensions with five sub-factors. Furthermore, the results also suggest that these two dimensions (social benefits and social costs) can be measured by 35 items instead of using all 47 items. The collective results indicate that when convergent and discriminant validities are achieved, construct validity is supported. The results also suggest that social benefits dimension is perceived positively by the local residents. On the other hand, other important findings of this study related to the social costs of the festival are the increases in traffic congestion, pedestrian traffic, ecological damage, litter and overcrowding.     

Commute mode diversity and public health: A multivariate analysis of 148 US cities

Urban sprawl has a negative relationship with regional health outcomes, such as high obesity and chronic diseases related to physical inactivity. At the same time, literature has shown that walkable built environments are connected to lower obesity rates and increased physical activity. Less understood is the association of modal diversity with those health outcomes. This research studies a range of public health outcomes to determine their associations with commute mode diversity. Researchers adapted the methodology of urban sociologists Harvey Molotch and Richard Appelbaum to explore twelve different health measures in 148 US counties and their metropolitan statistical areas. The test measure is the percentage of commuters who use some means other than a single-occupant vehicle (SOV). The percentage of such commuters ranges from as low as 11% in Houston County, Alabama to as high as 36% in Honolulu County, Hawaii. Using bivariate and multivariate analyses, we found better health outcomes in counties and metropolitan areas that have fewer workers commuting by SOV. These findings underscore the positive impact of sustainable transportation policies on community health and open up a new direction for public health research and the built environment.     

The reflection of the fear of falls and risk of falling in walking activity spaces of older adults in various urban environments

Participation of older adults in daily activities has a major positive impact on health and contributes to a sense of accomplishment, satisfaction, self-efficacy, and well-being. Walking is considered to be one of the most influential activities promoting health and active living. Older adults are particularly vulnerable to their immediate local environment where age- related declined capabilities combined with barriers in the home neighborhood pose a risk of falling and fear of falls. Most research focusing on the built environment role in incidents of older adults' outdoor falls and fear of falls is focused on identifying the environmental features' risk factors. Effort is made to develop audit checklist tools to assess out-door falls risk. In contrast, this study focuses on the manifestation of fear of falls in older adults' walking activity spaces. We identify spatial walking patterns of outdoor daily activities in public urban spaces and examine the relations between fear of falls, risk of falling status, previous occurrence of fall incidents and number of medical diagnoses and walking activity spaces among older adults in different urban environments.The analysis included 271 older adults (age 60+ with 70% females and 30% males), and 483 walking routes in three cities. A psychological measure related to mobility self-efficacy was evaluated by the Falls Efficacy Scale examining the fear of falling through a functional perspective. Motor evaluation was conducted by functional mobility evaluation through the Timed Up and Go (TUG) screening test which assesses the level of risk of falling. GIS analysis was conducted for mapping and identifying walking activity spaces. The analysis shows different walking activity spaces of people with high risk of falling and fear of falls in comparison to those with no risk and no fear of falling across gender and age groups (60–65, 66–74, and 75+). In this approach we show the outcome reflection of barriers and enablers and their revealed cumulative effect through walking activity spaces among older adults.     

Is there a case for replacing parking charges by road user charges?

The price of parking is often considered an important tool with which to influence transport choice but, since many local authorities have limited control over off-street charges and since parking charges have no direct impact on through traffic, its influence on overall travel demand may be limited. Road user charges, on the other hand, do appear to offer an effective means of influencing overall demand. The problem is that public acceptance of such charges is low unless some obvious “carrot” can be identified. This paper explores the possibility that the removal of parking charges might be that “carrot”. Our analysis suggests that, although the removal of parking charges would reduce revenues and dilute the reduction in demand caused by the introduction of road charges, the combined effect might, in certain circumstances, be more beneficial to the local economy and might still yield a net increase in revenue. Given the incidence of impacts, it also appears that a combined scheme would be more equitable and might stand a greater chance of achieving public acceptance than a more conventional road charging scheme. The paper identifies the circumstances in which a combined scheme might work well and outlines the detailed analysis that would be necessary to confirm this.     

Determinants of airport cost flexibility in a context of economic recession

The recent economic downturn led to a significant contraction in the global demand for air travel and cargo. In spite of that, airports’ operating costs did not mirror the traffic trends and kept increasing during the same period, showing evident signs of lack of flexibility. With this background, this paper aims at identifying the drivers of airport cost flexibility in a context of economic recession. This is done by estimating a short-run stochastic cost frontier over a balanced pool database of 194 airports worldwide between 2007 and 2009. Using the total change in cost efficiency during the sample period as a proxy for cost flexibility, the impact of variables such as ownership, outsourcing, airline dominance, low-cost traffic, and revenue diversification is tested in a second-stage regression. Contrary to the existing literature, a higher level of outsourcing is shown to reduce cost flexibility. Results also indicate that low-cost traffic, diversification, and corporatization increase the airports’ ability to control costs. The negative impact of airline dominance suggests the need for more stringent regulations on slot allocation at congested airports in order to ensure optimal infrastructure usage.     

Customer issues related to limited air connectivity

Air access can be crucial for regional economic development, especially when global industries are involved. However, air traffic generates negative impacts, such as noise and air pollution that can lead to politically motivated calls to reduce air traffic. This paper investigates customer issues and potential responses of frequent flyers to non-market-driven limitations on air transport. Based on a survey conducted at Zurich International Airport we show that frequent air travelers tend to be more senior and to work in industries that involve travel outside of the worker's country of origin. Consequently, they are more critical of potential restrictions on air travel.     

Investigating the associations between road network structure and non-motorist accidents

Road networks channel traffic flow and can impact the volume and proximity of walking and bicycling. Therefore, the structure of road networks—the pattern by which roads are connected—can affect the safety of non-motorized road users. To understand the impact of roads’ structural features on pedestrian and bicyclist safety, this study analyzes the associations between road network structure and non-motorist-involved crashes using data from 321 census tracts in Alameda County, California. Average geodesic distance, network betweenness centrality, and an overall clustering coefficient were calculated to quantify the structure of road networks. Three statistical models were developed using the geographically weighted regression (GWR) technique for the three structural factors, in addition to other zonal factors including traffic behavior, land use, transportation facility, and demographic features. The results indicate that longer average geodesic distance, higher network betweenness centrality, and a larger overall clustering coefficient were related to fewer non-motorist-involved accidents. Thus, results suggest that: (1) if a network is more highly centered on major roads, there will be fewer non-motorist-involved crashes; (2) a network with a greater average number of intersections on the shortest path connecting each pair of roads tends to experience fewer crashes involving pedestrians and bicyclists; and (3) the more clustered road networks are into several sub-core networks, the lower the non-motorist crash count. The three structural measurements can reflect the configuration of a network so that it can be used in other network analyses. More information about the types of road network structures that are conducive to non-motorist traffic safety can help to guide the design of new networks and the retrofitting of existing networks. The estimation results of GWR models explain the spatial heterogeneity of correlations between explanatory factors and non-motorist crashes, which can support regional agencies in establishing local safety policies.     

An intersectional analysis of barriers to cycling for marginalized communities in a cycling-friendly French City

In French cities like Grenoble, cycling is an increasingly popular form of urban mobility. Yet a lack of disaggregated modal data makes it unclear who does and who does not have access to biking. An intersectional analysis of 19 narrative and semi-structured interviews with policymakers, residents with different identities, and bike service providers demonstrate that some people perceive unique barriers to biking, related to their identities. For example, this study finds that racism, financial precarity, a lack of accessible information about services, and spatial inequalities may prevent some people from biking despite Grenoble's advanced cycling infrastructure and services and that these barriers may compound for certain people, reinforcing the preliminary body of research on intersectional barriers to urban biking. The study further finds that the lack of disaggregated demographic data on urban mobility in France might be preventing inclusive bike policy. The paper concludes by arguing that local policymakers would benefit from applying an intersectional analysis in understanding who is and is not biking, to promote everyday biking in a more inclusive way.     

The unpredicted rise of motorcycles: A cost benefit analysis

This article examines the consequences, for Paris, of the increase in two-wheel motor vehicle (2WMV) traffic (measured in vehicle/km). Our study reveals that, between 2000 and 2007, the subway's (Métro) share in total inner-Paris travel increased by 13.6%, the RER's share by 10.3% and the SNCF's share by 20.5%. These three means of transport account for 58% of daily travel. On the other hand, the bus share has decreased by 16% and that of cars by 23.7%. Private motor vehicles represent 37.3% of total travel. Looking at road traffic, where public transport (buses) and private motor transport compete for the use of limited road space, private motor vehicles account for 91.5% and public transport 8.5% of total travel.The 2WMV share in Paris traffic increased by 36% between 2000 and 2007, with 2WMVs now accounting for a share twice as large as that of buses. A survey has shown that 100 million additional passenger kilometres were made by 2WMV in 2007 compared to 2000. 53% of this increase comes from people shifting to 2WMV from public transport and 26.5% from private cars. The remaining 20% is attributable to the increased use of 2WMVs by those already owning such vehicles in 2000.Is the growth in the share of 2WMV traffic in Paris beneficial to the community? This shift in the means of transport generates time savings of €293 million and increases owners' vehicle usage costs by €49 million. The cost of accidents is increased by €49 million and the negative consequences in terms of pollution are estimated at €22.6 million. The welfare impact of the government revenue change is negative and equal to €4.7 million. In total, the gain for the community is therefore around €168 million. Accident costs are the key issue. The fact that there are on average 21 2WMV fatalities in Paris (average 2006–2007) for a means of transport accounting for 16% of passenger/km made every day in Paris offers a striking contrast to the 6 (average 2006–2007) fatalities concerning cyclists which account for a mere 0.1% of trips. The massive shift to 2WMV has taken place without any public policy support. Public policy could easily further improve the 2WMV cost-benefit balance by taking measures that would decrease the number of accidents.     

High-speed rail and regional development: the case of intermediate stations

High-speed rail has developed both nationally and internationally in Europe as a successful alternative to both air and road over distances of 400–600 km. Inter-city traffic, especially between the major metropolitan areas in North-west Europe has benefitted greatly from the investment in this network. This paper explores two issues: the impact on the intermediate areas between these major metropolitan areas and the creation of potential cross-border inter-regional services. The evidence shows how both levels of service and potential economic impacts have been much less pronounced in these intermediate areas. Such areas have been affected both by a failure to see greatly improved direct access to major cities other than within their own countries and a lack of new cross-border inter-regional services. The paper argues that the creation of the high-speed rail TEN-T has not met the primary objectives of reducing regional disparities in accessibility or reducing the effect of national borders on regional integration. To achieve this requires not just infrastructure provision but an appropriate regulatory framework for service provision and accompanying measures at the local level.     

Informal,essential and embedded: Transport strategies in remote Sarawak

Transport is a main concern for people living in rural and remote communities around the world, where the absence of affordable and reliable transport often prevents access to education, health services and employment opportunities. In Sarawak, a state of Malaysia on the island of Borneo, many rural villages experience acute transport poverty. For their basic transport needs, people here rely on informal transport systems based on local social and cultural networks, which provide essential mobility.We apply Polanyi's concept of social embeddedness to explore mobility in this region, people's efforts to develop regional models of entrepreneurship but also the relative marginalisation of remote communities in terms of development and infrastructure provision and the resulting friction between local people, the companies involved in regional resource extraction activities and local government. Based on data collected between 2015 and 2017, we frame informal transport in this region as a form of Indigenous entrepreneurship that can help local communities achieve wider social and economic inclusion. Our research points to a more social type of entrepreneurship and economic practice, in which social relationships and community responsibilities play an important role. Our qualitative approach, including ethnographic methods such as semi-structured interviews and participant observation, underpins the groundedness of our data in the every-day experiences of the people who took part in the research.     

“I am like a deaf,dumb and blind person”: Mobility and immobility of Chinese (im)migrants in Flushing,Queens, New York City

This paper contributes to research on daily mobility experience of (im)migrants in cities and expands the conceptualizations of mobility by examining intentionality and its relations to locality. Through place-based research on mobility and immobility of Chinese (im)migrants in Flushing, Queens, New York City, this paper explores: 1) mobility patterns of recent (im)migrants in an urban setting; 2) the constraints, resources and their coping strategies for everyday mobility; and 3) the dialectal relationship between voluntary and involuntary immobility, and between mobility and ethnic communities. This study reveals that immobility is not always the result of inaccessibility, but structural barriers in the broader society such as socioeconomic inequality and racial discrimination. Involuntary immobility encourages overdependence on locality. With its high place accessibility, Flushing provides (im)migrants with a plethora of ethnic mobile resources, as well as social networks and community resources. The relative immobility among Chinese (im)migrants in Flushing is compensated by the flows and movements of people, goods and information both at the local and transnational scale. The contrast between insider-ness and outsider-ness further enhances their attachment to the local community and discourages them from moving. Thus, locality mitigates involuntary immobility but paradoxically nurtures voluntary immobility that hinders the transfer of potential mobility to actual mobility, and physical mobility to social mobility. Without considering locality, stillness is easily mistaken for immobility; without considering intentionality, accessibility is easily equated to mobility. Therefore, solutions to transportation equity do not lie solely in transportation accessibility itself, but more broadly in individual capability, immigration policy, labor market equality and community development.     

The factors in residents' mobility in rural towns of China: Car ownership,road infrastructure and public transport services

The improvement of rural people's mobility in developing countries has informed many policies. Still, debates remain on which policies are efficient, for instance, building more roads, providing public transport or promoting car ownership. The empirical evidence for these debates at the national level remains scarce. As a result, this paper aims to provide fresh evidence for discussions by examining residents' mobility in China using nationwide survey data with 12,524 respondents from 119 rural towns. The results of the analysis show car ownership is the most significant factor influencing rural people's mobility than other factors. Higher car ownership relates to a higher travel frequency to counties or cities. Other kinds of transport vehicles (i.e. electric cars, motorcycles and electric bikes) also have positive but relatively weaker impacts on rural mobility. For public transport, it is more accessible to access bus stops, which encourages travel to higher-order centres rather than increasing the frequency of county bus services. The accessibility of high-quality road systems tends to have a negative influence and has combined effects with levels of local services. People from towns with insufficient local services and poor access to highways travel the most frequently to higher-order centres. This study highlights the critical role of road investments and car ownership enhancement policies in improving mobility. Moreover, this study also underscores the supplemental role of public transport services given the current low car ownership rates in rural towns of China and the global consensus on sustainable green transport development. It highlights the importance of engaging eco-friendly and locally adaptive transport alternatives, such as electric cars and electric bikes. It also calls for a rational distribution of bus stops and more flexible, convenient, and physically accessible public transport and carshare modes in rural China.