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A sound understanding of transport energy efficiency is of paramount importance. It has been widely accepted that a higher level of urban density is associated with a more significant amount of energy consumption in long-distance travel, including international trips. Meanwhile, its negative correlation with domestic long-distance travel was reported in only a few studies. In addition, the analysis of domestic long-distance travel and its transport energy efficiency has yet to be thoroughly conducted. Therefore, this study first assesses the transport energy efficiency of various transportation modes (roadways, railways, aviation, and waterways) in the form of energy intensity, and then obtains the overall transport energy intensity (OTEI) in the domestic long-distance travel in Japan by considering the social modal choice. Finally, its association with distance, income per capita, and population density in Japan is evaluated, and the results are compared with the case in the United Kingdom, France, and the United States. It was found that higher income per capita is associated with lower energy intensity for domestic long-distance travel in Japan. The relationship in Japan between OETI for domestic long-distance travel and traveled distance is observed as a U-shaped form.

Until recently, addressing the environmental externalities associated with the use of the private car and single occupancy vehicles has been the focus of the airport ground access policies worldwide. However, with the emerging unprecedented challenges of the COVID-19 pandemic, which have already changed the way we live, work, and travel, encouraging a change in commuter behavior has become even more important. This has necessitated that existing strategies be reconsidered in favor of adapting to a highly uncertain “COVID-19 world.” Historically, there has been a dearth of literature relating to airport employees’ ground access even though as a group employees represent an important segment of airport users with complex access requirements. This paper therefore focuses on airport employee related airport ground access strategies considering an emerging understanding of the future impacts of COVID-19 on global air travel. Pre-COVID strategies are investigated by conducting a documentary analysis of the most recent ground access strategies of 27 UK airports. The findings reveal that airport ground access strategies were mainly focused on setting targets and producing policy measures in favor of reducing car use and increasing the use of more sustainable transport modes including public transport, car sharing, and active travel (walking, cycling). However, measures encouraging public transport and car sharing will be more difficult to implement because of social distancing and fear of proximity to others. Instead, initiatives encouraging remote working, active travel, and improved staff awareness will be at the forefront of the future ground access strategy development.

Rising traffic congestion and severe air pollution in urban areas have led policymakers to find appropriate strategies to encourage the use of sustainable modes. In this context, this paper investigates three choice dimensions related to the work commute travel: (i) Whether and to what extent are sustainable modes considered? (ii) What factors influence the propensity to shift from the primary work commute mode? (iii) Which mode is most likely to be chosen conditional on the decision to shift? These dimensions are analyzed using data of workers from Chennai, India. As the three choices of an individual may be correlated and mutually endogenous because of common and persistent psychological attributes and modal service characteristics, they are modeled using a multi-dimensional probit model. The results show significant evidence of endogeneity, state-dependence, and unobserved correlation across these dimensions leading to significant improvement in fit measures. The results show that perceptions of walkability and environmental impacts of travel modes affect only the consideration of sustainable modes, while vehicle ownership and accessibility to transit affect all three dimensions. Four different behavioral motivations for the decision to shift from the usual mode: dissatisfaction with service attributes, activity constraints, multimodal travel pattern, and inertia, were identified. The mode to which shift occurs is influenced by household vehicle fleet (number and type), exclusive availability to the given decision-maker, and work distance. The insights from this study can be used to identify suitable factors and frame policies to promote sustainable mode choice at various levels.

A marriage between dockless bike-sharing systems and rail transit presents new opportunities for sustainable transportation in Chinese cities. However, how to promote the bicycle–metro integration mode remains largely unstudied. This paper designs a public–private partnership program to promote bicycle–metro integration. We consider the cooperation between bike-sharing companies and rail transit companies to improve both services and attract long-distance travelers to choose the bicycle–metro integration mode, with government subsidies. To analyze the proportion of each population participating in this public–private partnership program, we establish an evolutionary game model considering bike-sharing companies, rail transit companies, and long-distance travelers, and obtain eight scenarios of equilibriums and corresponding stable conditions. To prove the evolutionary game analysis, we construct a system dynamics simulation model and confirm that the public–private partnership project can be achieved in reality. We discuss key parameters that affect the final stable state through sensitivity analysis. The results demonstrate that by reasonably adjusting the values of parameters, each equilibrium can be changed into an optimal evolutionary stable strategy. This study can provide useful policy implications and operational recommendations for government agencies, bike-sharing companies, and transit authorities to promote bicycle–metro integration.

Although metro systems are established in many Asian cities including Chengdu, they have yet to cover every corner of a city. Understanding the transfer behavior of passengers can provide insight into achieving efficient and sustainable urban transport systems. Combining shared mobility programs with metro to improve the weaknesses of traditional feeder modes is viewed as the most promising line of business in sustainable transportation for the near future. Therefore, this study aims to comprehend the factors affecting the usage regularity of shared mobility by deepening the knowledge on endogenous and exogenous effects, and integrating two modes, namely bike-sharing and ridesourcing. Two systems are cross-compared, first in respect of their travel characteristics. Then, a binary logistic model is employed to capture the influences of trip characteristics and travel environment characteristics on their usage frequency. Researchers found that trip distance is significantly associated with users’ mode options, indicating that bike-sharing and ridesourcing mainly serve short-distance and long-distance transfer users, respectively, although some users may be confused which feeder mode to choose for the journeys of 2 km to 4 km. There were also meteorological and temporal influences, with the competition and complementation of multiple shared mobility feeder modes being likely to change under extreme weather conditions, during peak hours, or on weekends. Besides, metro-shared mobility users value the accessibility of two kinds of transport service, which is affected by the metro station and its surrounding built environment. This study and the proposed policy implications are helpful for embracing a sustainable mobility design from general optimum.

Mobility, safety, and environmental sustainability are priorities in the geometric design of roundabouts. This paper presents a multi-objective optimization model that determines the geometric design elements of single-lane roundabouts using all three objectives. The user can specify weights for the objectives, or the model can determine the optimal weights. Mobility is defined in terms of roundabout delay and modeled using the United Kingdom empirical model. Safety is modeled in terms of collision frequency based on the methodology of the Highway Safety Manual. Environmental sustainability is represented by vehicle emissions (nitrogen oxides, hydrocarbons, carbon dioxide, and carbon monoxide) and is modeled using the vehicle-specific power methodology. The proposed model directly identifies the optimal geometric dimensions (decision variables) of the roundabout, including entry width, exit width, approach half-width, circulatory width, effective flare length, entry radius, entry angle, and inscribed circle diameter. The input data to the model include traffic data, site conditions, and limitations based on design guidelines. Application of the proposed model is illustrated using two actual roundabouts. The comparison results show that the proposed model provides substantial improvements in safety, mobility, and environmental sustainability compared with existing conditions. In addition, the model requires much less effort to apply compared with the traditional iterative method, and as such should be of interest to highway designers.

The increasing emissions from the transportation sector pose substantial hazards to the environment and human health around the world. With the rapid development of information and communication technologies, ridesplitting, a form of ridesourcing service accessed via smartphone applications, enables passengers with similar origins and destinations to be matched to the same driver and share the ride. This is regarded as a promising travel mode that could mitigate air pollution. However, because of a lack of quantitative analysis, the environmental benefits of ridesplitting have not been rigorously justified. As vast amounts of observed data of ridesourcing have become increasingly available, this study quantifies the environmental benefits of ridesplitting based on the global positioning system (GPS) trajectory and trip order datasets of DiDi Chuxing in Chengdu, China. First, the saved distances of ridesplitting are calculated by analyzing the travel distances of both ridesplitting trips and the corresponding trips under non-ridesplitting conditions. Then, the emission factors of CO, NOx, and HC are estimated by a localized MOVES model. Combining the saved distances and emission factors, the emission reductions from each ridesplitting trip can be calculated. The results show that ridesplitting can decrease the travel distance by 22% on average compared with non-ridesplitting. As a consequence, the average emission reductions per ridesplitting trip are 10.601 g of CO, 0.691 g of NOx, and 1.424 g of HC, respectively. This study provides a better understanding of the environmental benefits of ridesplitting and theoretical guidance for the government’s decision-making in green transport planning.

A deeper understanding of how weather variables affect pedestrian volumes is important, as active travelers are an essential part of a sustainable transportation system. Pedestrian data are limited for investigating the impacts of weather on walking levels, with most studies having data at only a couple of locations. Pedestrian actuation data (from push-buttons at traffic signals) overcomes this limitation. The Utah Department of Transportation archives pedestrian push-button press data for use in its Automated Traffic Signal Performance Measures system. In this study, pedestrian actuation data was used as a proxy for walking activity and weather data was collected from the National Oceanic and Atmosphere Administration. Using 15 months of daily time series data in Cache County, the impacts of weather on pedestrian signal activity were examined at 49 signalized intersections, using a log-linear time series regression analysis with categorical step-wise weather variables. The findings revealed that snow depth had the most frequent negative effect on walking activity. Snowfall (> 0.6 in.) also tended to have negative impacts when significant. Very hot maximum temperatures (≥ 90°F) were associated with lower pedestrian activity at around one-third of signals. Very low minimum temperatures (

Rapid urbanization, increasing population, and a booming economy have stimulated growth in Indian cites, resulting in higher levels of dependence on private vehicles. This has raised serious issues over the sustainability of transport infrastructure in cities. Public transportation (PT) systems can help achieve sustainable transportation. But they face competition from intermediate public transport (IPT) or Paratransit. The existing PT and IPT systems, therefore, need to re-plan their operations to complement each other and deliver a wider network of services. To achieve this, an evaluation of both PT and IPT systems at microscopic levels is needed to facilitate their possible integration in a coordinated multimodal transportation system. The present paper attempts to evaluate the public and paratransit systems in the city of Surat in the Indian state of Gujarat using a data envelopment analysis (DEA) technique in DEAP software at the individual and system level. The operations, route design, and cost efficiency of both systems are evaluated to understand how well the existing set-up caters to demand. The arithmetic mean of operations, route design, and cost efficiencies of 26 routes of PT system were worked out to be 0.89, 0.94, and 0.69, while that of the 13 routes of the IPT system were 0.92, 0.97, and 0.88 respectively. The system investigation shows that analytically, only 8% of IPT routes were inefficient in all the three aspects, compared with 42% of PT routes. The performance of each route was analyzed, appropriate suggestions made, and the potential of these systems for designing an integrated transport system highlighted.

As the world shapes a global agenda to mitigate climate change, national governments are looking to define sustainable development strategies for the transportation sector. In this international landscape, countries will look to learn from one another, but identifying peer countries for this learning can prove a challenge. In this study, we measure public support for transportation policies and use this as a measure of cultural distance to identify peer countries. We modeled public support for 11 transportation policies in an international sample of 41,932 individuals in 51 countries or regions. Using a model that controls for individual effects, we measure pure country-level differences in public policy support. Measuring public support for different transportation policies can help policymakers understand how the public evaluates and envisions the role of government in shaping the current as well as future transportation system, and to anticipate difficulties of implementing certain types of policy because of public resistance. In general, we find the highest public support for a given policy appears in countries that have not yet seen significant investment in the target infrastructure or service. We show that considering public support for transportation policies gives a different perspective than traditional indicators of economic development or level of motorization, helping policymakers understand what the public wants and how they might build support for new transportation policies. Finally, we present a clustering framework that goes beyond development status and geographical adjacency to help identify peer countries for policy learning using public policy support as a measure of cultural distance.

Shared fleets of fully automated vehicles (SAVs) coupled with real-time ride-sharing to and from transit stations are of interest to cities and nations in delivering more sustainable transportation systems. By providing first-mile last-mile (FMLM) connections to key transit stations, SAVs can replace walk-to-transit, drive-to-transit, and drive-only trips. Using the SUMO (Simulation of Urban MObility) toolkit, this paper examines mode splits, wait times, and other system features by micro-simulating two fleets of SAVs providing an FMLM ride-sharing service to 10% of central Austin’s trip-makers near five light-rail transit stations. These trips either start or end within two geofenced areas (called automated mobility districts [AMDs]), and travel time and wait time feedbacks affect mode choices. With rail service headways of 15 min, and 15 SAVs serving FMLM connections to and from each AMD, simulations predict that 3.7% of the person-trip-making will shift from driving alone to transit use in a 3 mi × 6 mi central Austin area. During a 3-h morning peak, 30 SAVs serve about 10 person-trips each (to or from the stations), with 3.4 min average wait time for SAVs, and an average vehicle occupancy of 0.74 persons (per SAV mile-traveled), as a result of empty SAV driving between riders. Sensitivity analysis of transit headways (from 5 to 20 min) and fleet sizes (from 5 to 20 vehicles in each AMD) shows an increase in FMLM mode share with more frequent transit service and larger fleet size, but total travel time served as the biggest determinant in trip-makers’ mode share.

Pedestrian safety is a top priority within the transportation planning community as cities promote sustainable transportation, alternative travel modes, and healthy lifestyles. If people feel unsafe while walking, they will choose other modes of transportation if they are able. To prioritize safety, it is important to know where pedestrian crashes are occurring and with what severity. Using spatial statistical methods including nearest neighbor index, Moran’s I, local indicators of spatial autocorrelation (LISA), and Getis-Ord G-statistic, this study seeks to analyze the pedestrian fatality locations within the state of Ohio over a 10-year period (2007–2016) to identify hot spots, cold spots, and spatial patterns across three different spatial scales: county, census tract, and traffic analysis zone (TAZ). It seeks to understand the effects of aggregated data across these spatial scales on the outcome of the analysis and determine the most useful spatial scale at which to study pedestrian fatalities. The study concludes that spatial analyses at small scales are most informative. It goes on to recommend locations within Ohio for further analysis based on the resulting maps, including areas with outliers. As of writing this, there is no current statewide pedestrian fatality analysis for the state of Ohio.

Liquefied natural gas is emerging as viable and potentially sustainable transportation fuel with intrinsic economic and environmental benefits. Liquefied natural gas possesses thermomechanical exergy amounting to ∼1 MJ kg-1 which is currently wasted on liquefied natural gas vehicles, while it could be used to produce useful work. The present investigation proposes an indirect means of obtaining useful work from liquefied natural gas through charge cooling and also demonstrates additional benefits in terms of NOx emissions and power density. A thermodynamic engine model was used to quantify the performance benefits of such a strategy for a homogeneous-charge, spark-ignited, stoichiometric natural gas engine. Four fuelling strategies were compared in terms of fuel consumption, mean effective pressure and NOx emissions. Compared to the conventional port-injected natural gas engine (where gaseous fuel is injected), it was found that directly injecting the liquid phase fuel into the cylinder near the start of the compression stroke resulted in approximately -8.9% brake specific fuel consumption, +18.5% brake mean effective pressure and -51% brake specific NOx depending on the operating point. Port-injection of the fuel in the liquid phase carried similar benefits, while direct injection of the fuel in the gaseous phase resulted in minor efficiency penalties (∼+1.3% brake specific fuel consumption). This work highlights the future potential of liquefied natural gas vehicles to achieve high specific power, high efficiency and ultra-low emissions (such as NOx) by tailoring the fuel system to fully exploit the cryogenic properties of the fuel.

The urban Sustainable Development Goal (SDG) includes the target to provide “access to safe, affordable, accessible and sustainable transport systems for all” by 2030. However, debate exists around the best indicator to measure this target, and few actual measurements exist. This is in part because basic transit data are missing from many of the world’s cities, including in Africa where popular or “informal” systems dominate. This paper explores how to make progress in measuring indicators for the SDG transport target using Nairobi’s minibus system, matatus, as a case study. We partially measure the SDG indicator for the city as currently defined by the UN and then compare the SDG measurement to a location-based accessibility indicator that incorporates income data, travel times, and land-use considerations for Nairobi’s highly monocentric spatial urban form. We show that although the SDG analysis suggests generally favorable transit coverage, it also points to underlying transport inequalities for low-income residents. The more fine-grained location-based accessibility analysis reveals rapidly decreasing accessibility to opportunities as distance increases from the city’s central business district. This accessibility-based analysis further highlights income-based transport inequalities, identifying opportunities for improving integrated transport for residents living on the city’s near and far peripheries. Improving non-motorized transport access for those living in low-income areas with high access potential would also be important to improve access. We recommend that cities start using open-source software and open data to measure a variety of indicators needed for data-driven policy, to meet SDG 11.2 and go further to improve access to opportunities for all residents.

The main goal of this research is to evaluate the relationship between the built environment and public health of citizens in four different buffers of Sanandaj, Kurdistan province, Iran. There is a growing body of evidence that links the neighborhood design to public health and argues that the built environment impacts on the public health of people through the weakening or strengthening of sustainable transportation (walking, cycling, and public transportation) and physical activity. Regular physical activity has a significant impact on the health of individuals, and this can be the best way to cope with several diseases. The statistical population of this study includes people between the age of 18 and 65 years in Sanandaj city. The method used to investigate the normality of dependent variables is the Kolmogorov–Smirnov test; the assessment of the resident’s difference of physical activities is conducted through one-way variance; the impact of the built environment on physical activities is assessed through a multivariate regression test, and the effect of physical activity on the health of the individuals is evaluated through a correlation test. This study, by explaining the characteristics of the built environment in four different buffers, has exhibited that the environment supporting physical activity of pedestrians plays a critical role in increasing the amount of physical activity they engage in.

Street network analysis is a growing area in sustainable transportation research. Most academic papers on the topic have, so far, been concentrated in Europe and America, with less attention paid to rapidly growing cities in low income nations. This is problematic because transportation networks are rapidly evolving in developing countries and the impacts of misguided transportation policies (including air pollution and road traffic casualties) are particularly acute. Metrics on the performance of street networks could help inform policy. This paper uses the Python package OSMnx to analyze and evaluate street networks in 12 districts of Phnom Penh from OpenStreetMap. Results suggest that topological and geometric characteristics of street networks are more conducive to walking and biking in the central districts than in the peripheral districts. The central districts are also better connected to core network corridors. To promote sustainable urban mobility, new developments and street renewals should be incorporated facilities, services, and safety of walking and biking. Some policy implications are suggested for future designs of the Phnom Penh’s street networks to increase livability and sustainability.

For-hire vehicle trips in the five boroughs of New York City from 2014 to 2017 increased by 82 million annually (46%). This paper describes how factor analysis and cluster analysis were used to create a typology that was applied to quantify how usage patterns have evolved in different types of neighborhood. Having surged 40-fold, ridesourcing trips originating in the outer boroughs now constitute 56% of the overall market. Many of the outer borough neighborhoods in which ridesourcing trips originated are home to minority, relatively low-income populations with low car ownership rates. It is possible that these trips in the outer boroughs are being taken by local residents to fill gaps in mobility services, as these locations are less well-served by public transportation and other for-hire vehicles such as yellow taxis. The surge in ridesourcing trips in the outer boroughs is important for three reasons. First, if ridesourcing is being used to provide desired levels of accessibility by outer borough residents, having this need filled by for-profit entities with notoriously variable pricing structures could have long-term consequences for transportation equity. Second, if the trips represent induced travel, the associated externalities will negatively affect vehicle emissions, greenhouse gas emissions, and transportation safety. Third, local policy makers need to be aware of the dynamics unfolding in the outer boroughs because regulations that have been adopted to reduce congestion currently only apply to trips originating in Manhattan. Moreover, all stakeholders should reassess how disruptive transportation technology companies are regulated with respect to data sharing.

The City of Pasadena adopted new metrics for measuring transportation impact in 2015 that promote sustainable transportation and urban form. This paper describes the process by which conventional impact measures were replaced with metrics for sustainability and describes experiences with implementation of the metrics, development of companion elements, and monitoring performance. The integrated approach to planning, development review, and system management in use in Pasadena provides both a model framework for other cities and highlights the issues that can be encountered when using metrics that are less familiar to the public and decision makers.

Transportation planning has become increasingly interested in the institutional changes needed to implement sustainable transportation measures. This research looks at six U.S. metropolitan areas that are implementing or have recently implemented transit priority projects—Seattle, Portland, Denver, Chicago, New York, and Boston—using interviews with local planners, media accounts, and analyses of project documents. It explores what policy statements and arguments were used to support transit priority, the leadership needed to support implementation, innovative funding arrangements, and the institutional changes within agencies that led to a virtuous cycle of transit improvement. The research found that cities that talked about their transit priority as a way to accommodate growth without cars or to manage street space efficiently were more effective than those who put forth transit priority, and particularly bus rapid transit, as a cheap solution to improve transit. It also found that leadership within city transportation agencies was more important than elected official champions, and that transit agencies can use the promise of increased frequency to leverage city funding for street improvements. Lastly, it found that city streets agencies that are serious about prioritizing transit develop transit planning programs, staffing capabilities, and set regular meetings with transit agencies that they view as partners in improving transit.

The recent and dramatic growth in ride-hailing activity is a bellwether of a coming transportation revolution driven by on-demand services. The impacts of ride-hailing services on the transportation system have been immediate and major. Yet, public agencies are only beginning to understand their magnitude because the private ride-hailing industry has provided limited amounts of meaningful data. Consequently, public agencies responsible for managing congestion and providing transit services are unable to clearly determine who uses ride-hailing services and how their adoption influences established travel modes, or forecast the potential growth of this emergent mode in the future. To address these pressing questions, an intercept survey of ride-hailing passengers was conducted in the Greater Boston region in fall 2017. Ten ride-hailing drivers, recruited and trained by the authors, asked passengers to complete surveys during their ride-hailing trip. The tablet-based survey instrument recorded nearly 1,000 passenger responses with regard to socioeconomic background, mobility options, and trip context. These responses, which enabled a robust description of ride-hailing passengers for the region, were used to analyze how new on-demand mobility services such as Uber and Lyft may be substituting travel by other modes. The study substantiates previous findings and advances knowledge of who is utilizing this new mobility option and what factors influence its adoption over public and active transportation modes. The results are intended to inform public policies ensuring that shared mobility technologies will complement existing multimodal landscapes and not worsen existing environmental concerns or equity gaps related to individual mobility.

Daily home–work travel is a habitual behavior that can be disrupted when the location of work, as one of the behavioral contexts, changes. It is then likely that individuals will reconsider their travel behavior more intentionally and choose alternative transport modes. To identify motivations and barriers to incorporating the use of sustainable modes into the individual’s daily travel, this article systematically reviews the literature on the impacts of involuntary workplace relocation on commuting behavior. Effective measures that incentivize sustainable commuting behavior are also discussed. This study on involuntary workplace relocation informs considerations of changes in travel behavior related to other contextual changes.

The overall goal of this study is to assess the concept of sustainability in relation to the related concepts of “health” and “livability” that have emerged in transportation planning discourse. This study achieves the goal using an indicator-based case study, conducted for the El Paso metropolitan area in the United States. Data from the regional travel demand model and other sources were used to quantify a sustainability index, livability index, and health index for individual traffic analysis zones in the region, for four analysis years over a 30-year planning horizon. Each index was comprised of representative indicators, which were normalized and aggregated in accordance with common multi-criteria decision-making methods. The analysis results demonstrated little correlation between the quantified livability, sustainability, and health indices developed for the El Paso region. The indices also showed relatively low levels of change over time for a location. That is, the relative performance of a traffic analysis zone tended to stay the same, despite the modeled changes to the transportation system, demographics, and land use. The main implication of the research findings is that despite overlaps at a theoretical level, concepts such as livability and health cannot necessarily serve as proxies for sustainability when implemented in practice. The study also provides insight into the challenges of making meaningful change in the area of sustainability over time and highlights the influence of factors beyond transportation, such as land use and socio-economic issues.

University campuses have unique characteristics that influence travel demand. They benefit from controlled planning frameworks, can influence almost all aspects of pricing and on-campus transportat...

Pedestrian infrastructure that is comfortable, connected to destinations of interest, and accessible to those with disabilities is vital to a safe, accessible, equitable, and sustainable transportation system. Planners recognize the benefits of providing well-maintained sidewalks and curb ramps, but often lack the asset management systems necessary to inventory sidewalk maintenance problems, prioritize sidewalk maintenance needs, and track the implementation of sidewalk improvement projects. Communities that are managing sidewalk presence and condition data typically link the data to their roadway network, which makes tracking specific sidewalk assets difficult. This paper introduces an affordable, semi-automated, and easy-to-implement process to generate a GIS-based sidewalk network with associated links and nodes representing crosswalks and intersections. Quantitative sidewalk condition data can be loaded onto the network, which allows it to be used to manage sidewalks as transportation assets, assessing pedestrian accessibility, prioritizing repairs or improvements, and to automatically identify accessible routes between origins and destinations. System inputs include parcel-level land-use and roadway centerline data, both of which are publicly available and free in most cases. The network is generated within the ArcGIS environment, using Python scripts to implement embedded ArcGIS functions. The method requires few computational resources, and tremendously reduces the manual labor required to develop a fully interconnected sidewalk network. Examples from multiple communities are presented to show how quantitative sidewalk condition data are loaded onto the network, and illustrate the network’s potential for pedestrian navigation and routing applications.

This paper analyzes the decoupling states between CO2 emissions and transport development in China from 1994 to 2012. The results indicate that, at the aggregate level, the Chinese transport sector is far from reaching the decoupling state. Negative decoupling or non-decoupling years account for 72.2% of the study period. At the disaggregated level, the decoupling states between CO2 emissions and eight primary fuels are as follows: raw coal and coke are in the absolute decoupling state; crude oil, gasoline and diesel are in the weak negative state; and the other three types (kerosene, heavy fuel oil, and natural gas) are in the strong negative decoupling state. Policy implications underneath the identified decoupling states are also revealed to help China build a more sustainable transportation system.

Securing the objectives for future high-efficiency low-carbon-dioxide vehicles is a key target for automotive manufacturers. This paper considers a high-durability two-stroke cycle engine in terms of performance and computational modelling of the emissions characteristics for automotive range-extender or hybrid electric vehicle power plant application. The engine uses novel segregated pump charging via the application of stepped pistons, and a comparison of the engine characteristics is made with those of a comparable four-stroke cycle engine of similar expected power output (more than 60 kW/l). In the interests of cost minimisation, both engines are limited to parallel two-cylinder in-line configurations with the intention of still being able to achieve acceptably low noise, vibration and harshness characteristics. In order to achieve low engine exhaust emissions, computational modelling of direct injection is considered for the stepped-piston engine. A significant reduction in the nitrogen oxide emissions of between 31% and 55% is observed.

This article reviews the literature on current “best practice” principles for planning public transport (PT) networks within the context of planners seeking to transition their cities toward sustainable mobility. An overview is provided of the history of ideas about network development. The emerging frontiers for multimodal, demand-responsive PT and the potential implications of new transport technology on traditional PT are discussed. The future role of transit-oriented development within PT network structures is considered. The “moderators” to network design that may impede future best practice brings the article to conclusion.

The past decade has seen increased public interest in sustainable transportation modes in the United States. However, there is a relative lack of guidance regarding standards and specifications for bicycle facilities compared with the highway mode. This project sought to address this deficiency through the investigation of alternative pavement markings for bicycle wayfinding and proper bicycle placement at signalized intersections as part of the federal Nonmotorized Transportation Pilot Program in Columbia, Missouri. This evaluation was accomplished with a bicycle simulator study and postsimulator survey with 27 participants. A network of 37 intersections with characteristics similar to intersections in Columbia was created with the ZouSim simulator. The survey included questions regarding bicycling habits and preferences for the alternative markings. For wayfinding, two alternative types of pavement markings and the signage recommended by the Manual on Uniform Traffic Control Devices (MUTCD) were evaluated. Both the survey and the simulator results indicated that the Type 2 wayfinding markings with a green circle performed better with respect to visibility and delineating the bicycle route. The bicycle placement portion of the study investigated three alternative types of markings as well as the MUTCD markings and signage to help riders position their bicycle at the correct location to receive a green signal. The bicycle placement results indicated that the Type 1 and Type 2 experimental detector markings resulted in the fewest number of missed detections, while the Type 1 marking was the preferred alternative of the survey participants.

Promoting walking trips is considered a key element of achieving more sustainable transportation. This paper presents a new index for measuring walkability in metropolitan areas. This index measures walkability levels for diversity and intensity of uses in spatial areas while considering the travel distance and time as travel impedance between origins and destinations. A walking access index (WAI), which is a location-based measure for accessibility, is formulated for quantifying accessibility within local areas in metropolitan Melbourne, Australia. Geographic information system software was employed to compute distances between origins and destinations. The Victorian Integrated Survey of Travel and Activity (VISTA) was used to evaluate the new index and examine the association between walking trips and levels of accessibility within the metropolitan region of Melbourne. Furthermore, the new index is compared with one of the most common approaches using the VISTA data set. Key findings indicate that the WAI has a stronger association with recorded walking trips, with more walking trips recorded in areas with higher values of the WAI.

Off-peak-hour delivery programs are a promising but challenging concept for promoting sustainable urban logistics. Stockholm, Sweden, initialized a nighttime freight deliveries program in 2014, aimed at a more efficient and environmentally friendly delivery system within the central area of the city. The policy of shifting freight deliveries from daytime to off-peak hours generates a wide range of effects that can be analyzed from several angles. This paper identifies the social costs and benefits, how these are distributed between stakeholders, and their effects on the everyday life and operations of all interested parties. Accord-ing to information and data collected through in-depth interviews with private and public stakeholders, the social benefits mainly consist of increased efficiency and productivity for carriers and receivers, reduced transport costs, fuel cost savings, and reduced congestion and accidents when trucks are moved from peak to off-peak hours. Social costs may include increased noise levels and noise disturbances; additional staff requirements, equipment, and wage costs; and higher risks in handling goods deliveries at nighttime, especially in the case of unassisted deliv-eries. This paper concludes by discussing the lessons learned from the trial, challenges and opportunities that arose during implementation, and the implications for enhancement of off-peak-hour delivery in Stockholm and other cities. QC 20171102

To understand and facilitate modal shift to more sustainable modes of transport, there is a need to model accessibility and connectivity at an urban scale using data collection and modelling procedures that require less data and specialist input than traditional transport models. The research described in this paper uses spatial analysis modelling procedures based on space syntax to investigate the potential to model aggregate traffic flows at an urban scale. The research has demonstrated that space syntax modelling is an effective means of representing an urban scale motor traffic network; however, modifications to the original model were required to achieve a correlation between modelled and measured motor traffic flow comparable to other modelling procedures. Weighting methods were tested with ‘boundary weighting’ found to be effective at representing traffic crossing the boundary of an isolated urban sub-area, but not so effective at an urban scale. ‘Road weighting’ was found to be effective in improving model performance by representing traffic flows along routes according to a national classification scheme. The modelling approach has the potential to be extremely useful at an early planning stage to represent changes to flows across the network and to be useful for different modes.

Most current transportation systems around the world are cause for pressing concern and a menace to sustainability of social justice, and economic and environmental vitality. From a universal agreement that transportation needs an urgent alteration in travel modes, policies, planning, and behaviors through to the emergence of sustainability in the transportation sector, a significant and central vision has emerged to guide urban policymakers, transportation planners, and public health officials. During the last four decades, a shift in transportation modes toward use of active modes of transportation has been encouraged, and it is one of the main sustainability movements appearing in many developing and developed countries. This research provides a narrative review and parsing of existing literature, which focuses on promoting active modes of transportation. The aim is to clarify key determinative variables that must be considered by planners and policymakers toward promoting use of active modes of transportation for daily mobility.

The concept of mobility as a service (MaaS) has been proposed as a feasible way to achieve more sustainable transport. One example of such a service is UbiGo, a broker service for everyday urban travel developed and evaluated within the Go:Smart project in Gothenburg, Sweden. This paper presents evidence of travel behavior and related changes from a 6-month field operational test (FOT), during which 195 participants tested the new service. On the basis of the responses to participant questionnaires and interviews and the information recorded in travel diaries, change-enabling service attributes were identified. Such attributes included the transportation smorgasbord concept, simplicity, improved access and flexibility, and economy. Although not a service attribute per se, the FOT also enabled the new behaviors to be evaluated in a trial and a reevaluation of convenience. The broader implications of the findings of the FOT to obtain an understanding of travelers’ new choices and behaviors for the future design of MaaS are discussed. Service design and demand are not independent of each other, and if a mobility service is to change behavior (i.e., achieve an impact) as well as create added value, these goals need to drive design decisions and the deliberate, conscious development of service dimensions, such as customization, bundling, and the range of the offer. On the basis of the experiences gained, the authors emphasize the need for a more holistic and flexible perspective on mobility (and the design perspective on mobility services) that is focused on serving users’ needs and that involves capitalizing on synergies between public and private actors to develop the MaaS offer and better meet the urban mobility challenge ahead.

Airport operators occupy the complex space between managing a major economic generator for their region and operating a piece of municipal infrastructure that generates significant environmental emissions. Airport operators document airport environmental impacts and economic vitality and development, as well as study initiatives to improve in these areas in airport sustainability plans. However, neither airport sustainability planning guidance nor plans in practice document the economic or environmental impacts of air carrier incentive programs, which are municipal and airport-funded programs to waive fees for airlines launching new routes. As air carrier incentive programs (or airline incentive programs) are a mechanism through which airports and cities invest in growth and economic development while contributing to the environmental impacts of their airport, these programs are a natural fit for study within the structure of airport sustainability plans. This study presents a methodology for estimating the air traffic, investment costs, and environmental emissions from new flights launched under airline incentive programs and compares these values with existing economic development and sustainability initiatives documented in airport sustainability plans. It is found that the scope of airline incentive programs is significant in terms of air traffic, costs, and emissions, providing justification for documenting airline incentive programs. How a gap in the understanding of the economic value of incentivized flights hinders a comprehensive evaluation of airline incentive programs is discussed. The lack of a planning process for airline incentive programs keeps airport operators from learning from the experiences of their peers.

Governments face critical decisions on how to spend taxpayers’ money and must weigh priorities and come to these decisions in a transparent and defensible way. A prioritization tool can play a critical role in informing spending decisions, ensuring that decisions are made in the interest of the public good, and bolstering public confidence in elected officials and the democratic process. Ideally, a prioritization tool not only evaluates potential projects against a desired set of policy objectives but also prioritizes potential projects into an implementation plan through the integration of pragmatic considerations. Metrolinx, an Ontario, Canada, provincial agency tasked with transportation planning for the greater Toronto and Hamilton area, developed a prioritization framework to make recommendations on capital investment in sustainable transportation. This paper summarizes the current prioritization framework, outlines its limitations, and goes on to explore potential remedies to those limitations as well as inherent challenges. Specifically, the paper discusses incorporating broader considerations, including multimodal integration and active transportation, congestion, network effects, and project interdependencies, and bridging the gap between project evaluation and real-world prioritization. The paper presents best-practice research for each broader consideration and posits that these broader considerations can be used to transform evaluation outputs into prioritized implementation plans.

Bikesharing systems have been expanding rapidly. They are recognized as a strategic tool to integrate transit and to foster sustainable transportation in urban areas. A critical problem that arises in the planning and deployment of a bikesharing system lies in demand–supply imbalance as the result of the spatiotemporal dynamics of demand patterns. The problem manifests itself in situations in which no bikes are available to rent and no docks are available for bike return at certain popular stations. This study developed a framework for modeling user behavior in response to such situations. Particular emphasis was placed on user on-site choice behavior and the behavioral aspect related to wait time if a decision to wait for the next bike or dock was made. These behaviors were approached with the use of a discrete choice model and a duration model, respectively. Further, a discrete-continuous process was proposed to address the potential interrelation that existed between the choice to wait and the length of waiting time to be endured. Within the developed framework, the models were estimated on the basis of the data from a revealed preference–stated preference survey conducted on the YouBike system in Taipei, Taiwan. The estimation results provided insights into user familiarity and uncertainty toward the system, travel situation, or environment and the associated effects on user behavior of a bikesharing system under a demand–supply imbalance.

California’s Sustainable Communities and Climate Protection Act of 2008, also known as Senate Bill (S.B.) 375, called on metropolitan planning organizations to develop integrated plans for transportation and land use capable of achieving mandated reductions in greenhouse gas emissions. The first round of regional plans conducted under the new law’s provisions is now complete. This research assessed achievements and challenges in California’s four largest regions in advancing sustainability goals through transportation–land use planning integration under S.B. 375. On the basis of an assessment of plan documents from before and after passage of the law, progress was assessed for four aspects of the planning process: development of performance objectives, land use projections, techniques for analyzing plan options, and implementation strategies for encouraging land uses that supported regional plan goals. The analysis indicates that post–S.B. 375 plans demonstrate advances in promoting sustainable transport, for example, in their budget allocations and in attaining performance metrics for location and transport efficiency. Innovative implementation strategies are described, as are emergent conflicts pointing to challenges in reconciling and achieving sustainability goals within the law’s planning framework.

Bike-to-school programs are aimed at improving the daily travel experience and safety for young commuters and constitute an opportunity for behavioral shifts toward sustainable mobility. However, only a few cases of bike-to-school programs have been documented. The lack of information is especially critical in rapidly growing cities of the global south. This study documented a promising bike-to-school program called Al Colegio en Bici, implemented in Bogotá, Colombia. The program began in 2013, after a year of planning, and has provided improved access to public schools to low-income populations and gives children the opportunity to travel safely while using a sustainable mode of transport. More important, Al Colegio en Bici is expected to influence travel behavior in young generations and thus may positively affect health and reduce harmful emissions in the long run. The program and its implementation are described, and this account is expected to help other cities that are considering such programs as part of their plans for sustainable mobility and access to education.

Sustainable transport commonly considers either the interaction between built and natural environments or the interface between transportation and interdependent critical infrastructure. Although considering each of these key dimensions is a crucial task for achieving sustainable transport, the dimensions are infrequently considered together. When an integrated network design framework is proposed, two important issues are taken into account: ( a) the aftermath of potential severe weather episodes on metropolitan-area infrastructure and ( b) the existing interdependencies across transportation and fuel supply chain networks. Then the response of infrastructure in the face of flooding hazards is investigated. Framed within a multistage linear stochastic program, the proposed model seeks to find fueling station deployment that provides the transportation network with optimum random functionality when the network is stressed or under attack. A set of numerical experiments illustrates how changes to enhancement strategies at different stages of government affect the optimal investments in resilient design.

This study investigates the development and performance of an innovative approach to the management of transportation, land use, air quality, housing, and a variety of other regional development issues, called “blueprinting.” Blueprinting refers to a process that brings together planning experts, local political leaders, and ordinary citizens; arms them with current planning ideas about “smart growth” and data visualization tools, to develop long-range regional development plans. As such, blueprinting represents a recent manifestation of regionalist approaches to environmental policy and planning. Focusing on the Sacramento region, an early adopter of blueprint planning, we use archival data and media sources to reconstruct the development of blueprinting and then we turn to an analysis of the performance of the blueprinting approach in relation to three successive planning efforts. We find that despite the promise of blueprinting, very little progress has been made toward actually changing the regional transportation system and land use patterns. The net result of this long-term planning effort aimed at achieving sustainable transportation land use is that total CO2 emissions increase over time at historical rates. We close with a discussion of what this means for regional planning and achieving goals set by California's landmark climate change legislation.

One of the solutions suggested for mitigating the detrimental effect of motor vehicles on society is to implement transit-oriented development (TOD). This type of development is intended to reduce automobile use and urban sprawl as well as to provide communities with more socially, environmentally, and economically sustainable neighborhoods that offer a variety of mobility choices. This study attempted to find out whether new residents adopted more sustainable modes of transportation after their relocation to a TOD. The analysis determined which factors influenced travel mode switching decisions by specifying a multilevel multinomial logistic regression model. Data for the analysis were drawn from a travel behavior survey conducted on residents in seven North American TODs in 2013. The results showed that newcomers adopted more sustainable travel modes for amenities and leisure trips after they relocated to a TOD but that they were less likely to do so for work and shopping trips. To encourage more sustainable travel modes, the study findings suggested that transit incentives coupled with workplace parking charges needed to be considered. Factors that were found to increase the probability that new TOD residents would switch to a more sustainable mode of transportation included their awareness of the environmental impact of each travel mode, the ease with which it was possible to walk through the neighborhood and to various destinations, and the proximity to transit stops. However, larger household size, homeownership, and the addition of a new car had negative impacts. The findings provided new insights into TOD planning and its link to travel behavior; these insights could benefit planners, engineers, and policy makers who have adopted the TOD approach to development with the goal of mitigating car usage.

In the past two decades, Chile has undergone a series of economic and social improvements that have put the country a few steps ahead toward development. For example, Chile has reduced poverty levels by more than 50% in less than 20 years. It is widely recognized that increasing the access of the population to basic services such as health and education is a key factor influencing development. The provision of low-volume roads (LVRs) is essential to offering that access, which should also rely on proper levels of service through sustainable management. The objective of this keynote is to describe Chile's main experiences concerning sustainable management of the LVR network and the challenges Chile will face in the future. Chile's experience with the LVR network can serve as an example for other developing countries in the same way that the country's implementation of the concession model (or public–private partnerships) did for its system of main highways a few years ago.

Federal land managers in the United States, especially in the National Park Service, are becoming more interested in providing opportunities for visitors to experience a unit in the national park system without a private vehicle. Alternative modes of transportation can help park units address numerous challenges, including preserving the resources for present and future generations and enhancing the quality of the visitor experience. One mode of travel that is receiving considerable attention is the bicycle, especially various forms of bikesharing. De Hoge Veluwe National Park, in the Netherlands, has had a bikeshare system since 1975. Federal land managers may be particularly interested in this system because ( a) the bikes are provided without charge, ( b) there are provisions for children, ( c) the bikes are not used to advertise private businesses, and ( d) bicycling is good for the environment and users’ health. This paper briefly reviews the evolution of bikesharing, summarizes studies related to bicycles and pedestrians in the context of federal lands, presents information about De Hoge Veluwe National Park and describes its white bikeshare program, and concludes with considerations, such as unit size and location, for implementing a similar system in the United States. Units that are developing bikeshare systems should consider features that are attractive to potential users, such as a cost-effective pricing system and bicycles for a wide variety of users.

Although activity-based models (ABMs) are starting to be used for metropolitan area transportation planning and policy making, experience is lacking in the use of the wealth of information and measures that such models offer. This paper reports on the implementation of an advanced ABM developed for the Tel Aviv, Israel, metropolitan area to analyze the various transport, activity, and emissions impacts of auto restraint, transit, and land use policies. The policy implications of various scenarios are presented. The results showed that a combination of aggressive pull-and-push measures to encourage more transit and less car use had only marginal impacts on total vehicle kilometers traveled, emissions, and greenhouse gas emissions. Other findings showed no synergic effects and suggested that some policies might have had unintended outcomes. All of the policies tested led to less congestion but increased accessibility at the same time; the increased accessibility attracted more trips to the city. Overall, this study showed that ABMs could provide important advantages in the analysis of various transport policies to improve sustainable transportation development and to enable detailed analyses of the synergic effects of various policies and their impact on many indicators. The paper advances the state of the practice of the use of ABMs for policy analysis, but much more experience and insight are needed on the best way to use the rich information and abundant measures obtained from such models.

Sustainable transportation interventions affect public health in three ways: through ( a) reduced pollution emissions, ( b) increased physical activity, and ( c) reduced road accidents. The public health benefits that can be achieved through investment in sustainable transport thus are substantial. This study sought to estimate benefits from sustainable transport intervention in the city of Indore in the Indian state of Madhya Pradesh through the construction of a bus rapid transit (BRT) system along a main traffic corridor. The benefits were estimated with a health impact assessment methodology developed on the basis of modal shift and vehicle kilometers traveled. With the introduction of a BRT system, the study found that about 14 lives could be saved per year as a result of an increase in walking or cycling, a decrease in private vehicle use, and a reduction in air pollution exposure. Also, more than 96 deaths could be prevented from 2013 to 2017 along the BRT corridor when compared with current trends in motorization with no BRT system investment. The reduction in emissions between a business-as-usual scenario and post-BRT scenario was 11%. The mortality risk from exposure to particulate matter of up to 2.5 mm in size could be reduced by 1.1%. Even given the limitations with respect to the data and the assumptions made in the study, the results were significant enough to recommend that public health aspects be considered in the formulation of transport policy and in the maximization of benefits.

The objective of this study was to develop a framework for real-time emissions modeling to improve ecofriendly intelligent transportation system (ITS) applications. The proposed framework can be utilized for real-time ITS applications, such as ecorouting, and applications for the environment with a real-time information synthesis program. To develop a more efficient framework, a new interface with the motor vehicle emission simulator (MOVES) model was developed to enhance computational performance. In addition, a methodology that used a probe vehicle equipped with onboard equipment was suggested for collecting operating mode distribution through the network to generate input for the MOVES model. Through virtual implementation with a simulation environment developed with the Python scripting language, this study demonstrated that the proposed framework generally worked as designed. The study also investigated the effects of probe vehicle sampling size on estimation accuracy.

Cities in the developing world are experiencing rapid motorization. In Asian cities, the fleets of two-wheelers are growing particularly fast, with electric bikes (e-bikes) driving much of that growth, especially in China, where more than 200 million e-bikes are on the roads. This study aimed to provide elements to further the understanding of the environmental implications of the fast growth of e-bikes by examining their energy efficiency, effect on local air quality, and greenhouse gas emissions. The findings show that e-bikes have a positive environmental performance, with high energy efficiency compared with other transport modes and benefits for public health as a result of zero tailpipe emissions. The findings need to be weighed by the fact that e-bikes have higher accident rates and are a strong competitor for public transport that could threaten the financial sustainability of public transport and reduce its ability to shape the urban form in a more sustainable way.

The Netherlands is often viewed as a world model of urban planning and sustainable transport practices. This article reports on a study which charts the planning policy transfer activity between the Netherlands and other countries. The study reveals that many foreign ‘policy tourists’ are impressed and inspired by Dutch planning achievements. However, policy transfer efforts based on Dutch examples of planning have rarely resulted in concrete actions or hard outcomes abroad. Contextual differences in culture, social setup, language, planning legislation and financial resources, as well as the failure to involve political elites in transfer processes, are potential obstacles to embedding Dutch planning policies elsewhere.

In an effort to make urban transportation more sustainable, policy makers and social marketers have turned increased attention to bicycling. The authors apply behavioral reasoning theory to investigate consumers' mental processing of bicycle commuting to better understand why such an active mode of transportation is underutilized in many urban areas. Using a large-scale sample of commuters in Dublin, Ireland, the study offers insights into the psychological antecedents of bicycling adoption. The structural equation modeling results confirm the main premise of behavioral reasoning theory, in that reasons serve as important linkages between people's values and their attitudes and behavior. In particular, the findings suggest that commuters have reasons not to engage in bicycling (e.g., inconvenience, perceived danger), which account for most of the variance in bicycle-commuting behavior. The findings challenge interventions that emphasize the role of information campaigns and one-time infrastructural changes in encouraging voluntary change in travel behavior. Instead, the findings suggest that transportation planners and social marketers would be better off addressing consumers' reasons for and against bicycling through community-based initiatives.