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The expected electrification of Sub-Sahara Africa's urban paratransit with an electric minibus taxi (eMBT) has received increased attention in energy research and expenditure analyses. In this paper, several long-distance routes between the Western Cape and the Eastern Cape in South Africa are assessed for electrification. To mitigate the long charging time of eMBTs, we propose a battery swapping approach in which a trailer acts as a mobile battery bank to the vehicle (eMBT+T); which is to be charged from a solar charging station to reduce emissions. Compared to the current MBTs, the proposed model results in only a 6% trip time increase. Crucially, emissions are reduced by 75%, where a 20% increase is seen when using an eMBT. The results show that a trailer battery enables viable long-distance electrical paratransit, and with the integration of solar power charging, this transition can also be sustainable. [ABSTRACT FROM AUTHOR]

Although the built environment–travel connection has been extensively examined in urban settings, evidence from rural and small towns is still scarce. This paper addresses this gap by exploring the influence of the built environment on travel mode choice using national-level survey data from 119 rural towns throughout China. The results show that rural built environment variables significantly influence mode choice, with socioeconomic, regional economic and natural environment factors controlled: at regional level, close proximity to county centres, highways and bus stops tend to reduce car dependence. At local level, small-scale, compact, and mixed land use encourage walking and bus use. The built environment influences mode choices for shopping trips more than commuting trips. The results suggest that spatial planning for land use and transport networks will be effective in shaping greener travel and sustainable transport development in rural areas of China and in developing countries with similar contexts. [ABSTRACT FROM AUTHOR]

• Data-driven economic assessment of alternative power technologies for transit buses. • Life cycle social cost model as a tool for policy-making on alternative bus powertrains. • High purchase costs and limited battery range hinder electric bus deployment. • Congested urban routes are the most suitable for electric buses. This paper aims to analyze overall economic and environmental performances of alternative bus powertrains by focusing on U.S. active fleets in different urban contexts. We define a life cycle cost model related to bus technologies by referring to real-world data of 256 transport operators, which provide more than 80% of total vehicle revenue miles produced by urban transit mode across the U.S. in 2019. The proposed method includes some service parameters that significantly affect the supply cost (e.g., service speed, annual mileage), on which we perform scenario and sensitivity analysis. Results show that electric buses are cost-competitive in large cities and metropolises, where urban bus routes are characterized by a high level of congestion, high service frequency, and the highest marginal impact of harmful emissions. In towns and suburban areas, where bus routes are longer and faster, full electric technology still faces both economic and technical barriers. [ABSTRACT FROM AUTHOR]

This paper aims at studying the status of the current fleet of freight vehicles that travel through Uruguay, following international methodologies for calculating GHG gas emissions to determine the current inventory of gases caused by road freight transport. This inventory acts as a starting point to establish three future scenarios where different alternative powertrain technologies are implemented at different rates, such as battery electric vehicles (BEV) and fuel cell electric vehicles (FCEV). The transition from Euro III regulations into Euro V is also considered for these scenarios. Based on these future scenarios, it is possible to project the levels of future emissions that Uruguay will perceive in a time horizon that reaches the year 2050. This study aims to increase the level of information present in the region on the emissions generated in the road freight transport sector, providing new input to the development of future policies on these issues. [ABSTRACT FROM AUTHOR]

Emissions from real-world driving are often higher than estimated emission levels based on Euro emissions standards and type-approval tests. Consequently, the air quality in cities has not improved as originally anticipated from fleet renewal and stringent emission regulations for newer vehicles. This paper presents the real-world emission factors (EFs) for in-use cars, taxis, vans, and buses obtained using on-road remote sensing in Dublin city, Ireland. EFs from both petrol and diesel Euro 6 vehicles were significantly improved compared to the EFs of older emission standard vehicles. The analyses indicated that the presence of a few high emitting older vehicles skewed the overall distribution of EFs. Detailed description of variations in EFs for individual pollutants based on changes in emission standards, location, and other driving characteristics were studied and reported, which provide justification for implementing policies targeting fleet renewal. • First study to report real-world emission factors for in-use vehicles in Ireland. • This study considers cars, taxis, vans, and buses of varying makes and models. • Decreasing trends of NO EFs for all diesel vehicles with higher Euro standards. • Strong temperature dependence of NO x emissions for Euro 4 and Euro 5 diesel cars. • Remote sensing measurements can be used to inform vehicle emission control policies. [ABSTRACT FROM AUTHOR]

This paper details how instantaneous vehicle emissions, namely, CO 2 , CO, NO X , and HC from light-duty vehicles, can be predicted using the integrated deep neural network method (NNM). The deep-learning algorithms, i.e., short-term memory (LSTM), gated recurrent unit (GRU), and recurrent neural network (RNN) methods, were applied to predict the emissions. Finally, an integrated method using LSTM, RNN, and GRU was used to determine if the integrated method was better at increasing the prediction performance of vehicle emissions. Each model performance was evaluated by calculating the mean squared error (MSE), root mean squared error (RMSE), and normalize root mean squared error (nRMSE) values. The results indicate that the integrated LSTM NNM provided the best overall emission prediction compared to the other methods. This integrated model can help to develop new policies and regulations for vehicle emissions. • Instantaneous vehicle emissions, namely, CO 2 , CO, NO X , and HC, were predicted. • Integrated deep neural network method applied to improve the prediction performance. • Integrated methods were compared with the deep neural network algorithms. • Model performances were evaluated. • The integrated LSTM method provided the best overall emission prediction. [ABSTRACT FROM AUTHOR]

• A data-driven approach to deploying charging facilities for electric buses (E-buses). • A real-world bus trajectory dataset used to quantify charging demand at the micro-scale. • Wireless charging lanes can greatly improve level of service with a slightly higher cost. • Parameters related to E-buses and charging facilities were influential to model outputs. This paper developed a data-driven micro-simulation optimization model to deploy charging infrastructure for a large-scale electric bus network, considering both traditional charging posts and wireless charging lanes (WCLs). The optimization model has two objectives: 1) minimize the total system cost and 2) maximize the level of service. We used New York City as the study area, and one-day GPS trajectories of 3,133 buses were analyzed to develop the micro-simulation approach, so as to represent the bus operation well. The results showed that the scenario with both charging posts and WCLs deployed had a significantly higher level of service (with its total delay time being 48.11% shorter), more energy saved and fewer emissions than the scenario with only charging posts deployed, though its total cost was 0.76% higher. Moreover, the sensitivity analysis results show that the parameters associated with electric buses and charging facilities could heavily influence the outputs of interest. [ABSTRACT FROM AUTHOR]

This paper investigates how carriers adapt to the sulphur regulation by choosing between sulphur scrubber (SS) and fuel switching (FS). A cost minimization model is proposed to determine the optimal compliance choices, considering factors such as fuel prices, capital cost difference between SS and FS, and shipping service profile. We find that the optimal choice depends on the tradeoff between the capital cost advantage of FS and the fuel cost advantage of SS. And such a tradeoff is moderated by the vessel's annual fuel consumption. Ignoring the speed differentiation behavior of FS vessels would exaggerate the benefits of SS. But whether it can cause a wrong compliance choice depends on the extent of overestimation, which depends on the presence in emission control areas and fuel prices. When fuel price volatility is factored in, a portfolio of FS and SS might be better than simply choosing either one for all vessels. [ABSTRACT FROM AUTHOR]

Micro-mobility vehicles (MMVs), including a range of small-size and light-weight vehicles such as (e-)bicycles and (e-)scooters, are becoming more popular and widely used, which also brings a challenge to the efficient and safe utilisation of road infrastructure. Especially, the coexistence of pedestrians and MMVs in a space sharing context raises many concerns on road safety. This paper provides a systematic review of relevant studies on the interactions between pedestrians and MMVs in shared spaces. The most investigated factors include infrastructure features (e.g., road environment and regulations), road users' characteristics (e.g., demographic information and behavioural norms), and operation conditions (e.g., dynamic factors and traffic features). Our findings suggest that space sharing could be encouraged for pedestrians and MMV users. More efforts are needed on multi-source data collection, processing, and application. Further investigations need to focus on multiple types of MMVs, high-density conditions, emergency conditions, MMVs' parking issues, and MMVs' functions. [ABSTRACT FROM AUTHOR]

Sweden has set itself aspirational climate goals to reduce its fossil fuel dependence, and has the ambition of being a global climate transition leader. These goals have proven difficult to achieve in the transport system. In this paper we describe the development since 2016 of a broad and heterogeneous discourse coalition in favour of more strategic governance in Swedish transport planning, encompassing business, trade unions, environmental experts and green-left politicians. We first analyse their claims for a radical reorientation of Swedish transport planning, which are shown to focus on fiscal rules, a lack of political courage, and slow-moving environmental legislation processes, as three main reasons why the transport system is slow to transition. We then discuss whether these claims constitute a politicisation of the climate policy discourse, or rather a new iteration of the previously depoliticised discourse. [ABSTRACT FROM AUTHOR]

• Traffic data are retrieved from vehicle detection systems for the 2019 Kincade fire. • Relationships for speed, density and flow are benchmarked with routine traffic. • Evacuation speeds are lower than routine speeds in the low and high-density range. • Traffic models need to use updated relationships for wildfire scenarios. Traffic models are a useful tool for evacuation planning and management in case of wildfires. Despite the availability of several evacuation models, the number of datasets that can be used for their calibration and validation is limited. This paper presents key traffic flow data collected during the 2019 Kincade Fire. The data (69 116 data points from 24 locations) have been sourced from the Performance Measurement System of the California Department of Transportation. A set of commonly used models that describe the relationships between speed, flow and density has been fit to the data and compared to the model from the Highway Capacity Manual. In evacuation scenarios, the vehicle speed is about 3.5 km/h lower in comparison with the speed in routine scenarios, both for low and high traffic density. This demonstrates that dedicated models are needed for an accurate estimation of traffic evacuation times. [ABSTRACT FROM AUTHOR]

Although operational activities in the aviation sector inevitably bring more emissions, they also reshape the structure of the regional economy, and often upgrade emission-heavy industries to cleaner service sectors. Thus, the overall impact of aviation network development on the region's environmental trajectory is unclear, and calls for rigorous empirical study. Using the data of 283 Chinese prefecture-level cities for the period 2003–2017, this paper proposes and calculates a comprehensive "carbon lock-in" index to measure cities' reliance on emission-heavy sectors and resistance to emission reduction. Then, we calculate cities' air connectivity and network centrality to measure the aviation development, and also examine their direct, indirect, as well as heterogeneous impacts on cities' carbon lock-in. Our empirical results suggest that an improved aviation network development helps alleviate carbon lock-in. Mechanism analysis further reveals that fixed input, industrial structure upgrading, and technological innovation are the three underlying channels. [ABSTRACT FROM AUTHOR]

This research conducts a comprehensive review on the social impacts of Cooperative Automated Driving (CAD), including Infrastructure Enabled Autonomy (IEA). In order for reviewing and summarizing the CAD-related literature in an explicit and logical manner, this research originally classifies literature according to the Cooperative Automation Classes released by SAE. Based on this classification, the research progress of CAD in each class is briefly introduced, involving the objectives, contributions, and challenges of existing CAD studies. Furthermore, the social impacts of CAD on safety, mobility, and sustainability are analyzed, including the investigation into the potential of CAD in performance improvement, the discussion on the reliability of existing research results, and the summary of the key factors influencing the benefit fluctuation. The research results indicate that the benefits of adopting CAD are significant, while with the rise of CAD class, a more significant improvement could be observed. At the end of the paper, the challenges and opportunities for CAD are also summarized, and future studies on CAD are provided. [ABSTRACT FROM AUTHOR]

[Display omitted] This paper presents a comprehensive review on the most recent level of knowledge and developments achieved in utilizing photocatalytic asphalt pavement as a method to reduce vehicle pollutants. It included the mechanism of photocatalysis, available testing facilities, quantifying methods, widely studied techniques of applying TiO 2 particles onto asphalt pavements, influencing factors on pollutants degradation and future perspectives. Nano-TiO 2 crystal types, doping approach, ambient temperature, relative humidity, intensity and time of irradiation, and pollutant characteristics are the key factors that influence the efficiency and durability of photocatalytic asphalt pavement. The photocatalytic asphalt pavement can achieve a degradation efficiency of 55% for NOx pollutants and 20% for SO 2 pollutants at this moment, while suffering from short service life due to busy traffics and complex weather circumstances. In the future perspectives of photocatalytic asphalt pavement, practical costs, applying methods, durability, and negative effects are highly emphasized for the development of sustainable and durable photocatalytic roads. [ABSTRACT FROM AUTHOR]

• Review the characteristics of disabled travel and its relationship with urban environment. • People with disabilities make fewer and shorter trips, drive less, and rely more on transit and non-motorized modes. • People with disabilities make travel decisions to maximize utility under physical, financial and psychological constraints. • The travel behavior of people with disabilities is affected by built and social environments. The relationship between urban environment and the travel of people with disabilities has received scholarly attention. Studies have analyzed disabled travel from multiple perspectives. However, there lacks a systematic review of the variety of existing research methods and results. This paper identifies and examines 66 studies to understand the state of knowledge on the relationship between urban environment and the travel of people with disabilities. Adapting the classic travel demand model to the mobility characteristics of people with disabilities, we interpret the existing literature, point out the missing links, and suggest directions of future research. [ABSTRACT FROM AUTHOR]

This paper aims to explore the contribution of slot allocation to noise abatement at schedule coordinated airports. To this end, we first build a single-airport bi-objective model that incorporates scheduling efficiency and noise reduction. We then find and analyze a solution that maximizes airport noise reduction with the greatest allocation efficiency. The price of noise reduction is proposed to gain the trade-off between efficiency and environmental benefits. Our research shows that slot scheduling can reduce noise at Shanghai Hongqiao International Airport. The maximum noise reduction schedule shows high fluctuation in the temporal distribution of slots. The price of noise reduction is very high under the maximum noise reduction schedule, and the required displacement to reduce one unit of noise increases sharply as the noise reduction value rises. Besides, the airport capacity expansion plays an essential role in reducing the price of noise abatement. [ABSTRACT FROM AUTHOR]

• A BEB energy consumption model based on characteristic data is developed. • A simple method to extract characteristic data from unordered data is proposed. • A BEB charging plan schedule optimization model is developed. • The energy estimation error is analyzed in the BEB charging schedule model. With the increasing of Battery Electricity Bus (BEB), the orderly charging of buses becomes more and more important. This paper formulates a battery electric bus energy consumption model based on characteristic data, and proposes a simple method to extract the characteristic data from the unordered data. A simple and practical BEB charging plan schedule optimization model based on BEB fleet's departure plan timetable and trip electricity consumption estimation is developed. Given some realistic assumptions, the schedule model is formulated as a mixed integer linear model. The objective function can accurately calculate the charging cost in a linear manner. Only two kinds of constraints are included in the model, they can ensure each BEB journey is feasible. The real-world numerical tests show that: in the simulation cases, the average relative error of the energy consumption model is 7.5–9.2% and the optimized charging plan could reduce the charging cost by about 16%. [ABSTRACT FROM AUTHOR]

The environmental problems brought by the shipping industry have drawn the attention of all parties, making it critical to select a fuel system that combines economic and environmental benefits when ordering new ships. This paper narrows down a list of fuels to four high-potential options: LNG, methanol, hydrogen, and ammonia. Based on the dual perspectives of shipowners and the public, this study takes different-sized ships as the object, establishes mathematical models throughout their life cycle, and selects a variety of indicators to evaluate alternative fuels. The findings demonstrate that, in the short term, heavy fuel oil with scrubbers is the most economically advantageous option for all sizes of container ships, but methanol is a desirable alternative when taking into account the social cost of pollutants. Hydrogen might be the ultimate fuel to reduce emissions in the long run when the price gap closes. [ABSTRACT FROM AUTHOR]

This paper considers one class of scheduling problems involving interdependent improvement projects that aims to restore disruptions in transportation systems, and beyond. Two key features of this class of restoration scheduling problems are the timing component, i.e. not all projects can be carried out at the same time, and the interdependency of the improvement projects. That is, the benefit of an improvement project, and possibly its cost, depends on whether another project has already been implemented. An elegant and exact solution method will be presented. Examples are provided to demonstrate how the method can be used to help transportation systems recover from disruptions. Model extensions to cover new disruption scenarios are also presented and discussed. [ABSTRACT FROM AUTHOR]

• A framework for bridge scour risk management in an uncertain climate future. • A systematic approach to estimating scour risk ratings in different climate scenarios. • Local scour progression is fastest during the initial 48 h of a peak flow event. • Accelerated scour risk progression even in low emission climate scenario (RCP2.6). Riverine bridges are under a substantial threat of scour due to the magnitude and frequency of floods arising due to climate change. Infrequent inspections, inadequate data on foundation depths, and the lack of consideration of hydrologic and climate parameters often result in uncertainties within current scour risk assessments. This paper presents an approach for assessing the risk progression of local scour in peak flow conditions that consider uncertainties associated with location, downscaling of climate predictions, and hydrologic, hydraulic and scour prediction models. A rational scour risk rating based on warning time to failure is introduced that can provide a useful addition to the existing bridge condition indexes. The case study on a set of railway bridges in Southeast England shows that climate change could accelerate the scour risk progression, even in the low-emission scenario. The approach and results form a vital basis for scour risk mitigation and climate adaptation planning. [ABSTRACT FROM AUTHOR]

• We study the Carbon Offsetting and Reduction Scheme for International Aviation. • We compare the equity of five carbon offsetting mechanisms. • Countries may have conflicting interests in the current mechanism. • We use preference score compromise method to balance the interests of countries. This paper compares the offsetting responsibilities of countries under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) and four equity principles, that is, historical responsibility (HR), ability to pay (AP), equal per capita emissions (EP), and emissions intensity (EI). We also use the method of preference score compromise (PSC) to design a commonly acceptable compromise mechanism. We find that, first, the USA, the UAE and China will be affected most if the mechanism is changed from CORSIA to another. Second, CORSIA is a good choice for the USA, Germany, France, and Australia, while other countries with the highest revenue tonne kilometers in international aviation may have strong motivations to change from CORSIA to AP or EP. Third, EI does not bring the lowest cumulative offsetting costs for any country, but is most similar to the compounding mechanism under PSC. Finally, some policy implications are provided. [ABSTRACT FROM AUTHOR]

We address the situation where required times of arrival (RTAs) are assigned outside the feasible time window that allows aircraft to fly energy-neutral continuous descent operations (CDOs). Two strategies to achieve these RTAs are compared by means of simulated optimal trajectories and in terms of fuel consumption: powered descents along the published arrival route vs. energy-neutral CDOs along re-negotiated routes. A sensitivity study to different parameters led to results primarily for RTAs later than the estimated time of arrival. With strong-tailwind, stretching the route and flying neutral CDOs improves the efficiency of the operation. Light aircraft also benefit from being assigned longer pre-defined routes, while for heavy aircraft it is more efficient to fly powered descents along the published route. This paper could contribute to enhance ground-based decision support tools for air traffic controllers, aiming to manage arrival traffic more efficiently and reducing the overall environmental impact of arrival operations. [ABSTRACT FROM AUTHOR]

• Comprehensive methodology for evaluating intermodal transport chains. • Case study for evaluating various transport chains to Northern Europe. • Identification of the impact of external costs in the transport chain preferences. • Geographical information system utilization for displaying chain preferences. This paper presents research on the impact of transportation external costs internalization in the competitiveness of short sea shipping. Numerical methods for calculating emissions and external costs, that consider the full range of technical and operational vehicle characteristics are presented. The impacts of existing and future emission control areas, emissions abatement technologies, types of fuel, ship speed, cargo capacity and utilization factors in the required freight rate are evaluated. Internal and external costs are used to evaluate alternative intermodal chains for a set of pairs origin/destination extending to a range of regions in Northern Europe. Short sea shipping is competitive for a large set of destinations and its scope of competitiveness does not change significantly between different scenarios. Competitiveness regarding external costs shows more variation but, due to the small relative magnitude of these costs, internalization shows a moderate potential for promoting modal shift towards short sea shipping. [ABSTRACT FROM AUTHOR]

Searching for a new eco-friendly marine fuel has become necessary to eliminate the adverse effects arising from ships' emissions. The current paper investigates using blue/green ammonia as a marine alternative fuel from environmental and economic points of view. A new RO/RO vessel under construction is investigated as a case study. Three propulsion systems are considered: heavy fuel diesel engine, blue/green ammonia diesel engine and blue/green solid oxide fuel cell (SOFC). Environmentally, SOFC green ammonia-fueled ship is the best selection with NO x and greenhouse gas (GHG) emissions' reduction of 93.4% and 92% compared with the traditional propulsion system. Economically, SOFC blue ammonia-fueled ship will be the best selection with total ship saving cost of 5.71% and annual levelized cost of energy 0.19 $/kWh. Finally, SOFC green ammonia-fueled ship proposes to be eco-friendly with cost effectiveness of 172.92 $/ton-emissions as a step forward to achieve IMO 2030 strategy. [ABSTRACT FROM AUTHOR]

The available truck Global Positioning System (GPS) data, typically collected with large time gaps, rely on imputation techniques to obtain second-by-second data that are required in models for estimating truck energy consumption and emissions. However, existing speed imputation techniques either require a large amount of high-resolution data for model training or rely on special movement assumptions. To fill the gap and effectively apply the low-resolution truck GPS datasets, this paper proposes a simple imputation technique that adopts the Brownian bridge structure to impute missing speed data. The proposed technique introduces a feasible imputation region and a combined drift into the imputation procedure to capture vehicle acceleration constraint, travel distance constraint, and speed volatility. The calibrated model is applied to a set of low-resolution truck GPS data. The results demonstrate the robustness of the proposed technique in enhancing estimation accuracy when using low-resolution GPS data to estimate fuel consumption and emissions. [ABSTRACT FROM AUTHOR]

This paper provides insight into motivational reasons for consumers' preferences for Electric Vehicles (EVs) assuming equal and different prices between EVs and traditional vehicles. Referring to consumer behavior, it shows that reputation-driven consumers prefer EVs only when the purchase price is more expensive than that of other vehicles, thus suggesting that true environmental concern is attenuated by reputation motives; and that the desirability of EVs as sustainable products only increases if prices are more expensive. It provides insights into the influence of sociodemographic variables, car attributes and external environmental factors. The study offers an empirical approach with a sample set of more than 2.000 responses. Different logit models are estimated to explore the factors influencing the preference for an EV. It is found that age, being male, having children, education, living in urban areas, and previous experience positively influence EV adoption. Better infrastructure and information availability help to promote EVs. [ABSTRACT FROM AUTHOR]

The urbanization of China is changing from incremental growth to urban intensification, and urban compactness is a significant attribute for measuring the intensified degree of regional space and societal frameworks. We carefully outline the inadequacies of compactness measuring methodologies and associated research, and argue that compact cities and metro systems contribute to urban sustainable development in tandem. Thereby, this paper investigated 27 strategic region of metro stations on Chengdu Metro Line 1 and proposed a novel urban compactness model in three-dimensions. The result demonstrates that the old urban area before the development of the metro system and the new town thereafter have extreme compactness outcomes, resulting in significant contrasts in morphology and intensification indices. This study investigates the correlation and interaction processes among compactness, morphology, and intensive multiple variables in order to give theoretical and practical support for the intensification design of these two regions in Chengdu. [ABSTRACT FROM AUTHOR]

This paper describes the results of an experimental campaign carried out on three urban buses fuelled by natural gas, aimed at measuring pollutant emissions and fuel consumption in real driving conditions. The buses, used for public transport in three Italian cities, were equipped with a Portable Emission Measurement System. Emission tests were performed over the routes on which the buses operate in their service, and cold start emissions were also investigated. The results showed that the differences in CO and NOx emissions can be attributed to the calibration of the fuel supply system. PM emissions were low and similar to those reported in the literature for other CNG buses, while CO 2 and fuel consumption were affected by the driving cycle. Cold start strongly impacted CO and NOx emissions because of the effect of temperature on catalytic converter efficiency, with cold over-emissions strongly dependent on ambient and coolant temperatures at engine start. [ABSTRACT FROM AUTHOR]

• Noise reduction directly improves the health and well-being of residents. • Use of low-noise pavements has a noticeable effect on the acoustic climate. • Noise reduction methods that do not alter the existing landscape are most desirable. • Increased resident satisfaction strongly depends on the noise reduction value. This paper presents an assessment of the effectiveness of low-noise road pavements, as well as impressions of the inhabitants concerning the influence of this solution on their comfort of life. Residents were surveyed before and after the new pavements were installed to determine their subjective opinion of the change in acoustic impact caused by traffic. Moreover, a high annoyance index was used to illustrate the impact of noise reduction on the health of people living in areas adjacent to the analysed road sections. The aim of this study is to compare the subjective perception of noise reduction by residents due to the use of low-noise pavements with the objective form of assessment, which is the analysis of the high annoyance index and the value of road noise reduction. The results obtained show a significant improvement in the subjective perception of the residents after the implementation of the new pavements. [ABSTRACT FROM AUTHOR]

Transit-oriented development (TOD) has been widely introduced in the Global South countries and drawn growing scholarly attention. This paper critically reviews and concisely summarizes the research findings pertaining to the travel, equity and wellbeing impacts of TOD in the Global South. We identify 53 relevant studies and find that TOD increases public transportation ridership and promotes subjective well-being. However, similar to what happens in the Global North, TOD in the Global South also induces gentrification and unexpected social inequalities. We call for more critical and theoretical discussions about the uniqueness of TOD in Global South and application of more sophisticated methods and more detailed indicators to better explain the impacts of TOD. Future studies may also be fruitful to investigate some new topics, such as the role of state in TOD-induced gentrification, residential dissonance in TOD areas and hedonic adaptation to the improvement in transit services. [ABSTRACT FROM AUTHOR]

It is important to understand real-world performance of fuel-saving technologies for heavy goods vehicles (HGVs). This paper concerns applying data mining to quantify the fuel-saving benefit of a low-rolling-resistance (LRR) tyre using in-service operational data. Two HGVs of the same specification were employed, with one using LRR tyres and the other conventional tyres. A smartphone-based data logger was developed to collect data from the HGVs' operations on publics roads for three months. Data from vehicle Controller Area Network, smartphone sensors, weather and elevation databases were collected. A data mining methodology was developed to mine data segments representing dynamically similar driving conditions between the two HGVs, and compare their fuel consumption rates through fitting data to a theoretical vehicle fuel consumption model. It was found that at a 95% confidence level the LRR tyres exclusively brought about a fuel-saving benefit between 6.89% and 8.37% in typical UK motorway driving conditions. [ABSTRACT FROM AUTHOR]

Electric hybrid powertrain and natural gas fuel for spark-ignition engines are among the much promising technologies to reduce the fossil fuel use for road transportation and the emissions of harmful and greenhouse gases. This paper investigated gas and particulate real emissions of hybrid and natural gas passenger cars. On road testing were carried out along urban, rural and motorway routes in Napoli (Italy), by using portable emissions measurement systems. Hybrid vehicle has the main advantage of fuel saving in urban environment due to large use of pure electric mode operation at low speed and load. On the other hand, continuous engine restarting causes peak emissions due to a longer light-off time of aftertreatment systems. By analysing the Vehicle Specific Power, it was observed that at same positive values of power, natural gas vehicle is characterized by lower emission and fuel/energy consumption rates compared to the hybrid vehicle. [ABSTRACT FROM AUTHOR]

This paper analyzes the energy replacement potential for high-speed passenger vessels. Emphasis is on whether better planning of services can mitigate technical and economic barriers to zero emission transport. A novel Mixed-Integer Programming problem for battery electric vessel services that jointly minimizes operator and passenger costs subject to strategic (fleet selection and land-based infrastructure location), tactical (frequency), and operational decisions (sailing pattern) is proposed. The planning problem is utilized to estimate technology replacement potential and associated costs for two existing services/routes in Norway and based on four hypothetical demand scenarios derived from the same two services. The results showcase that constraints related to battery range and charging limit the replacement potential and make energy conservation more pertinent. Abatement cost estimates range between 3 000 and 18 000 NOK per ton CO 2 , placing them well above the social cost of carbon calculated at 2 000 NOK per ton by 2030. [ABSTRACT FROM AUTHOR]

Autonomous bicycles have recently been proposed as a new and more efficient approach to bicycle-sharing systems (BSS), but their environmental impacts remain unresearched. Conducting environmental impact assessments at an early technological stage is critical to influencing the design and, ultimately, environmental impacts of a system. Consequently, this paper aims to assess the environmental impact of autonomous shared bikes compared with current station-based and dockless systems under different sets of modeling hypotheses and mode-shift scenarios. The results indicate that autonomy could reduce the environmental impact per passenger kilometer traveled of current station-based and dockless BSS by 33.1 % and 58.0 %. The sensitivity analysis shows that the environmental impact of autonomous shared bicycles will mainly depend on vehicle usage rates and the need for infrastructure. Finally, this study highlights the importance of targeting the mode replacement from more polluting modes, especially as traditional mobility modes decarbonize and become more efficient. • Autonomous bicycles have been proposed as a new approach to bicycle sharing systems. • The impacts of new mobility modes should be assessed at an early technology stage. • Autonomy could reduce the environmental impact of current bicycle-sharing systems. • Vehicle utilization and infrastructure needs will have the most significant impact. • As other vehicles decarbonize the mode-shift should focus on the most polluting modes. [ABSTRACT FROM AUTHOR]

The EU 'Fit for 55' package proposes the adoption of various legislative tools to eliminate shipping CO 2 emissions, among which are the inclusion of shipping in the EU Emissions Trading System (EU ETS) and the FuelEU Maritime Initiative. This paper analyses the latter by utilising the EU's Monitoring, Reporting, Verification (MRV) database to evaluate the fuel types used, fuel consumption and CO 2 emissions of ships operating within the European Economic Area (EEA) for 2020, the Initiative's baseline. Forecasts of potential future pathways for alternative fuel deployment are then developed that could be used to achieve compliance with the limits set by the FuelEU Maritime Initiative. The results of this study provide significant input to maritime stakeholders and policy-makers on the potential impact of the Initiative for the uptake of clean marine fuels and the contribution of the maritime sector to a climate neutral Europe by 2050. [ABSTRACT FROM AUTHOR]

[Display omitted] The evaluation of environmental impacts for low-noise roads is a challenging topic in life cycle assessment (LCA) due to noise reduction considerations. This paper presents hybrid modifications of conventional LCA, using acoustical pavement characterization data from the close proximity (CPX) test, and models of noise emission, propagation and exposure to incorporate the inventories and impacts of road traffic noise. Furthermore, based on the system and indicators considered in LCA, the monetarization of direct and external costs of low-noise roads was included, in order to extend environmental interpretation to a monetary perspective. The modified LCA was applied in a realistic road test section, comparing (1) traditional stone mastic asphalt (SMA) with low-noise semi-dense asphalt (SDA) surfaces, and (2) different strategies for using SDA. The results of the test section indicated the significant role of road traffic noise in human health impacts, that translate to economic benefits for using low-noise pavements. [ABSTRACT FROM AUTHOR]

Transit users' travel satisfaction is important for assessing the performance of transit-oriented development. Existing studies emphasize the role of service attributes, built environment, and travel attitudes in predicting transit users' travel satisfaction. However, few studies have jointly examined the effects of environment and attitudes based on sophisticated theoretical foundations. This paper aims to narrow this gap by examining the interaction effects of transit accessibility and attitudes towards transit on transit users' travel satisfaction from a person-environment fit perspective. The data is from a household survey conducted in Shanghai in 2018. Using polynomial regression analysis with response surface methodology, the study finds that interaction effects significantly influence the affective component of travel satisfaction, but not the cognitive component. Public transit users' travel satisfaction increases with the congruence between attitude and accessibility. Dissonance is not necessarily a bad situation and may improve travel satisfaction when there is an increase in either factor. [ABSTRACT FROM AUTHOR]

This paper uses data from the 2017 National Household Travel Survey to examine whether Black and Latino trip makers who live in segregated metropolitan areas are required to make longer duration or longer distance trips than their White and non-Latino neighbors. It finds that residential segregation contributes to Black-white and to Latino/non-Latino travel disparities in noticeable but not always expected ways. For those living in racially segregated metropolitan areas, driving to work and play requires additional time for Black trip-makers than for White trip-makers. For Black tripmakers who take the bus to work or to make social or recreational trips, living in a more segregated metro area is associated with shorter trip times. Latino residents of metro areas segregated along Latino/non-Latino lines take longer to ride the bus or walk to work—but not to drive—than Latino residents of less segregated metro areas. [ABSTRACT FROM AUTHOR]

• Non-linear cost optimization model to allocate dynamic wireless charging facility. • Sensitivity analysis of parameters while maintaining minimum state-of-charge level. • Case study of Auckland motorway network to design wireless charging lane assignment. • DWC lane utilization based on initial SOC level and lower threshold SOC level of EV. It is widely recognized that electric vehicle (EV) users get frustrated by the limited range of EVs, slow charging, and limited charging facilities available in the vicinity of their journey route. These factors contribute to slowing down the uptake of EVs. Dynamic wireless charging (DWC) system has the potential to offer a cost-effective solution to these issues. This paper investigates the DWC allocation problem from the decision makers' perspective to minimize individual users' costs as well as the investment cost for DWC facilities. We propose a mixed-integer optimization model to achieve a cost-effective solution for the optimal placement of DWC facilities on the large road network while maintaining an acceptable state-of-charge level. Sensitivity analysis is conducted on the optimization model parameters to check the feasibility and significance of model solutions for DWC placements. The results provide useful insights into the optimal settings of DWC facilities under multiple route environments. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to revisit speed optimization and speed reduction models for liner shipping in a multi/flexible fuel context with regards to the current ongoing speed limit debate at the International Maritime Organization (IMO). The focus is mainly on analyzing the influence of a maximum average speed limit on the optimal speeds, carbon intensity and emissions in conjunction with fleet deployment for dual fuel (DF) Neopanamax container vessels utilizing liquefied natural gas (LNG). [ABSTRACT FROM AUTHOR]

The innovations in battery technologies facilitate worldwide bus electrification, which can conserve energy and reduce emissions. This paper studies the long-term bus electrification that simultaneously optimizes the charging infrastructure deployment and bus fleet transition. The seasonal differences associated with battery capacities, bus lines, and bus timetables are considered. The studied problem is modeled as a mixed-integer linear programming formulation, in which the detailed charging schedules are determined to give the charging location and charging time. The objective minimizes both the cost and emissions. The proposed formulation is tested on a real-world case study. The computational results indicate that replacing DPBs with BEBs can save 17.8% of total cost and decrease 39.3% of carbon dioxide emission. Compared with designing a plan for each period separately, implementing long-term bus electrification can save 13.5% of total cost and 21.7% of operational cost. Moreover, the benefits of implementing long-term bus electrification are more remarkable when the planning horizon is longer. [ABSTRACT FROM AUTHOR]

Structural socio-economic and institutional limitations can affect the implementation of cycling infrastructure. More stringent cycling infrastructure standards aiming to solve deficiencies might exacerbate disparities, especially in poor districts with fragmentary governance. Using an audit and quantitative and spatial analysis of cycleways, this paper examines to what extent structural inequalities and governance issues affect the availability and quality of cycling infrastructure, considering new indicative and normative standards aiming at improving cycling infrastructure in Santiago, Chile. Our results show that the distribution of cycleways is unequal and only partially complies with national quality standards. All districts in the city have both high and low standard bicycle lanes, but since district finances have huge differences, this can lead to inequalities in cycle coverage and districts' capabilities to address current standard problems. This raises relevant challenges regarding governance and how to ensure an equitable distribution of cycling infrastructure in Global South cities. [ABSTRACT FROM AUTHOR]

Traditionally, vessel air emissions are monitored onboard vessels or at fixed points at sea. These methods are not cost-effective for implementing emission control laws that address air pollution monitoring of vessels travelling over a large body of water. Unmanned aerial vehicles (UAVs) equipped with pollution monitoring sensors are becoming a research focus. However, due to battery capacity constraints, the monitoring scope of UAVs is still not optimal. Thus, using a ship (such as a patrol ship) as a UAV mobile supply base can overcome battery limitations and increase monitoring coverage. This paper investigates the joint routing and scheduling problem of ship-deployed multiple UAVs (SDMUs) for the monitoring of pollution from vessels. The artificial bee colony (ABC) algorithm based on simulated annealing is employed to minimize the total monitoring time. The model and solution algorithm are verified by real-time dynamic vessel data from Tianjin Port. [ABSTRACT FROM AUTHOR]

Companies obtain insight into experiences and expectations of stakeholders through social media (SM), where users openly express their opinions and feelings. Shipping companies also extensively use SM to engage stakeholders. Having better engagement is directly influenced by to what extent SM posts touch on the emotions and cognition of stakeholders. This study aims to identify the perspectives and sentiments of stakeholders on Arctic shipping routes (ASR) and to explain the emotional and cognitive standings of stakeholders about ASR. The results show that majority of practitioners are against ASR, and they position this issue as an environmental dilemma in their minds. Also, environmental considerations, companies' behaviors & attitudes, and policy themes dominate practitioners' minds. The current paper is the first that identifies the feelings and opinions of stakeholders towards ASR. The findings have the potential for shipping companies to clarify first their Arctic policies and second their SM-based engagement strategies. [ABSTRACT FROM AUTHOR]

This paper presents a new optimisation model for restoring a multimodal transportation network disrupted by a catastrophic disaster. The model provides an integrated decision of restoration activities by considering the interdependencies of the road network and multimodal terminals for sending relief goods. A new particle swarm optimisation is proposed to determine the number of repair teams for the road network and restoration activities at the terminal. The problem of road restoration is addressed by presenting a new variant of dynamic programming and a greedy heuristic. The model was applied to a multimodal transportation network that was struck by the earthquake and tsunami. The optimal solution considering multimodal restoration decisions has been found to reduce the unsatisfied demand. The proposed particle swarm optimisation and greedy heuristic offer stability in searching for optimal solutions, whereas the proposed dynamic programming can provide an optimal solution with lower computational time. [ABSTRACT FROM AUTHOR]

• Nonlinearity between the built environment and metro-integrated ridesourcing use is analyzed. • Metro-originated and metro-destinated usage are discussed separately. • Employment density has a significantly positive effect on weekday metro-originated usage. • The distance to metro stations shows an effective range. Although ridesourcing has served as an emerging feeder mode to the metro system to solve the first/last-mile issue, research on metro-integrated ridesourcing usage is rather limited. This paper applies a gradient boosting decision tree (GBDT) method to investigate the nonlinear relationship between the built environment and metro-originated and metro-destinated usage, using ridesourcing trip record data. The results show that built environment factors (i.e., density, diversity, and destination accessibility) have significant nonlinear and threshold effects on the integrated usage, which differentiate between weekdays and weekends. Different patterns are also observed between metro-originated and metro-destinated usage. Employment density has a more significantly positive effect on weekday metro-originated usage than metro-destinated usage. The distance to metro stations does exist an effective range. These findings could help not only transportation network companies optimize ridesourcing services but also transportation planners formulate tailor-made land use interventions to facilitate intermodal mobility. [ABSTRACT FROM AUTHOR]

Figure. Graphical abstract (LCS = low-cost sensors; Ref = reference; AQ = air quality; Met = meteorology; GAM = generalised additive model; RF = random forest; QRM = quantile regression model; NO 2 = nitrogen dioxide). Air quality is monitored before intervention, then the intervention is implemented, and finally air quality is monitored again, which is analysed and modelled employing different machine learning approaches. [Display omitted] In this paper, the impact of smart traffic interventions on air quality was assessed in Thatcham, West Berkshire, UK. The intervention linked NO 2 levels with the cycle time of the traffic lights. When NO 2 levels exceeded a certain threshold, the strategy was triggered, which reduced the traffic congestion by turning the traffic lights green. Eight Earthsense Zephyrs air quality sensors and nine inductive-loop traffic detectors were installed in Thatcham to simultaneously monitor the air quality and traffic flows, respectively. Compared to the pre-intervention period, the observed NO 2 concentrations decreased in June, July and August and increased in September 2021, however, this does not reveal the true effect of smart traffic intervention. Using the observed data on the days with- and without-exceedances, we developed two machine learning models to predict the Business-as-usual (BAU) air quality level, i.e., a generalised additive model for average concentration and a quantile regression model for peak concentration. Our results demonstrated that average predicted concentrations (BAU) were lower than the observed concentrations (with intervention) by 12.45 %. However, we found that peak concentrations decreased by 20.54 %. [ABSTRACT FROM AUTHOR]

Tugboat assistance is essential when large ships are berthing and unberthing, and requires ports to produce efficient tugboat schedules considering various constraints. Few studies optimize tugboat scheduling from multiple vectors simultaneously, however. This paper thus constructs a bi-objective, mixed-integer linear programming, green tugboat scheduling model in order to minimize the maximum completion time and total fuel consumption, which improves port service levels, decreases tugboat company operating expenditures and thus environmental pollution emissions. The proposed model also considers the time window characteristics of the tidal port. We use the non-dominated sorting genetic algorithm II (NSGA-II) framework integrating the characteristics of tugboat scheduling to solve the model. Finally, we make a case study about Guangzhou Port to validate the model and the algorithm via a comparison of results solved by NSGA-II and CPLEX solver. The Pareto fronts obtained show the trade-off relationship between the two objectives, and provide a basis for port tugboat scheduling plans. [ABSTRACT FROM AUTHOR]

• Mixed picture for socio-economic and demographic equity, in some cases equal but not equitable. • School Streets are less likely at schools in areas with worst air quality and high car dominance. • There are significant differences in provision between London's borough authorities. • Policies for hard-to-treat schools are needed to improve air quality inequities. School Streets are a street space reallocation scheme that has proliferated since the beginning of the Covid-19 pandemic in the UK, reducing motor traffic on streets outside many schools. Utilising a minimum-standards approach to equity, this paper examines the distribution of School Streets closures across social and environmental indicators of equity, and spatially across London's administrative geography. Using a multi-level regression analysis, we show that although School Streets have been equally distributed across several socio-demographic indicators, they are less likely to benefit schools in car-dominated areas of poor air quality, and their spatial distribution is highly unequal. This study presents an example of using environmental and spatial variables alongside more typical sociodemographic indicators in measuring the equity of school travel provision. For policymakers, the findings signal the need to implement complementary policies that can benefit schools with worse air quality, and to accelerate School Street implementation in slower districts. [ABSTRACT FROM AUTHOR]

This paper presents an integrated analysis of the costs and benefits of carefully constructed scenarios for the electrification of transport in Australia. Scenarios were constructed to responsively meet increased electricity demand, whilst maximising emission reduction, household finances and public health benefits. The scenarios bundle several technologies, including charging infrastructure, electric vehicles, home battery systems, and renewable energy. The fastest, mission-style, adoption scenario can reduce emissions by 9% of the 2030 carbon budget and reduce the loss of life by 24,000 by 2042. In all scenarios, government expenditure is dwarfed by the estimated public benefits, and households are nearly always better off in the medium to long term. Demonstrating the feasibility and advantages of surface transportation electrification in Australia, which presents cross-sections of rural and urban infrastructure, traffic and a large, socially and politically diverse population, provides broadly applicable evidence of the feasibility of electrification in other jurisdictions. [ABSTRACT FROM AUTHOR]