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1.
Sci Total Environ ; 901: 166543, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37625707

RESUMO

The Madrid - Toledo high-speed rail (HSR) line is 74.5 km long, has an average speed of 140 km/h and a maximum speed of 270 km/h. It averages almost 104 million passenger-kilometres travelled and has a utilisation rate (passengers per available seats) of 0.75 as of 2019. This study analyses the life cycle greenhouse gases (GHG) emissions of the Madrid - Toledo HSR line using the life cycle assessment methodology, taking into consideration the stages of construction, maintenance and operation for the infrastructure, as well as the manufacturing, maintenance and operation stages for trains. The most significant stage is infrastructure construction, which accounts for an average 75 % emissions, followed by train operation, with an average 18.2 %. The results highlight several environmental benefits of the deployment of the line, as after 40 years of operation there will be an average 21 % reduction in GHG emissions for passenger mobility between Madrid and Toledo compared to the case where no HSR line was built. Moreover, the line's GHG emissions are offset between 19 and 23 years after starting operation, mainly due to the emissions avoided by passengers switching to a carbon-friendlier mode of transportation in terms of operation, and the adoption of a 100 % renewable energy mix for the operation of trains since 2019. These findings point to opportunities for improving the life cycle GHG emissions of high-speed rail lines, such as increasing the occupancy of trains by applying new pricing policies and investing in intermodal infrastructures to achieve higher modal shift rates, promoting proximity criteria for the supply of raw materials during the infrastructure construction stage and improving the maintenance stage to prolong the lifetime of the infrastructure, thus deferring life cycle emissions for longer.

2.
Urban Rail Transit ; 9(1): 31-41, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910688

RESUMO

This study aims to analyse the inter-rail modal shift behaviour of suburban rail passengers to examine ridership for the proposed metro extension corridor in Chennai, India. This investigation was conducted in 2019 as part of a feasibility study for the extension of the metro line spanning between Chennai Airport and Kilambakkam, a southern suburb of Chennai. The same origin-destination pair is also served by the suburban rail system. It is an extension of the operating line from Washermenpet to the airport of the Phase I metro project. For this inter-rail competition study, a sample of 272 suburban rail passengers covering work, education and other trip purposes were interviewed using a stated preference questionnaire. Six stated scenarios were considered for analyses which included travel time saving by using the metro along with the fare difference between metro and bus. The study revealed that suburban rail passengers were less concerned about travel time saving and gave priority to fare difference irrespective of trip purpose. This shows the unique metro choice behaviour of suburban rail travellers in the Indian context.

3.
Transp Res Part A Policy Pract ; 164: 186-205, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35974744

RESUMO

During the year 2020, the COVID-19 pandemic affected mobility around the world, significantly reducing the number of trips by public transport. In this paper, we study its impact in five South American capitals (i.e., Bogotá, Buenos Aires, Lima, Quito and Santiago). A decline in public transport patronage could be very bad news for these cities in the long term, particularly if users change to less sustainable modes, such as cars or motorbikes. Notwithstanding, it could be even beneficial if users selected more sustainable modes, such as active transport (e.g., bicycles and walking). To better understand this phenomenon in the short term, we conducted surveys in these five cities looking for the main explanation for changes from public transport to active and private modes in terms of user perceptions, activity patterns and sociodemographic information. To forecast people's mode shifts in each city, we integrated both objective and subjective information collected in this study using a SEM-MIMIC model. We found five latent variables (i.e., COVID-19 impact, Entities response, Health risk, Life related activities comfort and Subjective well-being), two COVID-19 related attributes (i.e., new cases and deaths), two trip attributes (i.e., cost savings and time), and six socio-demographic attributes (i.e., age, civil status, household characteristics, income level, occupation and gender) influencing the shift from public transport to other modes. Furthermore, both the number of cases and the number of deaths caused by COVID-19 increased the probability of moving from public transport to other modes but, in general, we found a smaller probability of moving to active modes than to private modes. The paper proposes a novel way for understanding geographical and contextual similarities in the pandemic scenario for these metropolises from a transportation perspective.

4.
BMC Public Health ; 22(1): 1512, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945528

RESUMO

BACKGROUND: A high proportion of adolescents worldwide are not doing enough physical activity for health benefits. Replacing short motorised trips with walking or cycling has the potential to increase physical activity at the population level. This study aimed to estimate the proportion of short distance motorised trips that could be replaced with walking or cycling, and the potential physical activity gains by sociodemographic and trip characteristics. METHODS: Data were from a subsample of the NEighbourhood Activity in Youth (NEArbY) study conducted among adolescents in Melbourne. A total of 217 adolescents with at least one motorised trip completed a survey and wore a Global Positioning Systems (GPS) device for eight consecutive days. Classification of travel modes were based on speed. GPS data points were geocoded in ArcGIS. Motorised trips within walkable (1.3 km) and cyclable (4.2 km) distances were identified (threshold based on 80th percentile of walking and cycling trip distances among Victorian adolescents), and the additional physical activity minutes that could be accrued by replacing walkable or cyclable motorised trip to active trips were quantified. Multilevel linear regression was used to assess differences in physical activity minutes gain by sociodemographic and trip characteristics. RESULTS: A total of 4,116 motorised trips were made. Of these, 17% were walkable and 61% were cyclable. Replacing motorised trips by walking and cycling resulted in estimated gains of six minutes and 15 min of physical activity per day, respectively. CONCLUSION: The sizable proportion of replaceable trips and potential physical activity gains from this shift calls for attention to improve safe and connected infrastructure to support active travel.


Assuntos
Sistemas de Informação Geográfica , Meios de Transporte , Adolescente , Ciclismo , Exercício Físico , Humanos , Viagem , Caminhada
5.
Transp Res Part A Policy Pract ; 159: 17-34, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35308089

RESUMO

COVID-19 has dramatically impacted urban mobility, of which public transport (PT) has been particularly affected. With PT ridership plummeting due to infection fears and many people returning to work, there is a danger of a steep rise in car use that would exacerbate environmental and health problems. Therefore, other modes such as bike sharing should be considered as potential alternatives during the coronavirus pandemic. This study focuses on assessing how coronavirus has impacted bike sharing by implementing a travel behaviour survey to the users of GIRA, the bike sharing system (BSS) of Lisbon. While the coronavirus has led some to decrease the frequency of use or quit the system, other users have increased the usage or joined GIRA during the pandemic. Furthermore, most users who have quit or decreased the usage of GIRA justify their decision not so much on avoiding the risk of infection (although for some it is an important reason) but on having stopped commuting due to COVID-19. The survey has also revealed substantial changes not only on the usage patterns of GIRA users but also on their relationship with other modes of transport. While before the pandemic, most respondents were shifting from PT to GIRA, that percentage has declined, with an increase on the share of users replacing walking, private car, and personal cycling. Moreover, the motivations for using bike sharing related with avoiding PT and maintaining a social distance during the trip have gained more relevance. Concurrently, the perceived safety of using PT has drastically declined, and while the perceived safety of using GIRA has also decreased it was in a much smaller scale. Policy insights can be derived from this research on how bike sharing can contribute to a more sustainable and resilient urban transport system. During infectious public health crises such as COVID-19, BSS can be a viable transport alternative, not only providing the population with an affordable mode of transport where social distancing can be maintained in most of the trip but also mitigating a modal shift from PT to the private car.

6.
Transp Res Interdiscip Perspect ; 13: 100548, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35098106

RESUMO

COVID-19 pandemic has caused adverse impacts on different aspects of life around the globe, including travelers' mode choice behavior. To make their travel safe, transportation planners and policymakers need to understand people's perceptions of the risk of COVID-19 transmission in different travel modes. This study aimed to estimate mode-wise perceived risk of viral transmission and identify the factors that influenced the perceived risk in Bangladesh. The study used a five-point Likert scale to measure the perceived risk of COVID-19 transmission in each travel mode. Using ordinal logistic regression models, the study explored the factors that influenced the perceived risk of COVID-19 transmission in different travel modes. The study found that people perceived a very high risk of viral transmission in public transport (bus), moderate risk in shared modes (rickshaw, auto-rickshaw, ridesharing), and very low risk in private modes (private car, motorcycle/scooter, walking, cycling). Such high-risk perception of viral transmission in public transport and shared modes might lead to a modal shift to private modes, which would worsen urban transport problems and undermine sustainable transportation goals. The study also found that socio-economic factors (gender, age, income) significantly influenced perceived risks in all travel modes. Contrarily, psychological factors (worry, care, and trust) were significant only for public and shared modes, but not for private modes. Lastly, travel behavior-related factors influenced perceived risk in shared and private modes.

7.
Environ Int ; 159: 107030, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34890901

RESUMO

CONTEXT: Policies aiming at decreasing air pollutants (e.g., fine particulate matter, PM2.5) are often designed without targeting an explicit health benefit nor carrying out cost-benefit analyses. METHODS: We developed a transdisciplinary backward and forward approach at the conurbation level: from health objectives set by local decision-makers, we estimated which reductions in PM2.5 exposures and emissions would allow to reach them, and identified urban policies leading to these reductions (backward approach). We finally conducted health impact and cost-benefit analyses of these policies (forward approach). The policies were related to the most emitting sectors in the considered area (Grenoble, France), wood heating and transport sectors. The forward approach also considered the health impact and co-benefits of these policies related to changes in physical activity and CO2 emissions. FINDINGS: Decision-makers set three health targets, corresponding to decreases by 33% to 67% in PM2.5-attributable mortality in 2030, compared to 2016. A decrease by 42% in PM2.5 exposure (from 13.9 µg/m3) was required to reach the decrease by 67% in PM2.5-attributable mortality. For each Euro invested, the total benefit was about 30€ for policies focusing on wood heating, and 1 to 68€ for traffic policies. Acting on a single sector was not enough to attain a 67% decrease in PM2.5-attributable mortality. This target could be achieved by replacing all inefficient wood heating equipment by low-emission pellet stoves and reducing by 36% the traffic of private motorized vehicles. This would require to increase the share of active modes (walking, biking…), inducing increases in physical activity and additional health benefits beyond the initial target. Annual net benefits were between €484 and €629 per capita for policies with report on active modes, compared to between €162 and €270 without. CONCLUSIONS: Urban policies strongly reducing air pollution-attributable mortality can be identified by our approach. Such policies can be cost-efficient.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Análise Custo-Benefício , Avaliação do Impacto na Saúde , Calefação/efeitos adversos , Material Particulado/análise , Material Particulado/toxicidade , Políticas
8.
Sci Total Environ ; 791: 148158, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412397

RESUMO

The escalating concerns regarding air pollution problems surrounding port cities have attracted much research attention. The Port of Shenzhen is one of the busiest container ports worldwide, only third to Shanghai and Singapore globally. However, 70% of the freight transportation demand is satisfied via on-road trucks, leading to serious traffic congestion, road accidents and air pollution issues in the city of Shenzhen. This study aims to assess the environmental benefits of modal shift of port-connecting freight transportation by increasing the use of rail and waterborne systems in Shenzhen. To evaluate the environmental benefits of the multimodal transportation strategy in 2025, we employed traffic datasets with a high spatial resolution and a transportation demand model to establish emission inventories and applied them in air quality simulations. Our results indicate that the implementation of multimodal transportation systems could notably reduce the truck volume along major freight corridors, except for roads adjacent to the planned inland ports. The freight traffic activities along the major freight corridors are reduced by nearly 70% over the original freight volume, resulting in a drastic reduction in the emission intensity. Under the most progressive policy-enhanced strategy (PPP) scenario, the total well-to-wheel (WTW) NOX, fine particulate matter (PM2.5) and CO2 emissions could be reduced by 8881 t, 104.8 t and 688 × 103 t, respectively. The NO2 concentration in traffic-intensive areas could be reduced by 5 µg/m3, and the 8-h maximum O3 concentration could be reduced by 0.34 µg/m3 on the average (up to 1.1 µg/m3 in certain areas). Our research indicates that a shift from traditional road transport to cleaner railway and waterway transport could deliver transportation and environmental benefits to port cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Melhoria de Qualidade , Água
9.
Environ Sci Pollut Res Int ; 28(48): 68188-68211, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34268690

RESUMO

The driving pattern of three-wheeled auto-rickshaws is governed by commuter's demands on certain fixed roads that offer flexible mobility solutions in a mid-size city. This flexibility creates unique driving patterns, frequent stop-and-go conditions, frequent acceleration, braking, and excessive idling, which affect emission rates. Existing emission testing regulation based on the driving cycle does not represent real-world conditions. In this paper, the real-world driving cycle of three-wheeled auto-rickshaw has been developed to provide realistic CO, HC, and NOX pollutants and see the effect of introducing modal shift of electric auto-rickshaw to reduce emission for India. Two policy scenarios were evaluated (1) with a 5% modal shift to electric auto-rickshaw, and (2) without modal shift. The results indicate that with a 5% shift to electric auto-rickshaw, by 2030, emissions will decrease by 6.30% compared to the baseline scenario. Further, by 2030, the projected CO emission would be 1,696,670 ton/year, and HC and NOX emissions would be 2,067,371 ton/year. Results can be useful for policy interventions towards cleaner fuel and the aggressive adoption for reducing pollution from auto-rickshaw.


Assuntos
Poluentes Atmosféricos , Condução de Veículo , Poluentes Atmosféricos/análise , Cidades , Eletricidade , Poluição Ambiental , Índia , Emissões de Veículos/análise
10.
Transp Policy (Oxf) ; 111: 82-89, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36568350

RESUMO

Developing countries are more fragile in the face of the crippling Covid-19 pandemic. Transportation is one of the major industries that has been hardly hit worldwide, and it is more worrying for these countries that already have challenges such as high modal share of private cars, air pollution, and high fatalities due to car accidents. This paper is one of its first kinds that studies the impact of this pandemic on the transportation of Tehran, the capital of Iran, which is one of the forefronts of the battle. In the first step and to get better insights from the travel behavior of passengers due to the pandemic, an online questionnaire is developed and distributed. Priorities for mode choice before and during the pandemic decrease and increase in the share of different modes and the impact of having a high-risk person in the family is studied. Subway had the most decrease and private cars had the highest increase. Hence, two logit models are developed to explain the variables that affect shifting away from the subway and shifting to private cars. Based on the results, a follow-up survey some months later and ridership trends of public transportation during the pandemic, four scenarios are envisaged for the post-corona world, the most probable one is highlighted and policies are recommended to better manage the situation.

11.
Chemosphere ; 249: 126140, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32065995

RESUMO

Presented here are size-resolved aerosol measurements conducted using cascade impactor set at breathing zone in indoor-outdoor residential microenvironments. PM2.5 contributed about 64-80% of PM10 in which over 29% of mass was shared by PM0.25. Total PM concentration varied from 261 ± 22 µg/m3 (indoors) to 256 ± 64 µg/m3 (outdoors) annually; whilst summer and monsoon demonstrated 1.2- and 1.9- times lower concentration than winters. The measured metals ranged between 9% (in PM2.5-10) to 18% (in PM1-2.5) of aerosol concentration; whereby crustal elements dominated coarse fractions with relatively higher proportion of toxic elements (Ba, Cd, Co, Cr, Cu, Ni) in ultrafine range. Considering lognormal particle size distribution (PSD), accumulation mode represented the main surface area during entire monitoring period (Mass Median Aerodynamic Diameter (MMAD) < 1). PSD of metal species reflected their different emission sources with respect to season integrated samples. High air exchange conditions permitted the shift of indoor PSD pattern closer to that of outdoor air while low ventilation in winters reflected modal shift of metals (Pb, Mg. K) towards larger size particles. Relative surge towards smaller diameter size of soluble metal fraction relative to the total concentration of toxic elements was noted on an annual basis with high infiltration capacity of smaller size particulates (Finf =1.36 for ultrafine particles in summers) identified through indoor-outdoor regression analysis. Principal Component Analysis identified sources such as vehicular traffic, combustion, crustal emission with activities viz. smoking and those involving use of electric appliances.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Índia , Metais/análise , Tamanho da Partícula , Análise de Regressão
12.
Transp Res Interdiscip Perspect ; 8: 100255, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34173481

RESUMO

Various measures were recommended or imposed by the governments to control the spread of COVID-19. Travel behaviors are significantly influenced due to such measures. However, people have various travel needs ranging from grocery shopping to work. This study examines the changes that occurred in travel behavior due to the COVID-19 pandemic. Data were collected through an online questionnaire survey that included questions on trip purpose, mode choice, distance traveled, and frequency of trips before and during COVID-19. 1203 responses were collected from various countries around the world. Results explained that trip purpose, mode choice, distance traveled, and frequency of trips for the primary travel were significantly different before and during the pandemic. Further, the majority of trips were made for shopping during the pandemic. There was a significant shift from public transport to private transport and non-motorized modes. People placed a higher priority on the pandemic related concerns while choosing a mode during the pandemic as compared to the general concerns. Gender, car ownership, employment status, travel distance, the primary purpose of traveling, and pandemic-related underlying factors during COVID-19 were found to be significant predictors of mode choice during the pandemic. Outcomes of this study could be useful in transport planning and policymaking during pandemics based on the travel needs of people. In particular, government authorities could utilize such knowledge for planning smart and partial lockdowns. Service providers, e.g., taxi companies and retailers, could use such information to better plan their services and operations.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31540094

RESUMO

The emergence of dockless bike sharing in recent years has reduced the usage of private cars, especially usage for short-distance trips (within 2 km). In this paper, a modified technology acceptance model (TAM) is proposed to investigate from the psychological perspective drivers' willingness to shift to dockless bike sharing. The modified TAM includes the perceived usefulness of dockless bike sharing, perceived ease-of-use of dockless bike sharing, perceived health of dockless bike sharing, attitudes toward dockless bike sharing, and willingness to shift to dockless bike sharing. Data are obtained through offline communications with car drivers. The results show that two-thirds of car drivers are willing to use dockless bike sharing in short-distance trips. Perceived health, perceived ease-of-use, and perceived usefulness have significant positive effects on people's attitudes toward dockless bike sharing. As expected, people's attitudes toward dockless bike sharing are positively correlated with their willingness to shift. Policy implications are discussed to prompt the modal shift from private cars to dockless bike sharing according to the results.


Assuntos
Automóveis , Ciclismo/psicologia , Adulto , Atitude , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
15.
Transp Res Part A Policy Pract ; 95: 320-333, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28163399

RESUMO

Heavy dependency on car use leads to traffic congestion, pollution, and physical inactivity, which impose high direct and indirect costs on society. Promoting walking and cycling has been recognised as one of the means of mitigating such negative effects. Various approaches have been taken to enhance walking and cycling levels and to reduce the use of automobiles. This paper examines the effectiveness of infrastructure interventions in promoting walking and cycling for transport. Two related sets of panel data, covering elapsed time periods of one and two years, were analysed to track changes in travel behaviour following provision of new walking and cycling infrastructure so that modal shift from private car use to walking and cycling can be investigated. Two types of exposure measures were tested: distance from the infrastructure (a measure of potential usage), and actual usage of the infrastructure. Only the latter measure was statistically significantly associated with modal shift. This in turn suggested that infrastructure provision was not a sufficient condition for modal shift, but may have been a necessary condition. Along with the use of new infrastructure, the loss of employment, higher education, being male and being part of the ethnic majority were consistently found to be significantly and positively associated with modal shift towards walking and cycling. The findings of this study support the construction of walking and cycling routes, but also suggest that such infrastructure alone may not be enough to promote active travel.

16.
Ciênc. Saúde Colet. (Impr.) ; 16(12): 4731-4744, dez. 2011. tab
Artigo em Inglês | LILACS | ID: lil-606599

RESUMO

Although from a societal point of view a modal shift from car to bicycle may have beneficial health effects due to decreased air pollution emissions and increased levels of physical activity, shifts in individual adverse health effects such as higher exposure to air pollution and risk of a traffic accident may prevail. We have summarized the literature for air pollution, traffic accidents, and physical activity using systematic reviews supplemented with recent key studies. We quantified the impact on all-cause mortality when 500,000 people would make a transition from car to bicycle for short trips on a daily basis in the Netherlands. We estimate that beneficial effects of increased physical activity are substantially larger (3-14 months gained) than the potential mortality effect of increased inhaled air pollution doses (0.8-40 days lost) and the increase in traffic accidents (5-9 days lost). Societal benefits are even larger because of a modest reduction in air pollution and traffic accidents. On average, the estimated health benefits of cycling were substantially larger than the risks relative to car driving for individuals shifting their mode of transport.


Embora uma mudança do uso de carro para bicicleta possa trazer efeitos benéficos para a saúde devido à diminuição da poluição do ar e a um aumento da atividade física, esta mudança também pode trazer efeitos adversos à saúde como exposição à poluição e risco de acidentes de trânsito, os quais podem superar os benefícios. Nós resumimos a literatura sobre poluição do ar, acidentes de trânsito e atividade física, utilizando revisões sistemáticas suplementadas com estudos recentes. Quantificamos também o impacto na causa de mortalidade se 500 mil pessoas fizessem a transição de carro para bicicleta em viagens curtas diárias na Holanda. Estimamos que os efeitos benéficos do aumento da atividade física são substancialmente maiores do que o efeito potencial da mortalidade por inalação de ar poluído e aumento de acidentes de trânsito. Os benefícios sociais são ainda maiores devido a uma modesta redução na poluição do ar e nos acidentes de trânsito. Em média, os benefícios de saúde devido ao uso da bicicleta são substancialmente maiores do que os riscos relativos a dirigir um carro para pessoas em transição do modo de transporte.


Assuntos
Humanos , Ciclismo , Promoção da Saúde , Acidentes de Trânsito/estatística & dados numéricos , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Atividade Motora , Fatores de Risco
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