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1.
Electric vehicles (EVs) are predicted to increase in market share as auto manufacturers introduce more fuel efficient vehicles to meet stricter fuel economy mandates and fossil fuel costs remain unpredictable. Reflecting spatial autocorrelation while controlling for a variety of demographic and locational (e.g., built environment) attributes, the zone-level spatial count model in this paper offers valuable information for power providers and charging station location decisions. By anticipating over 745,000 personal-vehicle registrations across a sample of 1000 census block groups in the Philadelphia region, a trivariate Poisson-lognormal conditional autoregressive (CAR) model anticipates Prius hybrid EV, other EV, and conventional vehicle ownership levels. Initial results signal higher EV ownership rates in more central zones with higher household incomes, along with significant residual spatial autocorrelation, suggesting that spatially-correlated latent variables and/or peer (neighbor) effects on purchase decisions are present. Such data sets will become more comprehensive and informative as EV market shares rise. This work’s multivariate Poisson-lognormal CAR modeling approach offers a rigorous, behaviorally-defensible framework for spatial patterns in choice behavior.  相似文献   

2.
《Transport Policy》2006,13(4):329-338
This paper presents a methodology for the design of optimal transport strategies and demonstrates its application to six UK cities. An objective function representing the total welfare of a transport strategy is used to measure the performance of the strategy; the levels of policy instruments in a strategy, such as changes in public transport fares and frequency, are chosen such that the objective function is optimised. Two types of analysis are reported: sensitivity tests around individual policies to examine their relative impacts, and optimisations of packages of transport policies. The effects of spatial variations of the PT policies in the optimisations are also investigated.  相似文献   

3.
Over the past two decades, Germany has improved the quality of its public transport services and attracted more passengers while increasing productivity, reducing costs, and cutting subsidies. Public transport systems reduced their costs through organizational restructuring and outsourcing to newly founded subsidiaries; cutting employee benefits and freezing salaries; increasing work hours, using part-time employees, expanding job tasks, and encouraging retirement of older employees; cooperation with other agencies to share employees, vehicles, and facilities; cutting underutilized routes and services; and buying new vehicles with lower maintenance costs and greater passenger capacity per driver. Revenues were increased through fare hikes for single tickets while maintaining deep discounts for monthly, semester, and annual tickets; and raising passenger volumes by improved quality of service, and full regional coordination of timetables, fares, and services. Those efforts by public transport agencies were enhanced by the increasing costs and restrictions on car use in German cities. Although the financial performance of German public transport has greatly improved, there are concerns of inequitable burdens on labor, since many of the cost reduction measures involved reducing wages or benefits of workers.  相似文献   

4.
Similar to virtually all formerly socialist countries in Central and Eastern Europe, the Czech Republic has been experiencing a transport revolution since the shift from socialism to capitalism a decade ago. From 1988 to 1998, per-capita car ownership rose by 63% in the country as a whole, and by 93% in the capital city of Prague. Vehicle km of motor vehicle use have more than doubled. Conversely, public transport usage has fallen considerably, by 26% in the country as a whole, and by 19% in Prague. This modal shift from public transport to the private car has resulted from increased incomes, access to Western markets, declining real prices of cars and petrol, removal of restrictions on manufacturing and importing cars, and the car's attraction as a symbol of freedom, affluence, and status. The sharp reduction of subsidies for public transport has forced increases in fares and service cutbacks, which have also encouraged the shift toward the private car. Although the private car is very popular, the sudden surge in car ownership and use has caused significant social and environmental problems: roadway congestion, parking shortages, increased traffic accidents, air pollution, and noise. Given their severe financial limitations, Czech cities are struggling to preserve their public transport systems while accommodating the immensely popular private car.  相似文献   

5.
This article examines the consequences, for Paris, of the increase in two-wheel motor vehicle (2WMV) traffic (measured in vehicle/km). Our study reveals that, between 2000 and 2007, the subway's (Métro) share in total inner-Paris travel increased by 13.6%, the RER's share by 10.3% and the SNCF's share by 20.5%. These three means of transport account for 58% of daily travel. On the other hand, the bus share has decreased by 16% and that of cars by 23.7%. Private motor vehicles represent 37.3% of total travel. Looking at road traffic, where public transport (buses) and private motor transport compete for the use of limited road space, private motor vehicles account for 91.5% and public transport 8.5% of total travel.The 2WMV share in Paris traffic increased by 36% between 2000 and 2007, with 2WMVs now accounting for a share twice as large as that of buses. A survey has shown that 100 million additional passenger kilometres were made by 2WMV in 2007 compared to 2000. 53% of this increase comes from people shifting to 2WMV from public transport and 26.5% from private cars. The remaining 20% is attributable to the increased use of 2WMVs by those already owning such vehicles in 2000.Is the growth in the share of 2WMV traffic in Paris beneficial to the community? This shift in the means of transport generates time savings of €293 million and increases owners' vehicle usage costs by €49 million. The cost of accidents is increased by €49 million and the negative consequences in terms of pollution are estimated at €22.6 million. The welfare impact of the government revenue change is negative and equal to €4.7 million. In total, the gain for the community is therefore around €168 million. Accident costs are the key issue. The fact that there are on average 21 2WMV fatalities in Paris (average 2006–2007) for a means of transport accounting for 16% of passenger/km made every day in Paris offers a striking contrast to the 6 (average 2006–2007) fatalities concerning cyclists which account for a mere 0.1% of trips. The massive shift to 2WMV has taken place without any public policy support. Public policy could easily further improve the 2WMV cost-benefit balance by taking measures that would decrease the number of accidents.  相似文献   

6.
This work describes a methodology for determining the average vehicle kilometres travelled by the private national car fleet in Ireland and estimating the disaggregated CO2 and NOx emissions from private vehicles in the Irish road transport sector for the period 2000–2005 using national car test records. The developed methodology facilitates the calculation of greatly improved estimates for vehicle kilometres under a range of constraint variables and thereby enables the disaggregated analysis of specific vehicle fleet groups and their associated activity patterns to support evidence-based policy development. The results indicate that while older vehicles are contributing significantly to car NOx emissions; newer cars produce a higher share of CO2 emissions than older cars in the vehicle fleet.  相似文献   

7.
Informal paratransit operators using a range of vehicle types (including pickup trucks, small buses, and motorcycles) are a major provider of mobility in rural areas of the developing world. The paper describes a mixed method approach used to examine such operators’ decisions about vehicle deployment, route frequency, network organisation, and pricing in three rural districts in South Africa. New evidence is presented showing that the condition of rural roads (both paved and unpaved) affects the quantity and quality of public transport services provided, as well as the fares charged to passengers. This strengthens the case for judicious infrastructure investment as a way of improving rural access and livelihoods, and suggests how this might happen by way of leveraging better private sector responses. We also describe the emergence of a differentiated service hierarchy involving a variety of vehicle types suited to different operating conditions, and based on intentional coordination among operators of minibus and pickup truck (‘bakkie’) services. We argue that governments should promote such coordination and innovation in rural transport markets.  相似文献   

8.
Throughout the world, urban areas have been rapidly expanding, exacerbating the problem of many public transport (PT) operators providing service over different governmental jurisdictions. Over the past five decades, Germany, Austria, and Switzerland have successfully implemented regional PT associations (called Verkehrsverbund or VV), which integrate services, fares, and ticketing while coordinating public transport planning, marketing, and customer information throughout metropolitan areas, and in some cases, entire states. A key difference between VVs and other forms of regional PT coordination is the collaboration and mutual consultation of government jurisdictions and PT providers in all decision-making. This article examines the origins of VVs, their spread to 13 German, Austrian, and Swiss metropolitan areas from 1967 to 1990, and their subsequent spread to 58 additional metropolitan areas from 1991 to 2017, now serving 85% of Germany's and 100% of Austria's population. The VV model has spread quickly because it is adaptable to the different degrees and types of integration needed in different situations. Most of the article focuses on six case studies of the largest VVs: Hamburg (opened in 1967), Munich (1971), Rhine-Ruhr (1980), Vienna (1984), Zurich (1990), and Berlin-Brandenburg (1999). Since 1990, all six of those VVs have increased the quality and quantity of service, attracted more passengers, and reduced the percentage of costs covered by subsidies. By improving PT throughout metropolitan areas, VVs provide an attractive alternative to the private car, helping to explain why the car mode share of trips has fallen since 1990 in all of the case studies.  相似文献   

9.
This paper examines the distributional effects of alternative scenarios of urban public transport policies in the Paris Region using disaggregated data from the Global Transport Survey 2001–2002. We study two types of scenarios: fare adjustments, as in previous work, but also speed increase scenarios. We find that reducing public transport fares is progressive. Increasing the speed of public transport is also progressive whatever the mode. The most progressive option is to increase the speed of buses in the suburbs, while targeting the metro or the suburban rail are the least progressive alternatives. More generally, low-income individuals benefit more from fare reductions than from increases in public transport speed.  相似文献   

10.
《Transport Policy》2004,11(3):205-214
The article develops a cost model for ferry operators, which enables us to estimate how long-run marginal costs for transporting different categories of vehicles are related to trip lengths. The model is estimated using cross-sectional data from 64 ferry services in Norway. The present fare system for the ferries is then compared with marginal costs and with Ramsey fares with the presumption that the ferries' subsidy needs are at today's level. Ramsey pricing implicates steeper relationships between fares and trip lengths than present fares, in particular for heavy vehicles. Consequently, fares based on general principles of economic welfare should, under present financial constraints for the ferry operators, lead to lower fares for short journeys and significantly higher fares for long journeys.  相似文献   

11.
Peak oil is the term used to describe the point at which global oil production will peak and thereafter start to decline. Recognising that transport uses a significant portion of global energy, the shortage of fossil fuel in post peak oil era will pose a global challenge in the transport sector. The paper presents an assessment of international research to illustrate the possible time frame of peak oil. It investigates the key implications of the oil shortage that threaten to render the urban transport system of Australia ineffective. Synthesis of documented research evidence suggests three major implications in the urban transport sector: (1) a reduction of mobility for individuals, (2) an increase of transport disadvantage, and (3) a disruption of urban freight movement. In addition, the paper explores strategies to cope with the devastating effects of the shortage of the fossil fuel in the post peak oil era. A number of strategies to achieve sustainable mobility in the future urban transport system are presented. These strategies are summarised into three main themes: (1) a mode shift to alternate transport modes, (2) an integration of land use and transport planning, and (3) a global technical effort for alternate fuels and vehicles. It is expected that a concerted global effort in this regard can have a far-reaching effect in achieving sustainability in urban transport mobility.  相似文献   

12.
Emerging transportation technologies have the potential to significantly reshape the transportation systems and household vehicle ownership. Key among these transportation technologies are the autonomous vehicles, particularly when introduced in shared vehicle fleets. In this paper, we focus on the potential impact that fleets of shared autonomous vehicles might have on household vehicle ownership. To obtain initial insights into this issue, we asked a sample of university personnel and members of the American Automobile Association as to how likely they would consider relinquishing one of their household's personal vehicles if shared autonomous vehicles were available (thus reducing their household vehicle ownership level by one). For single-vehicle households, this would be relinquishing their only vehicle, and for multivehicle households (households owning two or more vehicles) this would be relinquishing just one of their vehicles. Possible responses to the question about relinquishing a household vehicle if shared autonomous vehicles are present are: extremely unlikely, unlikely, unsure, likely, and extremely likely. To determine the factors that influence this response, random parameters ordered probit models are estimated to account for the likelihood that considerable unobserved heterogeneity is likely to be present in the data. The findings show that a wide range of socioeconomic factors affects people's likelihood of vehicle relinquishment in the presence of shared autonomous vehicles. Key among these are gender effects, generational elements, commuting patterns, and respondents' vehicle crash history and experiences. While people's opinions of shared autonomous vehicles are evolving with the continual introduction of new autonomous vehicle technologies and shifting travel behavior, the results of this study provide important initial insights into the likely effects of shared autonomous vehicles on household vehicle ownership.  相似文献   

13.
This paper provides detailed accounts of the transport patterns at the Autonomous University of Barcelona (UAB), including its motivations, barriers and user preferences, and explores the main transport challenges faced by the UAB campus. This suburban university is an important transport activity generator in the Barcelona Metropolitan Region, which is committed to achieving sustainable transportation. Results have been obtained through a personal survey (n=5525) of members of the university community. These show that the main limitations for changing travel mode from private means to non-motorised or public modes of transport are: the lack of adequate infrastructure, the marginal role of walking and cycling as a means of transport, and the longer time involved using public transport.  相似文献   

14.
In this study, a framework is proposed for minimizing the societal cost of replacing gas-powered household passenger cars with battery electric ones (BEVs). The societal cost consists of operational costs of heterogeneous driving patterns' cars, government investments for charging deployment, and monetized environmental externalities. The optimization framework determines the timeframe needed for conventional vehicles to be replaced with BEVs. It also determines the BEVs driving range during the planning timeframe, as well as the density of public chargers deployed on a linear transportation network over time. We leverage data sets that represent US household driving patterns, as well as the automobile and the energy markets, to apply the model. Results indicate that it takes 8 years for 80% of our conventional vehicle sample to be replaced with electric vehicles, under the base case scenario. The socially optimal all-electric driving range is 204 miles, with chargers placed every 172 miles on a linear corridor. All public chargers should be deployed at the beginning of the planning horizon to achieve greater savings over the years. Sensitivity analysis reveals that the timeframe for the socially optimal conversion of 80% of the sample varies from 6 to 12 years. The optimal decision variables are sensitive to battery pack and vehicle body cost, gasoline cost, the discount rate, and conventional vehicles' fuel economy. Faster conventional vehicle replacement is achieved when the gasoline cost increases, electricity cost decreases, and battery packs become cheaper over the years.  相似文献   

15.
《Transport Policy》2005,12(3):185-198
Indian cities face a transport crisis characterized by levels of congestion, noise, pollution, traffic fatalities and injuries, and inequity far exceeding those in most European and North American cities. India's transport crisis has been exacerbated by the extremely rapid growth of India's largest cities in a context of low incomes, limited and outdated transport infrastructure, rampant suburban sprawl, sharply rising motor vehicle ownership and use, deteriorating bus services, a wide range of motorized and non-motorized transport modes sharing roadways, and inadequate as well as uncoordinated land use and transport planning. This article summarizes key trends in India's transport system and travel behavior, analyzes the extent and causes of the most severe problems, and recommends nine policy improvements that would help mitigate India's urban transport crisis.  相似文献   

16.
Focusing on adult members of German households, this paper investigates the determinants of public transit ridership with the aim of quantifying the effects of fuel prices, fares, person-level attributes, and characteristics of the transit system on transport counts over a five-day week. The reliance on individual data raises several conceptual and empirical issues, the most fundamental of which is the large proportion of zero values in transit counts. To accommodate this feature of the data, we employ modeling procedures referred to as zero-inflated models (ZIMs), which order observations into two latent regimes defined by whether the individual never uses public transport. Our estimates reveal fuel prices to have a positive and substantial influence on transit ridership, though there is no evidence for a statistically significant impact of the fare.  相似文献   

17.
This paper examines individuals motivations when purchasing vehicles, focusing upon what factors would encourage individuals to purchase hybrid electrical vehicle (HEV) or alternatively fuelled vehicle (AFV). AFVs in this paper refer to any cars run on alternatives to petrol and diesel. This research attempts to ascertain whether reductions in fuel costs, vehicle registration tax (VRT), or green house gas emissions would encourage individuals to purchase a HEV or an AFV instead of a conventional vehicle. VRT is an Irish tax that is levied on the purchase of new vehicles. One of the motivations to conduct this research was to examine a new car tax and VRT scheme introduced by the Irish government in 2008. This new policy rewards the purchase of environmentally friendly cars, with lower VRT and car tax rates. To understand individuals’ perceptions of these new taxes a survey was sent to recent customers of a car company in Ireland. The survey asked respondents about their recently purchased vehicle and how important they considered vehicle attributes such as environmental performance, fuel cost, and safety, before making their car purchase. The survey also contained a number of stated preference experiments that were designed to ascertain what factors influence individuals’ decisions when purchasing their new car. The results showed that respondents did not rate green house gas emissions or VRT as crucial attributes when purchasing a new vehicle. The vehicle attributes that respondents rated most highly were reliability, automobile safety, fuel costs, and the cost price. The majority of respondents agreed that HEVs and AFVs are better for the environment, cheaper to run than conventional vehicles and would be the vehicle of choice in ten years time.  相似文献   

18.
This paper examines the effect of pollution fees based on per mile emissions of reactive organic gases and oxides of nitrogen on tons of pollutants emitted, driving, fuel use and efficiency, new vehicle sales, and welfare in the South Coast region of California. The results suggest that VMT and gasoline demand would be reduced (although at a declining rate) while mpg would improve as households shifted to newer vehicles. Sales of new vehicles are projected to initially rise, then drop below base forecast levels as turnover of vehicles is reduced. Finally, the projected effects on household consumer surplus suggest that pollution fees may be regressive (although less so as households adjust their vehicle holdings), as a significant portion of older, higher polluting vehicles are owned by lower income households. The paper also compares pollution fees with voluntary accelerated vehicle retirement programs.  相似文献   

19.
One of the concerns that has aroused much scholarly attention in transport geography lately is the extent to which public transport provision enables the less privileged population segments, especially those without privately owned motorized vehicles, to participate in activities that are deemed normal within the society they live in. This study contributes to this line of inquiry by proposing a methodology for identifying public transit gaps, a mismatch between the socially driven demand for transit and the supply provided by transit agencies. The methodology draws on the latest accomplishments in the field of modeling time-continuous, schedule-based public transport accessibility. Accessibility levels to key destinations are calculated at regular time intervals, and synoptic metrics of these levels over various peak and off-peak time windows are computed for weekdays and weekends. As a result, a temporally reliable picture of accessibility by public transport is constructed. The obtained index of public transport provision is compared to a public transport needs index based on the spatial distribution of various socio-demographics, in order to highlight spatial mismatches between these two indices. The study area consists of Flanders, which is the northern, Dutch-speaking region of Belgium. The results indicate that mainly suburban areas are characterized by high public transport gaps. Due to the time-variability of public transport frequencies, these gaps differ over time.  相似文献   

20.
Alternative fuel vehicle technologies are needed to mitigate rising greenhouse gas emissions from transport. Social influence is integral to the diffusion of private vehicles which are highly visible and fulfil practical as well as social functions. This paper provides the first meta-analysis of empirical studies which measure the strength of social influence on consumer vehicle choice. A systematic literature review identified 21 studies that examined three types of social influence: interpersonal communication; neighbourhood effect; and conformity with social norms. A random effects meta-analysis found a significant and small to moderate effect of social influence on vehicle choices (r = 0.241, p < 0.001). The overall effect size did not vary significantly between types of social influence nor between types of vehicle (conventional or alternative fuel). However, further analysis using meta-regression found that heterogeneity in social influence effect size across studies was explained by differences in countries' cultural receptiveness to normative influence. These findings have important implications for policy and modelling analysis of alternative fuel vehicle adoption, for which diffusion is both a socially and culturally-mediated process.  相似文献   

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