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1.
With a growing urban population, it is crucial to maintain and develop environmentally friendly transport modes. However, while one of the most important indicators of environmental performance is water use, very few studies have quantified the total water requirements associated with different transport modes.This study uses input-output analysis to quantify the total water requirements of different passenger-transport modes in Melbourne, Australia, including the direct and indirect water requirements of petrol cars, regional diesel trains and electric metropolitan trains.Results show that urban electric trains are the least water intensive transport mode (3.4 L/pkm) followed by regional diesel trains (5.2 L/pkm) and petrol cars (6.4 L/pkm). These intensities result in average daily per capita transport-related water use that can be greater than residential water use. Findings also show that occupancy rates greatly affect the water intensity of transport modes and that when occupied by five passengers, cars are the least water intensive transport mode. Finally, this study shows that water use associated with transport depends on a range of factors across the supply chain and that indirect requirements associated with operations, including administration, advertisement, servicing and others, can represent a significant share of the total. Reducing the total water requirements of transport modes is therefore a shared responsibility between all the actors involved and integrated action plans are needed in order to reduce water use associated with transport.  相似文献   

2.

Transport related social exclusion is one aspect of people with disabilities’ marginal position in economic, social and civic life. This study aims at presenting main tendencies in empirical research on transport and disability, and therein defining functional requirements that transport solutions must comply with in order to facilitate social inclusion. Based on review of thirty-four empirical studies, this study presents eight functional requirements for inclusive transport. Aspects of each requirement are described and links to social exclusion are explored. Further, the strengths and limits of the review as well as relevance for practice is discussed. Although the study is limited to research in English and Scandinavian languages, the authors believe that the transferability of the results beyond the geographical scope of this study is not challenged by the requirements themselves, but rather to what degree and in what ways these requirements are championed and pursued. The functional requirements are defined without reference to particular travel purposes or mode of transport and represent a systematic approach for making discretional assessment of transport solutions.

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3.
Abstract

A stated preference (SP) experiment of car ownership was conducted in Mumbai Metropolitan Region (MMR) of Maharashtra in India. A full factorial experiment was designed to considering various attributes such as travel time, travel cost, projected household income, car loan payment and servicing cost. Data on 357 individuals were collected which resulted in 3213 observations for the calibration of the work trip and recreational trip car ownership models. The car ownership alternatives considered 0, 1 and 2 cars. A multinomial logit framework was used to develop the car ownership model taking the household as a decision unit. The specification and results of the SP car ownership model are discussed. The observed and predicted values matched reasonably when the validity of the SP car ownership model was tested against revealed preference (RP) data. The car ownership models developed in this study exhibit a satisfactory goodness of fit. It is concluded that the SP modelling approach can be successfully used for modelling car ownership decisions of households in developing countries.  相似文献   

4.
Transport is Australia’s third largest and second fastest growing source of greenhouse gas (GHG) emissions. The road transport sector makes up 88% of total transport emissions and the projected emissions increase from 1990 to 2020 is 64%. Achieving prospective emission reduction targets will pose major challenges for the road transport sector. This paper investigates two targets for reducing Australian road transport greenhouse gas emissions, and what they might mean for the sector: emissions in 2020 being 20% below 2000 levels; and emissions in 2050 being 80% below 2000 levels. Six ways in which emissions might be reduced to achieve these targets are considered. The analysis suggests that major behavioural and technological changes will be required to deliver significant emission reductions, with very substantial reductions in vehicle emission intensity being absolutely vital to making major inroads in road transport GHG emissions.  相似文献   

5.
This paper applies a life cycle methodology to estimate activity-related contributions of transport modes to GHG emissions. The methodology uses national input–output tables, environmental accounts, household budget data and nutritional data to derive food-sector GHG coefficients of consumption for ten European countries. The food energy requirements for each mode of transport are estimated taking account of the modal activity level and energy requirements. Typical national food energy-related emissions for walking, cycling, and driving ranged from 25.6 to 77.3 gCO2-eq/pass.km, 10.4–31.4 gCO2-eq/pass.km and 1.7–5.2 gCO2-eq/pass.km; passenger transport was found to result in no food-related emissions above those for a resting individual. Emissions vary between countries depending on the emissions intensities of their energy sectors as well as food prices and average body weights. A life cycle assessment of modal emissions in the UK is undertaken using the food-energy emissions intensities estimated and car travel was found to have the highest emissions intensity, followed by bus, cycling and walking.  相似文献   

6.
The major aim of this work is to develop a primary tool for the quantitative determination of land areas needed to fulfil the diverse functions of public transport. The need for such a tool is obvious; worldwide there is a lack of criteria for determining the types of areas needed, their size, and relative location in the urban system. Moreover, there is a lack of awareness regarding land allocation during the various planning stages, both by urban planners and decision makers. This work attempts to identify various types of facilities to be allocated within the urban framework, and to determine quantitative guidelines for the land needed for them. A statistical analysis is performed in order (i) to identify major transit facilities and operational data functions for which land must be allocated, and (ii) to forecast areas for types of facilities not dealt with by the statistical analysis. The statistical forecast is based on fitting a regression model to the input data. The outcome of this work is presented in terms of three statistical relationships and an indirect relationship: between socio-economic and demographic variables (independent) to the dependent variables, either operating variables or land area variables, and between operating variables (independent) and land area variables (dependent), where for the latter there is also an indirect relationship while using standards.  相似文献   

7.
This paper investigates the well-to-wake energy consumption and greenhouse gas emissions of several key SOX abatement options in marine transportation, ranging from the manufacture of low sulfur fuels to equipping the vessel with suitable scrubber solutions. The findings suggest that a scrubber system, used with current heavy fuel oils, has the potential to reduce SOX emissions with lower well-to-wake energy consumption and greenhouse gas emissions than switching to production of low sulfur fuels at the refinery. A sensitivity analysis covering a series of system parameters shows that variations in the well-to-tank greenhouse gas emissions intensity and the energy efficiency of the main engine have the highest impacts in terms of well-to-wake emissions.  相似文献   

8.
This work examines the temporal–spatial variations of daily automobile distance traveled and greenhouse gas emissions (GHGs) and their association with built environment attributes and household socio-demographics. A GHGs household inventory is determined using link-level average speeds for a large and representative sample of households in three origin–destination surveys (1998, 2003 and 2008) in Montreal, Canada. For the emission inventories, different sources of data are combined including link-level average speeds in the network, vehicle occupancy levels and fuel consumption characteristics of the vehicle fleet. Urban form indicators over time such as population density, land use mix and transit accessibility are generated for each household in each of the three waves. A latent class (LC) regression modeling framework is then implemented to investigate the association of built environment and socio-demographics with GHGs and automobile distance traveled. Among other results, it is found that population density, transit accessibility and land-use mix have small but statistically significant negative impact on GHGs and car usage. Despite that this is in accordance with past studies, the estimated elasticities are greater than those reported in the literature for North American cities. Moreover, different household subpopulations are identified in which the effect of built environment varies significantly. Also, a reduction of the average GHGs at the household level is observed over time. According to our estimates, households produced 15% and 10% more GHGs in 1998 and 2003 respectively, compared to 2008. This reduction can be associated to the improvement of the fuel economy of vehicle fleet and the decrease of motor-vehicle usage – e.g., a decrease of 4% is observed for fuel efficiency rates and 12% for distance according to the raw average estimates from 1998 with respect to 2008. A strong link is also observed between socio-demographics and the two travel outcomes. While number of workers is positively associated with car distance and GHGs, low and medium income households pollute less than high-income households.  相似文献   

9.
This paper estimates the total embodied energy and emissions modal freight requirements across the supply chain for each of over 400 sectors using Bureau of Transportation Statistics Commodity Flow Survey data and Bureau of Economic Analysis economic input-output tables for 2002. Across all sectors, direct domestic truck and rail transportation are similar in magnitude for embodied freight transportation of goods and services in terms of ton-km. However, the sectors differ significantly in energy consumption, greenhouse gas emissions, and costs per ton-km. Recent pressure to reduce energy consumption and emissions has motivated a search for more efficient freight mode choices. One solution would be to shift freight transportation away from modes that require more energy and emit more (e.g., truck) to modes that consume and emit less (e.g., rail and water).Our results show there are no individual sectors for which targeting changes would significantly decrease the total freight transportation energy and emissions, therefore we have also looked at the prospect of policies encouraging many sectors to shift modes. There are four scenarios analyzed: (1) shifting all truck to rail, shifting top 20% sector mode choice, (2) based on their emissions, (3) based on a multi-attribute analysis, and (4) increasing truck efficiency (e.g., mpg). Increasing truck efficiency by 10% results in similar energy and emissions reductions (approximately 7% for energy and 6% for emissions) as targeting the top 20% of sectors when selected based on emissions, whereas selecting the top 20% based on availability to shift from truck results in slightly less reductions of energy and emissions. Implementing policies to encourage higher efficiency in freight trucks may be a sufficient short term goal while efforts to reduce truck freight transportation through sectoral policies are implemented in the long term.  相似文献   

10.
This study provides a comprehensive comparison of well-to-wheel (WTW) energy demand, WTW GHG emissions, and costs for conventional ICE and alternative passenger car powertrains, including full electric, hybrid, and fuel cell powertrains. Vehicle production, operation, maintenance, and disposal are considered, along with a range of hydrogen production processes, electricity mixes, ICE fuels, and battery types. Results are determined based on a reference vehicle, powertrain efficiencies, life cycle inventory data, and cost estimations. Powertrain performance is measured against a gasoline ICE vehicle. Energy carrier and battery production are found to be the largest contributors to WTW energy demand, GHG emissions, and costs; however, electric powertrain performance is highly sensitive to battery specific energy. ICE and full hybrid vehicles using alternative fuels to gasoline, and fuel cell vehicles using natural gas hydrogen production pathways, are the only powertrains which demonstrate reductions in all three evaluation categories simultaneously (i.e., WTW energy demand, emissions, and costs). Overall, however, WTW emission reductions depend more on the energy carrier production pathway than on the powertrain; hence, alternative energy carriers to gasoline for an ICE-based fleet (including hybrids) should be emphasized from a policy perspective in the short-term. This will ease the transition towards a low-emission fleet in Switzerland.  相似文献   

11.
Introducing sustainable ways to use energy and transport resources is of paramount importance for creating pathways to more liveable futures. Islands not interconnected to the main grid offer, because of their typically small size, short point-to-point travel distances that suit better than most landscapes the range limitations of today’s electromobile eco-systems. This makes them a unique test-bed that may assist researchers, businesses and policy-makers in developing a better understanding of the diverse opportunities and challenges that come with supporting electric-drive vehicle (EV) infrastructure investments that actively prioritise renewable energy sources (RES). This paper reports the findings of a Q method study that looks into the attitudes of 44 key stakeholders that have a thorough theoretical and empirical knowledge of the existing power and mobility portfolios in such islandic landscapes. Our analysis identifies and presents three distinct groups of stakeholders with different priorities and visions: the ‘Tech Enthusiasts’, the ‘Transform Transport First Supporters’ and the ‘Fiscal Focus Executives’. All our respondents agree on the need for radically transforming the current transport-energy nexus offering. They identify the importance of integrated and clean solutions and recognise that support of pilot applications is more critical than research and development (R&D). They also expect technological breakthroughs to increase market maturities and reduce renewable energy production costs and feel that end-users are still hesitant to buy EVs and need incentives to do so.  相似文献   

12.

In recent years, the world economy has become more integrated internationally and container transportation has become increasingly more important as the proportion of all trade using containers is continuously growing. In order to adapt to the increasing containerization trend, it is essential to plan and construct adequate ports and facilities to cope with this development.

Based on the analysis of factors influencing container movements, this paper illustrates the logical relationships for a distribution model, which has been used to predict the distribution of containers among the three main Seaports near Shenzhen and Hong Kong. A fuzzy number‐based distribution model is outlined in the paper. The paper illustrates the main influencing factors and their logical relationships and proposes a primary distribution model where the attractiveness of each port has been calibrated. The results show that the Port of Hong Kong is significantly more attractive than the other two ports modelled and is likely to continue to be so in the future.  相似文献   

13.
This paper analyses the choice between road and rail in Spain where rail market share for freight is still residual. Discrete choice models are estimated with data obtained through a two-phase fieldwork, thus allowing us to carry out a stated preference efficient design for each interviewee. We analyse the existence of attribute cut-offs and the presence of a segment of the population with a zero value of frequency. Our results show that ignoring the existence of cut-offs and segments of the population with polarised valuations can lead to erroneous conclusions in terms of the possibilities of rail for absorbing significant quota.  相似文献   

14.
The usual formulation of total factor productivity (TFP) growth is generalised to a multi-output, multi-input production process. The general expression derived makes no assumption about the objective of the firm, nor about the relationship between prices and associated marginal values. It can therefore accommodate, in addition to various firm objectives, the introduction of shadow pricing into the measurement of productivity growth. The theory is applied to the case of the Australian National Railways Commission (AN Rail), where excess staff levels, and the delivery of certain ‘community service obligations’ provide examples of the application of shadow prices. Rates of TFP growth are calculated by applying both the traditional formulation and the more general one accommodating any divergence between actual and shadow prices. When shadow pricing is accounted for, the average compound rate of TFP growth in AN Rail falls by up to 37%.  相似文献   

15.
Current modal share in Indian cities is in favor of non-motorized transport (NMT) and public transport (PT), however historical trends shows decline in its use. Existing NMT and PT infrastructure in Indian cities is of poor quality resulting in increasing risk from road traffic crashes to these users. It is therefore likely that the current NMT and PT users will shift to personal motorized vehicles (PMV) as and when they can afford it. Share of NMT and PT users can be retained and possibly increased if safe and convenient facilities for them are created. This shall also have impact on reducing environment impacts of transport system.We have studied travel behavior of three medium size cities – Udaipur, Rajkot and Vishakhapatnam. Later the impact of improving built environment and infrastructure on travel mode shares, fuel consumption, emission levels and traffic safety in Rajkot and Vishakhapatnam are analyzed. For the purpose three scenarios are developed – improving only NMT infrastructure, improving only bus infrastructure and improving both NMT and bus infrastructure.The study shows the strong role of NMT infrastructure in both cities despite geographical dissimilarities. The scenario analysis shows maximum reduction in CO2 emissions is achieved when both PT and NMT infrastructure are improved. Improvement in safety indicator is highest in this scenario. Improving only PT infrastructure may have marginal effect on overall reduction of CO2 emissions and adverse effects on traffic safety. NMT infrastructure is crucial for maintaining the travel mode shares in favor of PT and NMT in future.  相似文献   

16.
This study highlighted significant cultural differences and complexity in travel behaviour associated with travel to university across the UK and Ireland. This paper examines university travel behaviours and the implications for emissions, across the 2012–2013 academic year, based on responses from 1049 students across 17 universities in Ireland and the UK. Surveys were analysed to examine the trips of students both during term time and when accessing the universities each year. The data analysis in this paper examines three aspects of the transport implications of travel to and from university. Firstly the journey between university and term time address (or permanent address if the respondent does not have a separate term time address), secondly the journey between the university area and a separate permanent address where relevant; and thirdly implications for emissions resulting from university-related travel.The study found that student car users were more likely to be female, older students, or studying part time; male students were more likely to use active modes. The study indicated interesting differences between students living in different parts of the UK and Ireland. For example, it was found that there was a higher level of car dependence amongst Northern Irish students compared to other areas; and a greater variability in travel distances in Scotland and Northern Ireland. In England, car use was more pronounced when students travelled from their permanent address to term time address, and, as in Ireland, there was evidence of more car sharing on such trips. Public transport usage was more pronounced amongst Scottish students. The effect of these transport choices on emissions is significant and demonstrates the importance of education related trips to the development of a transport policy response. The analysis shows that annual emissions are highest for regular travel to and from university when a student has a permanent address rather than a separate term time and permanent address.  相似文献   

17.
文章介绍了华蓥山特长瓦斯隧道施工中对有害气体采用的监测依据和标准以及监测方法和监测仪器;论述了对有害气体采取的排放、通风、防护、注浆止气、气密性混凝土等综合治理措施.  相似文献   

18.
无论是城市公共客运、城市出租客运、旅游客运,它都具备了道路旅客运输的基本特点、基本属性,人为地将这一市场割裂,说明现行政策离"群众满意"这个根本出发点还有一定的距离.  相似文献   

19.
Several electrification systems based on renewable energy power sources (first of all, solar energy) are discussed in respect to their applicability to railway transport and, in particular, to suburban electric trains. Two systems are considered with basic technical details and economic estimation, both including the onboard bank of batteries and the photovoltaic converters (PVC) of solar energy for compensation of energy expenses, which could be positioned either on stations or on wagon's roofs. Sun‐tracking systems and their effect on the solar energy conversion efficiency are discussed in application to stationary and moving PVC platforms. An analysis made shows that introduction of the “green” systems discussed will not only have positive ecological impact, but also can bring a notable economical effect even with today's components, while it could be considerably greater with the usage of new PVCs, which are being developed by the authors. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

20.
This article ascertains the viability of promoting accelerated depreciation for newly acquired locomotives and other rolling stock as a means of encouraging technological investment in more efficient and environmentally friendly assets. The study uses a tax-adjusted asset replacement model to evaluate the merits of accelerated depreciation, and then compares the outcomes with alternative incentive schemes. It also examines what would occur if various schemes were used simultaneously.  相似文献   

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