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21.
From 2012 on, all CO2 emissions from flights departing from or arriving at airports within the European Union have to be offset. We analyze the economic and ecological impacts that are caused by an inclusion of the aviation industry into the proposed emissions trading scheme (ETS). Building on the now fixed system design we employ a simulation model to estimate the impacts of the scheme. Our results indicate that financial impacts are highly dependant on external settings, such as allowance prices and demand growth. We show that the financial burden on the aviation industry will be rather modest in the first years after the introduction of the system and therefore induce only low competition distortions. Likewise, emission reductions within air transportation will be comparably low. While aviation will induce a decline of emissions in other sectors, significant absolute reductions within air transportation can only be reached by a more restrictive system design.  相似文献   
22.
ABSTRACT

While automated vehicle (AV) development continues to progress rapidly, how the public will accept and adopt automated vehicles remains an open question. Using extensive survey data, we apply cluster analysis to better understand consumer perceptions toward potential benefits and concerns related to AVs with regard to factors influencing their AV adoption likelihood. Four market segments are identified – ‘benefits-dominated,’ ‘concerns-dominated,’ ‘uncertain,’ and ‘well-informed.’ A random parameters multinomial logit model is then estimated to identify factors influencing the probability of respondents belonging to one of these four market segments. Among other influences (such as socio-economic and current travel characteristics), it is found that ‘Millennials’ have a higher probability of belonging to the well-informed market segment, ‘Gen-Xers’ with a lower probability to the uncertain market segment, and ‘Baby Boomers’ with a higher probability to the concerns-dominated market (relative to the ‘Great Generation’). We also study the individuals’ expressed likelihood of AV adoption using separate random parameters ordered probit estimations for each of the four market segments. The substantial and statistically significant differences across each AV consumer market segment underscore the potentially large impact that different consumer demographics may have on AV adoption and the need for targeted marketing to achieve better market-penetration outcomes.  相似文献   
23.
Uncertainty of outcome is widely recognised as a concern facing decision-makers and their advisors. In a number of spheres of policy, it appears uncertainty has intensified in the face of globalisation, economic instability, climate change, technological innovation and changing consumer preferences. How can planners and policymakers plan for an uncertain future? There is growing interest in, and use of, techniques that can help decision-making processes where deep uncertainty is involved. This paper is based upon one of the most recent international examples of a foresight exercise employed to examine uncertainty – specifically that which concerns uncertainty over the nature and extent of future demand for car travel. The principal focus of the paper is on the insights and guidance this examination of uncertainty brings forth for transport planning and policymaking. To accommodate deep uncertainty requires a flexible and open approach in terms of how policy and investment possibilities are formulated and judged. The paper argues for a focus upon the Triple Access System of spatial proximity, physical mobility and digital connectivity as a framework for policy and investment decisions that can harness flexibility and resilience. Uncertainty becomes an opportunity for decision-makers with the realisation that they are shaping the future rather than (only) responding to a predicted future. The paper outlines two forms of policymaking pathway: regime-compliant (in which adherence to trends and the nature of the world we have known pushes policy) and regime-testing (in which the nature of the world as we have known it is brought into question and vision pulls policy decisions). Stronger orientation towards regime-testing to assist in managing an uncertain future is advocated.  相似文献   
24.
The objective of this study is to analyse the diurnal rhythms of city life and its spatial differences in Tallinn, using mobile telephone positioning data. The positioning experiment was carried out in April 2006 over an 8-day period and 15-min intervals, with a random sample of 277 respondents living in new residential areas outside the city of Tallinn.The investigation of the space–time movements and daily distances of respondents showed that the majority of respondents had a similar temporal rhythm related to work, school, services and leisure in the city. Because of the different timing of those activities, the mobile positioning data made it possible to map functional differences in the city. The advantages and disadvantages of mobile positioning data in mapping urban life are discussed in the final section of the study.  相似文献   
25.
文章分析了现有道路运输企业质量评价体系的不足,提出了新的道路评价方法,为将来的道路运输管理和规划提供了一个基础。  相似文献   
26.
公路客运峰谷现象明显,在运能、运力有限的情况下,如何才能更好地满足客运高峰期(如春运)的交通需求是政府和企业的一项重要课题。现有的政策并没有使有限的客运资源得到最合理的利用,给能源和环境都带来了一定的影响。文章较系统地从企业和政府两个角度论述了建立班车报停制度的必要性和可行性,通过对客运线路的调查,对公路客运班车报停制度的社会经济效益作了定性和定量分析。  相似文献   
27.
文章针对目前我国公路建设设计变更领域存在的一些问题,从设计变更内容、设计变更种类分析产生问题的原因,就如何更好地规范公路建设设计变更行为,提出了相关建议。  相似文献   
28.
文章针对荔浦县农村客运发展现状,分析了当前农村客运市场发展存在的安全问题,提出了加强荔浦县农村客运市场安全管理的措施,为该县构建安全、和谐的农村客运市场提供思路。  相似文献   
29.
综合介绍了国外汽车发动机、变速器、转向系和悬架等电子技术的发展;分析了目前国内汽车电子产品市场的现状,重点探讨了国内汽车电子产品市场的发展趋势和特点,并作出了细分市场的预测。  相似文献   
30.
AMT换挡品质的研究   总被引:10,自引:3,他引:7  
电控机械式自动变速器(AMT)具有传动效率高、结构紧凑及工作可靠等优点。介绍了AMT换挡品质的定义及其影响因素,分析了几种影响因素之间的内在关系,并在此理论基础上寻求一种可获得最佳AMT换挡品质的方法。AMT按照其对发动机控制方式的不同,可分为柔性控制和刚性控制结构。  相似文献   
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