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31.
Rosenbloom  Sandra 《Transportation》2001,28(4):375-408
In the next three decades there will a huge increase in both the absolute number of older people and in their percentage of the populationin almost all Western European countries, North America, and Australia. Most older people will have active lifestyles in which mobility and access play a major role and almost all older men and a majority of older women will be car drivers, used to the convenience and flexibility which the car provides.Using data from the US, Australia, Germany, New Zealand, Norway, and the United Kingdom, the paper shows that, in spite of cultural and policy differences, older people around the world are more likely to have a license, to take more trips, and to do so more often as the driver of a car than older people just a decade ago; they are also less likely to use public transit. These trends have a number of sustainability implications – the most obvious one is increased environmental pollution. For example, even though older people may travel less than younger drivers they may be polluting proportionately more because a) they are less likely to make as great a proportion of trips in public transit as younger people and b) the trips they do make may create more pollutants. In addition, older drivers may incur more wasted miles due to wayfinding errors and trip-scouting behavior. And when older people curtail their driving, younger family members may have to increase (or lengthen) their trip-making to provide needed services or additional transportation.While this paper stresses the environmental problems posed by an aging population, effective strategies arise from a focus on a broader definition of sustainability. The most important approach is to accept the inevitable and work to make the private car "greener" and safer. New transit service concepts and strategic community and neighborhood design and service elements can complement the development of cleaner cars.Although many of the potential strategies are not new, or can be expensive to implement, the convergence of environmental concerns with other problems arising from the automobility of the elderly – including increasing crash rates and serious loss of mobility among those unable to drive – may make these policies more politically viable than in the past.  相似文献   
32.
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   
33.
结合当前上海轨道交通电梯设备的管理现状及存在的主要问题,提出了建设一套移动化的电梯作业管理与在线监测系统,并从系统的业务架构、功能、移动化内容、配置及性能方面分别进行了阐述。通过作业管理子系统与在线监测子系统的相结合,增强电梯设备的实时监控力度,提高现场作业效率,对地铁电梯运营管理水平的整体提升有参考意义。  相似文献   
34.
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   
35.
徐长明 《天津汽车》2014,(1):13-14,18
乘用车市场的发展态势是各大汽车制造企业关注的焦点,对企业制定发展战略和及时调整产业结构至关重要。在分析2013年乘用车市场逐步走高态势形成原因的基础上,对比美、欧、日等国家的汽车销量和保有水平,对2014年我国乘用车市场需求及发展走势进行了预测。受发展规律、宏观经济及汽车政策的影响,2014年我国乘用车需求预计为1860万辆,同比增长14%。2014年乘用车市场将继续保持平稳快速发展。  相似文献   
36.
分析客车行业的市场现状及政策趋势;对客车行业应重点关注节能和安全标准的实施进行阐述。  相似文献   
37.
本文针对智能交通和主动交通管理提出了一种适用于大规模交通分配和路径规划的分布式计算方法。讨论了通过信息传递接口(MPI)在多中央处理器(CPU)上并行计算实现的一系列研究需求和实现挑战;将基于时空事件的车辆路径规划模型应用于大规模的城市路网仿真;将原始车辆路径规划模型分解为一系列计算效率较高的子问题,大幅减少了仿真耗时和通信开销。通过将子问题分发到单独的分布式CPU上,使CPU可以同时执行其任务,并保证较好的负载平衡。重点分析了将所提出的方法应用于北京路网大规模路径规划,以及该方法在不同CPU核数下的计算效率。结果表明:所提出的并行计算方法可以显著减少计算耗时,并在512个计算节点上实现200倍以上的加速比。  相似文献   
38.
系统论述了中国轿车市场1978--2008年发生的5次波动。通过对前4次波动的研究,提出了新的车市研究方法体系一车市波动分析法,该方法成功预报了第5次波动期的主要阶段。详细介绍了轿车市场第5次波动期的全过程,分析了中国轿车市场波动规律的“井喷”和“余喷”现象,以及2009--2010年轿车市场发展趋势。  相似文献   
39.
近年来,我国的二手车市场不断地发展,逐年呈递增趋势,尤其是在本世纪以来近二十年的时间中,二手车的交易量倍增至近60倍。本文结合我国目前的汽车保有量及近年来二手车市场发展现状,分析目前我国二手车市场的特点,对于未来二手车的前景进行分析。  相似文献   
40.
结合当前形势,分析了中国企业实施走出去战略的优势,指出了中国企业在走向国际建筑市场时将面临的问题及其相应的对策。  相似文献   
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