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181.
关于城市道路规划设计几个问题的探讨   总被引:1,自引:0,他引:1  
本文主要论述城市道路规划设计应正确认识道路环境、道路功能、重视道路等级与里程长度以及路口与路段通行能力的协调配合。  相似文献   
182.
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   
183.
交通是能源消纳的重要领域,其对社会能源结构的调整和节能减排具有重要的影响和带动作用。在陆路交通方面,轨道交通和小型客运车辆的电气化发展方向相对清晰,而公路货运尚无明确的技术路线。为充分利用清洁能源,减少化石能源在交通领域中的使用,发展并推广电气化公路技术,对重载卡车的蓄电池、燃料电池、混合动力3种电气化方案进行对比分析,结合卡车负载的特点,对不同电气化方案进行评估。研究融合新能源发电及并网、混合动力技术、智能驾驶技术的电气化公路技术,从车辆动力技术、供电线路、受电弓与计费、新能源并网、编组智能驾驶运行5个方面对电气化公路方案进行介绍,可以实现公路货运系统的绿色、安全、高效运行。以10公里线路电气化为例,进行规划和成本估算,构建单车和区域(或路段)电气化的运营成本计算模型,基于燃油消耗和阻力分析2种方法进行计算。对车辆购置及改装、基础设施建设、可再生能源发电、系统环保效益等4个方面进行技术分析与成本测算。从供能技术变革、商业模式和推广路线3个角度对电气化公路技术的未来推广进行论证展望。研究结果表明:电气化公路技术的应用与规模化能够带来巨大的经济与环境收益,其中的混合动力方案与架空线输电方案为面对未来可能的储能技术变革与无线输电普及打下重要的基础,提供了拓展空间,也是重载货车实现智能驾驶的重要步骤;与燃油驱动相比,电驱动百公里成本减少96元,单一重卡年运营成本减少18.8万元,百公里污染物(如:碳氧化物、氮氧化物等)均减少50%以上。  相似文献   
184.
城市综合交通调查在中国已有30余年的广泛实践,当前的信息化和大数据背景下正历经发展与变革.在分析城市综合交通调查现状问题的基础上,提出制定《城市综合交通体系规划交通调查导则》(以下简称《导则》)的必要性.从目标与总体框架、调查项目分类、术语定义、调查内容与问题选项分类、调查流程规范几个层面对《导则》的主要思想与关键内容进行解析.提出城市综合交通调查未来发展方向应是将信息化技术与传统调查手段结合,提高调查效率与质量,关注信息化手段未能涵盖的交通特征.  相似文献   
185.
Characteristics of the built environment (BE) have been associated with walk, transit, and bicycle travel. These BE characteristics can be used by transportation researchers to oversample households from areas where walk, transit, or bicycle travel is more likely, resulting in more observations of these uncommon travel behaviors. Little guidance, however, is available on the effectiveness of such built environment oversampling strategies. This article presents measures that can be used to assess the effectiveness of BE oversampling strategies and inform future efforts to oversample households with uncommon travel behaviors. The measures are sensitivity and specificity, positive likelihood ratio (LR+), and positive predictive value (PPV). To illustrate these measures, they were calculated for 10 BE-defined oversampling strata applied post-hoc to a Seattle area household travel survey. Strata with an average block size of <10 acres within a ¼ mile of household residences held the single greatest potential for oversampling households that walk, use transit, and/or bicycle.  相似文献   
186.
国内目前针对中小城市公交场站的研究不足,中小城市场站建设缺乏科学指导,场站用地难以得到保障.结合中小城市公交发展特点及场站模式,通过科学的分析计算,确定场站停车坪、建筑用地、场前区及绿化用地规模,探讨与之相符的中小城市公交场站用地指标,对于中小城市场站规划建设具有一定的现实意义.  相似文献   
187.
越来越多的机构开始为交通系统的可持续发展定义,并试图将这一概念融入区域交通规划过程.然而,只有极少数的区域规划机构意识到了交通系统和土地利用变化给经济、环境和社会生活质量(这三者通常被认为是可持续交通系统的三个基本方面)带来的广泛影响.首先,论述了使用多个可持续发展指标的多准则决策方法,并应用其评估亚特兰大大都市区的三...  相似文献   
188.
This article provides results on the net benefits generated from the natural resources in the Bohol Marine Triangle (BMT) in the Philippines. The BMT spans over 112,000 ha and its coastal ecosystems are rich in biodiversity and provide economic opportunities to the coastal communities. With a 10% discount rate, the accumulated total net benefits for the BMT resources over a 10-year period is US$11.54 million. Tourism and the municipal fisheries are the most important direct use values of the coastal and marine resources of the BMT accounting for 44% and 39% of the total net benefits. Annual revenues attributed to ecosystems were as follows: coral reefs, US$1.26 million; beach/intertidal area, US$1.12 million; marine waters, US$646,501; mangrove, US$239,561; and seagrass, US$105,990. The large market values indicate the dependence of the local community on the BMT coastal and marine resources. In the same way, non-market values show the important life-support functions of coastal and marine ecosystems. The net benefits reflect the magnitude of potential losses due to improper management of coastal and marine resources in the BMT. This valuation highlights the importance of the coastal services to the BMT economy and draws attention to the benefits the local stakeholders derive from BMT coastal resources. Policy measures can now take into account these values to justify a sufficient investment in coastal management efforts to sustain the flow of coastal services in the interest of current and future generations.  相似文献   
189.
发动机的正常运转与发动机冷却液密不可分,本文主要探讨了乙二醇型汽车发动机冷却液的科学检测和正确使用。发动机冷却液,俗称防冻液,是发动机正常运转不可缺少的散热介质,能保持发动机在最有利的工作温度范围内运行,避免因发动机温度过高或过低带来的不良后果。根据发动机运行的情况对冷却液进行科学的检测、正确的使用和更换会直接影响发动机的使用寿命。  相似文献   
190.
简要介绍了汽车综合性能检测站的全自动检测网络的设计、网络系统的结构形成、系统的软、硬件配置等。  相似文献   
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