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341.
Zia Wadud 《Transportation Research Part A: Policy and Practice》2011,45(10):1052-1065
Personal road transport sector poses a significant challenge in reducing carbon emissions. This paper evaluates a policy approach known as personal tradable carbon permits to reduce carbon emissions from personal vehicles. The policy is a downstream tradable permit where individuals are allocated carbon emission caps. The policy is qualitatively evaluated in the context of carbon taxes and some upstream tradable permit options. The biggest disadvantage of such a policy is the initial set up costs. Personal tradable permits, however, are more effective than carbon taxes and are also capable of stabilizing the gasoline prices faced by the consumers when the underlying oil prices fluctuate. Since equity effects are often a concern to policy makers, the effect of such personal carbon permits on the distribution of burden is quantified in a partial equilibrium framework for the US population. Different permit allocation strategies are investigated in this regard. Using US consumer expenditure survey data, and incorporating a differentiated price response for different households, we find that all three allocation strategies considered are progressive: a per adult based allocation is the most progressive, a per vehicle allocation nearer to proportional, and a per capita allocation in between the two. Personal tradable permits therefore take care of equity concerns directly through the design of the policy. 相似文献
342.
John K. Stanley David A. Hensher 《Transportation Research Part A: Policy and Practice》2011,45(10):1020-1030
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
343.
文章介绍了坛厂隧道施工中存在的主要工程地质问题(浅埋破碎、煤层瓦斯、断层破碎带、岩溶及涌水突泥等),以及地质超前预报的重点和难点;针对施工中采用的“以地质法为基础、以HSP声波反射法为主要手段、结合电磁波反射法的综合预报技术”,并结合隧道进口浅埋段和中部岩溶涌水突泥段的预报情况进行了研究分析.隧道施工开挖揭露的情况表明,预报结果与实际开挖揭示吻合率较好,对本隧道工程施工起到了积极的指导作用,为隧道安全施工提供了技术保障. 相似文献
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喷油器是柴油机的关键部件,它易产生的故障有:滴油、针阀咬死、针阀与针阀导向面磨损、喷孔扩大、喷油器雾化不良、用错针阀偶件、针阀体的端面磨损、喷油器与缸盖结合孔漏气窜油等。详细分析了这些故障产生的原因,并提出了排除故障的方法。 相似文献
346.
王金胜 《筑路机械与施工机械化》1992,9(2):37-39
本文浅谈了在制定筑路机械燃油消耗定额时应考虑的几个因素,给出了测定计算机械台班油耗定额的参考计算公式。 相似文献
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介绍了在公路沥青混凝土搅拌设备上以煤粉为燃料的优点及应用前景。进行了经济性分析,介绍了配套设备煤燃烧器的情况,通过对比分析提出存在的一些问题,以进一步研究应用。 相似文献
350.