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991.
The objective of this paper is to ease the planning of new toll projects by providing estimates of operating costs, and to
help us make better informed decisions about the design of toll collection systems. To do so we use panel data for Norwegian
toll companies to estimate average cost functions. The main results can be summarised as follows. We provide evidence of very
important unexploited economies of scale. The estimated cost curves are very steep for traffic levels below the sample mean,
and become almost entirely flat over a wide range above the sample mean. A higher share of vehicles using on board units will
significantly reduce average costs. Competitive tendering will significantly reduce average operating costs by as much as
25%. Our results also suggest that increased number of lanes, higher debt and passenger charging will increase average operating
costs whereas average operating costs are lower for toll cordons compared with other projects.
相似文献
Morten WeldeEmail: |
992.
Despite widespread growth in on-road public transport priority schemes, road management authorities have few tools to evaluate
the impacts of these schemes on all road users. This paper describes a methodology developed in Melbourne, Australia to assist
the road management authority, VicRoads, evaluate trade-offs in the use of its limited road-space for new bus and tram priority
projects. The approach employs traffic micro-simulation modelling to assess road-space re-allocation impacts, travel behaviour
modelling to assess changes in travel patterns and a social cost benefit framework to evaluate impacts. The evaluation considers
a comprehensive range of impacts including the environmental benefits of improved public transport services. Impacts on public
transport reliability improvements are also considered. Although improved bus and tram reliability is a major rationale for
traffic priority its use in previous evaluations is rare. The paper critiques previous approaches, describes the proposed
method and explores some of the results found in its application. A major finding is that despite a more comprehensive approach
to measuring the benefits of bus and tram priority, road-space reallocation is difficult to economically justify in road networks
where public transport usage is low and car usage high. Strategies involving the balanced deployment of bus and tram priority
measures where the allocation of time and space to PT minimises negative traffic impacts is shown to improve the overall management
of road-space. A discussion of the approach is also provided including suggestions for further methodology development.
相似文献
Bill YoungEmail: |
993.
994.
995.
乳化沥青在道路养护中的应用 总被引:1,自引:0,他引:1
详细论述了应用乳化沥青进行路面养护及发展情况,举例说明了乳液的生产情况、乳液的配方、乳液的各种撒布和乳液在道路养护中的应用情况。 相似文献
996.
997.
温拌沥青混合料是一种节能环保型路面新材料,在室内对掺sasobit添加剂的温拌沥青混合料的路用性能与普通热拌沥青混合料进行了对比试验研究,结果显示:掺Sasobit的温拌沥青混合料的拌和与压实温度比普通热拌沥青混合料降低30℃时,具有与普通热拌沥青混合料相同甚至更好的路用性能,具有明显的经济和社会效益;拌和与压实温度的降低,混合料发生水损害的可能性会增加,建议采用添加抗剥落剂等方法来改善掺Sasobit的温拌沥青混合料的水稳定性;此外,Sasobit掺量过多会对混合料低温抗裂性能有不利影响。 相似文献
998.
999.
有效、快速的道路状况自动识别对于提高ABS性能具有重要意义。通过仿真试验分析,提出了一种比传统方法更快更高效的路面识别方法,并设计了以滑移率为控制目标的ABS模糊神经网络控制器。结合车辆模型熏对单一附着系数路面和变附着系数路面进行了ABS制动模拟试验。结果表明熏基于路面自动识别ABS模糊控制系统能快速、准确判断出路面状况的变化熏自动调整、优化控制器控制参数熏使车辆获得最大地面制动力,与传统利用车身加速度进行路面识别的逻辑门限控制器相比,该控制器反应更灵敏,控制更精确。 相似文献
1000.