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981.
公铁客运格局的变化和演进趋势表明,高速公路网络的形成使其客运规模经济效应出现顶峰;铁路建设也一样,需要一个相对完善的系统才能发挥铁路客运的网络效应,故需要同步推进铁路网络、铁路客运枢纽、铁路与其他交通网络系统衔接的建设。  相似文献   
982.
孙军先 《铁道建筑》2020,(5):139-144
规划年度(2030年)合肥枢纽将形成衔接9个方向、13条线路的大型放射状枢纽.但随着沿江高速铁路建设的提前,沿江高速铁路与既有沪蓉铁路在枢纽内共通道能力是否满足需求、枢纽的客运系统布局和客运站分工是否合理、引入车站站型方案是否最优是面临的关键问题.本文根据研究年度(近期2035年、远期2045年)的枢纽客运量及车流特点,结合既有沪蓉铁路的功能定位及分工调整,对枢纽内主要客运站和区段能力进行分析,对引入车站站型进行研究.通过定量和定性分析,从契合城市总体规划、运输组织的便捷性、线路平面条件、工程实施难易度、工程建设条件、投资等多方面综合比选,优化了枢纽的客运系统布局和客运站分工,确定了合理的枢纽引入方案.  相似文献   
983.
朱鸿娟 《北方交通》2012,(10):108-110
阐述了行政强制的基本概念、设定依据和种类,并针对道路运输行业管理的实际,分析《行政强制法》对道路运输管理的影响及在道路运输行政执法中行政强制的应用问题,着力解决道路运输行政执法难问题。  相似文献   
984.
ObjectivesEvidence concerning crash risk for older heavy vehicle drivers is sparse, making it difficult to assess if it is prudent to encourage older drivers to remain in the workforce in a climate of labour shortages. The objective of this study was to estimate annual crash rate ratios of older male heavy vehicle drivers relative to their middle aged peers.MethodsData utilized in this study includes all crashes meeting inclusion criteria involving heavy goods vehicles, categorised as rigid trucks and articulated trucks; this data was recorded by the New South Wales Roads and Traffic Authority. The exposure to the risk of a crash was represented by distance travelled for each vehicle type and year, by age of driver, as estimated by the Australian Survey of Motor Vehicle Use. Negative binomial regression modelling was applied to estimate annual crash incidence rate ratios for male drivers in various age groups.ResultsA total of 26,146 crashes occurred in New South Wales during 1999–2006, involving a total of 54,191 vehicles; removing observations that did not meet the inclusion criteria, 19,736 observations remained representing 12,501 crashes. For rigid trucks, the incidence rate ratio for drivers aged 65+ years, compared to 45–54 year olds, was 0.74 (95% CI 0.51, 0.98). For articulated trucks, the annual crash incidence rate ratio for drivers aged 65+ years compared to 45–54 year olds was 1.4 (95% CI 0.96, 1.9), and that for drivers aged 55–64 years compared to 45–54 year olds was 1.1 (95% CI 0.83, 1.3).ConclusionsOlder male professional drivers of heavy goods vehicles have lower risk of crashes in rigid vehicles, possibly due to accrued driving experience and self-selection of healthy individuals remaining in the workforce. Thus, encouraging these drivers to remain in the workforce is appropriate in the climate of labour shortages, as this study provides evidence that to do so would not endanger road safety.  相似文献   
985.
Highway traffic flow phenomena involve several complex and stochastic variables with high interdependencies. The variations in roadway, traffic and environmental factors influence the traffic flow quality significantly. Capacity analysis of road sections under different traffic and geometric conditions need to quantify the vehicles of widely varying characteristics to a common and universally acceptable unit. Passenger car unit (PCU) is the universally adopted unit of traffic volume, keeping the passenger car as the ‘standard vehicle’ with reference to its static and dynamic characteristics; other vehicles are expressed to its equivalent number in terms of PCUs. The studies carried out in this aspect represent the dynamic nature of impedance caused by a vehicle while moving through a traffic stream. The PCU values recommended by the Highway Capacity Manual are widely applied in many countries; however, their applicability is highly under debate because of the variations in prevailing local traffic conditions. There are several factors that influence the PCU values such as traffic, roadway, vehicle, environmental and control conditions, etc. Apart from vehicular characteristics, the other two major factors that influence the PCU of vehicles are the following: (i) road width and (ii) traffic volume. In this study, estimation of PCU values for the different types of vehicles of a highly heterogeneous traffic on 7.5‐ and 11.0‐m‐wide roads, using micro‐simulation technique, has been dealt with. It has been found that the PCU value of a vehicle type varies significantly with variation in road width and traffic volume. The results of the study indicate that the PCU values are significantly influenced by the said two factors. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
986.
空气悬架系统作为高档公路大客车的关键部件,已经在国外高档客车上普及,商用车上使用的比例也在迅速提升,其独特的变刚度、低振动频率、抗道路凹凸冲击等诸多优越性越来越受人们重视。目前国内没有一家企业能设计出成熟的产品,加快空气悬架的设计研发,尤其是电子控制空气悬架(ECAS)的研发是大势所趋,谁先掌握了汽车空气悬架的开发技术,谁先开发出配置空气悬架的成熟车型,谁就掌握了今后若干年内商用车市场的先机和主动。  相似文献   
987.
This paper focuses on the effects of deregulation of motor carriers in Australia. It is particularly concerned with the implications of regulatory reform beyond the transport sector and uses a general equilibrium approach to examine the economy wide effects of deregulation. Among other things the paper shows that the effects of deregulation are not evenly distributed across all types of industries. Furthermore it concludes that the magnitude of the effects from deregulation in any given industry is not necessarily correlated with the share of total costs devoted to the purchase of transportation services.

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988.
Charging infrastructure requirements are being largely debated in the context of urban energy planning for transport electrification. As electric vehicles are gaining momentum, the issue of locating and securing the availability, efficiency and effectiveness of charging infrastructure becomes a complex question that needs to be addressed. This paper presents the structure and application of a model developed for optimizing the distribution of charging infrastructure for electric buses in the urban context, and tests the model for the bus network of Stockholm. The major public bus transport hubs connecting to the train and subway system show the highest concentration of locations chosen by the model for charging station installation. The costs estimated are within an expected range when comparing to the annual bus public transport costs in Stockholm. The model could be adapted for various urban contexts to promptly assist in the transition to fossil-free bus transport. The total costs for the operation of a partially electrified bus system in both optimization cases considered (cost and energy) differ only marginally from the costs for a 100% biodiesel system. This indicates that lower fuel costs for electric buses can balance the high investment costs incurred in building charging infrastructure, while achieving a reduction of up to 51% in emissions and up to 34% in energy use in the bus fleet.  相似文献   
989.
陆单  吴青  万剑 《交通与计算机》2009,27(4):109-112
分析了不利天气下道路安全状况评估参数及其影响因素,确定了车载路况采集系统的功能,设计了由道路能见度检测、道路环境温湿度检测、路面状况识别、路面微观形貌检测、路况数据定位与路况数据无线传输6个子系统以及检测车、电源系统等组成的路况检测系统,分析了系统设计中的一些关键技术。  相似文献   
990.
根据多年驼峰气动系统的工作经验,对现代化驼峰气动调速设备动力系统的能耗问题进行多方面的分析,并由此提出节约能耗的方法和手段,为路内各编组站驼峰气动系统的节能工作提供一定的参考和帮助。  相似文献   
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