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61.
高速公路隧道交通安全保障系统的研究 总被引:13,自引:2,他引:11
高速公路隧道交通安全保障系统是一个复杂的动态系统,是对隧道交通安全运行环境的优化,以减少交通事故发生的可能性以及减轻事故的严重程度,提高道路服务水平,保证高速公路隧道的安全行车。本文以京珠高速公路韶关段隧道为例,对高速公路隧道交通事故特点进行分析,并根据人机工程学原理,探讨高速公路的交通事故的致因因素,提出了高速公路隧道交通安全保障系统的设计思路,然后从人性化和可持续发展的角度出发,建立了以静态管理和动态管理相结合的高速公路隧道交通安全保障系统,并探讨了其运作模式,最后分析了该交通安全保障系统的关键技术,以保障高速公路隧道的安全运营的可靠性、先进性、实时性、可用性以及高效性。 相似文献
62.
介绍我国西部公路建设中存在的影响环境保护的几方面问题,提出如何根据各地的自然环境、生态环境、社会经济环境特点,因地制宜地解决好公路建设环境保护问题的几点建议。 相似文献
63.
为解决复杂环境下基坑开挖时下方地铁隧道正常运营的难题,依托郑州某市政管廊上跨地铁区间隧道项目,采用三维数值模拟计算及施工监测数据分析的方法。得出如下结论: 1)通过选取合理的基坑围护方案,可减小基坑围护结构施工对地铁区间隧道的扰动影响; 2)对于工程地质情况较好的地区通过细化上跨基坑开挖方式,采用基底加固+抽条施工的方案可保证地铁区间隧道的正常运营。 相似文献
64.
山区高等级公路选线的几点认识 总被引:1,自引:0,他引:1
根据山岭区的特点提出了对山岭区高等级公路选线的几点认识,总结了在山区高等级公路选线过程中应注重的几个问题。 相似文献
65.
66.
山西平遥至榆社高速公路穿越自然保护区路段的生态环境影响评价 总被引:2,自引:2,他引:2
结合山西平遥至榆社高速公路的环境影响评价工作,通过对拟穿越超山自然保护区路段生态环境现状的调查,论述了公路建设可能对生态环境造成的影响,并提出了相应的措施和建议。 相似文献
67.
Kelly J. Clifton Carolina V. Burnier Gulsah Akar 《Transportation Research Part D: Transport and Environment》2009,14(6):425-436
This paper examines the impact of personal and environmental characteristics on severity of injuries sustained in pedestrian–vehicle crashes using a generalized ordered probit model. The data covers 2000–2004 of pedestrian–vehicle crashes taken from police incident reports for Baltimore City and supplemented with local land use, urban form and transportation information specific to the individual crash locations. The results on personal and behavioral variables confirm previous findings. Women pedestrians involved in crashes tend to be injured less frequently than their male counterparts; children have an increased likelihood of sustaining injuries and older persons are more likely to be fatally injured. Pedestrians who cross against the traffic signal, are not in a crosswalk and are involved in a crash after dark are associated with greater injury risk. Of the built environment policy variables of interest, transit access and greater pedestrian connectivity, such as central city areas, are significant and negatively associated with injury severity. These results suggest that the environmental conditions should be given more scrutiny and be an important consideration when evaluating and planning for pedestrian safety. 相似文献
68.
69.
Zhibin Li Wei WangPan Liu David R. Ragland 《Transportation Research Part D: Transport and Environment》2012,17(3):256-261
This study investigates the impacts of physical environments on bicyclists’ perceptions of comfort on separated and on-street bicycle facilities. Based on a field investigation conducted in Nanjing, China, we find that physical environmental factors significantly influencing bicyclists’ perception of comfort on the two types of facility. Cyclists’ comfort is mainly influenced by the road geometry and surrounding conditions on physically separated paths while they pay attention to the effective riding space and traffic situations on on-street bicycle lanes. 相似文献
70.
Tiago A. Santos 《Maritime Policy and Management》2017,44(7):859-881
A novel methodology is developed for determining the characteristics of a cargo roll-on/roll-off (ro-ro) ship and the fleet size required for a given short sea shipping route. The ship and required fleet size to satisfy the transportation demand (for each pair of speed and freight rate) are determined using a database of existing cargo ro-ro ships to obtain the main technical characteristics of the most suitable ship. The time charter, voyage costs and revenue are then calculated considering the technical characteristics of each ship. Fuel costs are corrected for the actual ship speed and loading condition. A number of restrictions in the transportation problem are considered leading to the exclusion of unfeasible solutions. The maximum profit over the period of a year is identified among the feasible pairs of speed and freight rate. This general methodology is applied in a case study that considers the route between Leixões (Portugal) and Rotterdam (Netherlands). The study allows the identification of the most suitable ship and fleet sizes for different market penetration levels and quantifies the impact on shipping company profit of changes in parameters such as fuel costs, time charter costs, emission control area, installed propulsion power and stacking factor. 相似文献