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111.
112.
唐莉 《重庆交通大学学报(自然科学版)》2012,31(Z1):603-606,723
广阳岛环岛路的主要功能是服务性景观路,跟环岛滨江公园一起,共同构筑广阳岛的滨江景观带。尝试引进了国外的宁静化设计,尽可能推行最生态的工程做法,努力创造人与自然相和谐的环境,并竭尽全力地将这些构想付诸实施。为了实现以上目标,道路、交通、排水、结构、桥梁和电照专业,在景观专业的组织下,共同展开了这条景观路的设计尝试。 相似文献
113.
Among the natural hazards that threaten transportation infrastructure, flooding represents a major hazard to highways as it challenges their design, operation, efficiency and safety. In extreme cases, it may lead to massive obstruction of traffic and direct damages to the road structures themselves and indirect damages to the economic activity and development of the region. To enable the prevention of such consequences, and the proposition of adaptive measures for existing infrastructure, this paper presents an integrated framework to identify the most vulnerable points to flooding along a highway. This is done through the combination of remote sensing information (e.g. LiDAR based Digital Elevation Model, satellite imagery), a high-quality dataset, and a quasi-2D hydrodynamic model. The forcing condition is defined using a hyetograph associated to a storm with duration of 1 day and return period of 100 years. The selected highway is located in the Mexican state of Tabasco, where extreme precipitation events and floods are frequent. Results demonstrate the ability of the methodology to identify critical water levels along the road (h > 1.50 m) at those locations where flooding has been experienced, as well as points of inspection for the highway drainage. These locations were visited in the field and maintenance problems were detected that do increase its level of exposure. We show that this framework is useful for the generation of a flood management strategy to the analyzed highway, which includes an optimum location of adaptive measures to an anticipated more intense future climate. 相似文献
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一种新型管道机械接头密封分析 总被引:1,自引:0,他引:1
随着海洋石油事业的发展,尤其是在役多年的石油平台工艺管道长时间受腐蚀介质和海洋环境的影响容易发生泄漏,传统的管道焊接技术由于需要动火作业,在已投产的石油平台管道维修方面受油气易燃易爆等各种因素的制约,不适应海洋平台管道维修快速、环保、经济等新要求。文中利用ANSYS有限元软件对传统机械接头的结构进行优化分析,开发出一种新型管道机械连接接头。此种接头具有耐高压、耐腐蚀、节能、安全、安装快捷等显著优点,特别适用于海洋石油平台工艺管道的快速维修。着重分析了新型管道机械接头的基本结构、连接机理及影响其密封性能的主要因素,分析结果显示此种连接可靠。 相似文献
116.
Intermodal rail/road transportation combines advantages of both modes of transport and is often seen as an effective approach for reducing the environmental impact of freight transportation. This is because it is often expected that rail transportation emits less greenhouse gases than road transportation. However, the actual emissions of both modes of transport depend on various factors like vehicle type, traction type, fuel emission factors, payload utilization, slope profile or traffic conditions. Still, comprehensive experimental results for estimating emission rates from heavy and voluminous goods in large-scale transportation systems are hardly available so far. This study describes an intermodal rail/road network model that covers the majority of European countries. Using this network model, we estimate emission rates with a mesoscopic model within and between the considered countries by conducting a large-scale simulation of road-only transports and intermodal transports. We show that there are high variations of emission rates for both road-only transportation and intermodal rail/road transportation over the different transport relations in Europe. We found that intermodal routing is more eco-friendly than road-only routing for more than 90% of the simulated shipments. Again, this value varies strongly among country pairs. 相似文献
117.
Recently, there has been a surge of interest in Tradable Credits (TC) as an alternative measure to manage the growth of personal car use. This paper summarises the results and methodologies of studies that have sought to anticipate the behavioural responses to several proposed TC schemes that target personal travel. In a critical reflection on this work and in an attempt to inspire future research, we argue that future empirical studies on TC behaviours can greatly benefit from insights from the fields of behavioural economics and cognitive psychology. Therefore, in the second part of the paper, we bring together behavioural concepts from these fields that are relevant in a TC decision-making context. Based on observations from current TC studies and the behavioural mechanisms identified in the second part of the paper, we propose promising directions for future research on understanding the impact of TC on personal car travel. 相似文献
118.
结合道路运输行业安全监管现状,从道路运输行业安全监管职责和内容、监管方式、安全检查方面对道路运输行业安全监管存在的问题进行分析,并有针对性的提出了相应的建议和对策。 相似文献
119.
交通安全,涉及到人、车以及道路和环境等很多因素。近年来,因为各种原因使得有关单位以及人员将更多的将精力放在人、车、道路这几个因素上,对道路交通环境没有过多的考虑和研究。深入研究道路交通环境,有利于道路交通的安全,文章通过对其的研究和分析,得出有关道路交通环境对交通安全的影响和解决措施,对于防止道路交通安全事故具有重要意义。同时为人们的生命财产的安全提供保障、对构建社会主义和谐社会具有很大帮助。 相似文献
120.
潘美风 《电力机车与城轨车辆》2020,(2):24-27
文章通过结构分析介绍了CRH1A型动车组行李架的关键创新技术以及行李架的研发过程,阐述如何将轻量化、模块化、经济性、维护性综合地运用到动车组产品设计中,通过产品生产制造安装、静强度试验、振动冲击试验证明了优化设计的合理性和有效性。 相似文献