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91.
为了优化资源,降低物流成本,提高物流运输可靠度和速度,需要建立恰当的西南公路出海(辅助)通道的物流运作模式,以充分发挥出西南公路出海(辅助)通道基础建设的效益. 相似文献
92.
高速公路交通安全设施工程设计浅析 总被引:1,自引:1,他引:1
针对目前高速公路交通安全设施设计中,技术和设计思想方面存在的问题进行了细致的分析,并结合实践提出了相应的改进建议和意见,为高速公路交通安全设施工程的设计提供合理参考。 相似文献
93.
94.
Municipalities play an important role in the planning and development of communities that support active transportation (AT), which refers to human-powered modes of travel, such as walking and cycling. Municipal-level stakeholders involved in land-use and transportation infrastructure planning consider multiple social, environmental and economic considerations to inform decision-making and investments in AT. Evidence around the fiscal benefits of AT investment for local governments has not been systematically identified. This scoping review sought to explore the existing evidence regarding investments in AT and opportunities for savings on municipal expenditures and revenue generation. In total, 7060 records were located and screened; of which 162 full-text articles were reviewed. Ultimately, 23 articles met our inclusion criteria and were included in this review. The available evidence focuses on potential economic benefits of AT in the areas of tax revenues, property values, consumer spending and employment, all of which are relevant sources of revenue generation in municipal operating budgets. An evidence gap was identified regarding AT infrastructure investments and benefits corresponding to municipal expenditures (e.g. maintenance cost savings). Notably, a large portion of literature was published after 2009, suggesting that municipal-level evidence on the fiscal benefits of AT investments may just be emerging. 相似文献
95.
武汉市过长江交通是武汉市最主要的交通流向之一。根据流量观测数据分析长江交通流量特征,表明武汉市区过长江交通饱和,交通需求总量大,出行目的种类多。过长江交通没有明显、固定的高峰日和高峰小时,除通勤交通外。还有公务等大量非通勤交通。其中武昌与汉口之间交通是主流向,需要适当新增通道缓解过江难问题。 相似文献
96.
信号环境仿真是检验雷达侦察设备性能的重要手段。针对雷达侦察信号环境时域、空域、频域、能域分布特点,对雷达侦察信号环境进行了数学描述,建立了雷达辐射源信号环境数学模型,为雷达侦察信号环境仿真奠定基础。 相似文献
97.
采用以生态适宜性分析为基础的区域生态承载力评价,在地理信息技术的支持下定量获取各评价指标的信息,研究港口工程建设对湿地环境承载力的影响。研究表明,该方法是生态承载力评价方法的有效补充,弥补了生态承载力评价的不足。 相似文献
98.
99.
交调工作是公路规划、建设的重要基础工作,详细地分析了交调工作的意义及河北省开展现状及存在的问题,并提出相应建议。 相似文献
100.
Surrogate indicators are meant to be alternatives or complements of safety analyses based on accident records. These indicators are used to study critical traffic events that occur more frequently, making such incidents easier to analyse. This article provides an overview of existing surrogate indicators and specifically focuses on their merit for the analyses of vulnerable road users and the extent to which they have been validated by previous research. Each indicator is evaluated based on its ability to consider the collision risk, which can be further divided into the initial conditions of an event, the magnitude of any evasive action and the injury risk in any traffic event. The results show that various indicators and their combinations can reflect different aspects of any traffic event. However, no existing indicator seems to capture all aspects. Various studies have also focused on the validity of different indicators. However, due to the use of diverse approaches to validation, the large difference in how many locations were investigated and variations in the duration of observation at each location, it is difficult to compare and discuss the validity of the different surrogate safety indicators. Since no current indicator can properly reflect all the important aspects underlined in this article, the authors suggest that the choice of a suitable indicator in future surrogate safety studies should be made with considerations of the context-dependent suitability of the respective indicator. 相似文献