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51.
文章从合理性的一般哲学解释出发,论证出综合交通线网规划方案合理性存在的必然性,然后分别从多方式合理分工、各交通线路分阶段整体推进、交通线网投资实施总体控制、交通网络构建符合OD分布规律、以及线网规划目标考虑资源消耗限制等方面,深入分析合理的综合交通体系应具备的特征,并由此推荐系列评价指标集,从而为综合交通线网规划方案合理性评价提供理论依据。 相似文献
52.
The impact of major road developments on the spheres of urban influence of Japanese cities 总被引:1,自引:0,他引:1
This study aims to measure the impact of major road developments on the spheres of urban influence of Japanese cities.First, the sphere of urban influence is defined by application of an individual behavior model. The model explains the number of trips to representative cities in regions from the residential place of each individual using the following factors; the attractiveness of cities, the travel time to cities and the individual's free time. Development of major roads shortens the travel time, and this causes the change in the sphere of urban influence. The model we propose has the structure to explain this phenomenon.Second, this method is applied to all of Japan where expressways are now being rapidly constructed and, how they change spheres of urban influence is explained. In the application, as a measure of attractiveness of cities, population, commercial and industrial activity, etc. are considered. From these points of view, the impacts of construction of expressways in Japan are estimated. 相似文献
53.
通过对隧道开挖过程进行三维数值模拟,分析了隧道开挖过程中主应力方向的旋转变化,研究了主应力旋转与隧道裂隙塑性变形的关系,验证了"考虑应力主轴旋转的广义塑性原理"的正确性,并将数值模拟结果和相关试验成果进行了对比,得出了一致性的结论。研究结果表明,应力旋转基本在隧道开挖前后10 m左右的距离内完成,隧道开挖过程中的应力旋转可以引起裂隙塑性变形的突变,且对竖向和斜向裂隙的影响较大;可以根据应力旋转的变化规律合理地选择支护时机,依据应力旋转对裂隙的影响对隧道的重点部位进行超前加固。 相似文献
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文章以西部某交通勘察设计企业为研究对象,对当前交通勘察设计企业所面临的内外部形势进行分析,并针对企业转型发展中所存在的问题,提出以创新为驱动的发展模式,总结归纳出推动企业可持续发展的相关对策,对类似交通勘察设计企业的转型发展具有一定的参考和指导意义。 相似文献
56.
This paper discusses the evolving institutional structure and governance of transportation planning, policy development and transit delivery within one major North American city-region, the Greater Vancouver area. Various methods of transportation governance are explored from complete independence to full regional integration. The move away from a direct provincial role in transportation management to a greater regional transit authority is discussed and critiqued. This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
57.
Hartmut H. Topp 《Transportation》1988,15(4):279-295
West Germany is densely populated, averaging 245 inhabitants/km2, but varying widely between urban agglomerations and rural areas. Transport volume has increased by 40% since 1970, with virtually all growth due to private automobiles. Since 1981 public transit has been suffering from decreasing demand.A 1964 Expert's Report to the German federal government was the stimulus for initiating an effective funding mechanism for new public transit construction. In 1965 Germany's first federated transit authority was founded for the region of Hamburg.Principal among the goals of any cooperative agreement among transit companies are improvements for the passengers and improvement of revenues for the companies. To attain these ends, two distinct forms of transit aggrements have been developed in Germany: transit cooperative (Verkehrsgemeinschaft) and transit federation (Verkehrsverbund). The former is more suitable for smaller to medium-sized towns, while the latter is more suitable for larger cities. The two types are described in this article.German transit federations during the 1970s succeeded in significantly increasing ridership, while during the 1980s patronage has either remained steady or has declined. Yet transit federations showed much better perfomance than did public transit in general. In terms of costs and revenues, no public transit organization in Germany is able to break even; deficits vary between 42% and 55%. The author concludes, however, that hidden subsidies for automobile traffic are far higher, because of environmental damage and the high social cost of traffic accidents. 相似文献
58.
基于对智能交通系统(ITS)最基本要素——交通信息采集技术的研究,以及对常用车辆检测器进行的分类、分析和研究,阐述固定型检测技术中较为典型的几种车辆检测器工作原理,分析各自的优势、不足和适用环境。结合当今科技的发展趋势及ITS的发展需求,分析探讨道路交通车辆检测技术的发展方向和交通信息融合技术。 相似文献
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60.
国Ⅳ之后柴油机三种燃油喷射系统对比及其技术发展趋势 总被引:1,自引:0,他引:1
系统地介绍了电控泵喷嘴系统、电控单体泵系统、电控共轨系统的结构及牛寺|点。阐述了电控燃油喷射系统的技术发展趋势。 相似文献