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21.
回顾铰接式列车的应用与发展,分析了铰接式列车的基本结构模式及优缺点;结合城市轨道交通的特点和城轨车辆的基本要求,论证了铰接式转向架在城轨车辆中运用的可行性,并提出了城轨车辆用铰接式转向架的初步设计方案。 相似文献
22.
从影响沥青路面平整度的各个方面查原因、找对策,总结对道路施工平整度的控制,特别是沥青路面施工平整度控制的经验,为公路设计和施工提供一定的参考. 相似文献
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This paper reviews two road-user surveys on the use of mobile phones on the road in Finland where the mobile phone ownership rate is highest in the world (70% in August 2000). From 1998 to 1999 the proportion of drivers that chose to use a mobile phone while driving rose from 56% to 68%, while the proportion of phone using drivers who experienced dangerous situations due to phone use rose from 44% to 50%. The proportion of drivers who used their phones in some way to benefit safety on the road remained at about 55%. The youngest, novice drivers had the highest level of phone usage of all age categories. Over 48% of the interviewees believed that the government should ban the use of hand-held mobile phones while driving, and another 27% believed that all types of mobile phone use should be banned while driving. Those drivers who used their phones the most each day were more likely to want some form of restrictions, than those who had lower usage. This is a strong message to the elected lawmakers and raises the problem of exactly how regulatory bodies would go about controlling the future growth of new driver support and non-driving related communication devices in road vehicles. It was concluded that legislating for hands-free use only would be a reasonable course of action. Mandating that the current generation of equipment should be optimized for hands-free use should result in future generations of in-vehicle equipment also being optimized for hands-free use as a minimum criterion. 相似文献
25.
结合实践经验论述了盐渍土地区公路边坡生物防护技术的意义,介绍了公路边坡生物防护的主要模式、护坡植物的选择原则以及主要的护坡植物类型。 相似文献
26.
城市轨道交通智能综合监控系统设计 总被引:5,自引:0,他引:5
研究目的:城市轨道交通监控系统是运营阶段管理工作的核心,其监控范围的广度和深度直接影响轨道交通运营质量。目前国内的监控系统,关键设备和技术大都从国外全盘引进,很不经济,也造成了隐患。实现监控系统国产化势在必行。
研究方法:本文在分析国内外城市轨道交通运营安全现状的基础上,提出了利用通信、计算机控制技术和人工智能技术,建立城市轨道智能运输系统的基本构想,并进一步提出城市轨道交通智能综合监控系统的设计框架。分析该综合监控系统的内涵、逻辑框架、结构信息流、物理框架和接口技术。
研究结果:跟现有的监控系统相比,智能综合监控系统具有监测范围广、分工明确、实现集中化管理、一体化协调运作和智能化管理的特点,充分体现了以人为本的理念。
研究结论:对于今后国内的城市轨道交通监控系统的建设具有科学的指导意义。 相似文献
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在分析杭州市交通供需现状的基础上,提出了规划多中心结构和混合功能区,以减少不必要的出行以及合理配置交通源,并对改善中心区交通提出切实可行的对策。 相似文献
29.
Hironao Kawashima 《Transportation》1990,17(3):263-284
A perspective view of of Japanese R&D activities of Driver Information Systems is given from the standpoint of developing joint projects by public and private sectors. First, a brief history of the R&D activities is illustrated from above mentioned standpoint. Then, two major projects, AMTICS and RACS, and the social backgrounds of these projects are explained. In order to give a clear idea of both projects some technical details are treated.Based on the history and the present status of the developments, the basic design conceptions of Japanese Driver Information Systems are explained and several factors or reasons which have influenced to the design conception are discussed. Then, the promoting systems of the R&D activities are generally explained and present status of the projects and future problems in developing more advanced systems are also handled. A brief discussion on the establishment of international standard is also mentioned as a final comment. 相似文献
30.
This paper documents an application of panel, or longitudinal data collection in the evaluation of a TSM (Transportation Systems Management) demonstration project. The project was a four-week demonstration of staggered work hours in downtown Honolulu during February–March 1988. The 4 wave panel survey elicited commuting experiences of approximately 2,000 downtown employees at two week intervals before and during the project. The sample involved both employees who participated in the project by shifting their work hours, and those who did not. The panel survey was augmented by floating-car observations of travel times on major routes into downtown Honolulu on the same four dates.The purpose of the analysis was to determine whether employee commute times were affected, and if so, how these changes were distributed among various employee segments. Two methods were used. First, travel time changes were estimated using paired t-tests. Second, regression equations were used to estimate project time savings as a function of trip length, route, and location of residence. Results show that travel time savings due to the project were typically small, less than ten percent. Nonparticipants experienced greater savings than participants, and some segments of participants experienced longer travel times during the project. The panel method proved to be an effective way to measure project travel time impacts and shows that the method is appropriate in short time applications.Presented at the Annual Meeting of Transportation Research Board, January 7–11. 1990, Washington, D.C. 相似文献