排序方式: 共有138条查询结果,搜索用时 968 毫秒
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地铁在故障情况下运行时,行车调度员通常需要通过人工铺画运行图对列车运行状态进行监控,而人工画图效率低下,列车运行安全也难以保证。因此,在地铁行业急需开发一套地铁列车辅助报点系统,以提高行车调度员在信号系统故障情况下监控列车运行的效率,确保地铁列车运行安全。文章以ASP技术为基础,使用VBScript语言,结合MySQL数据库及ECharts控件实现地铁列车辅助报点系统的开发,针对其中几个关键技术进行较为深入的研究,最后通过南京地铁S8号线对该系统进行设计验证。 相似文献
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杜道军 《筑路机械与施工机械化》1999,16(2):18-20
针对近年来水泥路面施工中使用的一种三辊轴式整平机所存在的不足之处,进行了改进设计并增加了某些功能,使之成为结构简单,实用性更强,操作更简便的水泥路面摊铺抹平机。重点从前行走辊加装偏心体,以弹性悬吊结构安装前行走辊,增设振动抹光平板和安装自助式转向装置方面作以介绍 相似文献
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论述了包西(包头至西安)客货共线隧道在复杂地质条件下的设计技术问题,并对各类复杂地质条件下的处理措施进行了阐述,为以后类似工程提供借鉴和参考。 相似文献
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介绍"油改电"技术的发展,分析、比较几种低架"油改电"插拔取电技术的优缺点,说明电动自动插拔式轮胎吊低架"油改电"系统通过开发和应用全新的结构,从根本上解决了传统低架"油改电"系统存在的许多问题,具有很好的推广应用效果。 相似文献
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Kai Wei Yinling Dou Feng Wang Pengbo Niu Ping Wang 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(12):1838-1863
A hybrid Spectral Element Method (SEM)–Symplectic Method(SM) method for high-efficiency computation of the high-frequency random vibrations of a high-speed vehicle–track system with the frequency-dependent dynamic properties of rail pads is presented. First, the Williams-Landel-Ferry (WLF) formula and Fractional Derivative Zener (FDZ) model were, respectively, applied for prediction and representation of the frequency-dependent dynamic properties of Vossloh 300 rail pads frequently used in China's high-speed railway. Then, the proposed hybrid SEM–SM method was used to investigate the influence of the frequency-dependent dynamic performance of Vossloh 300 rail pads on the high-frequency random vibrations of high-speed vehicle–track systems at various train speeds or different levels of rail surface roughness. The experimental results indicate that the storage stiffness and loss factors of Vossloh 300 rail pad increase with the decrease in dynamic loads or the increase in preloads within 0.1–10,000?Hz at 20°C, and basically linearly increase with frequency in a logarithmic coordinate system. The results computed by the hybrid SEM–SM method demonstrate that the frequency-dependent viscous damping of Vossloh 300 rail pads, compared with its constant viscous damping and frequency-dependent stiffness, has a much more conspicuous influence on the medium-frequency (i.e. 20–63?Hz) random vibrations of car bodies and rail fasteners, and on the mid- (i.e. 20–63?Hz) and high-frequency (i.e. 630–1250?Hz) random vibrations of bogies, wheels and rails, especially with the increase in train speeds or the deterioration of rail surface roughness. The two sensitive frequency bands can also be validated by frequency response function (FRF) analysis of the proposed infinite rail–fastener model. The mid and high frequencies influenced by the frequency-dependent viscous damping of rail pads are exactly the dominant frequencies of ground vibration acceleration and wheel rolling noise caused by high-speed railways, respectively. Even though the existing time-domain (or frequency-domain) finite track models associated with the time-domain (or frequency-domain) fractional derivative viscoelastic (FDV) models of rail pads can also be used to reach the same conclusions, the hybrid SEM–SM method in which only one element is required to compute the high-order vibration modes of infinite rail is more appropriate for high-efficiency analysis of the high-frequency random vibrations of high-speed vehicle–track systems. 相似文献
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沥青面层冷再生技术在县乡道路改造中的应用 总被引:1,自引:1,他引:1
以山东省陵县丁东路旧路改造为例,介绍了以水泥为外加剂的沥青面层冷再生技术的原理特点以及德工WB525型国产路面冷再生机的推广前景.通过试验研究及施工实践,介绍了沥青面层冷再生技术外加剂剂量的确定方法,为今后中国县乡道路的旧路改造提供可借鉴的施工经验. 相似文献
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