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91.
喷涂型聚脲弹性体在地铁车站防水工程中的应用 总被引:1,自引:0,他引:1
喷涂型聚脲弹性体具有优异的物理力学性能及耐老化、固结快、施工方便的特点,在国内外得到非常广泛的应用。简要介绍了喷涂型聚脲弹性体的反应机理和喷涂机理、性能特点;着重叙述了喷涂型聚脲弹性体的喷涂施工工艺和设备以及注意事项。上海轨道交通8号线四平路站、10号线同济大学站防水工程应用喷涂型聚脲弹性体取得了良好的效果。 相似文献
92.
Most routing protocols for sensor networks try to extend network lifetime by minimizing the energy consumption, but have not taken the network reliability into account. An energy-aware, load-balancing and fault-tolerant routing scheme, termed as ELFR was propsed to adapt to the harsh environment. First a network robustness model was presented. Based on this model, the route discovery phase was designed to make the sensors to construct into a hop-leveled network which is mesh structure. A cross-layer design was adopted to measure the transmission delay so as to detect the failed nodes. The routing scheme works with acknowledge (ACK) feedback mechanism to transfer control messages to avoid producing extra control overhead messages. When nodes fail, the new healthy paths will be selected locally without rerouting. Simulation results show that our scheme is much robust, and it achieves better energy efficiency, load balancing and maintains good end-to-end delay. 相似文献
93.
Dongrun Liu Tianpei Cao Dong Chen Yupu Xiong 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(2):173-189
Assessment of the vibration of high-speed trains negotiating complex sections of terrain under strong wind conditions is very important for research into the operation safety and comfort of passengers on high-speed trains. To assess the vibration of high-speed trains negotiating complex sections of terrain under strong wind conditions, we performed a field measurement when the train passes through typical sections of complex terrain along the Lanzhou–Xinjiang high-speed railway in China. We selected the lateral vibration conditions, including the roll angle and lateral displacement of car-body gravity centre through two typical representative sections (embankment–tunnel–embankment and embankment–rectangular transition–cutting) for analysis. The results show that the severe car-swaying phenomenon occurs when the high-speed train moves through the test section, and the car-body lateral vibration characteristic is related significantly to the state of the terrain and topography along the railway. The main causes for this car-swaying phenomenon may be the transitions between different windproof structures, and the greater the scale of the transition region between different windproof structures or landform changes, the more obvious the car-swaying phenomenon becomes. The lateral vibration of the car-body is relatively steady when the train is running through terrain with minor changes in topography, such as the windbreak installed on the bridge and embankment, but the tail car sways more violently than the head car. When the vehicle runs from the windbreak installed on the embankment into the tunnel (or in the opposite direction), the tail car sways more intensely than the head car, and the head car runs relatively stable in the tunnel. 相似文献
94.
通过对别克陆尊发动机不能启动故障的检修,以发散思维分析查找造成故障的深层次原因,以及采取彻底排除故障的有效措施,为同型号车辆的相同故障检修提供指导性经验,亦可作为汽车制造厂家技术改进的依据。 相似文献
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97.
广州地铁4号线箱梁节段预制施工技术 总被引:1,自引:1,他引:0
广州市轨道交通4号线南延段(黄阁至冲尾)(预制4标)工程,对简支梁、连续梁节段箱梁在制梁场采用短线法预制施工。简要介绍短线台座法节段箱梁预制施工主要工艺和方法。 相似文献
98.
西康铁路增建二线太峪滑坡勘察 总被引:2,自引:1,他引:1
太峪滑坡是西康二线控制线路方案的重要工点,在勘察中运用物探、钻探等综合勘探手段,查明了太峪滑坡的特征,进行了滑坡成因分析,评价其稳定性,为地质选线提供了依据。 相似文献
99.
介绍了软交换与无线接入网组网模式的系统结构,然后指出该组网模式下漏号问题产生的原因,进而提出两种不同的解决方案. 相似文献
100.
任务分解是国民经济动员仿真演练系统中重要的一个环节。针对动员活动的目的及其特性,以时间短和经济成本低为目标建立了单产品多企业的生产任务分解模型。基于利率体现时间价值的观点,将时间转化为经济成本,因此原问题转化为单目标的规划问题。最后采用A*算法对转化后的问题求最优解。 相似文献