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本文在概述轮对空转/滑行保护系统的原理和发展的基础上,提出了城市轨道车辆空转/滑行保护的实施方案,介绍了其组成、特点、原理及系统的电路和程序框图. 相似文献
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本文针对我校轮机管理专业学生专业口语教学中存在的问题,结合自己的授课过程中的体会和所积累的经验,提出了几点行之有效的教学方法,共同仁参考。 相似文献
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Zhi Huang Wentao Nie Shengwei Kou Xiaolin Song 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(12):1864-1882
The major challenges for rollover detection are the accurate modelling of vehicle dynamics and the real-time estimation of the varied parameters. To circumvent the dependence on vehicle parameters, a novel rollover detection method based on the pulsed braking excitation is proposed. With the lateral load transfer ratio (LTR), the relationship between rollover risks and non-driven wheel rotational dynamics is deduced, which is the basis to apply braking excitation on wheels. The lateral acceleration is adopted as the first criterion to activate the rollover detection. Once the pulsed braking is applied to the non-driven wheels, the braking pressure and wheel angular speeds are measured to estimate the LTR on the non-driven axle. In case of emergency, the differential braking-based anti-rollover is implemented. Experiments were conducted on a Hardware-in-Loop bench. The results show that, the pulsed braking can be activated timely, and the LTR on the non-driven axle is estimated accurately. With the anti-rollover control, the roll stability is improved considerably. 相似文献
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We examine lead–lag relationships between new-building and second-hand ship prices. Our analysis shows the existence of a one-directional lead–lag relationship between two ship prices. The direction of lead–lag relationship is not affected by the time evolution and age of second-hand ships, but is affected by the division of shipping sector. Particularly, directions of ship price movements in dry bulk and tanker shipping sectors are opposite. We argue that the opposite directional lead–lag relationships are caused by the difference in competition levels and the difference in the purposes of trading in the two shipping sectors. 相似文献
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本文以交通拥挤问题为研究对象,用微观经济学的方法分析其产生的原因、现有的解决方案,并以上海为例分析了适合我国国情的最优策略之一--"公交优先"系统的经济学意义. 相似文献
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文章分析了高压隔离开关绝缘子的结构特点及材料特性,并使用ANSYS软件对绝缘子进行静力学分析,分析结果表明该绝缘子符合高速动车组技术要求. 相似文献