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在大量的对比试验的基础上介绍了我国现有的车载式平整度检测设备,阐述了与其相关的指标和评定标准,并对其购置和使用提出了方案。 相似文献
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To identify the potential relationship between Pheaocystis globosa bloom conditions and seawater properties, a hydrobiological survey was performed in the inshore waters of the Eastern English Channel over the course of the phytoplankton spring bloom. Chlorophyll concentration, auto- and hetero/mixotrophic composition of protists and standing stock, and seawater viscosity were measured weekly from March to June 2004. The decline of the bloom is characterized by a massive foam formation in the turbulent surf zone. Before foam formation, seawater viscosity significantly increased, showing a significant positive correlation with chlorophyll concentration. In contrast, after foam formation this correlation was negative, seawater viscosity kept increasing despite a sharp decrease in chlorophyll concentrations. No significant correlation has been found between seawater viscosity and the composition of the phytoplankton assemblages observed during the survey. However, significant positive correlations have been found between seawater viscosity and both the size and the abundance of P. globosa colonies. From the correlation patterns observed between chlorophyll concentration and seawater viscosity, we suggest that the rheological properties of seawater are mainly driven by extracellular materials associated with colony formation and maintenance rather than by cell composition and standing stock. 相似文献
54.
Andrew J. Pick David J. Cole 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(9):781-805
The article reports an experimental study of driver steering control behaviour in a lane-change manoeuvre. Eight test subjects were instrumented with electromyography to measure muscle activation and co-contraction. Each subject completed 30 lane-change manoeuvres with one vehicle on a fixed-base driving simulator. For each driver, the steering torque feedback characteristic was changed after every ten manoeuvres; the response of the vehicle to steering angle inputs was not changed. Drivers' control strategies were found to be robust to changes in steering torque feedback. Path-following errors, muscle activity and muscle co-contraction all reduce with the number of lane-changes performed by the driver, suggesting the existence of a learning process. Comparing the test subjects, there was some evidence that high levels of co-contraction were used to allow high-frequency steering inputs to be generated. The results contribute to the understanding of vehicle-driver (and more generally, human-machine) dynamic interaction. 相似文献
55.
HE Tseng J. Asgari D. Hrovat P. van der Jagt A. Cherry S. Neads 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2005,43(3):199-216
In the pursuit of an objective rating on vehicle stability performance, it is always desirable to reduce disturbances and inconsistencies during experimental evaluations, especially the ones introduced by human drivers. This paper presents the development of a steering robot designed for closed-loop steering tasks during evasive manoeuvres. It describes the controller structure and discusses experimental results, in addition to simulation/vehicle model verifications and theoretical control analysis. 相似文献
56.
GSM-R系统可靠性分析与评估 总被引:2,自引:0,他引:2
GSM-R 铁路专用无线通信系统在我国的应用已经起步,其系统可靠性尚待实际营运的考验。本文应用故障模式影响分析法(FMEA)和故障树分析法(FTA)对 GSM-R 系统的可靠性进行了分析和评估, 针对话音业务和数据业务的阻塞问题以及切换与中断问题给出了相应的解决措施,并讨论了提高 GSM-R 系统可靠性设计的相关对策。 相似文献
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以FRP正弦波形夹心桥面板作为研究对象,得到等效正交各项异性实心板,通过理论分析和数值对比,证明了方法的可行性;采用该法对一实际的FRP正弦波形夹心板桥进行了模态分析。 相似文献
60.
王渤洪 《变流技术与电力牵引》2006,(1):46-53
ICE 系列新动车ICE3、ICET、ICE TD采用了层级结构的诊断系统COBRA(Central On Board RailwayAssistant车载辅助中心),有各装置的自诊断和动车有关的上一级诊断.COBRA诊断系统有清晰的目标群取向,总是只向车务人员和维修人员提供重要的信息和可能的补救措施.在列车进段之前就对自动释放和经无线传输的诊断数据做了计算.列车一进段就准备好了维修人员和维修材料,例如更换损坏件和磨耗件,在进行清洁作业的同时为列车下一次运行准备好了良好的状态. 相似文献