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971.
CTCS-2-200C列车运行控制设备数据分析和维护 总被引:1,自引:1,他引:0
ATP的维护是确保列车运行的基础.为了列车正常的运行,必须通过对列车运行数据,主要是故障数据.SAM和.MID文件的分析,找出列控设备故障,完善设备. 相似文献
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对船舶轴系非对中时中间轴承振动问题,通过数值模拟和物理模拟进行了研究。前者给出了非线性刚度的轴承振动数学模型和考虑油膜影响的轴段运动数学模型,并得出了稳态数值解;后者按照动力相似原则在柔性转子实验台上搭建了模拟轴系,通过试验考察了轴系具有非对中状态时的中间轴承振动情况。 相似文献
976.
针对薄板分段车间的焊接装备复杂化程度高、焊接作业监控困难、焊接信息反馈不及时等问题,研究薄板分段车间T型梁焊接机器人的工艺流程和工艺参数,开发一种基于对象链接与嵌入过程控制的统一架构[OLE(Object Linking and Embedding)for Process Control Unified Architecture,OPC UA]技术的T型梁焊接机器人在线监测系统。该系统主要对T型梁焊接机器人的生产进度、设备运行状态和中间产品质量等进行在线监测,实现数据实时采集和生产过程监控与分析等功能,可消除设备之间的信息孤岛现象,实现车间生产透明化,提高生产效率,确保焊接质量。 相似文献
977.
This paper presents a practical procedure for creating finite element (FE) model for vibration analysis of cruise ships. The most preferable FE modelling approaches are studied and discussed through case studies of common ship structures, which cover the range from low to high frequencies. The application of homogenized equivalent single layer (ESL) theory based equivalent element for stiffened panel is extended to local forced vibration analysis, where inertia induced interaction between plate and stiffener occurs. Modal method is used with an energy-based correction for accounting the plate-stiffener interaction into modal properties. Case study results reveal that mesh density of one 4-node element per web frame spacing is suitable for global FE-model when vibration analysis is limited to global hull girder modes. For such modes it is sufficient to only include the membrane stiffness of stiffened panels. For investigating the response at higher frequencies, bending properties of stiffened panel should be included and mesh density should be at least two elements per web frame spacing. Then forced vibration analysis can be performed with an excellent accuracy up to frequencies about one third of the local plate natural frequencies between the stiffeners. Beyond that, the influence of the local plate vibration becomes more significant in panel vibration, making the ESL-theory based element limited. With the applied correction method, the validity of the ESL-model can be extended to approximately two thirds of the local plate natural frequency. 相似文献
978.
In addition to the traditional hollow circular sections used in marine structures, other hollow sections have attracted the attention of architects and design engineers due to their mechanical characteristics such as torsional rigidity and local strength against impact loading. The purpose of this study is to investigate dynamic response of pipes conveying fluid with variable wall thickness through both circumferential and axial directions. Pipes with variable wall thickness have different flexural rigidities about two different principal axes. This property allows these pipes to be oriented efficiently, meet various design requirements and resist the applied loads. The results of this investigation provide a better insight into the physics and dynamic behavior of non-circular pipes conveying fluid. Two different geometries are studied, (i) the pipe is assumed with a general non-circular cross section with variable wall thickness along the circumferential direction, (ii) both inner and outer boundaries of the pipe cross section are assumed to be circles whereas the wall thickness of the pipe along axial direction is varied with a specified function. The governing differential equations of the problem are derived using Timoshenko beam theory with the effect of shear deformation included in the formulation. The discretization of the problem domain is done using the finite element method. Consequently, a modal analysis is employed to calculate the critical flow velocities of the pipe with clamped-clamped end conditions. The effects of different cross sections on the critical flow velocity are investigated. The importance of Coriolis forces on the presence of coupled-mode flutter and re-stabilization point are also discussed for different values of mass ratio. 相似文献
979.
目前铁路调度工作质量评价及辅助决策手段自动化、智能化程度相对滞后,日班计划兑现率较低,制约了调度指挥效益的进一步提升。为提升调度工作质量,提高日班计划、阶段计划一体化编制水平,在阐述铁路调度工作质量评价及辅助决策系统目标的基础上,从表示层、业务逻辑层、数据层3个方面对系统进行总体架构,分析铁路调度工作质量评价及辅助决策系统功能,即:以实现基于全局视野的安全过程卡控,基于大数据架构的调度工作质量评价,跨区段、面向岗位的列车运行图辅助盯控及预测,施工组织可视化管控,面向生产决策的一体化数据统计分析,以提升调度整体工作质量与管理水平。 相似文献
980.