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Mechanical model and vibration equation of a cable in cable-stayed sparse latticed structure (CSLS) under external axial excitation were founded. Determination of the mass lumps and natural frequencies supplied by the space latticed structure (SLS) was analyzed. Multiple scales method (MSM) was introduced to analyze the characteristics of cable's parametric vibration, and the precise time-integration method (PTIM) was used to solve vibration equation. The vibration behavior of a cable is closely relative to the frequency ratio of the cable and SLS. The cable's parametric vibration caused by the external axial excitation easily occurs if the frequency ratio of the cable and SLS is in a certain range, and the cable's vibration amplitude varies greatly even if the initial disturbance supplied by SLS changes a little. Furthermore, the mechanical model and vibration equation of the composite cable system consisting of main cables and assistant cables were studied. The parametric analysis such as the pre-tension level and arrangement of the assistant cables was carried out. Due to the assistant cables, the single-cable vibration mode can be transferred to the global vibration mode, and the stiffness and damping of the cable system are enhanced. The natural frequencies of the composite cable system with the curve line arrangement of assistant cables are higher than those with the straight-line arrangement and the former is more effective than the latter on the cable's vibration suppression. 相似文献
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正一路青峰隐隐,两岸亭台楼阁。韩江轻舟横渡,满池碧绿烟波。从东山一路向西,全长64公里的潮漳高速,带你一路驰骋,跨越地域界限,领略大美河山。广东省东山(闽粤界)至潮州古巷公路(简称"潮漳高速")于2017年12月28日正式通车,连接着福建、潮州两大文化古城精神脉络的潮漳高速,架起了时光穿梭的文化桥梁。风情土楼、青岚地质园、湘子桥、凤凰塔、牌坊街……潮州城外,横卧韩江之上的潮漳高速,像一把悠扬的古琴,日夜传唱别样潮州的建造技巧之奇与秀美山川之趣。 相似文献
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柳杰 《现代城市轨道交通》2011,(4):40-42
无线车载台是专网无线集群系统的重要组成部分和高频使用终端,用于实现司机与控制中心调度、车站人员之间的通信,为车辆调度作业提供高效可靠的无线语音及数据服务控制。简单介绍南京地铁2号线无线车载台的硬件组成,重点阐述无线车载台的日常维护、检修模式、检修周期以及常见故障排查。 相似文献
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Wind Vibration Study of Long-span Steel Arch Structure of Beijing Capital International Airport 总被引：4，自引：0，他引：4
IntroductionThe long-span light-weight steel arch struc-tures have been widely used in the world due to itsbeautiful shape and reasonable mechanical charac-teristics. With the development of the computa-tional theory, the steel arch span becomes longerand longer. So, the wind loads become the majoror even dominant loads applied on steel arch struc-tural system[1~3]. The distress and damage willprobably occur in the structure, because of thelong term wind-induced vibration.1 Structural Wind-in… 相似文献
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Introduction For decades, the long-span space structurehave been widely used in the world. The light steearch structural system also becomes popular, because of its beautiful shape, reasonable structurand low cost[1]. With the application of higstrength structural steel and advanced constructiotechniques, however, the flange plates and web oa steel arch system have become thinner and thinner than before, which makes the structural stability more serious, especially for the long-span thiwall va… 相似文献
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传统的夜间车辆检测基于车灯特征的提取和识别,这类方法容易发生误判、检测精度和检测实时性不高。针对上述问题,本文研究了基于改进Mask RCNN(mask RCNN-night vehicle detection,Mask RCNN-NVD)的夜间车辆检测算法。将残差网络（residual network,ResNet）结构中的普通卷积修改为数量为16组的分组卷积,通过16组1×1卷积实现通道数叠加,将网络参数降至普通卷积的1/16,提升检测速度,并实现与普通卷积相同的效果;将通道注意力机制模块（squeeze-and-excitation,SE）嵌入ResNet结构中,通过2个全连接层构建瓶颈结构,将归一化权重加权到各通道特征,增强网络表征能力;在特征金字塔网络（feature pyramid networks,FPN）后加入自底向上结构,将底层特征强定位信息传递到高层语义特征中;加入自适应池化层,根据区域候选网络（region proposal network,RPN）产生的候选区域分配至不同尺度特征图中,并在底层特征与各阶段最高层特征之间加入跳跃连接结构,实现缩减模型参数的同时保留... 相似文献
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柳杰 《现代城市轨道交通》2010,(5):21-23
车载视频系统是现代城市轨道交通乘客信息系统的重要组成部分。主要介绍车载视频系统组成及工作方式,重点阐述车载视频系统的日常维护、检修模式、检修周期以及故障排查。 相似文献
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柳杰 《现代城市轨道交通》2018,(4)
位置更新,即自动转组功能,是无线集群通信系统的重要功能之一,它是实现调度指挥权顺利移交的重要手段。自动位置更新功能失败直接影响调度员次日使用信号楼调度台指挥列车出库。以南京地铁2号线无线系统为例,阐述位置更新的意义、原理和流程,并结合其运营,详细介绍导致位置更新失败的主要原因——错误回库。 相似文献
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