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城市道路下修建地铁车站等地下工程,需考虑施工对既有地面交通的影响,本文基于课题及实例应用研究,介绍了一种新型临时路面体系,并就其设计及应用进行了相关探讨。该种临时路面体系的应用推广对解决目前城市道路开挖施工对交通影响的问题具有重大的现实意义。 相似文献
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Based on Wiener process model, a new approach for reliability evaluation of cross-linked polyethylene(XLPE) is proposed to improve the lifetime evaluation reliability of XLPE under multi-stressing conditions and study the failure probability distribution. In this paper, two accelerated aging tests are carried out under combined thermal and vibration conditions. The volume resistance degradation data of XLPE samples are tested with a24 h interval under the accelerated stressing conditions at(130℃, 12 m/s~2) and(150℃, 8.5 m/s~2), respectively.Nonlinear degradation data obtained from the experiment are transformed to linear intermediate-variable values using time scaling function, and then linearized degradation data are calculated and evaluated on the basis of linear Wiener process model. Considering traditional Arrhenius equation and inverse power criterion, parameters of the linear Wiener model are estimated according to the maximum likelihood function. The relationship curves on probability density and reliability are given, and the lifetime distribution of XLPE under different stressing conditions is also obtained for evaluating the reliability of XLPE insulation. Finally, the life expectancy of XLPE is 17.9 a under an allowance temperature of 90℃ and an actual vibration acceleration of 0.5 m/s~2. The approach and results in this paper may be used for reliability assessment of high-voltage multiple samples or apparatuses. 相似文献
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现场总线在地铁监控系统中的应用及设计 总被引:1,自引:1,他引:0
通过对地铁机电设备监控系统特点的分析,分层次探讨广州已建线路现场总线的应用设计。提出设计要点,同时对现场总线系统在地铁中的发展前景进行展望。 相似文献
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针对传统路端车辆目标检测算法参数多、检测速度较慢等问题,提出了基于YOLOv5 的车辆目标检测算法轻量化改进。首先,选用轻量化 EfficientnetV2 卷积神经网络对原骨干网络进行重构,同时在网络中引入 GAM 注意力机制;其次,为平衡 CIoU 损失和 IoU 损失在损失函数中的权重,引入 α-CIoU 损失代替原有的 CIoU 损失;最后,使用 soft-NMS 算法替换原有的 NMS 非极大值抑制算法。结果表明:相比原算法,改进后算法的精度提升了.51%,检测速度提升了 8.6%,模型大小降低了 31.7%;改进后的模型在提升检测速度的同时,还提高了路端车辆目标的检测性能。 相似文献
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