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491.
Hyuck-Kee Lee Seong-Geun Shin Dong-Soo Kwon 《International Journal of Automotive Technology》2017,18(6):1067-1076
Globally, safety has become an increasingly important issue in the automotive industry. In an attempt to reduce traffic fatalities, UNECE launched a new EU Road Safety Program which aims to decrease the number of road deaths by half by 2020. AEB (Autonomous Emergency Braking) is a very effective active safety system intended to reduce fatalities. This study involves the design of a multi-sensor data fusion strategy and decision-making algorithm for AEB pedestrian. Possible collision avoidance scenarios according to the EuroNCAP protocol are analyzed and a robust pedestrian tracking strategy is proposed. The performance of the AEB system is enhanced by using a braking model to predict the collision avoidance time and by designing the system activation zone according to the relative speed and possible distance required to stop for pedestrians. The AEB activation threshold requires careful consideration. The test results confirm the advantages of the proposed algorithm, the performance of which is described in this paper. 相似文献
492.
Seungki Kim Kyungsik Shin Changhee Yoo Kunsoo Huh 《International Journal of Automotive Technology》2017,18(6):1077-1083
Estimation algorithms for road slope angle and vehicle mass are presented for commercial vehicles. It is well known that vehicle weight and road grade significantly affect the longitudinal motion of a commercial vehicle. However, it is very difficult to measure the weight and road slope angle in real time because of lack of sensor technology. In addition, the total weight of a commercial vehicles varies depending on the freight. In this study, the road grade and vehicle mass estimation algorithms are proposed using the RLS (Recursive Least Square) method and only the in-vehicle sensors. The proposed algorithms are verified in experiments using a commercial vehicle under various conditions. 相似文献
493.
Fuxing Yang Leilei Zhao Yuewei Yu Changcheng Zhou 《International Journal of Automotive Technology》2017,18(6):1121-1129
To provide initial design values of seat cushion and chassis suspension damping for wheel-drive electric vehicles (WDEVs), this paper presents an analytical estimation method and a practical damping parameters design method. Firstly, two formulae of the human body vertical acceleration in terms of the power spectrum density (PSD) and the root mean square (RMS) are deduced for WDEVs. Then, the coupling effects of the key vehicle parameters on ride comfort are revealed. Finally, with a practical example, the damping parameters of the cushion and the suspension are initially designed and analyzed. The results show that when every 10.0 kg increases for motor mass, the optimal damping values of the cushion and the suspension should be reduced by about 15.0 Ns/m and 50.0 Ns/m, respectively. However, the RMS acceleration increases 0.017 m/s2 with a decrease of 2.5 % for ride comfort. 相似文献
494.
495.
CRH2型动车组受电弓常见故障的应急处理 总被引:1,自引:0,他引:1
邹生敏 《铁道机车车辆工人》2009,(3)
针对CRH2型动车组受电弓有时发生自动降弓、无法升弓等故障,提出了应急处理办法. 相似文献
496.
对出口委内瑞拉守车副构架加工工艺进行分析,简述鞍加工、组对焊接和整体钻孔几个主要工艺过程,解决了副构架加工工艺难点,并提出了工艺优化的建议。 相似文献
497.
邹建美 《铁道机车车辆工人》2010,(9)
通过分析160 km/h快速货车转向架轴箱的加工工艺,制定了合理的工艺方案,制作必要的工艺装备,有效地解决了轴箱内孔及其余位置尺寸和形位公差要求较高的工艺难题. 相似文献
498.
499.
公路工程实施阶段的定额管理探讨 总被引:1,自引:0,他引:1
随着我国经济体制的发展和变革,由于预算定额不能满足施工生产和施工单位没有建立真正的企业定额等原因,导致公路工程实施阶段出现了计价定额空缺的情况。在分析现有定额管理制度对数据真实性的影响和缺乏统一的清单工料机消耗量标准对定额管理的影响后,提出要采用各种手段充分调动施工、设计、咨询等各单位测定定额的积极性,通过强力推行《公路工程工程量清单计量计价规则》,利用计算机和互联网搭建造价基础数据的管理平台,建立和发布基于《规则》的工程实体性工料机消耗量标准的建议。 相似文献
500.
铁路双线长大隧道破碎岩层冲沟带塌方冒顶处理技术 总被引:1,自引:0,他引:1
结合阎家村隧道塌方冒顶段施工实例,介绍了该隧道位于破碎岩层冲沟带塌方冒顶的原因及相关处理技术,为这类隧道塌方冒顶施工提供有益参考。 相似文献