排序方式: 共有21条查询结果,搜索用时 46 毫秒
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汽车前照灯配光性能测试方法的研究 总被引:3,自引:0,他引:3
着重阐述了前照灯近光配光性能测试中的各测试点及区域的含义、测试方法以及误差分析。提出了提高测试速度和精度的方法,还介绍了国家汽车质量监督检查中心研制的激光灯具全自动照准仪和计算机多功能配光自动测试软件及其应用。 相似文献
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Different weight thresholds for drone operations have been specified by regulatory agencies in different countries, without detailed backgrounds of guidelines. Therefore, this paper aims to study weight thresholds by focusing different levels of injuries caused by the impact of the drones on human head of different weights dropped at various heights. The work covers drone free drop modelling, FEM (finite element method) based impact modeling, and comparable drop impact experiments. The analyses and experiments were conducted accordingly to two individual commercially-available groups: small and large drones in weights. Two well-established indicators defining head injuries due to impact, which are known as Head Injury Criterion (HIC) and Abbreviated Injury Scale (AIS), are used in the present weight threshold study. The proposed AIS level for the weight threshold estimation has been set at AIS level 3, which indicates major skull fracture, in the further analysis through the probability of fatality. The main focus of the present work is to perform a parametric study and to present a reliable model to estimate the weight thresholds of the drone operations based on HIC and AIS. In conclusion, the results obtained and presented in this paper have demonstrated and provided a comprehensive analysis of possible direct injuries of a falling drone impacting a human head, with relevant data of impact or injury levels associated with HIC and AIS obtained for a drone with different weights falling from various heights. 相似文献
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根据航海日志及碰撞事故报告中可能提供的船舶运动过程等资料及其精度,建立各参数物理意义鲜明、并可从船舶资料中直接或间接获取的船舶运动数学模型,利用计算机,直观显示或绘制船舶运动轨迹,供有关人员分析和处理碰撞海事参考。 相似文献
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Vertical bending moment (VBM) is of crucial importance in ensuring the survival of vessels in rough seas. With regard to conventional vessels, wave-induced maximum VBM is normally considered to be experienced in head seas. It is conservative to determine the extreme VBM based on either numerical simulations or model tests in long-crested head seas. Extensive model tests have been conducted in head seas with focus on the nonlinear vertical responses in severe seas, and the measured results were compared with numerical calculations for validation. Unexpected phenomena, however, were observed during the model tests of an ultra-large containership. The maximum sagging and hogging VBMs were encountered in oblique seas. Furthermore, the significant wave height used in oblique seas was even smaller than that used in head seas. The nonlinear vertical load effects in oblique seas require further investigations for this particular vessel. Limited experimental results in oblique seas have been reported, in which the lateral responses were always more concerned than the vertical responses. Up to now, rare systematic comparisons of the nonlinear vertical responses between head and oblique seas have been published, especially when the hydroelastic effects are also accounted for. A 13000-TEU ultra-large containership model, which was designed by Hyundai Heavy Industries (HHI), has been tested in the towing tank and the ocean basin at the Marintek center in Trondheim. The experimental results in regular waves are first compared between head and oblique seas. The statistical characteristics of the VBM amidships under nineteen irregular wave conditions are then investigated. Next, the extreme hogging and sagging VBMs are compared under different wave conditions with focus on the extreme hogging VBMs. At the end of the paper, the uncertainties in the experiments are discussed. 相似文献
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随着汽车被动安全的发展,对于儿童乘员的保护日益受到重视。C-NCAP2012版中,要求在正面碰撞试验后排放置P3儿童假人.用于评价儿童约束系统。文章按照要求首先对比了各国法规中儿童假人的伤害评价方法,通过对不同车型试验数据的研究,讨论后排儿童假人伤害情况。并根据不同的因素,尤其是儿童安全座椅形式,对结果的影响进行分析。结果表明,上拉带式座椅保护效果最好;坐姿较直时对胸部伤害较小,但对头部伤害较大。该研究对于儿童假人的被动安全研究具有很强的实际意义。 相似文献
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前照灯分为可拆式、半封闭式和封闭式3种。其中封闭式前照灯(即真空灯)其反射镜和前透镜是用玻璃制成一体,形成灯泡,内部充以惰性气体,灯丝焊在反射镜底座上。封闭式前照灯的优点是,可避免反射镜被污染及遭受大气的影响。其缺点是,当灯丝烧坏后,需要更换整个总成。1前照灯的使用要点 汽车前照灯应保证夜间行车时有明亮而均匀的照明,使驾驶员能辨明车前100 m左右道路上的任何障碍物;还应具有防眩目装置,以免夜间两车交会时使对方驾驶员目眩而发生事故。前照灯的使用要点有: a.应保持前照灯有良好的密封性,以防灰尘和潮… 相似文献
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