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51.
文章所用车身为某车厂开发的一款新型商用车,车身结构为非承载式车身,相较于承载式车身而言,非承载式车身多了底盘大梁架,在遇到碰撞或者冲击时,车架的振动通过弹性单元传到车身,可以削减大部分冲击力,车身的安全性得以保证,在恶劣道路上,可以保证其稳定性和舒适性,车内噪声和振动也较小。车身主要包括了白车身、车门、座椅、中控、内外饰等主要总成。车身主体大部分都是钣金类零部件,文章所述的车身钣金件有624个,文章完成了车身钣金件的网格划分和属性赋予,并对白车身整体进行了网格质量的验证,并完成了车身模态从1阶到6阶的校核,证明了白车身模态的合理性。 相似文献
52.
介绍了丰田凌志400型轿车安全气囊的组成、工作原理、故障代码的读取和清除,以及安全气囊检修的注意事项。 相似文献
53.
In this paper, a proposed car-following driver model taking into account some features of both the compensatory and anticipatory model representing the human pedal operation has been verified by driving simulator experiments with several real drivers. The comparison between computer simulations performed by determined model parameters with the experimental results confirm the correctness of this mathematical driver model and identified model parameters. Then the driver model is joined to a hybrid vehicle dynamics model and the moderate car following maneuver simulations with various driver parameters are conducted to investigate influences of driver parameters on vehicle dynamics response and fuel economy. Finally, major driver parameters involved in the longitudinal control of drivers are clarified. 相似文献
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从国际船舶融资的角度看,缺少船舶融资租赁权登记规定的船舶登记制度,是不利于跨国船舶融资租赁的。我国《船舶登记条例》中有关光船租赁权登记制度的基本精神和具体做法可为船舶融资租赁权登记制度提供有益借鉴。但仍存在一些不足,笔者试着从这方面提出若干建议。 相似文献
57.
利用ADAMS/Car建立起车辆虚拟样机模型,通过试验验证了模型的正确性;在模糊控制方法的基础上,设计出横摆角速度反馈控制器和质心侧偏角反馈模糊控制器,以及两者联合反馈控制的模糊控制器;最后通过ADAMS/Car与MATLAB/Simulink联合仿真对这3种控制器进行研究.为车辆侧倾稳定性控制提供了一种有效的方法. 相似文献
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为分析建成环境对家庭小汽车拥有的影响,考虑交通小区间的空间相关性,分别基于0-1 邻接矩阵、共同边界邻接矩阵及质心空间距离矩阵构建了层次Bayesian 模型,并与不考虑空间相关性的模型结果进行了对比.基于长春居民出行调查数据对模型参数进行估计,结果表明:交通小区间的空间相关性显著存在;以不考虑空间相关性的模型作为对比,基于公共边界邻接矩阵的层次Bayesian 模型拟合效果最优;在控制家庭层面社会经济变量后,居住密度、土地利用混合度、交叉口密度及公共交通站点密度均对家庭小汽车拥有具有显著的负向效应,表明通过优化城市建成环境策略可有效抑制小汽车拥有量的增长. 相似文献
59.
Increased speed variation on urban arterials is associated with reductions in both operational performance and safety. Traffic flow, mean speed, traffic control parameters and geometric design features are known to affect speed variation. An exploratory study of the relationships among these variables could provide a foundation for improving the operational and safety performance of urban arterials, however, such a study has been hampered by problems in measuring speeds. The measurement of speed has traditionally been accomplished using spot speed collection methods such as radar, laser and loop detectors. These methods can cover only limited locations, and consequently are not able to capture speed distributions along an entire network, or even throughout any single road segment. In Shanghai, it is possible to acquire the speed distribution of any roadway segment, over any period of interest, by capturing data from Shanghai’s 50,000+ taxis equipped with Global Positional Systems (GPS). These data, hereafter called Floating Car Data, were used to calculate mean speed and speed variation on 234 road segments from eight urban arterials in downtown Shanghai. Hierarchical models with random variables were developed to account for spatial correlations among segments within each arterial and heterogeneities among arterials. Considering that traffic demand changes throughout the day, AM peak, Noon off-peak, and PM peak hours were studied separately. Results showed that increases in number of lanes and number of access points, the presence of bus stops and increases in mean speed were all associated with increased speed variation, and that increases in traffic volume and traffic signal green times were associated with reduced speed variation. These findings can be used by engineers to minimize speed differences during the road network planning stage and continuing through the traffic management phase. 相似文献
60.
6S现场管理是针对企业生产现场管理的有效方法,符合铁路倡导人本管理的精神。结合铁路货车检修生产实际,指出应用6S现场管理方法的主要内容和关键要点。 相似文献