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421.
A traction control system (TCS) is used to improve the acceleration performance on slippery roads by preventing excessive wheel slip. In this paper, a new traction control system using the integrated control of gear shifting and throttle actuation is developed for vehicles with automatic transmissions. In the design of the slip controller, by means of a differential manifold transformation, a slip control system with nonlinearities and uncertainties is transformed into a linear system, and a sliding mode controller is applied for the purpose of increasing the robustness of the system. Next, to achieve the required driving torque, the optimal throttle and gear position, maps are constructed based on dynamic programming. The simulation results indicate that the present traction control system can improve the acceleration performance of an automatic transmission vehicle for various types of road conditions. 相似文献
422.
GPRS道路实时监测系统直接监测试验车辆的运行状态及车辆的试验数据,系统能否安全稳定运行对试验结果意义重大。因此系统数据传输的安全性是一个至关重要的问题。 相似文献
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Compensation factor method for modeling springback of auto parts constructed with high-strength steel 总被引:1,自引:0,他引:1
X. -K. Zhang G. J. Zheng J. -N. Hu C. G. Li P. Hu 《International Journal of Automotive Technology》2010,11(5):721-727
To more accurately manufacture an auto-body workpiece, a predictive compensation factor method was used to predict the workpiece’s
springback, and the factors influencing springback are introduced. Based on this method, a numerical simulation was produced
to simulate the springback compensation after distortion of the workpiece. After analyzing the simulation results, a compensation
method was introduced to reduce the springback influence on an actual workpiece. Here, we used a fortified B-pillar, which
is a kind of longitudinal stand-frame workpiece, made with a high-strength steel material (TRIP700). The simulation results
indicated that the proposed method is feasible and can be efficiently used for predicting the distortion of springback compensation
of an auto-body workpiece. 相似文献
425.
该文通过对沥青的再生分析和对废旧沥青混合料的评价,分析研究了再生沥青混合料的路用性能随再生剂掺量变化而变化的规律,以及对其性能的影响,通过再生沥青混合料马歇尔试验、车辙试验、低温试验,其结果满足热拌沥青混合料技术标准。 相似文献
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利用轮胎模态参数模型对稳态工况下的轮胎滚动阻力进行模拟.计算了不同胎面阻尼下的滚动阻力,所得结果与实际的趋势相符,数值合理.对不同半径转鼓下轮胎滚动阻力的模拟结果与按ISO 181964推荐的公式计算的结果有良好的一致性.表明了该轮胎模型的合理性. 相似文献
429.
Our understanding of transport mode choice is largely based upon functional attributes, such as travel time, cost or accessibility. It is important, however, to also look at symbolic and affective attributes. Indeed, one of the main differences between mass transit and private car use is strongly symbolic: public transport compels users to confront social diversity. Given a hypothetical choice between those modes, 200 residents of the Parisian region were asked five times to evaluate (measuring usage intention on a six point scale: ?3 meaning never and +3 meaning always, with no neutral point) the attractiveness of bus versus car-based transport, according to relative travel time and bus users’ population type. The results show that the symbolic dimension (the social mix) strongly contributes to the desirability of a transport mode, as does the functional dimension (travel time). 相似文献
430.
上海振华港口机械(集团)股份有限公司(振华,ZPMC)在党的改革开放阳光照耀下,认真执行小平同志关于发展才是硬道理,尊重知识、尊重人才,科学技术是第一生产力等一系列指示精神,在各级领导的支持和关怀下,依靠全体职工,抓住机遇,奋发图强;与强争锋,成绩辉煌。13年来,振华已生产大型岸桥600台, 相似文献