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排序方式: 共有123条查询结果,搜索用时 31 毫秒
101.
基于有限元法,采用ABAQUS软件,对某商用轻卡车门系统进行了CAE模态、刚度和强度分析,分析结果显示,车门前二阶模态避开了发动机怠速频率,车门刚度和强度满足设计目标,综合评估该商用轻卡车门力学性能满足要求. 相似文献
102.
This paper aims to evaluate the likely effects of the adoption of Longer Heavier Vehicles (LHVs) from the perspective of logistics service providers (LSPs). The research consists of six case studies and a survey of companies which were involved LHV trials in Germany. Wider introduction of LHVs is being increasingly demanded so that road freight transport can better serve and support modern supply chains whilst achieving the desired eco-efficiency advancements. Available literature on LHVs puts a particular emphasis on five factors that need to be included in the assessment of their impact: energy efficiency, CO2 emissions, costs, safety and infrastructure. The research provides an original and innovative empirical study refining and validating the current conceptual framework for assessing LHVs demonstrating it is a valuable tool and providing evidence that the vast majority of companies participating in our study, regardless of their size, were interested in the adoption of LHVs. However, it should be noted that a key limitation of the research is that by focusing on a single country case, the nature and scale of the findings may not reflect practice in other countries and sectors. There is also a need to examine the long-term sustainability of the improvements made. 相似文献
103.
This paper presents the World-wide harmonized Light duty Test Cycle (WLTC), developed under the Working Party on Pollution and Energy (GRPE) and sponsored by the European Union (with Switzerland) and Japan. India, Korea and USA have also actively contributed. The objective was to design the harmonized driving cycle from “real world” driving data in different regions around the world, combined with suitable weighting factors. To this aim, driving data and traffic statistics of light duty vehicles use were collected and analyzed as basic elements to develop the harmonized cycle. The regional driving data and weighting factors were then combined in order to develop a unified database representing the worldwide light duty vehicle driving behavior. From the unified database, short trips were selected and combined to develop a driving cycle as representative as possible of the unified database. Approximately 765,000 km of data were collected, covering a wide range of vehicle categories, road types and driving conditions. The resulting WLTC is an ensemble of three driving cycles adapted to three vehicle categories with different power-to-mass ratio (PMR). It has been designed as a harmonized cycle for the certification of light duty vehicles around the world and, together with the new harmonized test procedures (WLTP), will serve to check the compliance of vehicle pollutant emissions with respect to the applicable emissions limits and to establish the reference vehicle fuel consumption and CO2 performance. 相似文献
104.
汽车电动助力转向系统的基本功能是利用电机产生助力力矩帮助转向。与传统的转向系统相比该系统结构简单,灵活性大,能较好地满足汽车转向性能的要求;在操纵舒适性、安全性、节能等方面也充分显示了其优越性。本文对汽车电动助力转向系统的结构及其动力特性分析,建立数学模型,设计了一种自适应模糊PD控制系统。并进行了仿真研究。仿真结果表明,基于模糊PD控制的EPS比传统PD控制具有更好的助力特性和抗干扰能力。 相似文献
105.
蓝牙公路车辆无线收费系统是一种先进的收费系统,采用了最新的蓝牙技术,能够极大提高道路通行能力。本文对移动环境下蓝牙链路建立的可行性做了一定的研究,设计实现了系统的硬件与相关软件。通过实验,在收费站与移动车辆问实现了无线双向通信与不停车收费。 相似文献
106.
高职学生外事英语拓展能力的培育 总被引:3,自引:1,他引:2
张刚 《辽宁省交通高等专科学校学报》2008,10(5)
文章根据企业商务外交人才的培养和外事英语教学的实践经验,提出外事英语应以培养学生的商务外事能力为目标。文章分析了目前高职学生的语言缺陷,提出了外事英语运用案例教学模式的主要方向和内容,并给出了高职学生外事英语拓展能力培育过程中成绩考核的建设性意见。 相似文献
107.
2009年车用发动机及活塞市场与汽车市场一样,得到了快速增长。2010年国际国内宏观经济形势对汽车、车用发动机及活塞市场来说十分有利,乘用车市场2010年将保持15%的增速,商用车市场将保持10%的增长,2010年车用发动机活塞市场的总产销量将分别达到1.325亿只和1.3014亿只左右,同比将分别增长18%和16%。 相似文献
108.
随着能源危机和环境恶化,汽车工业的进一步发展受到极大的挑战,发展新能源汽车成为未来汽车工业的发展方向。氢电混合动力车是一种新能源车,其动力系统的性能对汽车的整体性能起着至关重要的作用,为了更好地实现其性能,对其结构布置进行研究很有必要。通过与传统汽车、油电混合动力车以及纯燃料电池车的动力系统进行对比,研究了氢电混合动力车动力系统的组成与特点;并详细研究了动力系统的结构布置及其特点和各自适合的工况条件。通过以上的研究,为后续动力系统结构布置的选择提供了参考,并指出了其未来发展的方向。 相似文献
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