战车热特性与R744空调系统

分析了某型战车的热特性及对空调系统的特殊要求，介绍了作者所研制的R744空调系统原理样机及初步实验结果。     

R22热力性质的简易计算公式

建立数学模型要用到许多计算公式，而一些计算公式非常繁杂，不适于建模时采用。可用MATLAB拟合一组R22热力性质的简易计算公式，当已知压力或温度计算其它热力性质参数时无需任何迭代运算。这些计算公式分别是压缩性系数Z与压力P的计算公式，单位容积制冷量qw与蒸发温度、冷凝温度的计算公式以及比容v与温度te的计算公式。通过实际运行，在常用的温度和压力范围内，有较高的计算精度，能满足工程的实际应用。     

汽车企业RD数据质量的提升方法

提高科技统计数据的质量,就要保证R＆D数据的准确性、及时性、完整性和适用性.R＆D数据质量的准确度,直接影响着科技统计工作的成效,对科技决策和科技创新有着不可估量的影响.文章归纳了影响R＆D数据质量的因素,针对汽车企业R＆D数据采集现状及存在的问题,提出提高科技统计数据质量的途径,并举例说明判断数据属性的概念,同时阐述了数据折算的方法和理论依据.     

欧洲ECE汽车技术法规有关客车标准的动态研究

根据欧洲ECE汽车技术法规修订情况,对欧洲ECE客车相关技术法规动态变化进行整理分析,并介绍目前欧洲ECE汽车技术法规在我国客车标准中的具体应用,可为掌握国际汽车技术法规现状和发展趋势以及我国客车标准体系的不断完善提供重要依据.     

Increasing urban tram system efficiency,with battery storage and electric vehicle charging

This paper examines the possible placement of Energy Storage Systems (ESS) on an urban tram system for the purpose of exploring potential increases in operating efficiency through the examination of different locations for battery energy storage. Further, the paper suggests the utilisation of Electric Vehicle (EV) batteries at existing Park and Ride (P&R) sites as a means of achieving additional energy storage at these locations. The study achieves this through MATLAB modelling utilising captured GPS data and publically available information. This study examines the scenario of uni-directional substations with no interconnection between the overhead catenary for both directions of travel, and discusses the trade-offs between ESS size and required current limits.The results show the savings in both energy and basic CO₂ emissions alongside the discussion of Return on Investment (RoI) that can be achieved through the potential installation of ESS at identified ideal locations along the tram network. Moreover, this may be extended to the use of EVs as stationary ESS sited at the existing P&R facilities. Further, the model may also be used to inform future infrastructure upgrades and potential improvements to air quality within urban environments.     

预制钢筋混凝土结构在地震荷载下的往复荷载分析

为了研究预制钢筋混凝土工业结构的地震响应,根据欧洲研究课题组在最新的试验研究中所用的试验原型,建立了SAP2000模型来模拟试验过程.数值模拟将主要研究该结构在不同的地震强度下的往复荷载.数值分析表明,文中的分析模型和方法可以再现试验过程,具有较高的仿真精度,为SAP模型用于分析结构的地震响应提供了依据.     

ECE R58后下部防护认证装置统一规定的解读

为防止行驶中小车追尾大货车的情况发生,欧洲经济委员会对此做出了相关法律规定,即ECER58《后下部防护认证装置统一规定》。文章介绍了ECER58法规的内容和要求,描述了与此法规相关的加载试验内容和试验步骤,联系实际,对如何确保设计符合试验要求进行了相关说明。试验结果符合认证要求,为汽车后防护的设计安装和相关试验提供了参考。     

Bottleneck congestion pricing and modal split: Redistribution of toll revenue

The paper examines the question of the redistribution of toll revenue as seen in a bottleneck congestion model. Our objective is to analyse the impact of this redistribution on total cost and on modal split between railroad and road. Following Tabuchi’s two-mode model (Tabuchi, T., 1993. Bottleneck congestion and modal split. Journal of Urban Economics 34, 414-431.), we integrate a redistribution of toll revenue towards public transport into our study. In this context, we investigate two kinds of road toll regimes: a fine toll and a uniform toll. We will consider two types of railroad fare: when it is set equal to the marginal cost and when it is set equal to average cost. These models allow us to show that toll policy to be more efficient as long as toll revenue is directed towards public transport when the railroad fare is equal to average cost.     

汽车覆盖件试模调整问题

介绍了汽车覆盖件试模调整工艺和试模调整钳工与CAE/CAD/CAM/CAT的关系,以及高速雕刻机与压力机的精度及提高高速雕刻机加工精度的方法。对汽车覆盖件拉伸模、修边模(含冲孔)及翻边模(折边)等在试模调整工艺中出现的冲压件R角不良、回弹及翻边(折边)尺寸超差等问题,以及冲压生产操作性不良的情况进行了分析。指出了上述工艺问题的原因及现场整改需要调整钳工的直觉与现场试验来解决。