柴油发动机的最新排放控制技术

应用了电子学最新发展成果的新型柴油发动机和柴油燃料将会颠覆你以前对柴油车的所有偏见。不仅如此,它还将为汽车维修行业提供新的赢利机会。     

先进的发动机气门电子控制技术

<正>本文译自美国MOTOR杂志。当我们期待着实用化的车用动力装置取代传统的汽油内燃机之时,汽车工程师们也仍在继续努力探索提高传统汽车发动机性能的方法。菲亚特公司的多气门电子控制系统算得上是最新成果的实例。     

北美铁路货车转向架的发展(续一)

9 一系悬挂转向架 一系悬挂转向架也叫做轴箱弹簧转向架，通常是作为提供给特种运用服务的优质转向架。在这种型式转向架上，其主弹簧和阻尼是装在轮轴系统与转向架构架之间的，因而垂向和横向弹簧挠度和阻尼与最小的簧下重量一起就直接作用于转向架轮对运动。随之带来优良的垂向和横向运行品质，以及高速蛇行稳定性和良好的曲线通过性能。 提供的这种基本结构是在运用于欧洲的转向架系列结构基础上设计的，在最新专门设计中，还结合了摆吊式横动和迫导向功能。图18为一种迫导向径向转向架。     

车载多路传输网络的结构特点与协议

在我们开始了解数据网络的结构和协议时,是躲不过总线网络的,因为下一代网络可能就是快速传递数据的时代。     

水平连铸QCr0.5铜合金线电磨损性能研究

对水平连铸工艺制备的QCr0.5铬青铜合金接触导线坯料经过固溶、时效、冷轧处理后,研究接触导线的微观摩擦性能与受流滑动磨损行为,分析不同电流作用下接触导线的磨损形貌及磨损特征。微观划擦测试表明:通过加入合金元素Cr,改变了接触导线合金材料的微观组织,提高了合金材料的强度、抗软化性能和抗变形能力,改善了合金的磨损性能,降低了摩擦系数;水平连铸QCr0.5铬青铜合金接触导线的硬度为165.5HV,最大摩擦系数为0.155,最大压入深度为2.68μm。电磨损测试表明:水平连铸QCr0.5铬青铜合金接触导线未加载电流时的磨损主要以磨粒磨损和黏着磨损为主,载流条件下的磨损主要是黏着磨损、磨粒磨损和电侵蚀磨损。磨损率测试结果显示,水平连铸QCr0.5铬青铜合金接触导线磨损性能明显优于商用Cu-Ag接触导线。     

燃油经济性的解决方案? 汽油直接喷射

本文译自美国《MOTOR》杂志,作者深入浅出地全面讲解汽油直接喷射技术,生动地对这一技术产生的背景、结构原理、主要组成部件以及未来发展趋势进行了系统的阐述。     

车用[42V]电气系统

尽管没有人怀疑42V电气系统的合理性,但是在实施这一标准之前仍然有许多问题必须解决。     

未来发动机中的电子技术

一种功率更大、尾气排放更少和燃油经济性更佳的发动机即将问世,而这种发动机与现在的发动机相比不仅在内部结构上进行了改进,尤其在电子技术方面有了更大的提局。     

Assessment and Promotion of the Great Barrier Reef's Human Dimensions Through Collaboration

Increasingly, natural resource managers see the marine protected areas that they are responsible for as linked social-ecological systems. This requires an equal focus on managing for both natural and human dimensions of the protected estate. Consequently, identification of indicators that represent the human dimensions of Large Scale Marine Protected Areas (LSMPAs) such as the Great Barrier Reef (GBR) is critical if these values are to be properly considered as part of standard management practice. Assessment and monitoring of the human dimensions of LSMPAs requires a replicable, collaborative process, rolled out at local scales but comparable across vast, socially and geographically diverse areas. This paper explores the application of a process for the development, assessment, and monitoring of the GBR's human dimensions. The process includes (a) development of a conceptual framework that links indicator sets to the desired state of the GBR's human dimensions; and (b) a collaborative approach including ten practical steps to implement assessment, monitoring, and benchmarking of the human dimensions of an LSMPA. We conclude with examination of challenges and opportunities for implementing this process in the GBR context, specifically with respect to the targets and objectives of the Reef 2050 Long-Term Sustainability Plan.     

Ride Vibration Measurements of Agricultural Tractor and Trailer Combinations

Tractor ride vibration levels have been measured when operating with and without a two wheel (2W) unbalanced and a four wheel (4W) balanced trailer. Measurements were made in the vertical, pitch, longitudinal and roll directions with the trailers unladen and laden over four typical farm surfaces

The results showed that tractor ride vibration levels were usually increased in all directions-particularly the longitudinal direction- when operating with the laden trailers. But for the unladen trailers, they were increased only in the longitudinal direction. Predominant tractor frequencies tended to be lower with the trailers attached, and coupling between the tractor longitudinal, vertical, roll and pitch co-ordinates was generally increased

Comparisons of the results with the trends predicted by a simplified theoretical model of a tractor and 2W trailer, suggested that the model should be extended to include, (a) the roll direction, (b) more realistic ground inputs, and (c) a 4W trailer