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英语原文共 16 页, 为混合动力汽车建模和仿真开发一个可扩展的、简洁的Simulink工具集 Burak Kanber, Melody baglione 摘要:如今的能源经济把效率看得比什么都重要。作为工程师,我们的工作是发现并消除效率低下的现象,无论大小,无论是对发动机的重大改变还是对班次表进行设计或小的调整。因为对这些效率的需求越来越大, 在混合系统中,系统级设计是关键的一步。汽车开发流程中,有几种工具可以用来模拟混合动力汽车的行为和性能,但其中很多都非常昂贵,对工程师(尤其是学生)来说过于复杂,无法学习,或无法支持自定义或传动系统配置不寻常。 本文将讨论开发一个即简单又可扩展的Simulink工具集来对混合动力汽车系统建模和控制。前瞻性建模方法的选择不仅考虑了控制优化的可能性,而且还提供了可扩展性的便利性
英语原文共 23 页, 混合动力汽车建模与仿真 Ivar Roskifte Leikarnes 摘要:本文综述了混合动力电动汽车的各种结构形式,并对其零部件的选择提出了基本的指导原则。为了研究滚动阻力系数和车辆重量对混合动力汽车燃油效率的影响,本文建立了混合动力汽车的仿真模型。虽然该模型并不是针对发动机的最佳运行而设计的,但结果表明,较低的滚动阻力系数和较低的车辆重量会导致油耗降低。报告中提出了对仿真设计的改进建议。 关键词:混合动力汽车,仿真,Simulink,燃油效率 介绍 1.1.历史 1997年,丰田将混合动力电动汽车的概念推广到普锐斯(Prius)上,虽然它实际上是费迪南德bull;保时捷(Ferdinand Porsche)在1900年发明的,但这似乎是一项新发明[1]。Lohner保时捷Semper Vivus是纯电动版Lohner保时捷的升级版,配备了两个
英语原文共 18 页, Nd:YAG激光焊接钢/铝异种合金界面组织演变及相变 1前言 我们发现,在许多工业应用中,如车辆、飞机和航天器中,人们越来越关注轻量化以实现节能减排[1]。在各种轻量化方法中,铝钢混合结构以其减轻车身重量、保证车辆行驶平顺性而备受关注。然而,由于铝合金与钢在热物理性能上的差异,以及有害的Fe-Al金属间化合物(IMCs)的快速形成,铝合金与钢的连接相当困难[2]。IMCs倾向于显著降低接头的延展性,增加开裂敏感性[3],从而影响某些在用产品的安全性。因此,在钢与铝合金的连接方面,人们做了大量的工作,如冷金属转移焊[4]、搅拌摩擦焊[5]、MIG电弧钎焊熔焊[6]和爆炸焊接[7]。由于热源难以精确控制,在焊接过程中会在界面产生大量的金属间化合物。 随着激光输出功率和光束质量的提高,特别
英语原文共 5 页, 基于ELM的MSR和HOG的车牌识别 摘要-本文在极限学习机(ELM)的基础上,提出了一种有效的自动车牌识别方法(ALPT)。首先,应用形态学Top Hat滤波算子对图像进行预处理,然后通过最大稳定极值区域(MSER)检测器提取候选字符区域。第三,根据标准车牌中字符的几何关系,去除了大部分噪声字符区域。最后,从检测到的每个模块的每个字符中提取方向梯度直方图(HOG)的特征,并通过用ELM训练的分类器识别这些字符。实验评价表明,我们的方法在ALPR系统中表现良好。 关键词—车牌识别;极限学习机(ELM);最大稳定极值区域(MSER);方向梯度直方图(HOG) Ⅰ介绍 在过去的几年中,智能交通系统(ITSs)对人们的生活产生了广泛的影响。随着计算机视觉和模式识别的快速发展,越来越多的基于视觉的技术被应
英语原文共 31 页, 1 属性数据 历史上,流体的热力学和输运性质数据是以表格和图形的形式提供的。在与使用表格或图形特性信息相关的限制变得明显之前,您不必解决许多工程问题。在表中查找属性值通常需要单次或双次插值。这个过程很耗时,而且可能会引入数学错误。图形属性数据不需要插值,但是使用这些图是很繁琐的,而且数据的精度是有限的。使用表格或图形特性信息进行优化或设计所需的参数研究是不容易的,甚至是不实际的。 EES为许多物质提供了高精度的热力学和输运热物性数据。使用本章中介绍的内置属性函数访问这些数据。这些特性函数与方程求解和绘图功能相结合,使EES成为需要特性数据的工程计算的有用工具。 1.1单位制 有必要指定EES将用于热力学和输运性质函数的单元系统。
英语原文共 22 页, 英语译文共 20 页, 资料编号:[237247],资料为PDF文档或Word文档,PDF文档可免费转换为Word
英语原文共 6 页, 英语译文共 14 页, 资料编号:[237253],资料为PDF文档或Word文档,PDF文档可免费转换为Word
外文文献翻译 外文原文:第一部分 THE BRAKE BIBLE Brakes - what do they do? The simple answer: they slow you down. The complex answer: brakes are designed to slow down your vehicle but probably not by the means that you think. The common misconception is that brakes squeeze against a drum or disc, and the pressure of the squeezing action is what slows you down. This in fact is only part of the equation. Brakes are essentially a mechanism to change energy types. When youre travelling at speed, your vehicle has kinetic energy. When you apply the brakes, the pads or shoes that press against the brake drum or rotor convert that energy into thermal energy via friction. The cooling of the brakes dissipates the heat and the vehicle slows down. Its the First Law of Thermodynamics, sometimes known as the law of conservation of energy. This states that energy cannot be created nor destroyed, it can only be converted from one form to another. In the case of brake
Int J Adv Manuf Technol (2001) 17:453–461 2001 Springer-Verlag London Limited Three-Dimensional Kernel Development for Injection Mould Design T. L. Neo and K. S. Lee Department of Mechanical and Production Engineering, National University of Singapore, Singapore Today, many software “plug-ins” have been developed on high-level 3D modelling platforms to facilitate processes such as FEM analysis, CAM, injection mould design, simulation and visualisation. Such an arrangement is advantageous in many ways. However, it is not without shortcomings. Ideally, these “plug-ins” could also be developed using low-level 3D kernels for higher flexibility and better portability. This paper examines the various issues and methodologies related to the development of such 3D-based applications. The emphasis is placed on the software aspect. First, a methodology for the development of 3D-based applications is proposed. The idea is then implemented by developing an injection
Compression Loads in Twin Screw Compressors The compression mechanism in a twin screw compressor consists of two helical rotors. In this work, a method is presented for computing the forces and moments induced on each rotor due to gas compression. These are defined as the compression loads. The helical rotor surfaces are defined by the end profiles, wrap angle and rotor length. The 3D surface of each rotor is mapped to 2D integration regions. These regions correspond to the surfaces associated with individual compression chambers. The compression loads are computed by integrating the chamber pressure over the rotor surfaces. The integrals are evaluated at incremental values of the rotor angular position. The method is presented and implemented for a specific compressor configuration. The compression loads are resolved to forces at the bearing locations. These bearing forces are presented for operating pressures which represent an under-pressure condition. A frequency a
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