关键词： 双机械端口电机   混合动力汽车   转矩标定   整车试验  

摘要： 双机械端口电机(DMPM)是一种具有2个机械端口和2个电气端口新型电机。基于该种电机的混合动力汽车能够实现电力无级调速,已成为混合动力汽车研究领域中的一个热点。对永磁性双机械端口电机(PM-DMPM)的能量传递原理进行分析,并应用其对发动机的转矩进行标定,给出标定的试验结果,完成了基于PM-DMPM的混合动力汽车转矩输出特性试验,完成了基于PM-DMPM的混动力汽车的整车试验。试验内容包括停车发电、纯电动行驶、启停发动机、混合动力驱动等完整的车辆行驶工况。整车经过国家交通部试验场的百公里加速和30%标准坡道的试验,达到试验要求。

关键词： 菲亚特   中国工程机械   动力总成   科技   经验积累   依维柯   意大利   发动机   战略调整   变速箱  

摘要： 菲亚特(FIAT)发源于意大利,100多年的发展早已使它的名声远播世界各地。而在中国工程机械市场,"涉世未深"的菲亚特则正处于开发和经验积累阶段。2011年年初,菲亚特集团拆分为菲亚特汽车与菲亚特工业两大板块。其中,工业板块包括凯斯纽荷兰、依维柯和菲亚特动力科技(FPT)。在完成这些重大战略调整之后。

关键词： 故障诊断   隐马尔可夫模型   支持向量机   核动力设备  

摘要： 核动力设备复杂且积累的资料与故障样本少,传统的诊断方法有待改进。隐马尔可夫模型与支持向量机是一种新的智能诊断技术。本文针对核动力设备机械故障诊断的特点,采用隐马尔可夫模型建模的方式进行故障的初步诊断,再利用支持向量机小样本的强推广能力进行进一步甄别。主泵故障模拟装置上的验证实验表明,HMM&SVM混合模型具有较高的故障识别率。

关键词： 机械式变速器   动力学模型   仿真  

摘要： 分析了无动力中断机械式变速器(UST)的核心部件-多模可控换档器(MCS)的工作特性,建立了MCS动态模型和UST传动系统的动力学模型,在Matlab/Simulink软件平台上搭建了UST仿真模型。通过与UST试验平台结果相对比,UST系统动力学模型的正确性得到了验证。UST传动系统的建模与仿真工作为进一步动态换档特性优化奠定了基础。

关键词： 大型运输机   机械操纵系统   动力学建模   飞行品质   性能验证  

摘要： 为提高大型运输机长跨度软式操纵系统(MMFCS)设计时的操纵性能,而得到优化的机械飞行操纵系统,采用软式操纵回路等效刚度的计算方法,引入钢索等效弹性模量的计算公式,得到软式操纵回路的等效刚度计算新方法.用多自由度刚体动力学的方法研究了整个软式操纵系统的建模问题,在一个软件平台上建立了整个操纵系统动力学模型,为操纵系统性能的综合性能仿真和品质评定提供了一种新思路.通过数字仿真结果与机械操纵系统物理实验报告的比较,证明了操纵系统回路刚度计算以及系统操纵性能仿真具有工程设计的参考意义,验证了该方法的有效性.

关键词： 微机械   动力学   尺度效应   纳米机械  

摘要： 介绍了微机械产生的背景、微机械动力学的主要研究内容以及微机械动力学研究的意义。在此基础上,回顾和总结了近年来国内外在多学科耦合大规模动力学模拟、动力学尺度效应分析、纳米机械的动力学模拟等微机械动力学方面的研究进展,并分析了微机械动力学研究不同于宏观机械的方面。最后指出了微机械动力学研究的不足以及有待解决的关键问题。

关键词： 木工机械   电主轴   设计   动力学分析  

摘要： 简要介绍了高速加工的优点和木材高速切削的特点和要求,据此分析了木工机械用高速电主轴的关键技术,然后对木工机械用电主轴进行了结构设计,最后基于传递矩阵法利用MATLAB对所设计的木工机械用高速电主轴进行动力学分析。

关键词： Actin dynamics   Wiskostatin   Dictyostelium discoideum  

摘要： Many essential functions in eukaryotic cells like phagocytosis, division, and motility rely on the dynamical properties of the actin cytoskeleton. A central player in the actin system is the Arp2/3 complex. Its activity is controlled by members of the WASP (Wiskott-Aldrich syndrome protein) family. In this work, we investigated the effect of the carbazole derivative wiskostatin, a recently identified N-WASP inhibitor, on actin-driven processes in motile cells of the social ameba . Drug-treated cells exhibited an altered morphology and strongly reduced pseudopod formation. However, TIRF microscopy images revealed that the overall cortical network structure remained intact. We probed the mechanical stability of wiskostatin-treated cells using a microfluidic device. While the total amount of F-actin in the cells remained constant, their stiffness was strongly reduced. Furthermore, wiskostatin treatment enhanced the resistance to fluid shear stress, while spontaneous motility as well as chemotactic motion in gradients of cAMP were reduced. Our results suggest that wiskostatin affects the mechanical integrity of the actin cortex so that its rigidity is reduced and actin-driven force generation is impaired.

关键词： DYNAMICS   CHAOS theory   MATHEMATICAL models   ENERGY dissipation   PHASE transformations (Physics)   PARAMETER estimation  

摘要： In second part of the paper both classical and novel scenarios of transition from regular to chaotic dynamics of dissipative continuous mechanical systems are studied. A detailed analysis allowed us to detect the already known classical scenarios of transition from periodic to chaotic dynamics, and in particular the Feigenbaum scenario. The Feigenbaum constant was computed for all continuous mechanical objects studied in the first part of the paper. In addition, we illustrate and discuss different and novel scenarios of transition of the analysed systems from regular to chaotic dynamics, and we show that the type of scenario depends essentially on excitation parameters. (C) 2012 Elsevier Ltd. All rights reserved.

关键词： Twinning   Molecular dynamics   Modeling   Dislocation   Plastic deformation  

摘要： An overview is given of the deformation mechanisms in nanotwinned copper, as studied by recent molecular dynamics, dislocation mechanics and crystal plasticity modeling. We highlight the unique role of nanoscale twin lamellae in producing the hard and soft modes of dislocation glide, as well as how the coherent twin boundaries affect slip transfer, dislocation nucleation, twinning and detwinning. These twin boundary-mediated deformation mechanisms have been mechanistically linked to the mechanical properties of strength, ductility, strain hardening, activation volume, rate sensitivity, size-dependent strengthening and softening in nanotwinned metals. Finally, discussions are dedicated to identifying important unresolved issues for future research. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.