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关键词： 双离合器自动变速器   换挡模型   控制方法  

摘要： 双离合器自动变速器是目前汽车产业中的一种新型变速器。本文介绍了这种变速器的工作原理,建立了换挡过程的简化模型,找出了自动变速器换挡的关键控制点及控制方法。为保证换挡过程中车辆行驶稳定,就必须对变速器进行有效的控制,以匹配换挡后的输入轴转速。研究表明,双离合器自动变速器应用前景广阔。

关键词： RETROGRADE FLOW   FOCAL ADHESIONS   STRESS FIBERS   NASCENT ADHESIONS   ALPHA-ACTININ   LEADING-EDGE   INTEGRIN ACTIVATION   VINCULIN ACTIVATION   TALIN HEAD   FORCE  

摘要： During cell migration, the forces generated in the actin cytoskeleton are transmitted across transmembrane receptors to the extracellular matrix or other cells through a series of mechanosensitive, regulable protein-protein interactions termed the molecular clutch. In integrin-based focal adhesions, the proteins forming this linkage are organized into a conserved three-dimensional nano-architecture. Here we discuss how the physical interactions between the actin cytoskeleton and focal-adhesion-associated molecules mediate force transmission from the molecular clutch to the extracellular matrix.

关键词： Wet-friction clutch   Extended reset-integrator friction model   SAE#2 test setup   Shudder vibration   Torsional vibration  

摘要： In recent years, there has been a significant increase in the usage of wet-friction clutches. Presently researchers across the globe are involved in improving the performance and lifetime of clutches through testing and simulation. To understand the clutch vibrational and dynamical behavior, an SAE2 test setup mathematical model based on extended reset-integrator friction model is developed in this paper. In order to take into account the different phases of fluid lubrication during engagement cycle, the model includes the experimentally determined Stribeck function. In addition the model considers the viscous effect and the delay in the actuation pressure signal. The model is validated with the experiments performed on the SAE2 test setup in both time and frequency domains. By analyzing the set of experimental results, we confirmed that the amplitude of shudder vibration is independent of the amplitude of applied contact pressure fluctuation. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： PARENTAL CARE  

摘要： The Cuban archipelago hosts at least thirteen endemic species of the genus Eleutherodactylus that live in association with rocks, caves, or limestone landscapes. However, the reproductive biology of Cuban rock-cave dwelling frogs has received little attention. In this contribution, we offer the first report of oviposition, clutch size, nest site locations, and hatching in Eleutherodactylus (Syrrophus) zeus. Clutches of this species in different development stages were sighted in rock depressions and crevices inside of the Gran Caverna de Santo Tomas, located in Sierra de Quemados, Vinales, Pinar del Rio province. Clutch sizes ranged from 48 to 74 eggs, and hatching success was 98% for one of them. Moreover, we document the first report of nest attendance by a species of the subgenus Syrrophus, the strategy of which may be biparental, with either male or female parental care. Our findings are important not only in understanding general life-history strategies, but also in understanding particular strategies for an endemic species whose habitat specialization is associated with an at-risk system.

关键词： 行驶里程   朱先生   离合器   哈尔滨   发动机   变速箱   经历   购车   底盘   单位   长城  

摘要： 车主:哈尔滨 朱先生 座驾:2.0L智悦型 行驶里程:2900公里 购车经历 我就是想买一款大一点的车,当时看了长城哈弗H6、比亚迪S7.但单位里有几位用H6的说2挡不好挂、起步肉,而S7一是提不到车,二是群里有车主说离合器不好,所以都放弃了.后来看了A×7,发动机、变速箱、底盘不错,所以很快定下来了.

关键词： Wet clutch   Friction material   Wear prediction   Thermal degradation   Composite material wear   THERMOELASTIC INSTABILITY   ENGAGEMENT BEHAVIOR  

摘要： A methodology for prediction of wear in the friction lining of a wet clutch subjected to repeated engagement cycles is presented. The wear mechanism is related to both thermal degradation and mechanical effects. The temperature history is obtained by performing a thermohydrodynamic (THD) analysis of the entire engagement process including engagement, soaking, dwelling and stabilization periods. The predictions of the model are in accordance to the experimentally observed "two-stage" wear rate phenomenon recently reported in the literature. (C) 2015 Elsevier B.V. All rights reserved.

关键词： 70E55   93C95   93C42   control   Fuzzy logic   dual clutch   simulation   DCT   DYNAMICS  

摘要： The flow of torque in a twin clutch transmission is investigated and the different phases of torque transfer between the two clutches are studied. In order to prevent torque backlash and intense wear in dry clutch plates, a proper clamp force regulation is used. A full vehicle simulation that includes vehicle and powertrain components is set up. A Fuzzy logic control system is found suitable for clamp force and engine throttle controls. For upshift and downshift cases, the design of controllers for the gearshift process is carried out by defining proper membership functions and Fuzzy rules using Matlab/Simulink(TM) software. The effectiveness of the control system is investigated by simulating two upshift and downshift cases. Results indicate that the control system is successful in regulating the clutch clamp forces and the engine throttle in such a way that a smooth torque flow in the transmission is achieved in all cases.

关键词： 汽车   起步   离合器控制  

摘要： 在汽车起步过程中,离合器接合性能受到的影响是多方面的。文章通过细致地分析,找出了影响离合器接合性能的因素,并从实际出发,探讨了离合器的接合规律。

关键词： 双离合器   变速器   操纵机构   控制单元  

摘要： 双离合器02E变速器是由德国大众公司和Brog Warner公司以及Temic公司联合研究出来的。其中Brog Warner公司生产的是离合器和液压系统,Temic公司负责生产电子系统。它和手动档变速器相比较其实就是将手动档的优势和自动档的优势相结合起来。在保持高效率的情况下实现很高舒适性和运动性。该文主要介绍了双离合器变速器的结构组成和工作原理,详细叙述了02E变速器变速理念,并对变速器的S-运动程序、软件选档杆锁(Shift-Lock)、起动锁/起动控制、软件选档杆锁、LaunchControl-程序、用2档"晃出"车辆以及2档起步能功能作了解释。

关键词： 摩擦式离合器   离合器摩擦片   报警装置   汽车发动机   故障率   坦克装甲   间接经济损失   重负载   余热回收利用   振动冲击  

摘要： 当前在工程车辆、坦克装甲车辆等机械设备中普遍采用的是摩擦式离合器,由于其负载重、振动冲击大、工况恶劣等,离合器摩擦片极易因打滑过热而出现磨损加速、烧结失效的现象。据统计,离合器摩擦片的磨损、打滑、烧结故障占设备总故障率的10%左右,故障率较高且每组摩擦片成本很高,为单位造成了不小的直接或间接经济损失,