Dynamic Simulation Analysis of the Working Device of a ZL50 Loader

In this study,assuming a certain type of wheel loader as the main objective of the research,the performances of the working device of the loader are investigated on the basis of an in-house code.After creating a three-dimensional model of the working device using Solidworks,this model has been imported into the dynamic simulation software ADAMS,and the simulation problem has been completed by adding the relevant constraints and loadings.The load stress curve relating to the main connecting point of the working device has been obtained in the frame work of this approach and it has been shown that the movement characteristics are compatible with(i.e.,they match)the actual working conditions.The present study may be regarded as a theoretical basis for the design and improvement of the working device of a vast category of wheel loaders.

Rapid Modeling of an Excavator Working Device Based on the Secondary Development of Pro/E

In order to shorten the design cycle of the excavator working device, we have proposed a rapid modeling method for the excavator working device which uses parameters. Based on the Pro/toolkit, which is secondary development tool of Pro/E4.0,and combined with Vs C＋＋2005 programming software. It developed a flexible set of MFC visualization-friendly interfaces. Users can enter data in the visual interface according to their needs and it will generate a new part model quickly. So it improves the design quality, shortens the design cycle, and makes the cost lower significantly.

Review of My Research Work on Ferroelectric Films and Si-Based Device Applications: Opportunity and Challenge

Ferroelectric materials have many interesting physical properties such as ferroelectricity, pyroelectricity, piezoelectricity, and opto-electricity, and applying ferroelectric materials in the forms of thin and thick films and integrating them on the silicon substrate as electronic and MEMS devices is a very attractive research area and challenging. In this paper, we report our research works on ferroelectric MEMS and ferroelectric films for electronic device applications. Pyroelectric thin film infrared sensors have been made, characterized, and a 32×32 array with its size of 1cm×1cm has been obtained on Si membrane. Ferroelectric thin films in amorphous phase have been applied to make silicon based hydrogen gas sensors with the metal/amorphous ferroelectric film/metal device structure, and its turn-on voltage of about 4.5V at ～1000 ppm in air is about 7 times of the best value reported in the literature. For the application of electron emission flat panel display, ferroelectric BST thin films with excess Ti concentrations have been coated on Si tips, the threshold voltage of those ferroelectric film coated tips has been reduced about one order from ～70 V/μm to 4～10 V/μm for different Ti concentrations, and however, the electron emission current density has been increased at least 3～4 order for those coated tips compared to that of the bare Si tips. To fulfill in the thickness gap between thin film of typical ～1 μm made by PVD/CVD and polished ceramic wafer of ～50 μm from the bulk, piezoelectric films with thickness in a range of 1～30 μm have been successfully deposited on Si substrate at a low temperature of 650oC by a novel hybridized deposition technique, and piezoelectric MEMS ultrasonic arrays have been very recently obtained with the sound pressure level up to ～120 dB. More detailed results will be presented and mechanisms will be discussed.

Palm Device在移动医疗信息系统中的应用

为了更好的完成移动办公与移动计算，结合手持设备的特点，本文提出了一种基于手持设备的“离线—在线”综合移动办公解决方案。手持设备是计算机便携化发展的成果，小巧灵活，并且具有一定的计算能力，非常适合应用到移动计算的场合中。由于“离线”方式与“在线”方式相结合，该方案可以很好的解决在移动办公的背景下，进行信息交互的要求，并且可以应用到其它的非医疗的移动信息系统中去。

Right Ventricular Failure Following Left Ventricular Assist Device Implantation

Left ventricular assist device (LVAD) is being used increasingly in recent years for end stage heart failure as a bridge to transplant (BTT) and also as a destination therapy (DT). Patients with end stage heart failure have some degree of elevated pulmonary capillary wedge pressure, causing right ventricular hypertrophy which in due course leads to decreased dilatation of the RV and fall in cardiac output & severe tricuspid regurgitation (TR) presenting with features of RV failure (RVF). Implantation of LVAD improves left heart function at the cost of right ventricular output with an incidence of 25%-30%. RVF may lead to impaired LVAD flow, difficulty in weaning from cardio-pulmonary bypass (CPB), decreased tissue perfusion and multi-organ failure. In this article we comprehended the pathophysiology leading to RVF post LVAD implantation and its preoperative predictors and the various treatment modalities for managing RVF post LVAD implantation.

A Method for Forecasting Credit Risk of Global Device Purchasing

With the development of the Internet and E commerce, enterprises can achieve global device purchasing with a good cost performance. But the credit risk is the key factor in selecting a device provider. Credit risk involves many qualitative and quantitative factors. We construct a multi agent credit rating model system based on CSCW, which organically combines the people's aptitude and the capability of machines. Enterprises can use this credit rating system for forecasting and defeating the credit risk of global device purchasing.

The action mechanism of the work done by the electric field force on moving charges to stimulate the emergence of carrier generation/recombination in a PN junction

It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron current),which was previously misinterpreted as solely a Joule heating effect.We clarify that it is exactly the work done by the electric field force on the moving charges to stimulate the emergence of non-equilibrium carriers,which triggers the novel physical phenomena.As regards to Joule heat,we point out that it should be calculated from Ohm’s law,rather than simply from the product of the current and the electric field.Based on this understanding,we conduct thorough discussion on the role of the electric field force in the process of carrier recombination and carrier generation.The thermal effects of carrier recombination and carrier generation followed are incorporated into the thermal equation of energy.The present study shows that the exothermic effect of carrier recombination leads to a temperature rise at the PN interface,while the endothermic effect of carrier generation causes a temperature reduction at the interface.These two opposite effects cause opposite heat flow directions in the PN junction under forward and backward bias voltages,highlighting the significance of managing device heating phenomena in design considerations.Therefore,this study possesses referential significance for the design and tuning on the performance of piezotronic devices.

基于SolidWorks的油管试压机造型设计

简介了所设计的油(套)管试压机的功能原理、整体结构以及相关参数,并结合试压机的结构特点,详细论述了利用SolidWorks软件对其进行参数化设计的过程,包括零部件和装配体的三维造型设计以及二维工程图的生成。

基于Workbench的装载机工作装置的优化分析

运用Ansys Workbench对装载机的工作装置进行结构分析,绘出工作装置的应力图;运用Design Exploration功能得出工作装置尺寸参数与最大等效应力的关系,并得出最优值。结果表明:在工作装置工作过程中,动臂前端应力是最大的,对动臂前端尺寸参数进行优化设计后,可在不增加动臂质量的前提下最大限度降低最大等效应力。AWE优化分析可以得出最优设计值,为后续工作装置的设计提供快速、有效的方法。

基于ANSYS Workbench的挖掘机式冲击器工作装置模态分析

挖掘机工作装置最初的设计是以铲斗挖掘为主要功能,装上冲击器后其工作状况为冲击振动,需要对工作装置进行动态特性分析。采用Pro/E软件对某型号挖掘机式冲击器进行三维建模,然后利用ANSYS Workbench建立有限元模型。对挖掘机式冲击器工作装置的三种工况进行模态分析,得到工作装置的固有频率和振型,为挖掘机和冲击器的功率匹配提供一定的依据,并为其优化设计提供理论基础。

基于VxWorks的时统卡驱动程序设计

某相控阵天线的主控计算机采用Vx Works实时操作系统,其时统卡用于校准主控计算机的系统时间,以实现不同系统间的同步控制。本文首先讨论了Vx Works下的I/O系统和设备驱动程序、应用程序之间的关系,然后结合时统卡驱动程序的开发实例,对Vx Works下的PCI设备驱动程序的框架进行了概要介绍,并详细介绍了各个模块的具体实现。实验结果表明,该设计正确实现了Vx Works下PCI设备的驱动程序,满足时统卡使用时的功能要求。

基于solidworks的挖掘机工作装置教具设计

挖掘机是工程机械专业学生必须掌握的工程施工机械之一,购买真机应用于教学面临着成本较高、利用率低的问题,所以提出了设计小型挖掘机模型作为教具的构想。以真机为参考建立了挖掘机工作装置模型,并用solidworksmotion对挖掘机的典型挖掘工况进行了仿真,为下一步教具的制造做好准备。

基于ANSYS Workbench的液压挖掘机工作装置有限元分析与结构优化

以某型号液压挖掘机工作装置为研究对象,运用Creo三维设计软件建立工作装置三维数字化模型,并将工作装置4种典型工况的装配体模型导入ANSYS Workbench有限元软件进行静力学求解,获得了4种典型工况下的应力云图。根据各工况的应力分布情况可知,工作装置工况1的最大应力为679.16 MPa,最大应力位于动臂加强板。为了降低该部位的应力,提出2种方案对该部位进行结构优化。优化后结构的静力学分析结果表明,工作装置动臂加强板的最大应力显著降低,远小于材料的许用应力值,极大地提高了工作装置的结构强度和可靠性。

基于ANSYS Workbench的装载机工作装置静力学分析

装载机的重要部件工作装置在装载机的稳定运行中发挥关键作用。运用Pro/E三维绘图软件建立工作装置的三维模型,运用ANSYS Workbench仿真软件对工作装置进行静力学分析,得到了工作装置的各方向应力图、各平面应力图、等效应力图、等效弹性应变图和总变形图,并对结果进行分析,确定了工作装置的薄弱部位和改进方案,使工作装置更加安全、有效地工作。

A Combining Call Admission Control and Power Control Scheme for D2D Communications Underlaying Cellular Networks

As device-to-device(D2D) communications usually reuses the resource of cellular networks, call admission control(CAC) and power control are crucial problems. However in most power control schemes, total data rates or throughput are regarded as optimization criterion. In this paper, a combining call admission control(CAC) and power control scheme under guaranteeing QoS of every user equipment(UE) is proposed. First, a simple CAC scheme is introduced. Then based on the CAC scheme, a combining call admission control and power control scheme is proposed. Next, the performance of the proposed scheme is evaluated. Finally, maximum DUE pair number and average transmitting power is calculated. Simulation results show that D2 D communications with the proposed combining call admission control and power control scheme can effectively improve the maximum DUE pair number under the premise of meeting necessary QoS.

Robot Position Control Using Force Information for Cooperative Work in Remote Robot Systems with Force Feedback

This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface device while observing work of the robot with a video camera. We also investigate the effect of the proposed control by experiment. As cooperative work, we deal with work in which two robots carry an object together. The robot position control using force information finely adjusts the position of the robot arm to reduce the force applied to the object. Thus, the purpose of the control is to avoid large force so that the object is not broken. In our experiment, we make a comparison among the following three cases in order to clarify how to carry out the control effectively. In the first case, the two robots are operated manually by a user with his/her both hands. In the second case, one robot is operated manually by a user, and the other robot is moved automatically under the proposed control. In the last case, the object is carried directly by a human instead of the robot which is operated by the user in the second case. As a result, experimental results demonstrate that the control can help each system operated manually by the user to carry the object smoothly.

长时间工作固体火箭发动机长尾喷管外绝热装置设计

固体火箭发动机长尾喷管周围一般安装有电子仪器,故而对喷管壳体表面温度有严格的限制。对于某长时间工作的发动机,为满足喷管壳体表面温度要求,同时降低消极质量,设计了一种新型双腔外绝热装置,以实现在较小的消极质量下具有较好的绝热性能。对该绝热装置进行了内流场及传热计算分析,而后进行了绝热结构优化及试验验证。结果表明:该双腔外绝热装置可以将长时间工作固体火箭发动机长尾喷管外壁温度从483℃降低至103℃,降低约78.7%;而采用同等材料同等质量的常规外防护装置只能从483℃降低至227℃,降低约53.0%;而要达到相同的防护效果,同等材料常规外防护装置的质量将增加约160%。双腔外绝热装置中段及尾端处温度随时间变化趋势与实测结果吻合较好,有望应用于其他长时间工作发动机。

一种基于火工品技术的数据安全保护方法研究

数据存储器作为飞行器参数的重要记录设备,在推动远程精确打击武器的发展进程中有重要作用。由于远程武器的射程范围广,常常导致数据存储器无法快速有效地定位回收,若数据存储器被敌人获取,将会导致数据泄露,危害国家安全。基于以上研发背景,分析了各种数据销毁方式的优缺点,设计实现了一种基于火工品技术的芯片毁伤方法,用于保护数据存储器的记录数据。测试结果表明:毁伤模块能够在无解保指令下对被恶意拆除的目标芯片进行摧毁,且毁伤模块在待机情况下能够长时间工作超过120 h。满足系统的方案设计需求。

巷道破底工作面机头收煤装置设计

为解决当前巷道破底工作面漏煤问题,通过对现有设备的结构特点及存在的问题进行分析,设计出一种巷道破底工作面机头收煤装置。该装置不仅可以有效地收集漏落的煤块,而且还可以提供采煤机维修操作空间,有效改善井下工人的工作环境,降低安全隐患,使得智能化工作面快速推进,从而为煤矿高产、高效提供有力支持。

基于水动力空化的微通道设备研究进展

针对微通道设备中的水动力空化现象,从限流元件的几何形状及尺寸、工作流体和通道粗糙度3个方面分析了其影响规律.限流元件的常见形状主要有微孔、微文丘里、微隔膜和微柱,不同几何形状的限流元件具有不同的空化流动特性;限流元件自身的尺寸参数以及尺寸缩小引起的尺度效应都对空化流型起着重要作用.常用的工作流体包含去离子水、乙醇、磷酸盐缓冲盐水(PBS)、制冷剂(R-123)、聚乙烯醇(PVA)微泡(MBs)悬浮液、全氟戊烷(PFC5)悬浮液、二氧化钛(TiO_(2))纳米颗粒悬浮液、多元液体混合物等;与水相比,其余工作流体均不同程度地提高了空化强度.粗糙度的引入主要体现于通道的表面粗糙元件和侧壁粗糙元件,其空化强度相较于光滑表面得到明显提高.微通道水动力空化设备主要应用于能量收集、液相剥离和生物医学领域.基于近年来国内外对微尺度水动力空化的研究现状,设想了微通道设备中的水动力空化现象的潜在研究方向及应用趋势.