36 research outputs found

    Design and manufacture of array sphygmology sensor

    Get PDF
    提出了一种用微机电系统(MEMS)技术应变传感器阵列探头客观细腻地采集人体脉象的新思路。探头采用直接腐蚀出电阻条的技术,具有工艺简单、成本低廉、电阻变化率高、工作可靠等优点。对设计进行了理论计算和优化,并用有限元分析软件ANSYS8.0进行了结构和电耦合场仿真,模拟悬臂梁端点位移对电阻变化的影响。当悬臂梁末端位移变化为50μm时,电阻变化率模拟结果为18.84%,与理论计算值19.67%符合得很好。For acquiring more comprehensive information of pulse conditions,a probe of pulse symbol instrument designed by MEMS technology has been presented,the method of direct etching of silicon is utilized to form the resistor.The process is simple,economical,and it has high change rate of resistor,working reliability.After theory calculation,the coupled-field analyses between the structural and electric fields are carried out by finite element analysis software ANSYS 8.0.It simulates the change of resistor with the displacement of cantilever tip.When the tip of cantilever displaces 50μm,the modulation result is 18.84%,and is in good agreement with the calculation result of 19.67%

    开放大学的建设和发展——专家访谈录

    Get PDF
    建设开放大学是教育部确立的国家教育体制改革试点项目之一,其试点性质决定了“边解读、边探索是开放大学建设实践模式的重要特征“。在理论和实践层面,有关“开放大学建设的基础理论““开放大学的性质和功能““开放大学的学术标准和质量保证“等重大问题是一个理论解读和实践探索相互印证、共同推进的过程。思想从来都不是自言自语,行动也不能是闭门造车。为此,我们便有了这样一个“专家漫谈开放大学建设和发展“的设想策划,相继走访了部分国内高校有着不同教育学科背景,包括远程教育、高等教育、成人教育、职业教育、教育技术等的专家学者。我们相信,不同的学科视角、不同的理论语境聚焦共同的问题,收获的不仅仅是倾听,更是一种对话,是一曲“差异和共通的和鸣“

    Optimization of the upper surface of hypersonic vehicle based on CFD analysis

    Get PDF
    For the hypersonic vehicle, the aerodynamic performance becomes more intensive. Therefore, it is a significant event to optimize the shape of the hypersonic vehicle to achieve the project demands. It is a key technology to promote the performance of the hypersonic vehicle with the method of shape optimization. Based on the existing vehicle, the optimization to the upper surface of the Simplified hypersonic vehicle was done to obtain a shape which suits the project demand. At the cruising condition, the upper surface was parameterized with the B-Spline curve method. The incremental parametric method and the reconstruction technology of the local mesh were applied here. The whole flow field was been calculated and the aerodynamic performance of the craft were obtained by the computational fluid dynamic (CFD) technology. Then the vehicle shape was optimized to achieve the maximum lift-drag ratio at attack angle 3 degrees, 4 degrees and 5 degrees. The results will provide the reference for the practical design

    晶体硅光伏电池烧结工艺及调节

    No full text
    0引言丝网印刷/快速烧结工艺是当今工业化大规模生产晶体硅太阳电池普遍应用的成熟的金属化技术。快速烧结工艺是将印刷在电池片的正面电极

    基于uCLinux和Jupiter的嵌入式通讯设备的设计

    No full text
    介绍基于韩国ADC公司的JUPITER32位EISC高效双以太网处理器,并辅以LXT971A为以太网物理层接口的低功耗、高速硬件电路的设计;并介绍了如何在嵌入式操作系统uCLinux上进行嵌入设备通信程序的编写,实现了嵌入式设备的网络化信息交流与控制。最后介绍了一个采用这些技术的一个实际应用

    混沌系统的非线性连续预测变结构控制与同步

    No full text
    This paper presents a predictive variable structure control method for the control and synchronization of chaotic nonlinear dynamic systems based on a unified frame for both the control and the synchronization. Two controllers are designed. One is the predictive controller for nominal model, and the other is a variable structure controller for system perturbation. The tracking control of reference signal is realized, and the method has the merit of robustness of variable structure control. The effectiveness of the proposed method are proved by numerical simulations

    混沌系统的非线性连续预测变结构控制与同步

    No full text
    This paper presents a predictive variable structure control method for the control and synchronization of chaotic nonlinear dynamic systems based on a unified frame for both the control and the synchronization. Two controllers are designed. One is the predictive controller for nominal model, and the other is a variable structure controller for system perturbation. The tracking control of reference signal is realized, and the method has the merit of robustness of variable structure control. The effectiveness of the proposed method are proved by numerical simulations

    固态合金中的非线性振荡现象观察

    No full text

    准噶尔盆地南缘原油金刚烷分布特征

    No full text

    双发动机高超声速乘波飞行器性能分析

    No full text
    当以超燃冲压发动机为动力的高超声速飞行器以马赫数大于5 的速度飞行时,激波阻力和摩擦阻力急剧增大,并引发一系列构型设计难题,除在气动方面形成所谓“升阻比屏障”外,还需满足发动机来流要求、整机推阻匹配及容积率约束等难题,同时,这些约束或需求之间还存在相互耦合和矛盾,这进一步加大了构型设计的难度。本文基于一种全参数化乘波飞行器设计方法,设计了一种双发动机模块高超声速飞行器构型,并对其进行了数值性能分析
    corecore