压电薄膜微传感器振动模态的仿真分析

以压电本构方程为基础，建立了压电薄膜微传感器机电耦合的有限元模型，采用有限元分析软件ANSYS7．0对压电薄膜微传感器进行了模态分析，同时分析了压电薄膜微传感器的结构尺寸对振动模态的影响，探讨了影响压电薄膜微传感器工作稳定性和响应速度的关键因素，结果表明为了提高压电薄膜微传感器的工作稳定性和响应速度，应该在符合工艺要求和保证其它特性的前提下，尽量减小微悬臂梁结构长度，增加多晶硅层厚度，限制PZT层厚度，而微悬臂梁宽度的影响较小。     

低损耗梳状声表面波延迟线的耦合模分析

梳状换能器可看成若干叉指单元电端并联,声端首尾串联而成的网络,采用单向结构可降低采用这种结构的声表面波延迟线的损耗。根据耦合模(COM)理论推导出整个换能器的混合矩阵(P矩阵)并结合等效电路模型得到了整个延迟线二端网络的导纳矩阵以及延迟线的幅频及相频响应。本方法能模拟指间反射、三次行程、指条寄生阻抗以及外围电路对器件的影响;理论模拟与实验结构吻合。     

变频调速应用技术（十一）——第六讲经济效益赞变频（上）

本文分析了节能问题的几个方面。主要有：负载需求与节能的关系，调速方法与节能的关系，以及大马拉小车的节能问题等。     

对称型双偶氮蒽醌三阶非线性光学材料的合成

有机大分子三阶非线性光学材料是目前功能材料研究的热点,分子设计的关键在于有机大π共轭体系.根据该原理设计合成了三个具有大π共轭体系的新型双偶氮蒽醌结构的有机大分子三阶非线性光学材料.合成以1,5-二氨基蒽醌为原料,经亚硝酰硫酸重氮化,分别和苯胺、苯酚及邻甲酚偶合,得到双(4-氨基苯)-1,5-二偶氮蒽醌,双(4-羟基苯)-1,5-二偶氮蒽醌和双(3-甲基-4-羟基苯)-1,5-二偶氮蒽醌,反应产率达47%～62%.通过核磁共振氢谱、元素分析、质谱、红外和紫外对其结构进行了表征,并对反应过程进行了分析和讨论,方法简单、可行.     

用测向力显微镜对力／电／热耦合作用下金表面力学行为的研究

对微构件力／电／热等多域场下力学行为的研究有着重要的意义，利用原子力显微镜采用纳米压痕法对样品金在力-电-热耦合作用下的表面力学性能进行了研究，实验表明在压痕过程中，无论在无电场作用下还是有电场作用下，压痕周围的金属由于挤压形成了凸起，从扫描得到的形貌图中可以明显的看出，压痕周围的亮区为材料被挤出的区域．此外，在外加直流电场作用下，随电流的增大，硬度值有增大的趋势，而残余压痕和弹性模量都呈现减小的趋势．     

Loose Coupling and Healthcare Organizations: Deployment Strategies for Groupware

Healthcare organizations are often organized in a modular, loosely coupled fashion where separate and semi-autonomous work units specialize in different areas of care delivery. This partitioning allows each unit to adapt to emerging practice standards in its area of expertise and to adjust to its local work environment. However, organizational loose coupling can limit the flow of information within organizations and can make it difficult to coordinate services when patients’ care is dependent on professionals from more than one unit. Groupware systems have the potential to improve coordination and information access in healthcare organizations. However, modularity and loose coupling make it difficult to introduce new systems when they span more than one unit, since authority is not always centralized and since perceptions and frames of reference on new deployments differ across units. In this paper, we define a groupware deployment framework for loosely coupled healthcare organizations that has two parts: a set of deployment challenges and a set of deployment strategies. The deployment challenges include: difficulties centralizing deployments, perceptions of inequity, role conflicts, and problems achieving critical mass. The deployment strategies outline a preliminary set of approaches for addressing the difficulties of deploying CSCW systems in loosely coupled healthcare organizations. We illustrate the framework by presenting a case study of a groupware deployment in a home care setting.     

正交波导纵/横向耦合裂缝的散射特性

用正弦伽略金法分析了纵/横向耦合裂缝的散射特性，导出了计及波导壁厚度的积分方程。进一步分析了正交耦合的主模散射特性，分析了S参数之间的关系，计算了标准X波段矩形波导的S参数随缝隙长度、偏置的变化关系。给出了不同偏置、波导尺寸情况下谐振长度和散射特性的数值结果。这些结果已成功地应用于波导馈电裂缝阵列设计中。     

改性纳米CaCO3/HDPE复合材料性能的研究

在HDPE中加入高分子偶联剂改性的纳米CaCO3，测试了复合材料的力学性能和流变性能。发现高分子偶联剂的加入改善了无机粒子和聚合物间的结合，促进了无机粒子在体系中的均匀分散，使体系的力学性能上升，高分子偶联剂的最佳使用量（质量分数）是1％；纳米CaCO3的加入减小了体系的弹性，增加了刚性，改善了材料的挤出特性，对体系的流变性能没有产生大的影响。     

多机紧耦合YH数控线切割系统通信与控制子系统的设计与实现

针对多机紧耦合YH数控线切割系统通信与控制子系统的设计与实现课题，讨论了在Windows环境下实现主CPU与从处理器控制板的通信与加工控制方法，对多机紧耦合系统中的通信代码设计、数控加工控制软件设计及其在YH数控线切割系统上的实现作了详细的叙述。     

Numerical simulation of a sheet metal extrusion process by using thermal—mechanical coupling EAS FEM

The thermal-mechanical coupling finite element method(FEM) was used to simulate a non-isothermal sheet metal extrusion process.On the basis of the finite plasticity consistent with multiplicative decomposition of the deformation gradient,the enhanced assumed strain(EAS)FEM wasd applied to carry out the numerical simulation.In order to make the computation reliable and avoid hourglass mode in the EAS element under large compressive strains,an alterative form of the original enhanced deformation gradient was employed.In addition,reduced factors were used in the computation of the element local internal parameters and the enhanced part of elemental stiffiness.numerical results show that the hourglass can be avoided in compression region.In the thermal phase,the boundary energy dissipation due to heat convection was taken into account.As an example,a circular steel plate protruded by cylindrical punch was simlated.The step-wise decoupled strategy is adopted to handle coupling between mechanical deformation and the temperature variation.By comparing with the experimental results.the numerical simulation was verified./