查询词典 extremal element

This paper makes a three-dimensional model for QCM and analyzes directly the coupled phenomenon of the structural and electric fields of QCM with finite element analysis software ANSYS10.0. Through analyzing the convergence of the resonant frequency of QCM, the correctness of the finite element analysis is proved. The influence of different sizes of electrode on vibration of QCM and an optimal size of electrode is discovered, namely thickness of 100 nm and radius of 3 mm. The design of mesa on crystal plate is provided to solve the problem that the energy trapping is not good enough. This design proves valid based on finite element calculation and an optimal size of the mesa is given, namely height of 9.8 μm.

基于有限元分析软件ANSYS10.0对石英晶体微天平进行三维建模，验证了建模的正确性，并对不同电极结构尺寸进行仿真计算，对出现的耦合情况进行了分析，通过实验结果对比，提出较佳电极尺寸结构为厚度100 nm，半径3 mm；为解决金电极能陷效应不够理想的问题，提出在晶片上下表面筑平台的设计，有限元计算结果表明此设计能改善电极区的能陷效应，并且较佳平台高度为9.8μm。

Firstly the elastic stage of the cutting tool and workpiece in rectangular element is modeled and the relationship between the element node force and element node displacement also deduced.

首先选用矩形单元对刀具和工件弹性阶段进行有限元建模，得出其单元节点力和节点位移之间的关系，然后利用普朗特路斯方程，推导工件材料塑性变形时单元节点力和节点位移之间的关系，并指出金属由弹性变形到塑性变形时其单元刚度矩阵变化的规律，从而为实现金属切削过程的数值模拟提供可靠的理论基础。

The 3D Newtonian isothermal flow of normal double-thread screw element, normal triple screw element and VCR element was simulated.

第二部分则是在熔体输送段引入VCR元件，通过对常规双头螺纹元件、三头元件和VCR元件流道进行三维等温流场的模拟与分析。

The numerical analyses also showed that VCR element has the best distribute mixing effect and normal double-thread screw element take the second place, normal double-thread screw element is the weakest among them.

模拟结果表明：常规双头螺纹元件分散混合能力最强，常规三头螺纹元件次之，VCR元件最弱；而VCR元件分布混合能力最强，常规三头螺纹元件次之，常规双头螺纹元件最弱。

When one element of an N-element array is aberrated, the most sensitive aberration is Piston error, and then the sensitive aberrations are element defocus, tilt, spherical aberration, coma and astigmatism. As for four aperture system, the influence of Piston error is 2 times larger than that of defocus, and 4 times larger than that of astigmatism.

在合成孔径成像系统单个子孔径存在像差的情况下，Piston误差对系统的影响最大，其次是离焦误差、倾斜误差、球差、彗差和像散，对于四孔径系统，Piston误差对系统的影响几乎是离焦误差的2倍，像散的4倍。

As a result, some ideas about the fabrication are put forward.The EPMA experiment results show that the main element such as W, Mo, Ti, Ni, Cu, Fe element are changed gradually in W-Mo and W-Mo-Ti FGM. In the layer rich in W, the grain are intervained and are mixed mechanismly. The same is to the layer rich in Mo and W-Mo. These grain felt up by some sinter. In Mo-Ti layer rich in Mo, the grains are also mixed mechanismly. Ni, Cu, Fe element assembled at interface. Ni melt by Cu plays an vital role in sinter effect. The microstructure characteristics result show that the compactness of W-Mo and W-Mo-Ti FGM is good.

电子探针实验结果表明W-Mo系、W-Mo-Ti系梯度功能材料中主要元素W、Mo、Ti、Ni、Fe、Cu分布整体上具有梯度变化规律，发现富W区、富Mo区、W-Mo混合区中颗粒交错分布，基本上以机械混合的形式存在，颗粒之间主要靠烧结剂的粘结作用实现致密化；以Mo为主要组分的Mo-Ti混合区，也是以机械混合的形式存在；Cu溶解于Ni形成固溶体更好地起到活化烧结能力，Ni、Cu、Fe在宏观层间界面富集，有利于烧结致密化。

According to the shell finite element theory, the proposed method was based on the simulation of corrugated steel web by orthotropic plate element and that of flange plate by isotropic plate element respectively.

为了提高波形钢腹板箱梁的结构计算精度，本文根据板壳有限元理论提出了一种新的空间计算方法。

In this dissertation, the arch bridge was discretized by the FEM according to its structural characteristics with the spatial beam element simulating the tied beams, end floor beams, middle floor beams, arch ribs and the like and with the spatial link element simulating the suspenders to erect the bridges spatial mechanical computational finite element model.

该拱桥的拱肋主要承受压力，弯矩较小；系杆梁虽然是一拉弯构件，但由于布置有多道预应力筋，截面全跨受压；吊杆张拉力比较均匀，且吊杆张拉力对桥面系的线形控制作用比较明显；桥梁各构件受力和变形均在桥梁设计规范规定范围之内，表明桥梁结构受力合理。

The paper gives stiffness matrix and mass matrix in finite element analysis of the ground vibration problem caused by track traffic by using three-dimension finite element method. Because three-dimension finite element analysis is very difficult, it is transmitted into a quadratic programming, which can be calculated by neural network.

本文融合神经网络技术和遗传算法，对轨道交通引起的地面振动进行了正分析和反演，并利用计算机技术实现了地面振动的三维动画模拟，这主要包括：(1)研究了压缩映射遗传算法，利用Banach空间的不动点定理证明了压缩映射遗传算法可以收敛到全局最优值，弥补了标准遗传算法不能收敛至全局最优值的不足。

Congenital element, because be born before, of pregnant woman hidebound, systemic sex disease, certain and familial genetic element (if the tooth is mixed,the character of jaw bone and size often affect a tooth, cause dental amlposition or jackknife to wait); Acquired element, basically be undesirable habit (consistent side sex is masticatory, buccal breath, make force of parity of tongue, lip, buccal share is destroyed, those who cause jaw growth is not not well-balanced, harmonious) with all sorts of tooth disease.

先天因素，由于出生前，孕妇的营养不良，全身性疾病，某些家族的遗传因素（如牙齿和颌骨的性状和大小常常影响牙位，造成牙齿错位或重叠等）；后天因素，主要是不良习惯（如一侧性咀嚼，口呼吸等，使舌、唇、颊部分均势力量受到破坏，导致面颌发育的不匀称、不协调）和各种牙病。

You can buy sweetened beverages, if that suits you.

你若喜欢的话，可以买些含有糖精的混合饮料。

As many of you are probably aware, Nick and Vanessa were recently faced with an embarrasing sex scandal after naked pictures of the two getting jiggy with it in a hot tub surfaced the net.

正如很多你可能知道，尼克和 Vanessa 最近面临一个尴尬的绯闻事件后，赤裸裸的图片两个越来越jiggy与它在浴缸中的一个热点浮现净。