接触

The third approach is about the concept of an ITO direct Ohmic contact structure on GaP window layer. The direct Ohmic contact structure is performed by the deposition of an AuBe diffused thin layer and the following activation process on the surface of a Mg-doped GaP window layer. The presence of this thin AuBe diffused layer yields the Be dominant metallic surface layer and significantly reduces the barrier height between the ITO and p-GaP layer. Via the modification of contact structure, not only the brightness was significantly increased but the reliability was comparable to the conventional LED without this structure.

第三个研究为一种具有直接欧姆接触在p型磷化镓窗层与氧化铟锡界面的制程方法，於本研究中并无习知砷化镓欧姆接触层的存在，我们利用金/金铍金属藉由热退火程序，使其金铍原子在磷化镓窗层表面形成具金属特性之薄膜层，降低磷化镓与氧化铟锡接触产生之接面能障；另外，该元件在氧化铟锡直接欧姆接触於磷化镓窗层下，除亮度具明显提升外，在稍大电流(20毫安培)元件可靠度测试下，亦未有明显衰减情形发生。

The transformation of the contact force from contact point to nodes of contact elements is accomplished according to their shape.

并根据接触单元的形状实现了接触力从被接触点到接触单元节点的转化。

In order to solve the theoretical backlash problem of the teeth, which is crucial to the number of actual contact pairs of teeth in the research on multi teeth contact of crown gear coupling , the theoretical backlash of teeth flank with the concept of backlash angle is first time defined and described in the paper, and the minimization model of its variables is set up.

为解决鼓形齿联轴器多齿接触研究课题中的实际接触齿对数的关键技术轮齿理论间隙的问题，首次用间隙角的概念对轮齿理论间隙作了定义和描述；建立了该变量的极小化模型；对一鼓形齿联轴器作了实际优化计算，得出了鼓形齿联轴器多齿接触研究中计算实际接触齿对数所需的不同啮合状态下的最小间隙角

And the frontal technique is adapted to solve the FE equations. The techniques are studied to deal with the large slip frictional contactproblems between a deflectable body with large deformation and a rigid bodywith flat or curved surface. A new algorithm is presented to resolve such contactproblems, including incremental displacement constraints and force constraints,and the modules are programmed. The performances of tire under static load invertical loading state and camber state are analyzed by this method. And theexperiments were carried out at the same condition as used in analysis process.

研究了大变形柔性体与具有平面及曲面外形刚性体之间的大滑动摩擦接触问题，提出了求解这类接触问题的位移增量约束和主动力增量约束处理方法；编制了大变形柔性体与具有平面及曲面外形刚性体之间的大滑动摩擦接触问题求解模块；利用本文提出的大滑移接触问题处理方法，分析了轮胎在径向静载和静态外倾加载条件下受力和变形，并对部分分析结果进行了试验验证，验证结果表明，本文提出的位移增量约束和主动力增量约束处理接触问题的方法是正确可靠的，而且具有精度高、收敛性好、收敛速度快的优点。

Besides, contact stress in tibia component-polyethylene insert interface of three component design arise 31% to 34% only in dorsiflexion 40 degree and plantar flexion 40 degree due to flat smooth surface design.

二件式人工踝关节的接触压力平均为7.8 MPa，三件式人工踝关节胫骨元件-关节内衬接触面的接触压力平均为4.4 MPa最小；三件式人工踝关节关节内衬-距骨元件接触面的接触压力平均为5.7 MPa居中。

The contact area and contact pressure in anteromedial and posteromedial quadrant tended to decrease, while, the contact area and contact pressure in anterolateral and posterolateral quadrant tended to increase.

结果］通过模拟试验发现，腓骨短缩时，胫距关节总接触面积呈减小趋势，外、后外象限的接触面积、接触压呈增大趋势，而前内，后内象限的接触面积、接触压均减小。

The contact area and contact pressure in anteromedial and posteromedial quadrant tended to decrease, while, the contact area and contact pressure in anterolateral and posterolateral quadrant tended to increase.

结果］通过模拟试验发现，腓骨短缩时，胫距关节总接触面积呈减小趋势，前外、后外象限的接触面积、接触压呈增大趋势，而前内，后内象限的接触面积、接触压均减小。

In this dissertation, first, based on theory of cutting tooth about the gleason spiral bevel gear, the equation of meshing in the process of cutting tooth, the surface equation of generating gear as well as the general tooth surface equation of the double circular arc spiral bevel gear, using GB12759-1991 type of double circular arc gear as a basic gear profile, a three-dimension solid model of double circular arc spiral bevel gear which has the good adaptability was carried out by used of Unigraphics software;Second, by researching of the algorithm about contact and collision as well as various contact types based upon Contacting Finite Element Method, a foundation was laid for selecting the contact type in analyzing contact stress of double circular arc spiral bevel gearing;Finally, through the connection port of PARASOLID between UG software and ANSYS/LS-DYNA software, the three-dimension solid model of double circular arc spiral bevel gearing obtained above in UG was imported into ANSYS/LS-DYNA, a finite element analyzing about contact stress of double circular arc spiral bevel gearing was carried out by applying new loading method.

本文首先基于格利森弧齿锥齿轮加工原理及切齿啮合过程中的啮合方程、产形轮齿面方程以及双圆弧弧齿锥齿轮的齿面方程，选用GB12759-1991型双圆弧齿轮基本齿廓为基准齿形，利用Unigraphics软件的建模功能，绘制了有较好适应性的双圆弧弧齿锥齿轮传动三维实体模型。其次，描述了应用有限单元法进行实体接触与碰撞问题算法的公式，研究了有限元分析中的各种接触类型以及双圆弧弧齿锥齿轮接触应力分析中所选择接触类型的依据。最后，通过UG软件和ANSYS/LS-DYNA之间的PARASOLID接口工具包，将UG软件中得到的啮合齿轮模型导入ANSYS/LS-DYNA有限元分析软件，给出一种新的加载方法，进行了双圆弧弧齿锥齿轮传动的接触应力的有限元分析。

Based on the contacting characteristics of the surfaces in MEMS, we use the continuum contact mechanics modeling and fracture mechanics concepts to give a closed-form solution for the adhesion of the flat-ended wedges, including the atomic pressure distribution, the variations of the contact area and air gap with the load.

基于MEMS表面的接触力学特点，本文运用连续介质接触力学及断裂力学方法，研究了平底锥冲头的粘着接触问题，给出了接触区的原子压力分布、接触面积和表面间隙随载荷变化的封闭解。

The results show that, for the elasto-plastic contact of tip-substrate approach and separation process, the material plastic yielding in the atomic level is still governed by the von Mises criterion. For the adhesion of flat-ended wedges, continuum mechanics can be still applied down to a few lattice constants within the contact region, and give reasonable results, apart from the discrepancies near the contact edges. Moreover, adhesion hysteresis occurs during unloading due to the atomic steps, where the unloading curve does not coincide with the loading one. This in turn supports the presumption proposed by Pollock for the adhesion of stepped spheres.

本文首先对针尖—基体模型的弹塑性接触机理进行了深入研究，指出在原子水平上材料的塑性屈服仍由Von Mises准则控制；对平底锥冲头粘着接触的模拟表明，除了在接触区边缘附近有一定差别外，接触力学方法在接触区内几个晶格常数范围内仍能给出令人满意的结果；由于原子台阶效应，加载与卸载曲线不重合，出现粘着滞后，证实了Pollock关于具有纳米阶梯结构的球体粘着滞后现象的推测。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。