二面的

The mutual coherence and angular correlation function of scattered wave from two dimensional non-Gaussian rough surfaces is deduced using the Gram-Charlie distribution, then the pulse scattering from two dimensional rough sea surface is calculated, and pulse broadeding is discussed.

基于Gram-Charlie分布函数并利用三阶统计特性推导出了非Gaussian二维粗糙面的双频互相关和角相关函数的计算公式，并以二维海面为例计算了其对几种典型波形脉冲的散射，讨论了脉冲展宽效应。

The pressure correction method is used to calculate the two-dimensional turbulent flow in general curvilinear coordinates.

按照进气箱对称面的形状，给出一种简化的二维进气箱几何模型，用微分方程法生成贴体的曲线网格，在任意曲线坐标系下采用压力修正法数值模拟了其内部二维湍流流动。

Experimental results demonstrate that the pretreatment on the cleaved edge affects the overgrowth and that selective etching is better than natural oxidation for site-controlled growth of quantum wires.High temperature degasification will induce pits on GaAs spacers,indicating that Ga atoms can easily escape from (110) cleaved edges.

实验结果显示超晶格解理面的预处理方法对二次外延有重大影响，其中择优腐蚀比自然氧化更有利于量子线的定位生长，过高温度的脱氧除气会导致解理面的GaAs部分出现坑状结构，表明（110）面上的Ga原子容易脱附。

A dodecahedron with twelve regular pentagons as faces.

有十二个正五角形面的十二面体。

The excited-state intramolecular proton transfer tautomerism reaction of 6-methyl-4-hydroxy pyri-midine monomers and dimmers was investigated by the ab initio method with the self-consistent reaction field with Tomas's polarized continuum mode and CIS theories at HF level on the basis of 6-311+G* and 6-31G basis set. By studying the potential energy surface, it was found that the monomer's ground-state proton transfer process together with the excited-state proton transfer process is a molecular system of four energy level, but dimmers were not, which can be used to explain the fact that UV-visible absorption and fluorescence spectra of monomer and dimers all corresponded to quinoid.

采用 ab initio HF理论的组态相关CIS方法和连续溶剂模型PCM，分别在6-311+G*和6-31G水平上研究了6-甲基-4-羟基嘧啶单体及二聚体激发态质子转移的异构化反应；对其反应势能面的研究发现，单体基态和激发态的异构化反应一起可以形成四能级的分子电子体系，而二聚体的却不能，由此解释了单体和二聚体的紫外吸收光谱和荧光发射光谱均对应于酮式构型的原因。

The growth and nucleation rates of〓 cleavage face of YbYAB crystal are all very fast, because so many growth steps and growth centers were formed within only 2～3 second at the temperature near the saturate point. No spiral growth steps can be found, so growth mechanism is twodimensional nucleation. When the flux temperature increases for only 0.5℃ above the saturate point, the spiral melting holes are formed. The transformation from growth morphologies to melting morphologies is very sensitive to the temperature. When the temperature increases another 1℃, the spiral melting holes transform into two-dimensional nucleation melting holes.

YbYAB的〓解理面的生长及成核速度都非常快，在比饱和点低0.5～1℃的温度下，当生长2～3秒钟时，可以看到许多生长中心与生长台阶的形成，在较宽的台阶上还可以看到二维核的形成，没有看到螺旋中心，说明生长机理是二维成核生长；当温度比饱和点高0.5℃时，在〓解理面上形成螺旋状熔坑，这表明形貌由生长到熔化的转变与温度的关系是非常敏感的；当温度比饱和点高1.5℃时，螺旋状熔坑转变为二维成核状熔坑。

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。

It is difficult to be simulated and analyzed due to the excessive surfaces, complex structure and locomotory parts in zoom lens. All the transmission planes taken as the partial reflection and partial transmission planes were simulated with ASAP（advanced system analysis program）and the stray rays on "dangerous surfaces" which easily generate the ghost images in zoom lens were analyzed. Based on it, the zoom lens was optimized and the quality of image was improved by changing the curvature and refractive index of the second reflection planes.

利用ASAP软件模拟每个透射面作为部分透射、部分反射的表面，对变焦光学系统非轴上光进行分析，模拟出变焦系统的光学元件表面和光机内壁，实行实际光线追迹，然后以像面为研究对象，进一步实施实际光线追迹，模拟出全部散射光在像面上的能量分布，找出鬼像形成的原因，并在此基础上通过改变二次反射所在面的曲率或改变所在面的折射率两种方法对变焦光学系统进行优化，减小鬼点数目，以提高系统的成像质量。

Compared with methods appeared in literatures, our algorithm, with high accuracy, sensitivity and correctness, complete adaptively the correct distinction between interferential fringes and backgrounds. In chapter four, methods for the computer operatable description of line and region features are discussed, which contains: Computation curve's curvature in quantity, Fringes' separation distance , Contour's smoothness of region, Similarity of varied curves.

在第三章中，本文研究的是以线条为直接目标的图象分割方法——条纹抽取，在研究分析了许多条纹抽取方法以后，针对激光全息焊点缺陷检测这一课题中的复杂数字光学图象LHII条纹抽取进行了多方面的研究，主要有：分别从点对应、邻域特性对应推导并提出了几个信息分离算法；结合光学图象形成方面的知识，提出了变周期余弦分割二值化方法；结合当前条纹走向、毗邻条纹走向及可靠条纹点约束条纹跟踪，在许多方面，改进并发展了常规的条纹跟踪算法，实现了无人-机交互的全自动条纹跟踪抽取。

Third, mensurated the front axles load-time history when truck was running on general tar-paved roads, mountainous roads and the proving ground enhancement roads, second sampled and pretreated to the load-time history with RPCⅢ software of MTS corporation, acquired the relationship of the frequence of the mean and amplitude load, obtained the zero mean equivalent loads using Goodman experiential fatigue equation, acquired the Weibull distributing functions of equivalent loads of respective roads.

第三，测定了汽车前桥在一般沥青公路、山区公路和试验场强化试验路面的载荷时间历程。对载荷时间历程进行了二次采样和数据预处理。采用雨流计数法得到了各路面的载荷均、幅值的频次关系，并根据Goodman经验疲劳公式，得到了零均值的等效载荷及相应的频次。利用数理统计的方法得到了各路面的等效载荷的Weibull分布函数。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷