查询词典 boundary condition

First, the physical models associated with dislocations and cracks are respectively converted to mixed boundary value problems in mathematics. Secondly, by using the Fourier transform, a dual integral equation for a crack and an algebraic equation for a dislocation can be derived from the boundary conditions relating with a crack and a dislocation, respectively. Solving these equations, exact analytical solutions can be obtained in terms of Bessel functions in close-form.

先把位错和裂纹的物理模型写成与它们相关的边值问题，然后，利用Fourier变换将这些边值问题化成一个对偶积分方程(对位错而言，得到一个代数方程)，求解此对偶积分方程，可以获得以Bessel函数给出的封闭形式的分析解。

In this paper,we consider the existence and uniquness of solution for Dirichlet problem of the Helmholtz equation on the domain with corners, i.e problemFor smooth boundary,we use potential theory to transform the problem into second kind boundary integral equation ,and use Fredholm alternative theorem,we obtain the existence and uniqueness of Dirichlet problem.

在本文中，我们考虑边界含尖点的有界区域上Helmholtz方程△u+k~2u=0的Dirichlet问题即问题与问题解的存在及唯一性。

To obtain the unknown intermediate vector function needs to solve a Fredholm integral equation of the first kind, the solution of which can only be determined with a difference of a vector proportional to the normal of the boundary and its integration on the boundary must zero.

可是要求出该积分表达式中待定的边界上的向量密度函数要导致求解第一类Fredholm 积分方程。

Methods From the fundamental equation in Laplace domain, using Multiple Reciprocity Method-Boundary Element Method, the integral equations and the boundary integral equations are derived and solved numerically.

方法由 Laplace 变换域中的基本方程出发，利用多重互换边界元方法，得到了积分方程和边界积分方程，并求得数值解。

Taking advantage of gauge transformation and dipolar approximation, we qualitatively derive rotating Bose-Hubbard model.Then finite temperature phase boundary between superfluid phase and normal state in rotating Bose-Hubbard model is analytically derived by studying the stability of normal state in rotating bosonic optical lattice.We also analytically prove that as the function of rotation angular velocity the oscillation of critical hopping matrix directly follows the upper boundary of Hofstadter butterfly.

4通过做一个规范变换和偶极近似，定性地推导了旋转Bose-Hubbard模型，并且通过研究正常态不动点的稳定性推广了旋转Bose-Hubbard模型的零温相图到有限温度的情形；另外根据系统有效的能带宽度与旋转速度的关系(Hofstadter蝴蝶)，得到了系统的临界跃迁矩阵随旋转速度的改变展示谐振行为的结论。

Differing from the general BEM that is attributed from the general boundary integral equation, The natural boundary element method attributed from the natural BIE has not only the advantage of the dimensionality, but is confirmed and gain the only NBIE from the original problem.

无网格方法仅仅需要节点信息，克服了有限元等传统数值方法对网格有较强依赖性的缺点，摆脱了网格的束缚，避免了大量的网格分划、复杂的网格生成及重新划分的工作，减少了因网格畸变而引起的困难，而且收敛快、精度高、易于实现和进行后处理工作。

Himalaya, which formed on the basement of the Pan-African orogenic event at about 550 Ma BP and experienced Ordovician to Devonian platform sedimentation, was transformed into to a back-arc extensional-rifted zone at the end of the Carboniferous. The Yarlung Zangbo ophiolitic mélange zone is a Mesozoic back-arc spreading basin corresponding to the Gangdise paleo-island arc zone on the south side of the Tethyan Ocean. The Gangdise zone experienced island-arc orogeny in the Late Paleozoic. The very significant differences in geology on both sides of the Bangong Co-Nujiang suture zone suggest that the suture zone is not only the northern boundary of Gondwanaland and the boundary between the Indian (Yunnan-Tibet) stratigraphic realm and the South China (Qiangtang-Sanjiang) stratigraphic realm, but also the relics of subductional collision and final extinction of the Phanerozoic Tethyan Ocean after the breakup of the Neoproterozoic supercontinent Rodinia. The basic point of study of the collisional orogenic processes of the plateau is the structure and composition of the archipelagic arc-basin tectonic realm of three different stages bounded by three rigid paleocontinental blocks (Gondwanaland, Laurasia and Pan-Cathaysian) and the mutual constraining, transformation and coupling of various material movement forms.

喜马拉雅奠基于5.5亿年左右的泛非造山事件基底上，历经奥陶纪至泥盆纪台地沉积，并于石炭纪末转化为印度板块北缘的弧后伸展裂陷带；雅鲁藏布江蛇绿混杂岩带曾是特提斯大洋南侧与冈底斯古岛弧带相对应的中生代弧后扩张盆地；冈底斯带曾经历了晚古生代岛弧造山作用；班公湖-怒江带两侧大量地质特征重大差异表明，班公湖-怒江带是冈瓦纳大陆北界，是印度地层区和华南地层区的分界，是新元古代Rodinia超大陆解体后显生宙特提斯大洋俯冲，消减，碰撞，最后消亡的遗迹。

There are various complex interactive relationships between the original system and the environment system in an expending system; therefore the band boundary becomes a gradational boundary.

在全系统中，由于本体系统与环境系统之间会产生各种各样非常复杂的相互作用关系，因而本体系统的边界就成了一个具有丰富层次的环带边界。

On one hand, the grain boundaries are the sites of microcrack nucleation, microcracks first occur at grain boundary zone, whose propagation type depends on lamellar orientation of both side of grain boundary.

一方面，微裂纹首先萌发于晶界区，其扩展方式取决于晶界两侧片层的取向。

Boundary representation, involves actually drawing the boundary of the model so that it appears on the display of a graphics terminal.

界限表示法，介入实际上得出模型的界限，以便它在图形终端的显示出现。

Objective To investigate the relationship between ovum fertilization rate and sperm morphology, acrosome reaction in IVF and to explore the influence of parameters of sperm on fertilization rate.

目的 研究体外受精(in vitro fertilization，IVF)中精子形态、顶体反应与卵子受精率之间的关系，分析精子各参数在IVF受精率方面的参考意义。

A: I hear Mr. White wants to run for the Presidency!

我听说怀特先生要参加总统竞选！