查询词典 third boundary value problem

In the analysis, firstly, the flux boundary condition is used to simulate the frictional heat resource between wheel and rail. The non-steady heat transfer between the contacting surfaces of the wheel/rail, heat-convection and radiation between the wheel/rail and the ambient were all taken into consideration. Therefore, a heat coupling model of the wheel/rail in rolling/sliding is put forward to calculate the frictional temperature rise in the wheel and rail. Secondly, after the temperature distribution of wheel/rail, due to friction, is calculated, substitute the thermal load with equivalent fictitious body force and boundary distributed force loaded on the nodes of the corresponding elements. The wheel-load is applied to the center of the wheel.

首先，用热流边界条件模拟轮轨接触界面的摩擦热源，考虑轮轨间的非稳态热传导、轮轨自由表面与环境的热对流、热辐射的影响，建立轮轨滚动接触热耦合有限元计算模型，分析计算轮轨滚、滑工况下的摩擦温升；其次，以求得的轮轨温度场结果作为求解轮轨应力场的已知条件，轮载以集中力形式直接加载于轮心处，将摩擦温升引起的热载荷等效为假想体力和热边界面力，施加于相应的单元节点上，建立了轮轨热—机械载荷耦合作用的热弹性平面应力模型，分析热—机械载荷作用下的轮轨应力场。

We found that individual sensorimotor neurons in freely behaving swamp sparrows expressed categorical auditory responses to changes in note duration, a learned feature of their songs, and that the neural response boundary accurately predicted the categorical perceptual boundary measured in field studies of the same sparrow population.

在田野调查纪录期间，他们发现在野外沼泽带鵐学习歌唱时，个体的感觉运动神经对外在变化表现明确的听觉反应，且神经反应的分界可以准确预测绝对感知的分界，此在相同的沼泽带鵐族群中可被侦测到的。

The first order absorption boundary condition is applied to the outside boundary, which can avoid the error caused by the plane wave assumption.

在外边界上统一应用适合于人工源的一阶吸收边界条件来形成边值问题，可减小基于平面波假设造成的人为截断边界的影响。

From the composite section, it can be found that some fossils'range zones are too short. Maybe it is caused by the fossils not preserved properly or the samples not collected comprehensively. Most fossils'first occurrence data are later than the ages which are defined by the MIDK4 composite section. It is probably caused by the Foraminifer zones in Tethyan- Himalaya which are not isochronous with other areas. It can also be recognized that there are two major extinction and revival events at the boundary of Cenomanian/Turonian and the boundary of Coniacian/ Santonian. They are coincident with the two Ocean Anoxic Events and can be considered as the typical response by creatures.

在复合剖面上可以发现：一些化石的延限非常短，这可能是由于化石保存不完整或者样品采集不全造成的；大部分化石的首现面年龄值都要晚于MIDK4数据库复合剖面给出的年龄值，这可能是由于特提斯喜马拉雅带与全球其他地区的有孔虫化石带不等时造成的；同时，可以在复合剖面上识别出在Cenomanian/Turonian界线附近和Coniacian/Santonian界线附近存在两次大规模的生物灭绝和复苏事件，这正好与两次大洋缺氧事件发生的时间一致，可以作为缺氧事件的生物标志。

Firstly, the equation for stress intensity factors under static uniform pressure is used as the reference case, and then the weight function for a thick-walled cylinder containing a radial edge crack can be worked out. Secondly, the dynamic stresses in uncracked thick-walled cylinders are solved under internal impulsive pressure by using mode shape function method. The solution consists of a quasi-static solution satisfying inhomogeneous boundary conditions and a dynamic solution satisfying homogeneous boundary conditions, and the history and distribution of dynamic stresses in thick-walled cylinders are derived in terms of Fourier–Bessel series. Finally, the dynamic stress intensity factor equations for thick-walled cylinder containing a radial edge crack subjected to internal impulsive pressure are given by dynamic weight function method.

首先采用静态内压下的应力强度因子作为参考解，得到了带径向边裂纹厚壁圆筒的权函数；然后用振型函数方法推导无裂纹厚壁圆筒在冲击内压下的动应力响应，分析中将相应的弹性动力学方程解分为满足非齐次边界条件的准静态解和满足齐次边界条件的动态解的叠加，利用傅立叶-贝塞尔级数展开，推导出了厚壁圆筒内动应力的响应历程和分布规律；最后由动应力权函数方法导出带径向边裂纹厚壁筒在冲击内压下的动态应力强度因子计算公式。

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。

After making the gauge transformation, the effect of long range interaction is equivalent to twisting the boundary field, and the expressions of the boundary condition are given. The induced model is similar to the one which contans Aharonov-Bohm effect potential.

通过引入与构型相关的酉变换，我们成功地将该系统转化为能够直接求解的类型，得到这种长程相互作用的效果相当于产生扭曲边界场，并给出了扭曲边界的具体形式，指出模型类似于具有Aharonov-Bohm效应势的Bariev模型。

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。

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。

The French are not suggesting a new EU treaty, but they have plenty of other wheezes.

法国人并不是在建议签署一个新的欧盟条约，但他们有许多其他的阴谋。

This letter was written by my brother.

这封信是我弟弟写的。