失稳

The nonlinear stability of three-dimensional disturbances for the Blasius boundary layers is studied. We adopted here the high accuracy method of using the expansions in orthogonal functions along the normal direction and the effective algebraic mapping to deal with the problem in the infinite region. The initial solutions of two-dimensional harmonic waves are given by Landau expansion, and the mean-flow-distortion is calculated by the approximation equation.

运用Landau展开给出了二维谐波的初始解、通过求解线性PSE而得到TS波和C型亚谐扰动的初始站值、以及近似地模拟初始站的均流变形值，以此为初始条件，并结合迭代-预估校正方法来实现非线性PSE的求解和推进，详细地研究了非平行边界层三维扰动C型失稳过程。

The more anisotropic the plant stalk is, the more obvious the Brazier effect is.

植物茎的泊松比整体减小，其抗失稳能力稍差，反之稍强。

In this paper, the factors that may cause crack breaking of concrete pavement of several built highways were analyzed systematically and thoroughly. From analysis to site experiments and calculation, it is believed that crack breaking is mainly caused by factors as follows: 1 、 Unqualified sedimentation and losing stabilization of the roadbedinduced crack in the early; 2、 Construction technology、 materials and incorrect treatment methodswere adopted;3 、 Crack breaking induced by thermal stress; 4、 Water cant circulate makes crack cause;With regard to the afore-mentioned problems, corresponding preventive measures, qualified control indices and site control approach are presented based on analysis theory and site experiments.

本文在全面系统地分析已建成的高速公路水泥混凝土路面产生的原因的基础上，通过现场试验及计算分析，确定了高速公路水泥混凝土路面裂缝的主要影响因素有以下几个方面： 1、路基的不均匀沉降、失稳是早期裂缝产生的主要因素； 2、施工工艺、材料问题及养护方法不当； 3、温度应力产生的裂缝； 4、排水不畅影响裂缝产生；针对上述问题，通过理论分析及现场数据提出相应的质量控制目标、现场控制方法。

The instability of breakwater induced by interaction between short-crest waves and seabed has been addressed in the last chapter.

分析了短峰波和底床相互作用所引起的防波堤失稳问题。

Consequently, how to prevent destabilization and make use of the buckling strength is the primary coverage of this course.

因此，如何防止失稳和利用屈曲后强度，将是本课程的主要内容。

The research on cataclysmic law of landsliding disaster is the basis of it\'s research on prewarning system.

边坡工程失稳灾害灾变机理的研究是其预警系统研究的重点。

The catastrophe theory conditions and displacement formula of critical off-stability point is carried out.

提出了突变条件和临界失稳点的位移值公式。

With random disturbances on the inlet of the jet, axisymmetric instability appears firstly and then the large coherent structure—vortex ring is formed.

在模拟自然射流的随机扰动的条件下，射流首先出现轴对称失稳，形成大尺度拟序结构一涡环。

The cable and the tension bar which belong to the basic frame member of the prestressed long-span steel structure system are high strength steel members which had been subject to cold-work hardening and hot rolling and modified treatment separately.

预应力大跨度钢结构体系的大变形倒塌失稳极限状态是结构安全的控制因素，其基本构件索与拉杆的延性性能分析研究对结构体系的安全设计至关重要。

It is shown that the mechanical properties including Young's modulus, tensile strength, critical strain and stress under buckling can be enhanced with the decreasing of intershell spacing. The shear strength can be enhanced by 2-3 orders of magnitude when the intershell spacing is reduced to 20%, which is also dependent on commensuration. Zigzag-type carbon nanotubes have higher shear strength. The axial stress in tubes when the load transferring from outmost tube to inner tube is observed as well.

研究了单壁纳米管束横截面的六方化失稳现象，给出各种管径的面内压力－应变关系曲线；每条曲线都给出一个明显的拐点而且有很强的非线性；线弹性模量与参考构形有关，也受管直径的影响；分析了管束横截面的晶格不稳定性特征，表明晶格的缺陷能够明显的减小临界值；模拟了在不同应变下纳米管束对静水压的反应，发现不同压力下的截面形态不同，在很高压力下相邻管之间会形成化学键。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。