屈曲

Properties of nonlinear buckling deformation of round soleplate with slot structure under concentrated load are studied.

运用MSC.Nastran求解器计算了薄壁圆柱壳在轴向压力作用下的临界载荷、屈曲模态及薄底板在集中载荷作用下的非线性屈曲问题。

The critical buckling loads and buckling modes are described by eigenvalues and eigensolutions in symplectic space.

在辛几何空间中，将圆柱壳的临界屈曲载荷和屈曲模态归结为辛本征值和本征解问题。

In a symplectic space,eigenvalues and eigenfunctions take the place of the critical buckling loads and buckling modes of the problem.

对于壳体的前屈曲问题可采用小变形理论，而后屈曲问题则需采用几何大变形理论。

When the Hamiltonian system is introduced into the research of dynamic buckling in cylindrical shells, the problem uses dual variables in Symplectic space instead of variables in traditional Euclidean space. The symplectic eigenfunction expansion method gives out an exact solution space. So many problems are solved, which can not find the solution in traditional methods.

将哈密顿体系引入结构的动态屈曲研究中，其意义在于将结构的动态屈曲研究从传统的欧几里得几何空间进入到由原变量和对偶变量组成的辛几何空间之中，从而使辛本征函数展开的直接解析法得以实施，这样就可以求解许多以往半逆凑合法无法求解的问题，并且所得到的解空间是完备的。

A Hamiltonian system was constructed for the fundamental problem of the dynamic buckling ,thereby problems of critical loads and buckling modes were reduced to determinations of eigenvalues and eigensolutions in a symplectic space and a symplectic method was proposed.

针对有内压或外压的弹性圆柱壳在轴向冲击载荷耦合作用下的动态屈曲问题，构造哈密顿体系，在辛空间中将临界载荷和动态屈曲模态归结为辛本征值和本征解问题，从而形成一种辛方法。

Eigenvalue buckling analysis can only forecast the theoretical buckling strength of an ideal linear elastic structure, because of the unideal property of material and geometrical nonlinearity, most structures can not reach their theoretical strength limit.

特征值屈曲分析只可预测一个理想线弹性结构的理论屈曲强度，材料非理想性与几何非线性使得大多数结构无法达到它们理论强度极值。

Critical voltage for a simply supported rectangular thin plate under uniform electric field is presented by using Navier solutions.

基于经典板理论，假设材料的电弹参数为板厚方向坐标的幂函数，采用含压电耦合项的修正层合理论，推导了压电功能梯度薄板在电载荷作用下的屈曲方程，并利用Navier解，得到四边简支矩形薄板在均匀电场下的屈曲临界电压。

Based on the geometric deformation, finite element and false structure methods,this paper analyses and deduces the calculating method for the critical strength of the strut -type axile pressure members.

本文利用几何变形协调、有限元和其轭法对具有撑杆轴压构件屈曲的数值计算方法进行了理论分析和推导。所建立的计算方法概念清楚，使用方便，这为进一步进行撑杆式预应力钢管混凝土轴压构件屈曲分析建立了理论依据

In the thesis the author analyzes the tripping of stiffened panels by three different methods. Based on the above method, the author calculates the ultimate longitudinal strength of a boxlike girder, several ships and many stiffed panels by program. And then checks with some famous experts results. The result is approving. Also the author analyses the reliability of ship considering corrosion. At last an experiment is done to verify the theory.

由于加筋板侧倾屈曲是一种非常危险的破坏形式，本文采用不同方法分析了加筋板侧倾屈曲，并作出了比较；基于上述方法运用计算机程序计算出了箱型梁和几种实船的极限承载能力以及各种加筋板单元的极限强度，并和著名学者的结果进行了比较，结果令人满意；分析了某实船的考虑腐蚀影响的可靠性指标；最后，为了验证理论的精确度，作者参与了钢箱型梁的极限强度试验，通过比较试验数据与理论数据，结果基本一致。

They found that the joint moments measured at any given motion increased with greater magnitudes of joint displacement, and were significantly larger in the two most caudad facet joints (L4 L5 and L5 S1).62 With lateral bending, strains of the joint capsule tended to be larger in magnitude in the three most caudad joints(L3 S1) during contralateral flexion (i.e., the left facet joints are most strained during right lateral flexion),whereas the two most cephalad joints (L1 L2 and L2 L3)bore the greatest strain during bending to the ipsilateral side.

当向对侧弯曲时侧弯时最尾端(L3 S1)的三个椎体的小关节囊的拉伸强度增大（例如右侧屈曲时左侧小关节达到最大的应力）。而头端的两个关节(L1 L2 和L2 L3)在向同侧屈曲运动时拉伸力量最大。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。