势能

The element rigidity equation of spacial beam element was deduced using nonlinear geometric equation and total potential energy with stationary value, and the characteristic equation of the first type stability.

利用非线性几何方程和总势能驻值原理推导了空间梁单元的刚度方程，并由此建立了第一类稳定问题的特征方程。3。

The equations of the train and deck truss girder bridges time varying system were set up by using the principle of total potential energy with stationary value in elastic system dynamics and the "set in-right-position" rule for forming structural matrices.

应用弹性系统动力学总势能不变值原理及形成矩阵的"对号入座"法则，建立列车－桥梁时变系统的整体振动方程。

Both motor car and each trailer of HST were modeled as a multi-rigid-body system with two suspensions, and LVT was modeled as an assembly of track segment elements with 24 degrees of freedom. The vertical vibration matrix equation of the system was established on the basis of the principle of the total potential energy with stationary value in elastic system dynamics and the rule of "set-in-right-position" for formulating system matrixes, and then Wilson-θ numerical integration method was used to solve the problem. The dynamic responses of the system were calculated when the train runs at the speed of 200 km/h. And the effects of vertical stiffness of rail fastener and block pad on vertical vibration responses of the system were investigated.

其原理是：将高速列车的动车和拖车模拟为具有二系悬挂的多刚体系统；将弹性支承块式无碴轨道模拟为具有24个自由度的轨段单元的集合；基于弹性系统动力学总势能不变值原理及形成系统矩阵的"对号入座"法则，建立此系统竖向振动矩阵方程，并采用Wilson-θ数值积分法求解，计算速度为200 km/h时此系统竖向动力响应，研究轨道刚度对此系统竖向振动响应的影响规律。

Based on the principle of total potential energy with stationary value in elastic system dynamics and the rule of "set-in-right-position" for formulating system matrixes, the vertical vibration equation set of the high-speed train and slab track time-dependent system was established considering the vertical connecting condition between the wheel and the rail.

考虑轮轨竖向位移衔接条件，基于弹性系统动力学总势能不变值原理及形成系统矩阵的"对号入座"法则，建立了高速列车－板式轨道时变系统竖向振动矩阵方程；分析了CA砂浆的刚度和阻尼时此系统竖向振动响应的影响规律。

In the real switchback, where friction prevents the car from again reaching as high a point as that from which it started, there is still a continuous change between kinetic and potential energy.

在实际的升降滑道（图19）中，虽然摩擦力使小车不能重新达到像出发点那样的高度，但是仍发生动能和势能之间的不断转换。

In this paper we separate the Hamiltonian into three parts: a spherical symmetry Hamiltonian; a z-component of the angular momentum operator, and a non-spherical symmetric potential as the perturbation operator, and provide a propose method by separating the potential containing squared magnetic field B^2 into two parts spherical symmetric and non-spherical symmetric ones so that the first-order energy correction due to the non-spherical symmetric potential is zero, and the second-order correction due to B^2 can be obtained by a simple variational method.

采用变分法和微扰法相结合的方法，把高强度磁场中氢原子的哈密顿H分为三部分：球对称哈密顿；z分量角动量算符相应部分和非球对称势微扰，并用一种特别规定的分解法将哈密顿H中含磁场平方项的势能分解为球对称与非球对称两部分，且使非球对称部分引起的一级修正能量值为零，并采用一种简便的变分法直接求出B^2对能级的二级修正值。

Firstly, kinetic energy and potential energy expressions are obtained by a series of derivation, considering the extrinsic momentum. In the symplectic system, control equations of longitude and transverse coupling vibrations of rotating elastic structures, or Hamilton canonical equations are described. So the solution of the problem is boiled down to the eigenvalues and eigensolutions in the symplectic space.

首先，从能量的观点出发，通过一系列的理论推导，给出旋转结构的动能和势能表达式，并考虑外动量的影响，从而得到在辛体系中描述旋转结构纵向和横向耦合振动的控制方程，即哈密顿正则方程，于是将问题归结为辛几何空间的本征值和本征向量问题。

For the ternary system results were in qualitative agreement with experimental values.

这说明使用简单的势能模型，难以准确计算这些物系的相行为。

What a waterfall thunderously sets off is but hte accumulated potential that a reservoir quietly stores. So tranquility is where an enriched life comes from.

正如水库是在宁静中积蓄力量，瀑布在热闹中宣泄势能一样，一个人应该在宁静中丰富自己的人生。

In capillary network, the movement of fluid between the blood and tissue fluid is determined by two opposing forces

在微血管网之中，血液和组织液的互换是由血液和组织液中的两个力量所控制：血压差异，渗透势能差异。

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