参考系

In the second chapter, elementary theories and ideas of one step forming inverse approach were described and warped modification method, implemented by Cook, was introduced into one step forming simulation and based on idea of surface spreading; new quadrilateral element modification arithmetic was put forward. By spreading warped quadrilateral onto plane in local coordinate system, a plane quadrilateral element whose shape and area were equal to original warped quadrilateral element was gotten and internal force vectors of four nodes and stiffness matrix of elements were improved to increase precision of simulations on this plane element.

第二章从一步成形逆有限元法的基本理论和思想出发，将Cook基于弹性理论的四边形单元的翘曲修正算法引入基于塑性的一步成形，并且基于曲面展开的思想，本文提出一种新的四节点单元翘曲修正方案，通过把翘曲的单元展开的方法在局部参考系中得到一个与实际翘曲单元的形状与面积非常接近的平面单元，在该平面单元中进行单元刚度及内力向量的计算，进一步改善模拟结果的精度。

The specific application of the system is given, for example, ballistic curve movement, rigid pendulum and reference system of movement.

以弹道曲线运动、刚性摆和运动参考系为例给出了系统的具体应用。

The inertia force and coriolis force are calculated to draw deviation for opposite balance, fall and plane motions close to the earth, based on the particle motion differential equation to no-inertial frame of reference.

在质点对非惯性参考系的运动微分方程的基础上，计算惯性离心力和科里奥利力对地球表面附近物体的相对平衡，落体运动和平面运动引起的偏差。

First, according to a phase matching condition of electromagnetic wave on the stationary boundary surface, we find the refelection and transimission angles in the front system with a static ionization front. Then using the transformations of wave vector and frequency we get the corresponding angles in the laboratory system in which the ionization front is moving at relativistic speed.

首先在波面参考系中根据电磁波在固定边界上的相位匹配条件，确定电磁波在静止电离波面上的反射角和透射角，并利用波矢和频率的相对论变换，导出了在实验室参考系中相应的反射角和透射角的表达式，最后对所得的结果作了进一步的讨论。

Actually I don't know the details of how our local galatic group is moving in this frame (perhaps a cosmologist reading this will tell me), but certainly our acceleration is also extremely tiny.

我们的本星系群在这个参考系中如何运动我并不很清楚（也许哪个宇宙学家可以告诉我），但可以肯定那个加速度是极端微小的。

MRF approach ; train induced wind ; cross wind ; flow field ; aerodynamic forces of train ; aerodynamic forces of bridge

多重参考系法；列车风；横向风；流场；列车气动力；桥梁气动力

Analysing the reasons of floating for objects in the reference system of non-inertia, the paper discusses the relationship between the depth and time, as well as the floating object and its acceleration, these relationships will provide convinient to explain some questions of the hydrostatics.

摘要通过分析浮体在非惯性参考系中浮沉的原因，探讨浮沉的深度与时间的关系、浮沉体积与加速度的关系，这些关系将给解释一些流体静力学问题带来方便。

The present method shows that angular momentum of the planet wheel about a fixed axis is equivalent to transport angular momentum and relative angular momentum.

推导了行星轮的运动分解为随转动参考系的转动和相对于转动参考系的转动时，计算其对定轴动量矩的一个新方法。

I point out that mechanics does not provide adequate foundation for the description of all natural phenomena. We should have a new understanding that in the 'change of location' of the same event of inertial system there exist two different reference systems that are mutually in uniform rectilinear motion. This new understanding will avoid the puzzle brought about by physicists' obscure yet obdurate conception as to which of the two mutually uniformly moving reference systems is not related to the inertia reference system.

我指出力学为一切自然现象描述所提供的基础是不够充分的，重新认识惯性系的同一事件"位置的改变"存在着两个互相匀速直线移动着的两种不同参考系，可以避免物理学家们模糊、执着地认为惯性参考系究竟是用两个互相匀速移动着的参考系中哪一个无关所带来的困惑。

Facing the empirical facts of natural objects, I believe that an inevitable remedial opinion can be concluded for 'relativity principle' of mechanics: the law that governs the changes of the motion of objects in inertial system corresponds to which of the two mutually uniformly rectilinearly moving reference systems is used to describe 'the changes of location' of these movements.

面对自然客体的经验事实我认为可以得出对力学&相对性原理&的一个必然的修补意见：惯性系物体运动据以变化的定律，同描述这些运动&位置的改变&的参考系究竟是用两个互相匀速直线移动着的哪一个参考系相对应。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。