The second is Single Neural Adaptive PID Control which is adopted to realize coordinative control of two motors running for elevating motion in direction Z.

针对Z 向升降运动二级传动机构的协调控制问题，提出了摆线方程的机构运动切换策略和单神经元自适应PID 控制方法。

youdao

The motion of spherical pendulum in z-direction is described by nonlinear oscillation equation.

用非线性振动方程描述了球摆在 z 方向上的运动。

youdao

So, the direction of the force is going to be that of x, y, z.

所以方向是。

youdao

You just need to remember what's happening to z effective, which really tells us what's happening with all the trends, and once you know z effective, you can figure out, for example, what direction the atomic radius should be going into.

你只需要记住有效核电量的规律，实际上它会告诉我们所有的规律，只要你知道了有效核电量的规律，你就可以判断，比如，原子半径会向着哪个方向发展。

麻省理工公开课 - 化学原理课程节选