A balanced three-layer sample rotation pattern is presented in this paper to solve the problem of rotation for the quarterly surveys with three-stage sampling designs.

本文构造了一种平衡的三层次样本轮换模式，解决了三阶段抽样季度调查的三层次样本轮换问题。

youdao

It was a bit of a surprise, given that most solar observations show a pattern of about 28 days - the rotation rate of the surface of the sun.

这令人感到小小的惊讶，因为大多数太阳观测显示出一个以28天为周期的模式——这正是太阳表面的旋转周期。

youdao

Arranged in a spiral pattern, the sketches are positioned to follow the planet's rotation.

素描按照火星的自转排成螺旋状。

youdao

But the discovery that the area surrounding the tachocline varies its rotation in a regular pattern could be a clue to solving the mystery.

BBC: Sun has strange 'spin cycle'

Between 1980 and 2000 the pattern was a gentle rotation of peaking at 22 weeks and then declining as economic fortunes improved to 12 weeks.

FORBES: Labor Pains

So far, the two trends have produced an encouraging trading pattern on Wall Street: Sector rotation.

FORBES: Wall Street: The Beginning or the End of a Correction?