According to owners of the habit of reversing and parking, four probe detectors were installed in the car or the tail on both sides of the installation of two.

根据车主倒车和停车的习惯，四个探头探测器分别安装在汽车的尾部或者两侧安装两个。

youdao

To measure these minor deformations, scientists sent four gyroscopes into space in a mission called Gravity Probe b.

为了测量这种微小的变形，科学家们在引力探测- B计划中向太空发射了四个陀螺仪。

youdao

Probe is made of unique four tuples, as shown below

探测是一个惟一的四元组，如下所示

youdao

To measure that, the four gyroscopes in Gravity Probe B are made of fused quartz spheres, which will not expand or contract as the temperature changes.

ECONOMIST: A new satellite will test Einstein's magnum opus

The indictment, unsealed Thursday by federal prosecutors in San Francisco, is the culmination of a four-year federal probe into whether he lied under oath to a grand jury investigating steroid use by elite athletes.

NPR: Bonds Faces Perjury Charges in Steroids Case

The probe was built with four reaction wheels and needs three of them -- one for each axis -- to aim its telescope precisely at a distant star, deputy project manager Charlie Sobeck said.

CNN: Planet-hunting Kepler spacecraft in trouble