second degree equation的意思|示意

The driveline for a tractor vehicle is simplified as a 2-DOFs(degree of freedom)torsional vibration system, and is described as a second-order differential equation.

将牵引车的传动系简化为一个2自由度的扭转振动系统，并以二阶微分方程描述。

Second-degree polynomials equation of maize(Zea Mays L. ) grain yield with both planting density and nitrogen fertilization was established by means of regression analysis.

本文从不同种植密度和施氮量对玉米籽粒产量的影响，建立了二次多项式回归方程。