The useful life of engineering plastics was predicted within the storage period using a polynomial fitting curve method, and its storage life deadline was inspected. 运用多项式拟合曲线方法对轻武器用工程塑料在贮存期内进行寿命预测，考核轻武器用工程塑料的贮存寿命期限。
On the basis of a composing method of universal harmonic trapezoid motion law, nondimensional general curve formulation of driven cam is built. 摘要基于通用简谐梯形组合运动规律的构成方法，建立了凸轮机构从动件无因次通用曲线方程。
