The coefficient functions of the hyperbolic equations considered are assumed to be piecewise constant. 我们假设在所考虑的微分方程中，系数函数为片段常函数。
A global smoothing method based on polynomial splines is used to estimate the coefficient functions in functional-coefficient linear autoregressive models. 摘要基于多项式样条全局光滑方法，建立函数系数线性自回归模型中系数函数的样条估计。
