后退差分 meaning in Chinese

receding difference

In chapter one , we propose a new mixed method called characteristics mixed finite element method for a convection - dominated diffusion problems with small parameter e : we handle the convection part whth backward difference scheme along the characteristics , obtain much smaller time - trunction errors and avoid numerical dispersion on the front of the peak curve of the flow : we use a lowest order mixed finite element method to deal with the diffusion part , so this scheme can approximate the unknow function and its following vector with high accuracy at the same time
第一章中我们对小参数对流占优扩散问题提出了新的数值方法? ?特征混合有限元方法，即对方程的对流部分采用沿特征线的后退差分格式求解，以保证较小的截断误差限并避免了在流动的锋线前沿数值弥散现象的出现；对流动的扩散部分采用最低次混合元方法求解，以保证格式对未知函数及伴随向量的同时高精度逼近。由于该方法中检验函数可取分片常数，此格式在某种意义上具有局部守恒性质。