例句與造句

1. Backward difference approximation
   后向差分近似法
2. Backward difference operator
   后向差分算子
3. Backward difference method
   后向差分法
4. 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
   第一章中我們對小參數(shù)對流占優(yōu)擴散問題提出了新的數(shù)值方法? ?特征混合有限元方法，即對方程的對流部分采用沿特征線的后退差分格式求解，以保證較小的截斷誤差限并避免了在流動的鋒線前沿數(shù)值彌散現(xiàn)象的出現(xiàn)；對流動的擴散部分采用最低次混合元方法求解，以保證格式對未知函數(shù)及伴隨向量的同時高精度逼近。由于該方法中檢驗函數(shù)可取分片常數(shù)，此格式在某種意義上具有局部守恒性質(zhì)。
5. It's difficult to find backward difference in a sentence. 用backward difference造句挺難的