【摘要】 利用傅氏变换将一个三维偏微分方程反问题从时间 -空间域变换到频率 -空间域 ,使得该问题的差分格式求解维数减少 .构造了一个隐式差分格式 ,利用傅氏反变换将该问题的解变回到时间 -空间坐标系 .该方法减少了常规方法中对时间离散所产生的误差 ,同时提高了计算的效率 .更多还原

【Abstract】 With Fourier Transformation, an inverse problem of the partial difference equation in time-space domain is converted into one in frequence-space domain, and the dimension of difference scheme decreases. An implicit difference scheme is constructed. Finally the solution in frequence-space domain is converted into that in time-space domain. Since this method decreases the dimension and uses the fast algorithm of Fourier Transformation, it commits fewer errors for the conventional method and enhances calculation efficiency.更多还原