The acoustic wave impedance coefficient is recovered from the incomplete data of the far field pattern. 对于系数反问题进行了研究，利用远场模式的不完全数据反演声波阻尼系数。
The landau damping rate is obtained by solving the dispersion equation of relativistic longitudinal plasmons with the sub-light-velocity numerically. 摘要在亚光速区，对处于相对论性振荡的纵等离激元色散方程进行数值求解，得到了朗道阻尼系数的数值解。
