Time-harmonic waves propagate along a cylindrical waveguide in which there is an obstacle. The problem is to calculate the reflection and transmission coefficients. Simple explicit approximations are found assuming that the waves are long compared to the diameter of the cross-section d. Simpler but useful approximations are found when the lateral dimensions of the obstacle are small compared to d. Results for spheres, discs, and spheroids are given.

中文翻译：

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管中球体的散射以及相关问题。

时谐波沿着其中有障碍物的圆柱形波导传播。问题是要计算反射系数和透射系数。在假定波浪相对于横截面直径d较长的情况下，可以找到简单的显式近似。当障碍物的横向尺寸比d小时，可以找到更简单但有用的近似值。给出了球体，圆盘和球体的结果。