The resonance characteristics of the complex amplitudes of acoustic pressure scattering by an elastic thin spherical shell are investigated. In the R-matrix approach the analytical relations for the approximate determination of the partial resonance frequencies and widths are found. The conditions for effective "background" scattering suppression and selection of resonances caused by sound radiation of the shell on the bending and membrane vibrations are obtained. For quadrupolar sound scattering by shells of average thickness a correlation between the widths of the spectral lines of the zero order symmetrical Lamb wave (membrane type of vibration) and the chemical type of the shell metal is discovered.
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机译:万向节密封件-具有细长的球形密封表面,该表面可滑入较厚的外表面,以提供防尘密封等。AB DE4036616A两根轴(1、2)通过万向节连接,一根轴(2)装有一个球面联轴器(3)在第二轴的外球面内移动。第二根轴具有细长的球形密封表面(8),该表面在较厚的外表面内滑动。相互交叉的球形密封表面提供了有限的灰尘等进入的密封。密封唇(8a,9)密封了壳体的作用。优势-改进了对万向接头的保护,将砂砾损坏的风险降至最低。 AN 91194459 TI用于转速测量的脉冲环-倾斜的计数器部分沿环的外围压出,与传感器单元相互作用以确定速度和方向