首先讨论了舰船辐射噪声的产生机理、构成和频率特性，指出螺旋桨噪声的振幅存在周期性调制。
First, the generation mechanism, components and frequency characteristic of radiated noise of naval ships are studied. There exists periodical modulation for the amplitude of propeller noise.
当一束聚焦的、调制的激励激光照射固体材料时，表面上除了产生周期性的温度分布，还产生局部的周期性形变。
When a focused, modulated exciting laser beam incidents onto a solid surface, besides generation of periodical temperature distribution, a periodical local surface deformation also occurs.
当两台激光器的抽运受到调制而每台激光器的损失不同时，两台激光器输出的强度会出现周期性运动、混沌同步和失去同步的情况。
When both of the lasers are pump-modulated with different losses, the output intensities of the two lasers show periodic motion, chaotic motion, chaotic synchronization and loss of synchronization.
应用推荐