Acoustic Sensor Training Aids Program的用法和样例：
- Motion pictures, slides, and cards were used as training aids.
- The Russian aid program, it turned out, was a great mess.
- The relative weight of China's aid program in Fiji is worth noting.
- The time-varying Lorentz force causes ions vibrate in the medium, which can be detected by a sensitive acoustic sensor non-invasively.
- Is it possible that an acoustic sensor which size is only 10 cm can form a narrow directivity with a constantbeam of 20 degree?