acoustic wave sources and receivers的用法和样例：
- Tunnel refection seismology employs sources and receivers that are mounted inside the tunnel wall or tunnel face and aims to predict rock properties ahead of the tunnel.
- Here is relative motion between wave source and observer in the Doppler effect. That makes observers feel the phenomenon of changing in frequency.
- The disadvantages and improvements-to-be of the shockwave lithotripter are limited to its wave source and positioning system.
- monitoring multicast reachability between sources and receivers;