- Aim To establish a kind of new Geostar/Loran-C integrated navigation system, which resolves the problem of active location in Geostar system.
- The office has been humming with activity.
- The threat of war has depressed business activity.
- There has been a lot of activity in the town today.
- The town was humming with activity.
- Methods We chose the active locations of MSM reasonably,and used capture-recapture method and multiplier method to estimate the size of MSM in a certain city of a province.