activity-on-arc network planning的用法和样例：
- There is a lot of activity on the stock exchange.
- The Research, Application and Main Problems on Arc Sensor.
- There had been little activity on the street.
- It introduces the development and application of traditional network planning technique based on CPM and PERT.
- That professor had ever been very active on the world scene.
- Disables protection of your work in the network. All network activity on your computer will be allowed.