2012-07-20

Migration

Convergence

provisioning
thin provisioning

provision

headroom
1.There's a lot of headroom for such a small car.
这么小的一辆汽车的头上空间蛮大的。
2.There is not enough headroom for buses to go under this bridge.
这座桥梁下面的净空高度不够，公共汽车不能通行。
=>the amount of space below a roof or bridge
It's a small car but there's lots of headroom.

prerequisite
=>something which must exist or happen before something else can exist or happen
Passing a written exam is a prerequisite for taking the advanced course.
Public support is a prerequisite for/to the success of this project.
They had to agree to certain conditions as a prerequisite of being lent the money.

oversight
oversight meeting
by oversight