91色情片

A programmer at Sandia National Laboratories in California has patented a
machine that automatically mends holes in the road. About the size of a
single-decker bus, the Rapid Road Repair Vehicle scans the road using an array
of sensors on its bumper. When it finds a pothole or crack, it first cleans up
the area with a high-pressure air hose, then vacuums up any debris. A filling
material, such as aggregate, is then tamped into place with a fast sealant and
dusted with grit to provide grip. After a further vacuum session, the RRRV moves
on to the next pothole, at about 15 kilometres per hour.