This margin depends on the size and speed of an aircraft, and re-ordering the queue can minimise the delay before all the planes get into the air (mathematicians call this the departure problem).

ECONOMIST: Algorithms

In today's competitive business world, margins are being compressed, but speed is still a source of margin.

FORBES: Commentary

They even allow you to set one number for areas where the speed limit is under 50 and another margin of excess for over 50.

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