Conventional four-stroke engines produce power by moving a piston up and down using rapid explosions of fuel and air in a cylindrical chamber.

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Its Variable Compression Engine can alter its compression ratio (the volume in a cylinder when the piston is up compared with the volume when it is down) from 14-1 to 8-1, depending on the circumstances.

ECONOMIST: Fuel economy

This may surprise nonpilots, but cranking up airplane engines--whether piston, turboprop or jet--has always been multistepped.

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The piston then moves back up to sustain the reaction in the upper reactor, and so on.

ECONOMIST: Nuclear power

Diffrient was a frustrated industrial designer with pioneering achievements, including the first chair whose height could be adjusted via a gas piston and spring, and a fold-up office table that replaced screws and plates with simple interlocking hinges.

FORBES: The Chair Men