It is either engine driven, or powered by the harvestors themselves.

它要么是由发动机驱动的，要么是由收割者自己提供动力。

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An energy calculation model is established for the gas engine driven heat pump based on the experiment of components.

在对燃气机热泵部件进行实验的基础上，建立了燃气机热泵系统能耗计算模型。

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The gas engine driven heat pump (GHP) is driven by the gas engine using gas, and driven the compressors for refrigeration circle.

燃气热泵是利用燃气驱动燃气发动机，并带动压缩机进行制冷循环的空调装置。

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The first works to be digitised will range from feminist pamphlets about Queen Marie-Antoinette (1791), to the invention of the first combustion engine-driven submarine (1858), and an account of a stuffed Hippopotamus owned by the Prince of Orange (1775).

ENGADGET: British Library and Google Books partner up to digitize 250,000 out-of-copyright works

These algorithm-driven engine controls allow the LT1 with a valvetrain architecture that dates back to the Eisenhower administration to produce an estimated 450 horsepower and 450 pound-feet of torque, enough to launch the car to 60 mph in less than four seconds, GM promises, while at the same time returning highway mileage of around 28 mpg.

WSJ: 2014 Chevrolet Corvette Stingray: Drive All-American | Rumble Seat by Dan Neil

But the heat-driven Stirling engine design opens up possibilities for alternative fuels.

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