You question actually also brought up some other new concepts, such as variable displacement engine, and Hybrid, etc.

你的问题也能引出一些新的观念，比如，变冲程的发动机和电汽混合机等等。

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Through a study in characteristic curve of the engine and hydraulic pump, the matching efficiencies between engine and fixed and hydraulic variable displacement pump were analyzed respectively.

综合发动机和液压泵的特性曲线，分别对发动机与液压变量泵、定量泵进行了匹配效率分析；

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The systems comprise two engine-driven, electrically controlled, variable displacement hydraulic pumps and four large and four small hydraulically controlled, variable displacement hydraulic motors.

两个发动机驱动的电控液压泵（排量可变），四个大型和四个小型的液压控制马达（排量可变）。

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The systems comprise two engine-driven, electrically controlled, variable displacement hydraulic pumps and four large and four small hydraulically controlled, variable displacement hydraulic motors.

两个发动机驱动的电控液压泵（排量可变），四个大型和四个小型的液压控制马达（排量可变）。

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