Relaxes the brake, the heavy item then voluntarily fast drops, reduces the return trip time, but this kind of hoisting jack structure is complex.

放松制动器，重物即可自行快速下降，缩短返程时间，但这种千斤顶构造较复杂。

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As an example of the application, the changing structure of the diameter of an even-aged Jack pine stand is simulated and forecasted.

作为应用实例，对一块小叶松林分直径结构的变化进行了动态模拟和预测。

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By analyzing the structure of upright post and hydraulic jack, this essay introduces the structure of a rational and practical upright post or hydraulic jack, which also can be repaired easily.

前言：通过对立柱、千斤顶的结构进行对比、分析，介绍了合理、实用并便于检修的立柱、千斤顶应具有的结构。

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Watson and Francis Crick's description of DNA's double-helix structure, and in computing, with Jack Kilby's and Bob Noyce's independent inventions of the integrated circuit.

FORBES: Magazine Article