將蛋白酵素F1-ATP合成酶（F1馬達）放置於含有ATP的溶液後，可取得化學自由能而使其轉動，在轉動過程中會受到三個作用力影響：黏滯阻力、介質流體的布朗運動以及水解ATP所獲得的驅動位勢能，此三個作用力的影響會使得動力衝程以及熱衝擊在提供驅動F1馬達的貢獻比例上會有所不一樣。
本文會利用Langevin equation計算出在各個時間點上F1馬達轉動所在角位置，以及建構出等效驅動位勢能之外，還會計算出在各個角位置上動力衝程與熱衝擊對驅動F1馬達轉動的貢獻比例。
結果發現若布朗運動對F1馬達做正功，則驅動F1馬達轉動的機制為動力衝程，而且其所輸出力矩較大；若布朗運動對F1馬達做負功，則驅動F1馬達轉動的機制為動力衝程與熱衝擊參半，而且其所輸出力矩較小。

Placed protein enzyme, F1-ATPase (F1 motor) into the aqueous liquid that contains ATP, the chemical free energy will be released. This free energy is used to actuate F1 motor rotation. The speed of rotation will be affected by the following forces: viscous drag force, medium fluid Brownian force and driving potential force by ATP hydrolysis. The contributions of power strokes and thermal excitations actuating the F1 motor rotation will be different under the effect of these forces.

Employing the numerical simulation of the Langevin equation, a sequence of F1 motor angular position versus time is generated. The effective driving potential is then constructed. Finally, the relative contributions of the power strokes and thermal excitation on each angular position are estimated in this paper.

The results are found that when the positive work done by Brownian motion on the F1 motor, the mechanism of motor is power strokes and the output torque from motor is strong. However, when the negative work done on the F1 motor, the mechanism of motor are both power strokes and thermal excitations, but the output torque is small.

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