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- external periodic force 周期性外力驱动
- In this paper, the problem of controlling the Euler's dynamically buckling problems by means of the coupled feedback controlling and periodic force excitation were studied. 摘要研究了利用藕合反馈控制法和周期激振力法来控制欧拉动弯曲问题。
- The theoretical analysis shows that periodic forcing onlyexcites the polar motion with the corresponding period, and stochastic motion is oneexciting source with the best probability for the Chandler Wobble. 理论分析表明：周期性强迫运动只能激发与其周期相一致的极移运动，随机运动是Chandler摆动最主要的激发源。
- Fluid motion caused by an external force such as gravity. 流体运动由重力等外力引起的流体运动
- He is just listening in external of that room. 他正在那房间的外面留神听着。
- External periodical current constraint 外控周期电流约束
- That period was a bright page in the history of Chinese literature. 那个时期是中国文学史上光辉的一页。
- This news program only covers external events. 这一新闻节目只报道国外消息。
- Let us hope that the period of this injustice will be over soon. 让我们希望这个不公正的时期很快结束吧。
- She sets great store by external politeness. 她很注重表面的虚礼。
- Childhood is a period of rapid growth. 幼年是生长迅速的时期。
- He consulted the chronicles of the period. 他参考了这一时期的编年史。
- He had to decide within a given period. 他得在一定时间内作出决定。
- She has a detailed knowledge of this period. 她对这段时期的情况了解地相当详细。
- In that period auto sales hit a14-year low. 这时期汽车销售量达到14年来最低水平。
- An external force is one whose source is outside the system. 外力是来源于系统之外的力。
- In this period, unemployment reaches record levels. 这段时间的失业人数又达到了创纪录水平。
- Which period of history are you studying? 你正在学哪一段历史？
- The magnitude of the external virtual force is irrelevant. 外虚力的大小是无关的。
- Our external trade has expanded during recent years. 我国的对外贸易近几年来有所发展。
