• Journal of the Korean earth science society
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• v.30 no.6
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• pp.787-798
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• 2009

A new apparatus was presented in order to help understand the concept of the Coriolis force which is essential in understanding the trajectories of the atmospheric current and the tide of seawater. In the apparatus proposed in high-school textbooks, since the slide from which the ball is released is set outside the rotating disk, it was not possible to interpret, with the trajectory of the ball on the disk, the motion of the atmosphere and the current of seawater occurring as a result of the Coriolis force. In order to resolve such problem, a new apparatus was developed in which the slide was set on the disk and rotated with the disk. Experiments were carried out using both the existing apparatus and the new apparatus, and the results were compared. While, in the experiment performed with the existing apparatus, it was difficult to analyze the trajectory of ball because the motion of the ball was not smooth when it hit the disk, in the experiment with the new apparatus it was much easier to analyze the trajectories. It was also possible to compare the trajectories when the initial velocity of the ball was varied.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.976-977
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• 2006

선형전동기와 같은 선형운동을 하는 기기에서 원형운동을 하는 경우 속도가 0 이되는 부분에서 비선형적인 마찰력이 작용하며 이로 인한 운동괘적의 외곡 현상이 발생한다. 본 연구에서는 이러한 마찰력을 비롯한 모든 외란을 하나의 비선형적인 외란으로 간주하여 실용적으로 사용할 수 있는 간단한 형태의 외란 관측기를 제시한다. 또한 모든 외란 관측기에서 피할수 없는 문제의 하나인 전동기 관성(모멘트)의 변동 문제를 해결하기 위하여 제한적이지만 매우 효과적으로 관성을 추정해낼 수 있는 새로운 방법을 제안한다.