• 가정의 벗
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• v.37 no.12 s.436
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• pp.8-9
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• 2004

옛날에는 함께 술래잡기나 딱지치기를 하고 놀았었지만 지금의 아이들은 컴퓨터 앞에 앉아 철저히 혼자만의 시간을 가진다. 급변하는 사회속에서 자시의 또래와 비슷한 사람을 보유하려는 심리가 왕따를 만드는 것은 아닌가 생각해본다. 건강한 아이들의 성장을 위해 더 많은 관심이 필요한 때다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.4
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• pp.213-220
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• 2023

This paper presents a model simulating the folding process and collision dynamics of "ddakji", a traditional Korean game played using paper tiles (which are also referred to as ddakji). The model uses two A4 sheets as the base materials for ddakji. The folding process involves a series of boundary conditions that transform the wing part of the paper structure into a twisted configuration. A rigid plate boundary condition is also adopted for squeezing, establishing the shape and stress state of the game-ready ddakji through dynamic relaxation analysis. The gaming process analysis involves a forced displacement of the striking ddakji to a predetermined collision position. Collision analysis then follows at a given speed, with the objective of overturning the struck ddakji--a winning condition. A genetic algorithm-based optimization analysis identifies the optimal collision conditions that result in the overturning of the struck ddakji. For efficiency, the collision analysis is divided into two stages, with the second stage carried out only if the first stage predicts a possible overturn. The fitness function for the genetic algorithm during the first stage is the direction cosine of the struck ddakji, whereas in the second stage, it is the inverse of the speed, thus targeting the lowest overall collision speed. Consequently, this analysis provides optimal collision conditions for various compression thicknesses.