• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.1
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• pp.25-31
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• 2001

The theoretical modeling to predict the modulus of elasticity by the shape memory effect of dispersed particles in a metal matrix composite was studied. The modeling approach is based on the Eshelbys equivalent inclusion method and Mori-Tanakas mean field theory. The calculation was performed on the TiNi particle dispersed Al metal matrix composites(PDMMC) with varying volume fractions and prestrains of the particle. It was found that the prestrain has no effect on the Yonugs modulus of PDMMC but the volume fraction does affects it. This approach has an advantage of definite control of Youngs modulus in PDMMCs.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.15-22
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• 1999

This paper demonstrates the feasibility of Shape Memory Alloy (SMA) actuators in controlling the motion of micro active catheter. The dynamic behavior of SMA is obtained by several experiments for the design of the controller. With the control parameters obtained in experiments, temperature feedback control algorithm is proposed and realized. The prototype of micro active catheter is fabricated, and its control performance which uses the designed controller is investigated. The results obtained show the potential of the SMA as viable means for actuating the micro active catheter.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.67-71
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• 2003

A hot press method was used to create the optimal fabrication condition for a Shape Memory Alloy(SMA) composite. The bonding strength between the matrix and the reinforcement within the SMA composite by the hot press method was more increased by cold rolling. In this study, the objective was to develop an on-line monitoring system in order to prevent the crack initiation and propagation by shape memory effect in SMA composite. Shape memory effect was used to prevent the SMA composite from crack propagation. For this system an optimal AE parameter should be determined according to the degree of damage and crack initiation. When the SMA composite was heated by the plate heater attached at the composite, the propagating cracks could be controlled by the compressive force of SMA.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.738-742
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• 1996

In the present paper, We have tried to reconfirm the "Interlligent" material properties using both the sintered TiNi/A(1100) matrix composite by powder metallurgy method. By using these specimen, Shape meorystrengthening effect in tensile strengthand fatigue crack propagation above inverse transformation temperature of TiNi fiber were investigated. More over, by SEM obsevation, the effect of the residual stress at the interface between A1 matrix and TiNi fiber and some brittle precipitation layers such as inter metallic compounds on fracture mechanisms was metallurgically discussed.discussed.

• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.198-200
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• 2002

경제적이며 정확한 3차원 전자탐사 모델링을 위해 위해 Habashy et al. (1993)에 의해 제안된 국소 비선형 근사(localized nonlinear approximation)를 이용하여 전자탐사 모델링 알고리듬을 개발하였다. 전자탐사 수치모델링시 많은 계산시간 및 기억용량을 필요로 하는 Green 텐서 적분을 정확하고 빠르게 계산하기 위해, 단일 미소체를 이용한 공간파수 영역에서의 Green 텐서 적분 알고리듬을 제안하였다. 더욱이 Green 텐서의 송수신 방향 및 상반성을 고려하여 각각의 미소체에 의한 전체 미소체에의 Green 텐서 적분을 한 개의 미소체에 의한 전체 미소체에의 Green 텐서 적분 값으로 구하게 하므로 매우 적은 기억용량 만으로 Green 텐서 적분 행렬을 구성할 수 있어, 역산법에 효과적으로 적용할 수 있다. 이 수치 모델링 알고리듬을 기본으로 하여 평활화 제한을 가한 최소자승 역산 알고리듬을 개발하였다. 이 역산 알고리듬을 지표 전자탐사 및 시추공-지표 전자탐사 등에 적용하여 PC에서도 빠르게 3차원 전자탐사 역산이 수행됨을 보였다.

• Korean Journal of Human Ecology
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• v.21 no.4
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• pp.705-714
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• 2012

This study investigated the relationships among emotion knowledge, negative emotionality, and autobiographical memory in a sample of 131 three- to five-year-old children attending day care center in seoul. The collected data were analyzed using simple regression and hierarchical multiple regression. The main results of this study were as follows. First, children's emotion knowledge exerted negative effects on their negative emotionality. Second, children's negative emotionality had a positive influence on their autobiographical memory. Finally, the effect of children's emotion knowledge on their autobiographical memory was partially mediated by their negative emotionality. These findings provide a preliminary evidence that children's emotion knowledge and negative emotionality may predict their autobiographical memory.

• Annual Conference on Human and Language Technology
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• 1990.11a
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• pp.235-246
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• 1990

McClelland와 Rumelhart (1981)의 상호작용활성화 모형과 Feigembaum과 Simon (1984)의 초보지각자-기억자 모형 (Elementary Perceiver and Memorizer, EPAM)을 두 음절 한글단어에서의 낱자 지각을 중심으로 검증한 김 재갑과 김 정오 (1990)의 실험을 새 자극 단어들과 변수를 포함시킨 두 실험을 수행하였다. 여섯 낱자들로 구성된 단어의 둘째 음절위치에서 단어 내의 낱자들은 단독으로 제시되는 낱자들보다 더 부정확하게 파악되었고 (단어열등효과), 이 결과는 다섯 낱자로 된 두 음절 단어들에서는 관찰되지 않았고, 그 배후 기제는 세 낱자들로 구성된 단어의 부분에 대한 제한된 주의 용량의 배정임을 시사하는 결과를 얻었다. 본 연구의 결과들은 상호작용활성화 모형보다 EPAM 모형에 의해 더 잘 다루어짐이 밝혀졌다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.287-290
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• 2004

A structure using the two-way shape memory effect (TWSME) returns to its initial shape by increasing or decreasing temperature under initial residual stress. Through the thermo-mechanical constitutive equation of shape memory alloy(SMA) proposed by Lagoudas et al., we simulate the behavior of a double actuator in which two SMA wires are attached to the tip of panel under the initially given residual stress. Through the numerical results conducted in the present study, the proposed actuator device is suitable for repeated actuation. The simulation algorithm proposed in the present study can be applied extensively to the analysis of the assembled .system of SMA-actuator and host structure in the practical applications.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2010.05a
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• pp.25-30
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• 2010

자기설명이 학습을 촉진시키려면 무엇을 설명해야 하는지 판단해야 하고, 그에 대해 적절한 설명을 산출해내어야 한다. 본 연구에서는 촉진자극(propmpt)를 제공해서 무엇을 설명해야 하는지에 대해 도움을 주면 자기설명 효과가 얻어지는지 알아보았다. 또한 자기설명과 촉진 자극의 효과가 학습자의 인지욕구(need for cognition)와 상호작용하는지 알아보기 위해 인지욕구 수준을 상하로 나누어 3 요인 실험을 실시하였다. 촉진자극과 자기설명의 효과는 과제와 학습자의 인지욕구 수준에 따라 다르게 나타났다. 기억검사에서는 인지욕구가 낮은 학습자에게서만, 자기설명의 효과와 촉진자극의 효과가 관찰되었다. 반면에 이해검사에서는 인지욕구의주효과가 유의하였고, 3 요인상호작용 효과가 경향을 보였다. 즉 촉진 자극을 제공하는 것은 인지욕구가 높은 학습자에게서만 학습을 향상시켰다. 이 결과는 인지부하가 학습에 영향을 미치는 것으로 해석되었다.

• Science of Emotion and Sensibility
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• v.14 no.3
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• pp.371-384
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• 2011

Three experiments were carried out to examine how LED lighting hues influence to the rating and recognition of affective stimuli. In Experiment 1 and 2, IAPS affective pictures were used and an affective rating(valence and arousal) task and a recognition memory task were conducted under red, green, blue, and white hue LED lightings in Experiment 1 and cyan, magenta, yellow, and white ones in Experiment 2, respectively. In Experiment 3, affective words were used and the same two tasks were conducted under red, green, blue, and white hue LED lightings. According to the results of affective rating tasks, when primary hues(RGB) were used, red LED lighting elicited an excitement at the arousal dimension and green LED lighting evoked pleasantness at the valence one. When secondary hues(CMY) were used, magenta and cyan showed the similar but weaker patterns of responses comparing to red and green. The results of recognition memory task showed that the responses to the picture stimuli presented at green and cyan hue lightings tended to be a bit faster comparing to the stimuli presented at the other conditions but the difference was insignificant. In Experiment 3, however, recognition memory responses to the affective words presented at green hue lighting were faster significantly. These results indicate that warm colors like red and magenta elicit unpleasantness or excitement while cool colors like green and cyan evoke pleasantness or relaxation, and the primary hues provoke more positive or negative affectivity than secondary ones do. Particularly, the result of recognition memory task in Experiment 3 suggests that green hue LED lighting might be advantageous at the memory performance of language stimuli rather than visual ones.