• Structural Engineering and Mechanics
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• 제70권4호
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• pp.467-477
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• 2019

The objective of this work is to analyze by traction tests, the mechanical behavior of an assembly of type metal / metal by various assembly processes; bonding, riveting and hybrid, on the one hand to show the advantage of a hybrid assembly with respect to the other processes, and on the other hand, to analyze by the finite element method the distribution of the stresses in the various components of the structure and to demonstrate the effectiveness of the use of a hybrid assembly with respect to other processes. The number of rivets has been considered. The results show clearly that the value of the different stresses is reduced in the case of a hybrid junction and that the number of rivets in an assembly can be reduced by using a hybrid joint.

• Advances in materials Research
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• 제11권1호
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• pp.1-22
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• 2022

In this paper, the nonlocal integral Timoshenko beam model is employed to study the free vibration characteristics of singled walled carbon nanotubes (SWCNTs) including the thermal effect. Based on the nonlocal continuum theory, the governing equations of motion are formulated by considering thermal effect. The influences of small scale parameter, the chirality of SWCNTs, the vibrational mode number, the aspect ratio of SWCNTs and temperature changes on the thermal vibration properties of single-walled nanotubes are examined and discussed. Results indicate significant dependence of natural frequencies on the nonlocal parameter, the temperature change, the aspect ratio and the chirality of SWCNTs. This work should be useful reference for the application and the design of nanoelectronics and nanoelectromechanical devices that make use of the thermal vibration properties of SWCNTs.

• 대한물리치료과학회지
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• 제30권4호
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• pp.1-8
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• 2023

Background: This study evaluates the usability of the Motion-Tracking Gait Assistive Walker (MTGAW) designed for elderly individuals and those with disabilities, identifying areas for improvement through interviews with physical and occupational therapists. Design: A survey study involves the usability test for MTGAW. Methods: Usability evaluations were conducted with 37 physical therapists and occupational therapists. The process included explanation, product usage, satisfaction surveys, and interviews. A satisfaction survey covering 19 items across safety, maneuverability, usability, and management areas was administered. Individual interviews identified areas for improvement. Results: Overall, high satisfaction was reported across the four areas, but interviews highlighted the need for improvements, such as addressing discomfort due to slow speed and enhancing safety measures to prevent rear-end falls. Adjusting the walker's height and width to suit the user's physique was also suggested. Conclusion: MTGAW enhances walking support and hand movement freedom but needs refinement in speed control, fall prevention, and customization based on the user physique. Future efforts should focus on developing an improved MTGAW, considering recommendations from physical therapy experts, and conducting studies to analyze its clinical effectiveness for commercialization.

• Corrosion Science and Technology
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• 제22권5호
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• pp.314-321
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• 2023

The aim of the present study was to investigate the effect of thymus extract on corrosion inhibition of aluminum 5083 alloy in a 0.1 M NaCl medium prepared using a mixture of ethylene glycol and water using potentiodynamic and electrochemical impedance spectroscopy (EIS) techniques. The potentiodynamic electrochemical technique showed an increase in corrosion inhibition efficiency starting from 49.63% at a concentration of 0.25 g/L to 92.71% at a maximum concentration of 1.25 g/L of the extract. These results were consistent with those obtained via EIS analysis. Spectral characterization of the tested plant extract using the Fourier-transform infrared spectroscopy (FTIR) technique confirmed the presence of organic compounds having different oxygen and aromatic functionalities in the extract that could help enhance the adsorption of these compounds on the aluminum surface. This study reveals possible adsorption isotherm of the thymus extract on the aluminum surface, supporting a Langmuir isotherm for the adsorption of inhibitor molecules on this surface.

• 한국응용과학기술학회지
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• 제37권3호
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• pp.594-603
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• 2020

본 연구는 비만아동의 골격성숙도가 정상 아동들 보다 높고 성조숙증으로 이어질 확률이 높은 것을 문제점으로 삼아 비만아동의 골격성숙도에 따른 체격 및 체력의 관계를 규명함으로써 비만아동의 건강증진에 기여하는 것을 목적으로 하였다. 연구대상은 10세부터 13세의 비만아동 총 243명을 대상으로 생물학적 성숙지표를 나타내는 골격성숙도는 X-ray 촬영 후 TW3 방법을 이용하여 평가하였고, 골격성숙도에 따른 미숙집단(n=70), 보통집단(n=128), 조숙집단(n=45)으로 나누었다. 체격은 신장계, InBody 270(Biospace, Korea)을 이용하여 3개 항목을 측정하였다. 체력측정은 총 7개 항목으로 근력, 근지구력, 유연성, 순발력, 심폐지구력, 평형성, 민첩성을 측정하였다. 자료처리는 SPSS 25.0을 사용하여 기술통계, 일원변량분석(ANOVA)을 실시하였고, 사후검정은 Duncan's multiple range 방법을 이용하였으며, P< .05 수준에서 유의한 것으로 간주하였다. 본 연구의 결과는 다음과 같다. 첫째, 골격성숙도에 따른 신장과 체중의 체격 요인에서 남자와 여자 미숙집단, 보통집단, 조숙집단 간 통계적으로 매우 유의한 차이를 보였다. 둘째, 골격성숙도에 따른 체력 비교에서 남자의 경우 근력, 순발력, 민첩성에서 유의한 차이가 나타났으며, 여자의 경우 근력, 평형성에서 유의한 차이가 나타났다.

• 생명과학회지
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• 제18권7호
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• pp.986-991
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• 2008

본 연구는 남자초등학교 4학년생 중 태권도 유품자($1{\sim}2$품)로서 태권도칼슘섭취군(8명), 태권도군(8명), 대조군(8명) 총 24명을 대상으로 하였다. 태권도와 칼슘 섭취가 남자초등학생의 체격, 성장호르몬 및 IGF-1에 미치는 영향을 규명하기 위하여 운동 강도 RPE ($7{\sim}15$), 운동빈도 주 5회, 1회 50분의 지속시간으로 12주간 실시하였다. 칼슘은 1일 1회 저녁에 750 mg을 섭취시킨 결과 다음과 같은 결론을 얻었다. 신장은 집단 내 세 그룹 모두 유의하게 증가하였지만 집단 간에서는 대조군에 비해 태권도군과 태권도칼슘섭취군이 유의하게 증가하였다. 성장호르몬은 대조군이 유의하게 감소하였으며 태권도군과 태권도칼슘섭취군은 대조군에 비해 유의하게 증가하였다. IGF-1은 집단 내 태권도군과 태권도칼슘섭취군이 유의하게 증가하였으며 집단 간에서는 대조군에 비해 태권도군과 태권도칼슘섭취군이 유의하게 증가하였다. 이상의 결과를 통해 초등학생에게 태권도프로그램과 칼슘섭취는 신장과 체중, 성장호르몬 및 IGF-1에 긍정적인 영향을 미쳤으며, 향후 적절한 태권도프로그램개발과 운동처방 및 영양섭취에 대한 지속적인 연구가 요구된다.

• Kyungpook Mathematical Journal
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• 제46권3호
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• pp.367-376
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• 2006

We investigate semi-symmetry and pseudo-symmetry of some 3-dimensional Riemannian manifolds: the D'Atri spaces, the Thurston geometries as well as the ${\eta}$-Einstein manifolds. We prove that all these manifolds are pseudo-symmetric and that many of them are not semi-symmetric.

• Journal of Nutrition and Health
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• 제22권3호
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• pp.194-208
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• 1989

This is an analysis of the study on dietary intake and anthropmetric measurement of Koreans in the latter part of 19th century. This study attempts to compare the 1895 study and the dietary intake of Korean in the subsequent hundred years. This study also examines the dietary effect on the physique and health status of Korean Men.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.50-55
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• 2003

In this paper, we describe and review the main techniques which are currently being used or studied, in order to synthesise thin films of device-worthy polycrystalline silicon material (poly-Si) on glass or other non-refractory large area substrates. The problems and limitations of the excimer laser processing are first emphasised and some novel or revisited crystallisation processes with good potential for industrialisation are subsequently presented and discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.97-100
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• 2005

The recent Bistable Nematic ($BiNem{(R)}$) LCD technology presents long term bistability, high level passive matrix multiplexing and high optical quality. The BiNem device, based on anchoring breaking, needs specific low anchoring strength materials - alignment layers and liquid crystal mixtures. We present here our approach to develop nematic mixtures with wide enough temperature range and low zenithal anchoring energy.