• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.277-280
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• 2001

The effects of a -phase morphology on the static and dynamic deformation behavior of a Ti-6Al-4V alloy was investigated in this study. Static tension test, static and dynamic tension test and hot compression test were conducted on three microstructures of Ti-6Al-4V alloy, i.e., equiaxed, widmanstatten and bimodal microstructures. Fracture surfaces of all three microstructures represented ductile fracture appearance, though the formation of adiabatic shear bands was noticed at dynamic torsion test. The susceptibility of forming adiabatic shear bands was greatest in the equiaxed microsoucture and lowest in the bimodal microstructure, which was evidenced by hot compression test.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1151-1152
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• 2006

In this paper, we examined 10 domestic samples of three different model using thermal, humidity freeze, thermal-endurance and damp heat test under IEC61215 photovoltaic module environmental endurance test condition. Three was almost no changes on power generation. Insulation resistance capacity was much higher than judgement standard but, showed unstable results depending on environmental test items. On external appearance test, there were two models which showed bubble, humidity penetration, seal melted frame phenomenon. From this results, the degree of aging under the external environment is a main cause that shortens photovoltaic module life time. So it is considered that the efforts for finding optimum condition of manufacturing process should be needed.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.267-274
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• 2021

본 연구는 동영상 학습에서 교수자 출연 여부와 교수자 발화속도가 학습몰입과 교수실재감의 효과에 차이를 나타내는지를 실험을 통해 밝히는 것이다. 실험 대상자는 중국 형태대학교 1학년 183명이며, 이들에게 교수자가 출연여부와 발화속도 고저의 4가지 동영상을 학습하도록 한 후, 학습몰입과 교수실재감을 측정하였다. 수집된 자료는 다변량분산분석을 통해 분석하였다. 분석결과 첫째, 교수자가 출연한 동영상을 학습한 집단이 그렇지 않은 집단보다 학습몰입과 교수실재감이 모두 높게 나타났다. 둘째, 교수자의 발화속도가 높은 동영상으로 학습한 집단이 낮은 동영상으로 학습한 집단보다 학습몰입과 교수실재감이 모두 높게 나타났다. 셋째, 교수자 출연여부와 발화속도의 학습몰입과 교수실재감에 대한 상호작용 효과는 유의한 차이가 없는 것으로 나타났다. 이러한 연구결과는 대학 수업에서 효과적인 학습을 위한 강의 동영상을 개발할 때 교수자의 출연여부와 발화속도를 어떻게 설계할 것인지에 대한 이론적·실천적 근거를 제공한다. 즉 가급적 동영상에 교수자가 출연하여 표정, 몸짓과 같은 비언어적 방식으로 사회적 단서를 제시하는 것이 중요하다. 또한 교수자는 동영상에서 약간 빠른 속도로 설명함으로써 학생이 학습에 더 집중하여 몰입하게 할 수 있다. 교수자 출연과 빠른 발화속도는 학습에 몰입하게 하고, 동영상에서 교수행위가 실재로 이루어지고 있다는 느낌을 주게 한다는 것을 시사한다.

• Journal of Advanced Marine Engineering and Technology
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• 제33권4호
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• pp.517-523
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• 2009

Magnesium alloys have many advantages such as a low density, high strength/weight ratio and well recycle. And joining process is absolutely necessary to expand the field of application of magnesium alloy. The main problems of conventional process such as arc welding for magnesium alloy are the inflammability, a tendency toward crack formation and the appearance of porosity during solidification. Laser welding technology is a promising means for overcoming these difficulties. This study is related to the laser weldability of AZ31 magnesium alloy, an all-purpose wrought alloy with good strength and ductility. The effect of welding conditions on the weldability of butt joints was examined. Also, the mechanical properties of butt welded joints were investigated by tensile test and hardness test.

• Wind and Structures
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• 제25권4호
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• pp.361-379
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• 2017

In view of the importance of the wind-structure interaction for tall and slender structures, an aeroelastic model test of the 610m-high TV tower with a complex and unique structural configuration and appearance carried out successfully. The assembled aeroelastic model of the TV tower with complex shape and structure was designed and made to ensure the similarities of the major natural frequencies and the corresponding mode shapes. The simulation of the atmospheric boundary layer with higher turbulent intensity is presented. Since the displacement and acceleration responses at several measurement sections were directly measured in the wind tunnel test, a multi-mode approach was presented to indirectly estimate the displacement and acceleration responses at arbitrary structural floors based on the measured ones. It can be seen that it is remarkable for the displacement and acceleration responses of the TV tower in the two horizontal directions under wind loads and is small for the dynamic response of the torsional displacement and acceleration.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.674-679
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• 2004

In this study, we investigated the cause analysis on fracture of diesel locomotive engine liner, which was trouble assuming the inflow of cooling water. In order to reveal the cause of fracture, we studied the use history of engine, the drawing of production appearance and the stress distribution of engine in use. Also, we conducted experiments such as tension strength test, bending test and hardness test. Next, we observed fractured sections by SEM for the purposed of explaining the fracture mechanism of engine liner. Test results showed that fracture mechanism was brittle fracture due to coarse casting structure and stress concentration caused by manufacturing badness.

• 복식
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• 제59권9호
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• pp.16-25
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• 2009

The purpose of this study is to develop pattern of a Upper Garment Prototype for late elementary school aged girls. The body of late elementary school aged girls changes steadily up to the adult and is characterized by its periodic noticeable physical distinctions. This study is selected a test pattern from 3 existing patterns through a preliminary wearing test, conducted wearing tests, and sensory evaluations three times to review and improve the pattern, and presented the pattern of late elementary school aged girls. The research pattern was developed considering aesthetic and functional aspect. The average score of sensory evaluation on appearance was 4.13 for the research pattern, which was higher than 2.74 for the test pattern. The according to the results of verifying significant differences in the test items between the two patterns through the t-test, in the items such as pleats in the line of a waist, the ease of the girth of a waist, the location of shoulder line was superior to the test pattern. The average score of the sensory evaluation on functionality was 4.91 for the research pattern, which was higher than 3.90 for the test pattern. The research pattern is superior to the test pattern in static posture, dynamic posture than the test pattern.

• 한국가정과교육학회지
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• 제27권3호
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• pp.47-61
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• 2015

본 연구는 중학생의 외모관리행동에 따른 바른 인성과 창의적 인성의 차이를 살펴봄으로써 외모관리행동에 따른 바른 인성과 창의적 인성 측면에서 어떤 점들을 고려할 수 있을지에 관한 기초적인 자료를 제공하는데 그 목적이 있다. 따라서 본 연구의 목적을 위해 광주광역시에 소재한 중학교 3학년 600명을 대상으로 2014년 2월 3일부터 2월 14일까지 설문지조사를 실시하였고 544부를 최종분석에 사용하였다. 자료 분석을 위해서 SPSS/PC WIN 19.0 프로그램을 사용하여 기술통계, 요인분석, 신뢰도 분석(Cronbach's ${\alpha}$), 일원분산분석(One-way ANOVA), Duncan-test를 실시하였다. 이와 같은 연구 결과를 살펴볼 때 외모관리행동 중 토털코디네이션 추구행동은 중학생의 관심도가 높고 바른 인성과 창의적 인성과 관련이 깊었다. 바른 인성에서는 기본생활습관과 효도 경애, 창의적 인성에서는 호기심, 사고의 개방성, 위험감수, 과제집착, 심미성에 긍정적인 결과를 보였다. 이러한 점을 고려하여 가정 교과 교육과정에 토털코디네이션 추구행동과 관련된 내용이 보완될 필요성이 있다고 생각된다. 또한, 의생활 영역과 관련된 방과 후 활동 프로그램을 실시하거나 자유학기제를 통한 진로탐색의 기회를 마련하여 토털코디네이션과 관련된 심층적인 교육이 이루어진다면 바른 인성과 창의적 인성에 긍정적인 영향을 미칠 것이라 기대한다.

• 한국산학기술학회논문지
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• 제13권11호
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• pp.5292-5298
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• 2012

본 연구는 이동 중 구급차에서 응급구조사의 삽관자세 변화에 따른 시야의 높이 변화가 기관내 삽관의 신속성에 영향을 미치는지 비교하고 환자의 삽관자세 변화가 기관내 삽관의 신속성에 영향을 미치는지 분석하여 심정지 및 외상성 응급 환자에게 효과적인 전문기도관리를 시행하는데 목적이 있다. 연구대상은 C도 13개 소방서에 근무하고 있는 1급 응급구조사 60(대조군30명, 실험군30명)명을 편의추출하여 시행하였으며, 자료 분석은 SPSS WIN 14.0 Version을 사용하여 하였다. 연구결과 전문기도관리의 신속성 향상을 위해서는 환자의 냄새맡기 자세와 주들것과 응급구조사 시트 사이 공간에서의 기관내 삽관이 효과적일 것으로 사료되고 실험 후의 삽관 자신감이 유의하게 상승 하였으므로 전문기도관리의 효율성 향상을 위해서는 구급차 내에서의 삽관자세와 방법에 대한 지속적인 교육(훈련)이 필요할 것으로 사료된다.

• 패션비즈니스
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• 제11권4호
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• pp.29-41
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• 2007

This study is to research how women aging from 20 through 40 Apperance -Mnagement Bhavior and care of their outer looks from a beauty treatment perspective. This research should help satisfy the wants of women who are the main clients of the beauty products and help the beauty industry to produce new products and also to help out on their marketing strategy. In order to search the general characteristics of our target women, Frequency Analysis was used, to find out the sub-factor of interest in beauty Factor Analysis and Reliability Analysis was used. In order to divide the group according to Degree of Apperance Concern 'sub-factor, cluster analysis, analysis of variance, Scheffe'-test, $X^2-test$ was used, and to find out the difference on how they care of beauty analysis of variance was used, and further more to summarize the result of analysis of variance Scheffe'-test was used. As a result, in all different ways of beauty caring, weight resisting, skin care and plastic surgery summed up similarly among the self-care group, hair care ended up with similar results among all three groups: self-caring group, no interest in beauty at all group, and the too conscious of other eyes group, and results on the interest rate of clothing ended up similarly among the other-eye conscious group, beauty care interest group, and the self-care group.