• Steel and Composite Structures
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• v.17 no.6
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• pp.891-906
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• 2014

This study aims to present a three dimensional finite element model to investigate the wave propagation in a concrete filled steel tubular column (CFSC) due to transient impact load. Both the concrete and steel are regarded as linear elastic material. The impact load is simulated by a semi sinusoidal impulse. Besides the CFSC models, a concrete column (CC) model is established for comparing under the same loading condition. The propagation characteristics of the transient waves in CFSC are analyzed in detail. The results show that at the intial stage of the wave propagation, the velocity waves in CFSC are almost the same as those in CC before they arrive at the steel tube. When the waves reach the column side, the velocity responses of CFSC are different from those of CC and the difference is more and more obvious as the waves travel down along the column shaft. The travel distance of the wave front in CFSC is farther than that in CC at the same time. For different wave speeds in steel and concrete material, the wave front in CFSC presents an arch shape, the apex of which locates at the center of the column. Differently, the wave front in CC presents a plane surface. Three dimensional effects on top of CFSC are obvious, therefore, the peak value and arrival time of incident wave crests have great difference at different locations in the radial direction. High-frequency waves on the waveforms are observed. The time difference between incident and reflected wave peaks decreases significantly with r/R when r/R < 0.6, however, it almost keeps constant when $r/R{\geq}0.6$. The time duration between incident and reflected waves calculated by 3D FEM is approximately equal to that calculated by 1D wave theory when r/R is about 2/3.

• Journal of the Korean Society of Earth Science Education
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• v.17 no.1
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• pp.70-85
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• 2024

The purpose of this study was to find out what impact climate action has on study participants and why climate action education is difficult in high schools. For this purpose, a basic qualitative research method was selected, and the study participants were five middle school students at the time of the activity. The results of this study are as follows. Due to the climate action in middle school, the participants' career path changed specifically and their climate literacy was cultivated. And climate action education in high schools was not enough. Environmental subjects that provide climate action education were difficult to open because they were not chosen by many students, and it was unrealistic to provide climate action education during creative experiential activities due to the burden of college entrance exams. The discussion points of this study are as follows. Climate action needs to be encouraged among middle school students because it helps shape career paths and cultivate climate literacy. Additionally, because sustainability is important in climate action, there is a need to establish specialized courses in climate action education in the curriculum of elementary, middle, and high schools so that climate literacy can be maintained consistently.

• Korean Journal of Applied Biomechanics
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• v.23 no.2
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• pp.125-130
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• 2013

Although the electronic body protector has been officially adopted by the World Taekwondo Federation(WTF) in 2006, no scientific information is available about the reliability of its performance. The purpose of this study, therefore, was to investigate the relationship between the impact value of electronic body protector and the impact force of force platform. Male collegiate Taekwondo athletes([MCTA], n=21) and male collegiate Taekwondo students([MCTS], n=20) volunteered to participate in the study. Each subject performed the apchagi, dollyeochagi and dwichagi on the force platform and the electronic body protector. At the apchagi, it showed that MCTS(about 4,700 N) generated more maximum kick force than MCTA(about 3,900 N), but it expressed that MCTA(about 5,300 N) generated more maximum kicking force than MCTS(about 4,400 N) at the dwichagi. At the apchagi and the dwichagi, it indicated the high coefficient of correlation(over r=.8) which supports higher explanation force the relationship between the impact value of electronic body protector and the impact force of force platform, but there was no statistically significant difference at the dollyeochagi.

• East Asian mathematical journal
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• v.39 no.4
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• pp.393-417
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• 2023

STEAM education, which was introduced to address many of the issues raised in science and technology education, has had a profound impact on the field of education over the past 13 years. This study aims to systematically analyze the research trends of STEAM education integrated with mathematics from 2010 to 2022 and to provide implications for future STEAM education. To this end, 89 articles published in domestic KCI journals were collected and analyzed. The results showed that more than half of the STEAM studies were related to the development and application of STEAM programs. The next most frequent studies were related to current state and improvement oaf STEAM education, followed by curriculum and textbook analysis, and by teacher education and teacher competencies. Students' and teachers' perceptions and attitudes toward STEAM education were addressed in only a few papers.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.5
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• pp.153-164
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• 2016

It is critical for adolescents to foster self-efficacy, creativity, and adventurous spirit as well as plans for appropriate career path in order to become good members of society. During this adolescent period, newspapers will be a good learning material as they deliver various and timely information in refined language. In this paper, we analyzed the impact of NIE on development of self-efficacy, awareness of career path, and entrepreneurship through comparing adolescents who regularly read newspapers with those who do not. We came up with the following result after analysis of surveys (with a sample size of 283) that targeted middle school and higher grade elementary school students across Korea. We confirmed that reading newspapers has a positive impact on development of self-efficacy, awareness of career path, and entrepreneurship. More specifically, reading newspapers regularly has a positive impact on development of self-efficacy that subsequently has a positive impact on development of awareness of career path and entrepreneurship. Therefore, we found that simply reading newspapers regularly has a positive impact on development of self-efficacy, awareness of career path, and entrepreneurship with no special programs utilizing the newspapers. This is because various information and opinions in newspapers help adolescents to develop their own views, improve understanding and awareness of career, and development of sociality including creativity and adventurous spirit. There is the meaning as the first research that this research checks what the NIE of the adolescents affects the positive impact to not only the self-efficacy and career awareness but also entrepreneurship.

• Journal of Korean Society of Rural Planning
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• v.26 no.4
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• pp.81-91
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• 2020

This study was conducted to analyse climate change impact on agriculture infrastructure and propose improved measures on vulnerable areas. Recently, Climate change has resulted in damaging effects on agricultural fields through increases in drought intensity and flood risk. It is expected that this impact will increase over time. This study shows that Gyeong-gi and Chung-nam provinces are affected by drought and Gyeong-buk and Gyeong-nam provinces are affected by heavy rain. However, there are also regional variations within each province. Agricultural infrastructure affected by drought may also be affected by heavy rain. Increased damages on the infrastructure due to increased extreme weather events require preventive measures especially in vulnerable areas. In order to minimize the damage by climate change, we need to introduce a reform in the system which selects project region by analysing climate change impacts. Furthermore, impact assessment of climate change from projects such as 'water supply diversification', 'flooded farmland improvement', and 'irrigation facility reinforcement' also need to be adopted to improve the measures. The results of this study are expected to provide a foundation for establishing measures on coping with climate change in the agricultural sector.

• The Journal of the Korea Contents Association
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• v.17 no.5
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• pp.499-508
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• 2017

For analyzing the performance determinants of ODA projects in a technical and vocational education and training, this research analyzed the performance determinants of effectiveness representing the direct benefit and impact representing the long-term development effects of ODA project using FsQCA. As a result, the effectiveness of ODA project is achieved when relevance, sustainability and impact are high, or relevance, impact and efficiency are high. The impact of ODA project is achieved when relevance, sustainability and effectiveness are high, or relevance, effectiveness and efficiency are high. Two solutions for achieving effectiveness and two solutions for achieving impact show equifinality. The core factors for achieving effectiveness are relevance and impact, and the core factors for achieving impact are relevance and effectiveness. Also sustainability and efficiency are substitutability. A single causal variable can not have an effect on the ODA performance, but combined more than three causal variables can have an effect on the ODA performance. Therefore this research verified that collectives of causal variables rather than single causal variable should be considered to achieve the performance of ODA project in technical and vocational education and training.

• Proceedings of the Costume Culture Conference
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• 2006.09a
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• pp.81-84
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• 2006

• International Journal of Costume and Fashion
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• v.15 no.1
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• pp.87-101
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• 2015

From the 1920s to 1945, East Asia experienced radical social change with the introduction of new fashion styles, and new ways of thinking, from the West. The emergence of a new generation of "new women" educated in modern schools was part of this phenomenon, and functioned as a trend-setting influence in East Asian society. In schools, education in dressmaking, sewing, and home economics were important parts of female education. Adopting a new fashion style is, by necessity, accompanied by the new technology of dressmaking. Given that ready-made clothing was not generally available, dressmaking education also served to introduce a new material culture. In Korea and Taiwan under Japanese colonization, the greater part of school curricula and textbooks mirrored those in Japan, which enabled these countries to develop and adopt transnational styles as well as local styles. This research explores the transition of women's fashion in East Asia in modern and colonial conditions from the 1920s to the 1940s by analysing curricula and textbooks on dressmaking in comparison with the prevailing styles in each region. This is expected to suggest the impact of modernity in East Asia and the transnational styles of fashion in colonial Korea and Taiwan, as well as Japan, developed within the local culture. Colonial conditions are also discussed in terms of their impact and limitations in the transition of styles.

• Journal of the Korean Society of Earth Science Education
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• v.4 no.2
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• pp.89-101
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• 2011

Science, Mathematics, Engineering, and Technology (STEM) integrated education has been spotlighted as a new approach for promoting students' conceptual understanding and supporting their future career in STEM field. There is increasing evidence of the positive impact of using a whole design process that can be an example of STEM integrated activities to improve students' conceptual understanding and problem solving skills. However, there is a lack of information on how teachers should accomplish science and engineering integration activities in their classroom and what process they should pay attention. To answer this question, we research the relationship between an design process and students' conceptual understanding using an engineering design activity, called 'Save the Penguins', and study on how each step in an engineering design process in this activity enhance students' conceptual knowledge in science. We found that testing their prototypes and discussing with their peers were the most important process for students to understand and apply science concept for their design, even though the whole engineering design process (demonstration about radiation, discussion about examples in our lives, and testing and reviewing their prototypes, and making final design) helps the students understand the scientific concepts.