• Journal of the Korean Society of Industry Convergence
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• v.3 no.4
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• pp.329-336
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• 2000

A geometric and material nonlinear finite element analysis is developed for the layered elastomeric bearings. In this study, a mixed variational approach with separate variables is used to describe the displacement and volume change of rubber. To represent finely deformed behavior, Kirchoff stress tensors are used and converted Eulerian stress tensors to describe real physical meanings. Newton's method is utilized to solve the governing nonlinear finite element equations. Numerical test are performed in the case of compression and shear to verify the theory and to illustrate the application of this analysis. And the results of this study were compared to the results of Moore's discrete finite element analysis.

• International journal of advanced smart convergence
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• v.8 no.2
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• pp.1-7
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• 2019

Drones will evolve from military to personal or social purposes. How can people socially interact with a drone that is familiar to them? This study explored the social proximity of human drone interaction with safety glass wall between participants and drone. The experiment results showed that drone's altitude, size and gender factor did not significantly affect social proxemics as to what extent participants got closer to hovering drones by the limitation of the distance from the safety wall. However, it shows a tendency that participants more closely approached an eye-level drone compared with an overhead drone, and females tended to approach more closely males. This study consequently demonstrated that most participants are nearly ready to allow a near field operation of social drone under safe conditions.

• Educational Technology International
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• v.22 no.2
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• pp.199-225
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• 2021

The aim of the current study was to suggest priorities needed to be considered by university instructors when designing online learning. Based on three types of interactions (learner-content, learner-instructor, and learner-learner interactions) for effective online learning (Moore, 1989), draft questionnaires representing each type of interaction were written. After examining content validity by two Ph.D. experts, the survey was constructed with an Importance-Performance Analysis (IPA) form. Data of 133 university instructors were collected online. Results showed that support for designing learner-learner interaction was the priority for improving online learning. In terms of learner-instructor interaction, instructors needed to provide social-emotional support to learners so that learners could have a sense of belonging. For learner-instructor interaction, supporting instructors to monitor the level of understanding was the most highly demanding strategy for online learning. Limitations and suggestions for further studies were discussed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.5
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• pp.77-85
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• 2002

Kaolin has long been used in aqueous coatings to produce high-quality coated paper products. While the kaolin industry hat always focused on innovation. the rate of new product introduction hat never been greater than in the past five-to-eight years due to the cost, quality and other competitive pressure facing papermakers. After summarizing many of the performance benefits offered by the new generation of kaolin-baled pigments. this paper reviews four specific pigment advances: a high-performance. ultrafine glossing pigment; an engineered pigment with a narrow particle size distribution; two products from a kaolin-based pigment family developed for metered size presses ; and a novel class of inkjet pigments.

• Korean Journal of Plant Taxonomy
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• v.53 no.1
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• pp.69-77
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• 2023

Leuzea chinensis (S. Moore) Susanna (Asteraceae), a previously unrecorded species in Korea, was found in Yeongdeok-gun, Gyeongsangbuk-do. Symplocos nakaharae (Hayata) Masam. (Symplocaceae), which had been recorded in the literature but whose native habitat was yet to be identified, was found in Geojedo Island, Gyeongsangnam-do. It was confirmed that Epilobium parviflorum Schreb. (Onagraceae) grew naturally on the islands of Jeollanam-do. Detailed morphological descriptions and geographical distribution of the three taxa are provided.

• Advances in nano research
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• v.15 no.4
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• pp.305-313
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• 2023

This study is aimed to investigate the electrically conductive properties of epoxy nanocomposites exposed to an acidic environment under various mechanical loads. For simultaneous assessment of the acidic environment and mechanical load on the electrical conductivity of the samples, the samples with and without carbon nanotubes were exposed to the acidic environment under three different loading conditions for 20 days. Then, the aged samples' strength and flexural stiffness degradation under crude oil and bending stress were measured using a three-point flexural test. The aged samples in the acidic environment and under 80 percent of their intact ultimate strength revealed a 9% and 26% reduction of their electrical conductivity for samples with and without CNTs, respectively. The presence of nanoparticles declined flexural stiffness by about 16.39%. Scanning electron microscopy (SEM) images of the specimen were used to evaluate the dispersion quality of CNTs. The results of this study can be exploited in constructing conductive composite electrodes to be used in petroleum environments such as crude oil electrostatic tanks.

• Journal for History of Mathematics
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• v.22 no.2
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• pp.27-52
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• 2009

This article discusses the contributions of the leader Oswald Veblen, who was the president of AMS during 1923-1924. In 2006, Korea ranked 12th in SCIE publications in mathematics, more than doubling its publications in less than 10 years, a successful model for a country with relatively short history of modern mathematical research. Now there are 192 four-year universities in Korea. Some 42 of these universities have Ph.D. granting graduate programs in mathematics and/or mathematical education in Korea. Rapid growth is observed over a broad spectrum including a phenomenal performance surge in International Mathematical Olympiad. Western mathematics was first introduced in Korea in the 17th century, but real significant mathematical contributions by Korean mathematicians in modern mathematics were not much known yet to the world. Surprisingly there is no Korean mathematician who could be found in MaC Tutor History Birthplace Map. We are at the time, to have a clear vision and leadership for the 21st century. Even with the above achievement, Korean mathematical community has had obstacles in funding. Many people thinks that mathematical research can be done without funding rather unlike other science subjects, even though they agree fundamental mathematical research is very important. We found that the experience of early American mathematical community can help us to give a vision and role model for Korean mathematical community. When we read the AMS Notice article 'The Vision, Insight, and Influence of Oswald Veblen' by Steve Batterson, it answers many of our questions on the development of American mathematics in early 20th century. We would like to share the story and analyze its meaning for the development of Korean Mathematics of 21st century.

• Journal of Korea Entertainment Industry Association
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• v.15 no.8
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• pp.91-106
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• 2021

The purpose of this study is to define the process of leading to self-realization and social solidarity through the process of contents planning, production, and distribution as Contents Activism, and to categorize specific execution steps. Based on this, we try to analyze concrete cases to find out the social meaning and effect of the practice of Contents Activism. As for the research method, after examining the differences between traditional activism and Contents Activism through a review of previous studies, the implementation process of Contents Activism was categorized into 7 steps. By applying this model, this study analyzed two cases of Contents Activism. The first case is the 100 laps challenge in the backyard planned by an elderly man ahead of his 100th birthday in early 2020, when the fear of COVID-19 spread. Sir Tom Moore, who lives in the UK, challenged to walk 100 laps in the backyard to help medical staff from the National Health Service as COVID-19 infections and deaths increased due to a lack of protective equipment. His challenge, which is difficult to walk without assistive devices due to cancer surgery and fall aftereffects, drew sympathy and participation from many people, leading to global solidarity. The second case analyzes the case of 'The Unfreedom of Expression, Afterwards' by Kim Seo-kyung and Kim Woon-seong, who were invited to the 2019 Aichi Triennale special exhibition in Japan. The 'Unfreedom of Expression, After' exhibition was a project to display the Statue of Peace and the lives of comfort women in the Japanese military, but it was withdrawn after three days of war due to threats and attacks from the far-right forces. Overseas artists who heard this news resisted the Triennale's decision, took and shared photos in the same pose as the Statue of Peace on social media such as Twitter and Instagram, empathizing with the historical significance of the Statue of Peace. Activism, which began with artists, has expanded through social media to the homes, workplaces, and streets of ordinary citizens living in various regions. The two cases can be said to be Contents Activism that led to social practice while solidifying and communicating with someone through contents.

• Journal of Christian Education in Korea
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• v.68
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• pp.345-374
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• 2021

This study is a paper which studies the fact that autobiographical writing in Christian educational books is an important channel for studying the identity of Christian educators. The identity of Christian educators is the background and foundation of the study of Christian education theory. It was found through research that the scholar's identity is more evident in autobiographical writing from a first-person perspective experienced by the author than in argumentative writing with objective and cognitive limitations. This study examined the concept and characteristics of autobiographical writing research, the relationship of autobiographical writing research and self-identity, the relationship between autobiographical writing and Christian education, and discovered autobiographical writing in Christian educational scholars' books. Through the autobiographical writing of Maria Harris' Teaching and Religious Imagination, Parker Palmer's The Courage to Teach, and Elizabeth Moore's Teaching as a Sacrament Act, we studied that the identity of Christian educators can meet, transform, and expand learners' identity as well. Through research, it has been confirmed that autobiographical writing takes the form of a story, but as a story distinct from the story, it becomes a place where the authors' identity and readers' identity can meet, wrestle and expand. Autobiographical writing has a relationship with story and self-identity. These characteristics are also linked to Christian educational goals that focus on the formation and transformation of self-identity. The autobiographical writing in Harris, Palmer, and Moore's writings shows the identity of a teacher, including scholars' theological perspectives and views on education. As the writing of Christian education books so far has become argumentative and objective writing, readers has felt a sense of disparity and disconnection. If autobiographical writing becomes educational books' style, it can invite readers to empathize with who the author is. Christian education will experience more fundamental changes with autobiographical writing.

• Korean Journal of Environment and Ecology
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• v.25 no.6
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• pp.819-827
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• 2011

Climate change is recognised as the best serious environmental problem in recent time, and high alpine or high latitudinal organisms especially endangered by its change. Leontice microrhyncha is recorded one of the endangered species by the Ministry of Environment Korea. We surveyed ten L. microrhyncha populations distributed at Taebaek Mountains, high mountain area in Kangwon province. L. microrhyncha is distributed 940m~1350m high altitude which equivalent of Warmth Index $53^{\circ}C{\cdot}month$ to $75^{\circ}C{\cdot}month$, the range of conspicuous cool temperate forest zone. The plant species distributed at slope of $5^{\circ}{\sim}23^{\circ}$ on northeast slopes. The vegetation structure at tree layer of L. microrhyncha distribution area is dominated by Quercus mongolica, Betula costata, Cornus controversa, Acer mono in tree layer, and by Staphylea bumalda, Deutzia glabrata, Stephanandra incisa in shrub layer. The species diversity of herb layer of each L. microrhyncha population showed from 0.21 to 0.98, and the importance value of L. microrhyncha in each population was the highest at blooming time of L. microrhyncha. These results will provide the basic information for the development of conservation strategies for this endangered species.