• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.4
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• pp.413-419
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• 2011

The nano-size hoenycomb structures have the higher ratio of the surface to the volume than macro-size honeycomb structures, and they can maximize the functionality of the electrical and chemical catalyst. The mechanical behaviors of the nano-sized structures are different from ones of the macro-size structure, and it is caused by the surface effect. This surface effect can be investigated by the atomistic simulation; however, the prediction of mechanical behaviors of the nano-sized honeycombs are practically impossible due to excessive computational resources and computation time. In this paper, by combining the bridging method considering the surface stress elasticity model with homogenization method, the mechanical behaviors of the nano-sized honeycombs are predicted efficiently.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.331-344
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• 1987

A numerical analysis has been conducted on the interaction of the thermal radiation and natural convection in a rectangular enclosure filled with a gray fluid. P-1 approximation is adopted for the radiative transfer and its application limit is examined. Considered are the Stark number effect, the optical thickness effect and the wall emissivity effect on the flow and heat transfer characteristics. As the Stark number increase or the optical thickness decreases, the boundary layer thickness and the flow velocity increase. Transition to turbulence is retarded with the increase of the radiation effect. When the optical thickness is one, the radiation effect is negligible for the Stark numbers larger than 10.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.251-256
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• 2020

Based on the development of SNS in Mobile and Internet, crisis management is regarded as an important issue that determines the rise and fall of businesses. This study aims to contribute to more efficient implementation of crisis management messages by examining the relationship between the strategy of crisis management communication and the level of specificity of the message. The study found that consumers evaluated the crisis-hit company's acceptance communication strategy to show a higher level of integrity, reliability and appropriateness than the defensive strategy. However, this main effect is mediated by the specificity (high specificity vs. low). Specifically, consumers' assessment of crisis management messages and information-seeking behavior were found to be most favorable when used in a mixture of acceptance strategies and high specificity. Conversely, the lowest effect was the combination of defense strategy and high specificity. Based on these results, the theoretical discussions is described for crisis management practitioners of enterprises and organizations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.455-464
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• 2013

If North Korea continuously remains an isolated nation without social interaction with South Korea, the gaps in the theoretical and technological status in construction technology become greater between North and South Korea. Therefore if interactions between North and South Korea can be made, there will be significant improvement in infrastructure technological performance can be made(i.e., Reinforced Concrete bridges). This study was performed to compare and analyze data related to the design standards of North Korean RC bridges and to execute a structural analysis based on standard design specifications of RC slab bridges. Especially, basic study of analyzing the influences on design truck loads of North and South Korea was conducted for the purpose of predicting the performance of North Korean RC slab bridges and the safety levels of traveling vehicles in advance. It is expected that the results of this study can be used as fundamental data for the set-up of South-North RC bridge specification when South and North Korea enter a stage of cooperation and interaction between South and North Korea are actively pursued to prepare for reunification.

• Journal of Elementary Mathematics Education in Korea
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• v.18 no.3
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• pp.399-424
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• 2014

Although teacher preparation programs are important for prospective teachers to build a foundation of teaching expertise, there has been lack of research in this area. This paper analyzed in what ways prospective teachers' ability in describing and commenting on elementary mathematics instruction has been changed while they were taking in the course of teaching elementary school mathematics. The results of this study showed that in late description the teachers tended to notice the core flow of a lesson and the use of instructional strategies appropriate to the mathematical content to be taught. They also tended to comment on instructional strategies and mathematical discourse from the teacher's perspective and evaluated them without alternative approaches. A noticeable change occurred in late comments wherein prospective teachers considered both the teacher and students, supported their comments by theories they had learned through the course, and interpreted the classroom events they had noticed. Building on these results, this paper closes with implications of teacher education programs to enhance prospective teachers' ability to analyze elementary mathematics lessons.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.113-122
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• 2013

The movie "Beautiful Mind" directed by Ron Howard is about a genius global mathematician, John Nash's life. In the movie, the main actor, John Nash is a schizophrenic patient who suffers from hallucination and delusion, and his illusion appears as three distinct characters. Each researcher has had a different opinion on the interpretation of these three characters, but many parts of their opinions are losing consistency. Especially the girl is assumed to be a character from the main actor's hallucination because she is ageless or there is no interpretation of the girl. Although the director Ron Howard did not adopt Aldous Huxley's theory "the more you know the more you see" for the movie, he analyzed the characters in the way of his own with thinking that he can analyze them in accordance with the knowledge level of audience. The imaginary characters come out from John Nash's head and who he wants to be. They are the basic human needs, earthly desire, sexual desire and the desire for honor. John Nash minutely reflects these three kinds of desires in an imaginary world through the three characters. This thesis is to newly suggest the symbolic meaning of the imaginary characters in the movie by clearly analyzing the meaning of the controversial three characters.

• Journal of the Korean Geotechnical Society
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• v.18 no.2
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• pp.161-170
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• 2002

This paper describes a systematic way of simultaneously identifying the ambient pore pressure and the rigidity index $(=G/s_u)$ of soil by applying an optimization technique to the early part of piezocone dissipation test result. An analytical solution developed by Randolph & Wroth(1979) was implemented in normalized from to express the build-up and dissipation of excess pore pressures around a piezocone as a function of the rigidity index. An ambient pore pressure and optimal rigidity index were determined by minimizing the differences between theoretical and measured excess pore pressure curves using optimization technique. The effectiveness of the proposed back-analysis method was examined against the well-documented performance of piezocone dissipation tests(Tanaka & Sakagami, 1989), from the viewpoints of proper determination of selected target parameters and saving of test duration. It is shown that the proposed back-analysis method can evaluate properly the ambient pore pressure and the rigidity index by using only the early phase of the dissipation test data. Also, it is shown that the proposed back-analysis method permits the horizontal coefficient of consolidation to be identified rationally. Consideration for strain level of back-analyzed rigidity index shows that it corresponds to at least intermediate to large strain level.

• Journal of Science and Technology Studies
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• v.4 no.2 s.8
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• pp.67-101
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• 2004

Although the study of citation patterns is an important theme within the sociology of science, due to the fact that it is intimately related to the production, reproduction, and evaluation of knowledge, only sustained theoretical research outlining the differences of citation patterns between the hard and soft sciences has been conducted, and empirical studies nevertheless remain few and far between. The perspectives of institutionalism and constructivism have to attempted to explain different citation patterns between the hard and soft sciences as a contrast between 'what one says' and 'who one is'. Therefore, against this background this study examines the 'theoretical' controversy empirically by comparing the contrasting citation patterns of physics, as a representative of hard science, and sociology, as a representative of soft science. The results, in brief, are as follows: the citaton patterns in physics, as in sociology, vary according to the author's status within the hierarchical employment structure, i. e. whether s/he is a full-time lecturer or not, but diversity of citation patterns according to Ph. D. diploma area is unique to sociology. These results would suggest that the explanation of constructivism is more relevant in explaining variance according to the author's status in the employment hierarchy, but the approach of institutionalism is more appropriate to understanding variance due to Ph. D. diploma area. Furthermore, this implies the complex diversity of the citation patterns between the hard and soft sciences, pointing us to the more qualified conclusion that rather than having to choose between institutionalism and constructivism according to a mutually exclusive either/or logic, these two approaches can in fact be mutually complementary, and these approaches should also be applied piecemeal to different levels of phenomena. In conclusion, this comparative research enables us to assert the following two claims: firstly that physics, as a 'science in society', produces knowledge dependent on social context, and secondly that it also possesses a characteristic that transcends locality from the view of a sociology of knowledge.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.593-602
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• 2018

This study examined the impact of trivial baselines obtained from GNSS single-baseline processing into a network adjustment in terms of accuracy and estimated coordinates sets. To this end, depending on the inclusion of the dependent baselines, three different types of experimental GNSS networks were composed and adjusted. The results showed that the networks including the trivial baselines are generally overestimated, but differences in the derived coordinates are limited at the millimeter level. A comparison of the adjusted coordinates with those published by the national geodetic agency showed that results of the network consisting of only the independent baselines are more constant than those of the networks with trivial baselines. Finally, a trivial baseline should be excluded from the GNSS network adjustment with a consideration of the realistic accuracy presentation and data processing burden.

• The Journal of Korean Institute for Practical Engineering Education
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• v.2 no.2
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• pp.55-60
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• 2010

We usually encounter Electro-magnetics phenomenons and only feel some part of that, but it is hard to feel it visually. Moreover understanding physically and quantitatively is not a easy work. These electrostatic field theory, magnetostatic field theory and interchange magnetic field theory combined with electromagnetic field are formulated experimentally and theoretically by James Clerk Maxwell in 1873. Electromagnetic field takes electro-magnetic phenomenons as a expansion of formula originated in Maxwell equations. Since this is based on expansion of formula, it is hard to understand for many students not only middle school and high school students learning it at the first time but also college students studying physics as a elementary class and even majors in electromagnetic field. The program is developed as a visual aid to cope with these problems, and even to deal with complex problem to estimate solution using numerical method.