• Advances in aircraft and spacecraft science
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• v.8 no.4
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• pp.345-372
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• 2021

The analysis of nonlinear vibrations, buckling, post-buckling, flutter boundary determination and post-flutter behavior of a homogeneous curved plate assuming cylindrical bending is conducted in this article. Other assumptions include simply-supported boundary conditions, supersonic aerodynamic flow at the top of the plate, constant pressure conditions below the plate, non-viscous flow model (using first- and third-order piston theory), nonlinear structural model with large deformations, and application of mechanical and thermal loads on the curved plate. The analysis is performed with constant environmental indicators (flow density, heat, Reynolds number and Mach number). The material properties (i.e., coefficient of thermal expansion and modulus of elasticity) are temperature-dependent. The equations are derived using the principle of virtual displacement. Furthermore, based on the definitions of virtual work, the potential and kinetic energy of the final relations in the integral form, and the governing nonlinear differential equations are obtained after fractional integration. This problem is solved using two approaches. The frequency analysis and flutter are studied in the first approach by transferring the handle of ordinary differential equations to the state space, calculating the system Jacobin matrix and analyzing the eigenvalue to determine the instability conditions. The second approach discusses the nonlinear frequency analysis and nonlinear flutter using the semi-analytical solution of governing differential equations based on the weighted residual method. The partial differential equations are converted to ordinary differential equations, after which they are solved based on the Runge-Kutta fourth- and fifth-order methods. The comparison between the results of frequency and flutter analysis of curved plate is linearly and nonlinearly performed for the first time. The results show that the plate curvature has a profound impact on the instability boundary of the plate under supersonic aerodynamic loading. The flutter boundary decreases with growing thermal load and increases with growing curvature.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.1-10
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• 2023

The purpose of this study is to explore ways to nurture creative and fusion-type talents centered on ANT. In order to nurture creative and convergence-type talents centered on ANT, first, it is necessary to utilize Kao's Law in the network formation stage. Second, it is necessary to utilize the strong power of weak ties in the network formation stage. Third, in order to cause a stir in the stage of raising questions among the four stages of translation, the ability to ask questions must be developed. Fourth, education in various creative problem-solving techniques is needed to throw a stir. Fifth, in order to successfully intervene in the second stage of the four stages of translation, the stage of attracting attention, communication and critical thinking skills must be trained. Suggestions for follow-up research are: First, it is necessary to compare and analyze the four stages of translation and the stage of the creative problem-solving model presented by ANT. Second, it is expected that there will be follow-up studies that apply specific cases centering on ANT.

• Atmosphere
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• v.26 no.1
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• pp.185-192
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• 2016

In this paper, I studied about historical seasonal subdivision system and a theory of traditional monthly order, which was used for so long from Koryo dynasty to the late of Choseon dynasty in Korean histoy. Especially, I took note of the fact that there used the table of solar terms and meteorological observation what we called the table of Kihoo-pyo in the historical Sunmyung-calendar and the Soosi-calendar during the Koryo dynasty. This table of Kihoo was developed for explaining meteorological change during a year at that time. Here are largely four elements related meteorological nature : the first is the list of 24 solar terms, and the second is 12 monthly seasonal terms and 12 monthly central terms, the third is about four right hexagon based I-ching, the fourth is 72 meteorological observations called 72-hoo. Among them, the 72-hoo system is important to know how premodern people observed natural materials including animals and plants, weather, climate about meteorological phenomena according to the seasonal change or solar terms' change during a year. I argued in this article to need developing modern new table of Kihoo system like that, in order to show common people to recognize annual meteorological change more easy and clear. I also argued to need a distinct definition of meteorological seasons from a view point of modern meteorology.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.12
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• pp.93-104
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• 2019

This study set out to analyze the architectural trends in Bell's works and spaces by applying the Gaze theory of Jacques Lacan to his minimalism works, concept changes in their changing process, and the development of exhibition spaces related to him. The findings were as follows: first, his early glass cube works sought after the reproduction of the Real Order through the repeating eyes of viewers and objects by using exhibition lighting; second, his works in the Standing Wall category pursued the reproduction of the Real Order through the repeating eyes of many different viewers around objects; third, his Nesting Boxes tried to reproduce the Real Order of a higher competition level in the perception aspects, making the repetitive elements of Standing Walls converge and including even external environmental elements; fourth, there is no decisive gaze sought after by Judd or the Key Signifiant as the core of Lacan's philosophy in Bell's formative works; and finally, Bell's works pursue the completion of Simulacrum through the infinite repetition of Derrida's Deconstruction Philosophy through the infinite visual repetition sought after by Gehry and Moss in the LA School of Architects who shared the same area and period with him.

• Journal of the Korean earth science society
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• v.38 no.2
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• pp.105-114
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• 2017

Two dimensional finite element method with quadrilateral basis functions was applied to the spherical high order filter on the spherical surface limited area domain. The basis function consists of four shape functions which are defined on separate four grid boxes sharing the same gridpoint. With the basis functions, the first order derivative was expressed as an algebraic equation associated with nine point stencil. As the theory depicts, the convergence rate of the error for the spherical Laplacian operator was found to be fourth order, while it was the second order for the spherical Laplacian operator. The accuracy of the new high order filter was shown to be almost the same as those of Fourier finite element high order filter. The two-dimension finite element high order filter was incorporated in the weather research and forecasting (WRF) model as a hyper viscosity. The effect of the high order filter was compared with the built-in viscosity scheme of the WRF model. It was revealed that the high order filter performed better than the built in viscosity scheme did in providing a sharper cutoff of small scale disturbances without affecting the large scale field. Simulation of the tropical cyclone track and intensity with the high order filter showed a forecast performance comparable to the built in viscosity scheme. However, the predicted amount and spatial distribution of the rainfall for the simulation with the high order filter was closer to the observed values than the case of built in viscosity scheme.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.331-346
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• 2021

The purpose of this study was to comprehensively examine the effect of capstone design education on learning outcomes and propose directions for effective design and implementation of capstone design classes. For achieving this, a 21 studies meeting the standards among the academic journals and thesis published in Korea by September 2020 were selected, and based on 83 effect sizes, the meta analyses were carried out. The results of this study were as follows: First, the total effect size of capstone design education was 0.96, which is a large effect size. Second, the effect size was large in order of affective, cognitive, and social areas. Third, the effect size of vocational basic ability showed a large effect size while creativity showed a medium-sized one. Fourth, the effect size showed highest for design subject, the grade in the third or fourth, there was help from industrial corporation, theory and practice. Based on these results, this study proposed instructional design implications in order to increase the learning effects of capstone design in Korea.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.204-211
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• 2020

The era of the 4th industrial revolution is a complex environment in which the cyber world and the physical world are integrated and interacted. In order to successfully implement and be sustainable the 4th industrial revolution of hyper-connectivity, hyper-convergence, and hyper-intelligence, not only the technological aspects that implemented digitalization but also the social aspects must be recognized and dealt with as important. There are socio-technical systems and socio-technical systems theory as concepts that describe systems involving complex interactions between the environmental aspects of human, mechanical and tissue systems. This study confirmed how the Socio-technical System was applied in the research literature for the last 10 years through machine learning-based analysis. Eight clusters were derived by performing co-occurrence keywords network analysis, and 13 research topics were derived and analyzed by performing a structural topic model. This study provides consensus and insight on the social and technological perspectives necessary for the sustainability of the 4th industrial revolution.

• Knowledge Management Research
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• v.7 no.1
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• pp.81-96
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• 2006

The purpose of this study is to survey what strategy BACHE, a bathtub manufacturing company, chooses to implement knowledge management. Generally speaking, the success factors of this case company is follow-up management. The first factor is to use linguistic metaphors for employees to understand difficult knowledge management terms easily. The second one is that CEO tries to set and lead pro-knowledge management corporate culture. The third one is based on the CKO's competence to read business circumstances and apply the theory of knowledge management to the workplace. The fourth one has something to do with a way of knowledge creation, for example, a suggestion system and QC circle. The fifth one depends upon CKO's mission to share knowledge invented from his own company's with the rivals and large companies which order bathtubs so that overall bathtub industry can upgrade knowledge management.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1091-1096
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• 2003

The effects of different polarization conditions on vibrational echo signals are systematically explored for the rigid cyclic dipeptide 2,5-diazabicyclo[2,2,2]octane-3,6-dione. An anharmonic vibrational Hamiltonian is constructed by computing energy derivatives to fourth order using density functional theory. Molecular frame transition dipole orientations are then used to calculate polarization dependent orientational factors corresponding to various Liouville space pathways. Enhancement and elimination of specific peaks in twodimensional correlation plots is accomplished by identifying appropriate pulse configurations.

• Structural Engineering and Mechanics
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• v.24 no.1
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• pp.51-62
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• 2006

Differential transform method (DTM) for free vibration analysis of both ends simply supported beam resting on elastic foundation is suggested. The fourth order partial differential equation for free vibration of the beam resting on elastic foundation subjected to bending moment, shear and axial compressive load is obtained by using Winkler hypothesis and small displacement theory. It is assumed that the material is linear-elastic, and that axial load and modulus of subgrade reaction to be constant. In the analysis, shear and axial load effects are considered. The frequency factors of the beam are calculated by using DTM due to the values of relative stiffness; the results are presented in graphs and tables.