• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.3
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• pp.424-431
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• 2003

The spacer grid is one of the main structural components in the fuel assembly, which supports the fuel rods and maintains coolable geometry from an external load. A vibration test and a finite element analysis using ABAQUS on a dummy fuel rod continuously supported by Optimized H type(OHT) and New Doublet (ND) spacer grids arc performed to obtain the vibration characteristics such as natural frequencies and mode shapes an(1 to verify a finite element model. The results from the test and the finite element analysis are compared by modal assurance criteria (MAC) values. It is resulted that MACs for the first, the third and the fifth mode shapes are relatively good as compared with those of the second an(1 fourth ones. The natural frequency differences between two methods as well as the mode comparison results for the rod with OHT spacer grid are better than those with ND spacer grid. It is judged that the FE model for the ND spacer grid spring should be modified to consider the long contact length which actually happen when the spring supports the rod.

• Steel and Composite Structures
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• v.10 no.3
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• pp.207-222
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• 2010

Fire incident in buildings is common, so the fire safety design of the framed structure is imperative, especially for the unprotected or partly protected bare steel frames. However, software for structural fire analysis is not widely available. As a result, the performance-based structural fire design is urged on the basis of using user-friendly and conventional nonlinear computer analysis programs so that engineers do not need to acquire new structural analysis software for structural fire analysis and design. The tool is desired to have the capacity of simulating the different fire scenarios and associated detrimental effects efficiently, which includes second-order P-D and P-d effects and material yielding. Also the nonlinear behaviour of large-scale structure becomes complicated when under fire, and thus its simulation relies on an efficient and effective numerical analysis to cope with intricate nonlinear effects due to fire. To this end, the present fire study utilizes a second-order elastic/plastic analysis software NIDA to predict structural behaviour of bare steel framed structures at elevated temperatures. This fire study considers thermal expansion and material degradation due to heating. Degradation of material strength with increasing temperature is included by a set of temperature-stress-strain curves according to BS5950 Part 8 mainly, which implicitly allows for creep deformation. This finite element stiffness formulation of beam-column elements is derived from the fifth-order PEP element which facilitates the computer modeling by one member per element. The Newton-Raphson method is used in the nonlinear solution procedure in order to trace the nonlinear equilibrium path at specified elevated temperatures. Several numerical and experimental verifications of framed structures are presented and compared against solutions in literature. The proposed method permits engineers to adopt the performance-based structural fire analysis and design using typical second-order nonlinear structural analysis software.

• Speech Sciences
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• v.9 no.2
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• pp.89-108
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• 2002

Deaccentuation' means the phenomenon that the accent on the particular element which deserves to be accented, disappears and loses the property of intonational prominence. Based on some theoretical background, we divided the cases where deaccentuation can be placed into six categories : the first, the case that the words already mentioned are repeated in the context; the second, the case that the element can be recovered anaphorically or situationally; the third, the case that the elements are semantically weightless; the fourth, the case that the meaning of the word is empty; the fifth, the case that the elements are less informative, so that they are easy to predict; the sixth, the case that the elements are located after the focused words. Then we organized the context and the experimental sentences corresponding to each category. The utterances of Korean and English native speakers were recorded and analysed based on the ToBI system and compared to each other, in order to find out that Korean speakers can distinguish the difference within each sentence pair, and produce them with appropriate intonation similar to that of native speakers.

• Journal of Welding and Joining
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• v.23 no.4
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• pp.73-80
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• 2005

Arc blow being occurred by Electro-Magnetic force(EMF) during the electric arc welding prevents the formation of a sound weldment. In this study, the effects of arc position, groove size, tack weld and base plate on the EMF in a butt-joint welding of mild steel plate are analyzed by a computer simulation based on the finite element method. The EMF can be numerically identified to be caused by a difference of the magnetic flux-density between ahead of and behind the arc in case that the workpiece locates asymmetrically around the uc. When there exists an air gap of groove ahead of the arc in the welding direction, the similar magnetic force has been producted regardless of the arc position and the gap size. The tack weld alleviates the magnetic force to about one fourth at the finish end of the workpiece. The magnetic force can be also significantly reduced with the base plate to about one fifth at the start end of the workpiece containing a tack weld.

• The Research Journal of the Costume Culture
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• v.30 no.2
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• pp.208-225
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• 2022

The purpose of this study is to identify trends in modern Korean clothing design through investigation and analysis of the types and respective characteristics of silhouettes, colors, materials, patterns, and decorations present. To this end, research methods such as literature research and content analysis through case study research were used. The results of the wedding magazine data analysis were largely classified by design element and based on such, the conclusions are as follows. First, in the analysis of silhouettes, the appearance rate of traditional items decreased over the selected period and that of modified items increased. Second, among the same colors, adjacent colors, proximity complementary colors, contrast, and other harmonies, adjacent color harmonies showed the highest rate of appearance. Third, the cases where the same materials were used for the top and bottom elements showed a similar appearance rate as those where different materials were used. It was also concluded that traditional materials are being replaced by modern materials. Fourth, regarding the arrangement of patterns, the appearance rate of the absence of patterns gradually increases. Fifth, there were more case of decorations than those of none. This study made it possible to grasp the changes in trends of modern Korean clothing from 2011 to 2020 and provide basic data for the development of the Korean clothing market industry.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1783-1796
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• 2015

The purpose of this study was to verify the formation of serious leisure experience for water sports mania using grounded theory method approach. Research participants were selected 6 water sports mania by reputational sampling method. Six participants who usually participated in water sports club were selected as research participants. The data for this study included participants' observation and in-depth interview. This study categorized the coding paradigm which was presented by using the findings derived from data as they were into casual condition, contextual element, central phenomenon, critical situation, mediative element, interaction, final result and core category to draw out the process of becoming a water sports mania and its significances. The results of were as follows. First, water sports mania recognized the environmentally safe pleasure and value. Second, water sports mania was in a race against myself. Third, water sports mania felt the social and environmental changes. Fourth, water sports mania was looking for alternative method. Fifth, water sports mania overcome physical limitations and liberation from fear of water. Lastly, water sports mania felt alive through the enthusiastic participation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.354-358
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• 1996

At design stage of the TRXI agricultural tractor transmission (New product of TongYang Moolsan Co., Ltd), the noise and vibration of the transmission were analyzed theoretically for the optimal design of the transmission . For this analysis, the finite element model was developed using a commercial computer software, ANSYS. The noise and vibration of the TRXI transmission housing were predicted by the modal analysis. Natural frequency of the TRXI transmission housing was ranged from 12.53Hz(1st mode ) to 30.05Hz(5th mode). The fifth mode took place at the bearing metal in the area of rear transmission housing and was very close to the gear mesh frequency (30.5Hz) of low rang gear at the low creep shifting . Based on the results , the bearing metal of the range shift housing was reenforced with the rib at design stage.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.2
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• pp.236-248
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• 2008

This study has explored the elements of e-teaching portfolio for enhancing teaching expertise in higher education. This study is carried out through the literature review and expert's focus group interview. As the result of this study, seven elements of e-teaching portfolio for enhancing teaching expertise in higher education have been found. First, 'personal background' include curriculum vitae, course responsibility, and other educational activities. Second, 'teaching philosophy' include the principals on teaching and learning, statements of teaching philosophy. Third, 'learning environment' include the characteristics of students, the previous learning contents, and physical environment. Forth, 'course contents and methods' include teaching strategies and instructional materials, Fifth, 'instructional evaluation' includes the principals of evaluation and the examples of learning outcomes. Sixth, 'endeavor for improvement of instruction' include evidence of activity for teaching improvement and instruction feedback from peer and students. And e-teaching portfolio also includes research career and awards history element.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.4
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• pp.270-276
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• 2018

Fifth-generation communications are approaching, and they will require broadband antennas that include the existing LTE frequency band (1.7 GHz to 2.7 GHz) and the newly allocated frequency band (3.4 GHz to 3.7 GHz). Many kinds of antennas satisfy the required broadband characteristics, including the dual-element folded dipole antenna proposed in this paper. A zigzag line was used to make the antenna more compact. This was accomplished by reducing the physical length while maintaining the electrical length. To validate the proposed antenna, a prototype was fabricated using PCB (${\epsilon}_r$:4.4, Height: 1.6 mm) and its performance was evaluated. Results obtained by simulation and experiment showed good agreement.

• Journal of Korean Elementary Science Education
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• v.39 no.3
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• pp.369-381
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• 2020

This study aims to analyse the relationship between multiple intelligence and scientific creativity of science-gifted elementary students focusing on the subject of biology. For this, 37 science-gifted fifth-graders in the Science-Gifted Education Center at an Office of Education conducted a multiple intelligence test. In addition, researchers collected science-gifted students' results of scientific creativity activity at the botanical garden field trip. The main findings from this study are as follows: First, strong intelligence was logical-mathematical intelligence for gifted students, and weak intelligence was found to be naturalistic intelligence for them. Second, there was no significant correlation in the relationship between multiple intelligence and scientific creativity of science-gifted students. Third, as a result of independent two sample t-test for each intelligence and scientific creativity scores divided into the upper and lower groups, only verbal-linguistic intelligence statistically differed significantly at the level of p<.05 (t=2.13, df=35, p=0.04). Fourth, as a result of conducting a two-way analysis to see if there were any interaction effects, verbal-linguistic and visual-spatial, logical-mathematical and visual-spatial, logical-mathematical and bodily-kinesthetic, and visual-spatial and musical-rhythmic intelligence all showed significant values at the level of p<.05 level in interaction effects on originality element comprising scientific creativity. Fifth, an analysis of students with high naturalistic intelligence showed that their scores of scientific creativity tasks conducted at the botanical garden field trip were all lower. Based on the results of this study, this study discussed the implications of scientific creativity learning linking multiple intelligence in primary science education and gifted education.