• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.897-907
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• 2020

The flow characteristics of reactor fuel assembly always intrigue the designers and the experimentalists among the myriad phenomena that occur simultaneously in a nuclear core. In this work, the visual experimental method has been developed on the basis of refraction index matching (RIM) and particle image velocimetry (PIV) techniques to investigate the detailed flow characteristics in China fast reactor fuel subassembly. A 7-rod bundle of simulated fuel subassembly was fabricated for fine examination of flow characteristics in different subchannels. The experiments were performed at condition of Re=6500 (axial bulk velocity 1.6 m/s) and the fluid medium was maintained at 30℃ and 1.0 bar during operation. As for results, axial and lateral flow features were observed. It is shown that the spiral wire has an inhibitory effect on axial flow and significant intensity of lateral flow mixing effect is induced by the wire. The root mean square (RMS) of lateral velocity fluctuation was acquired after data processing, which indicates the strong turbulence characteristics in different flow subchannels.

• The Korean Journal of Health Service Management
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• v.8 no.3
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• pp.207-218
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• 2014

This study was to compare the recognition of future career and nurse's characteristics according to nursing school system. This study was based on cross sectional descriptive method. The data were analyzed by $x^2$-test, t-test, and ANOVA using PASW WIN 18.0 program. The data represented that students who were doing associated degrees or bachelor degrees, showed the similar level recognition of future career and nurse's characteristics. However they showed differences in recognition of the career where they could create and new things(t=2.933, p=.004) and working part time(t=2.328, p=.021). In regards to recognition of nurse's characteristics bachelor degrees students had higher professional ethics($4.59{\pm}.44$). This study proposed that these research results could be used for improving methodology of nursing education.

• Journal of IKEEE
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• v.20 no.4
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• pp.416-419
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• 2016

When the integration density and operating frequency increase in the electronic circuits, it is important to improve the signal transmission characteristics. In this paper, the signal transmission characteristics of the printed circuit boards are analyzed with the curvature of the pads. From the simulation results, signal transmission characteristics are improved when pad curvature increases. Pad curvature more effects on signal transmission characteristics when the thickness of the transmission line and the length of the transmission decrease.

• The Journal of Sustainable Design and Educational Environment Research
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• v.18 no.2
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• pp.12-21
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• 2019

In the wake of the fourth industrial revolution, the paradigm of human resources and education required by reality is changing. School buildings are also improving to accommodate changed education and with that move, school building reform policies have been established at home and abroad. The purpose of this study is to present the architectural planning characteristics of Future Schools related to space design. The research methods are as follows: First, the characteristics of Future School planning are compiled through prior research surveys in Korea. Second, the characteristics outlined earlier through advanced case analysis are examined of their application to architectural planning in order to establish the status of utilization factors, and the direction of planning is presented. This study names the school architecture as 'Future School' in reference to the use of the term in the preceding study. This study is meaningful in that it focuses on architectural planning characteristics in Future School planning and on actual application cases of theory.

• Research in Mathematical Education
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• v.17 no.2
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• pp.79-97
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• 2013

This paper reports findings from a survey of senior secondary school students' epistemological conceptions of mathematics with the adaption of the instrument of the "Conceptions of Mathematics" - Inventory in China. The survey included a sample of 414 Grade 10 students, 441 Grade 11 students, and 400 Grade 12 students from three provinces. Descriptive statistics, one-way ANOVA, and T-test were employed to analyze data in this study. It was found that senior secondary school students mainly focused on objectivity and reality of mathematics, without highlighting the characteristics of sociality, subjectivity, and creativity of mathematics. In addition, besides gender differences, differences were identified among students from different grades, different areas, taught by teachers with different teaching experience and experience in using reformed curriculum.

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.2
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• pp.98-103
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• 2009

An RF test structure is proposed and its applicability is confirmed by measuring DC characteristics and high frequency characteristics. Effective mobility extraction is also performed to confirm the validity of proposed test structure. The area of suggested test structure consumed on wafer was decreased by more than 50% and its characteristics do not be degraded compared with conventional structure.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.78-83
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• 1999

Fretting Wear Behavior and Characteristics were investigated with Inconel 690 tube which is used in Nuclear Power Plant. Fretting Wear Tester has been engaged in the study of characteristics on tube fretted induced to various factors, i.e. vibration amplitude, contact type, material properties load support geometry, environmental effect Test has been performed in air and at room temperature. Wear volume rate has been approximately estimated as a function of normal load.

• Journal of Aerospace System Engineering
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• v.14 no.6
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• pp.68-73
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• 2020

Skin-stringer structures are widely used in aircrafts due to their advantage of minimizing structural weight while maintaining load carrying capacity. However, buckling load can cause serious damage to these structures. Therefore, the buckling characteristics of skin-stringer structures should be carefully considered during the design phase to ensure structural soundness. In this study, finite element method was applied to predict the buckling characteristics of stiffened panels. In terms of the failure mode, finite element analysis showed a symmetrical buckling mode, whereas an asymmetrical mode was determined by experimentation. The numerical results were obtained and compared to the experimental data, showing a difference of 9.3% with regard to the buckling loads.

• Journal of the Korean housing association
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• v.14 no.5
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• pp.95-104
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• 2003

The purpose of this research is to find out environmental characteristics of elementary school children's room, and determine the relationship between children's room environment and their emotional characteristics. For the research, used were a developed measurement instrument for environmental characteristics of children's room as well as the emotion measurement instrument published by Korean Testing Co. and developed by Dr. Lee Jong-seung for elementary school children in their higher year grades. The results showed that environmental characteristics of children's room has relationship with children's emotional characteristics. The order of environmental characteristics had a direct and high relationship with children's emotional characteristics, while originality had indirect relationship with children's emotional characteristics through intervening variables. The human relationship of children's emotional characteristics was the most influenced by children's room environmental characteristics.

• Journal of The Korean Association For Science Education
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• v.15 no.3
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• pp.291-302
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• 1995

Most middle school and high school students learns under the same study plans and educational courses. Such an equal level education policies prevent the science-gifted from developing and promoting their ability. So it is severely necessary to sort out the gifted in science and make them develop their ability. In this paper, the attitudes of teachers and parents toward the science-gifted student in middle school were investigated as well as the characteristics of the gifted. One hundred science teachers of middle school who recommended the gifted in science and their parents in Seoul area were questionnaired. The follows are the consequences of investigation. 1. Most teachers and parents of the gifted considered that the school should do a special care for the gifted in science. That is, they prefer the enrichment course to the acceleration course for it. 2. The teachers play the role of motivating the study and promotion very well, but do not well as either the advisor or the cooperator with the parents because of their excessive work and lack of professional knowledgement about education of the gifted. 3. The parents play the role of the advisor or the counselor well, but do not well as the cooperator with school. 4. Among the characteristics of the gifted, there are not any differences between boys and girls in conduct characteristics. But there are meaningful difference in emotion characteristics. 5. The education of the gifted is very important for developing of country and personal promotion. So the administrative and financial support are necessary in order to sort out the gifted in science earlier and provide various programs.