• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.236-239
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• 2002

The electron-atom collision studies has been essentially use\ulcorner for testing and developing suitable theories of the scattering and collision processes, and for providing a tool for obtaining detailed information on the structure of the target atoms and molecules and final collision products. And, the development of that has also been strongly motivated by the need for electron collision data in such fields as laser physic and development, astrophysics, plasma devices, upper atmospheric processes and radiation physics. Therefore, we explains the concept and the principle of determination of the electron collision cross sections for atoms and molecules by using the present electron swarm method.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.685-689
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• 2004

Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of HVAC(Heating, Ventilating and Air-Conditioning) for double' deck train. The HVAC system is installed under the roof of carbody. In the lay-out of HVAC system, air duct must be installed to supply air to 1st and 2nd floor respectively. The standard k-$\epsilon$ and LES models for turbulence and SIMPLE algorithm for pressure equation hased on finite volume method are used to solve the physic a] HVAC model. To assure convergence, QUICK scheme for momentum equation and the 2nd order upwind scheme for turbulent equations arc used. From the results of simulation, the temperature and velocity magnitude are also distributed uniformly in the interior of double-deck passenger car.

• Journal of Korean Elementary Science Education
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• v.39 no.2
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• pp.155-167
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• 2020

This study analyzed reference data for the physics section in science guidebooks for the third-sixth grade in elementary schools, according to the 2015 revised curriculum. It analyzed the reference data by categorizing them in terms of subjects, objectives and presentation forms and the visual data used in the reference data by categorizing their types. The findings show that the ratio of the science knowledge type was highest (53.8%) among the subjects of reference data in guidebooks for the science section, followed by the application to real life, and then, supplementary inquiry experiments and activities. The ratios of other types such as advanced science, environment, scientists and science history were, however, less than 1%, so they need to be improved. The ratio of knowledge provision was highest (40.5%) among the objectives of reference data but the ratios of conceptual supplementation and deepening were similar in ratio. Meanwhile, While the expository type (88.4%) accounted for most of the present forms of reference data, and photographs and illustrations (93.6%) also accounted for most of visual data suggested with reference data. Thus more various types of presentation forms and the extension of visual data seemed to be needed. This study is expected to provide some suggestions for the meaningful use of reference data in guidebooks for teachers and for the development of science guidebooks for teachers in elementary schools.