• Journal of the Korean Society of Earth Science Education
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• v.14 no.3
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• pp.257-266
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• 2021

This study investigated the understanding of pre-service teachers in relation to the 'fog experiment' in the 5th grade 'Weather and Our Daily Life' unit of the 2009 and 2015 revised elementary school science textbooks. Pre-service teachers who participated in this study were 100 students, who are attending the university of education and taking courses in teaching research. After pre-learning about the 2009 and 2015 revised elementary school science textbooks and guide book, pre-service teachers conducted the experiment in groups. After that, the pre-service teachers individually presented answers to three questions, and the results of analyzing the answers are as follows. First, there were 24 (24%) preservice teachers who explained the difference in fog generation in the 2009 and 2015 revised curriculum with related scientific concepts such as condensation and water vapor, and only 1 (1%) of them explained the difference using the concept of saturation. Second, there were 48 (48%) pre-service teachers who found out the reason for the change in the fog experiment method according to the change in the curriculum. Third, pre-service teachers valued the reproduction and success of experiments rather than the importance of scientific knowledge, and such pre-service teachers suggested the use of alternative experiments or website.

• Journal of ILASS-Korea
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• v.22 no.1
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• pp.13-21
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• 2017

The fog screen is a device projecting the media to the aerosol flow field. As major parameters to generate dense and steady fog screen, shear stress, optical blockage ratio and SMD were obtained result through experiment. The micro droplet was generated by the piezo oscillation element, and the aerosol flow mixed with an air flow was sprayed into the vertical direction from the top of the fog screen through the 280 mm slot. For produce a dense, uniform fog screen, the shear effect, optical blockage ratio and SMD between aerosol and air curtain were measured. The minimum and maximum shear stress conditions were selected and it was confirmed that the optical transmission deviation of the aerosol flow field was small when the aerosol and air curtain flow rates were changed. When the aerosol and air curtain flow power were 18 V (1.51 m/s) and 24 V (2.55 m/s), respectively, under the condition of the minimum shear stress and laminar flow, the optical blockage ratios with the spray length were small, and it produced a most stable and high density uniform fog screen by injecting a constant of $10{\mu}m$ or less.