• Journal of Korean Elementary Science Education
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• v.28 no.2
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• pp.213-228
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• 2009

The purpose of this study was to examine whether the new introduction of elementary science experiment specialist is appropriate under the current situation of serious emphasis of the importance in science experiments in elementary science in Korea. For this study, the survey items were developed twice through the preliminary study. The results show that most elementary teachers consider the importance of experiment in elementary science and the critical role of science experiments to increase students' curiosity and scientific understanding. About 80% of the teachers stressed the professionalism in elementary science. Although 65% of the teachers believed their having basic professionalism, 53% of them appealed the difficulty in teaching science experiments to students. Nevertheless, 67.5% of the teachers opposed to the idea of teaching elementary science in separation between experiment and theory in science, and only 8% of them agreed the idea of induction or adoption of the college graduates majoring in science and engineering, or holding the secondary teacher's certificate. Further, over 60% of the teachers responded no necessity of inducing the new policy of elementary science specialist. Many numbers of teachers revealed their serious worries about the new policy because of their past experience to suffer from the side effects of inducing the teachers with secondary teacher certificate to the elementary school. In particular, they also made a proposal to make a good use of the current system of exclusive elementary science teacher in Korea. The educational implication and suggestions for policy making were discussed.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.6
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• pp.685-691
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• 2000

In order to provide basis for an accurate concentration determination of volatile organic compounds(VOCs) in air, four different institutions participated in simultaneous measurements of several VOC species under the experimental scheme of the Measurement and Analysis Division(MAD) of the Korea Society for Atmospheric Environment(KOSAE). Two types of experiments were undertaken by collecting and analyzing ambient air samples from the 7th floor of Natural Science Building, Han Tang University during two day periods of the late May 1998. The first typer of experiment was conducted as five consecutive experiments at 2-hour intervals by two institutions. On the other hand. the second type of experiment was performed as two -10hr sampling by three different institutions. The data obtained from different type of experiments were examined using various statistical approaches. In general, the results of these experiments indicated that the VOC data produced by a number of Korean institutions be fairly agreeable.

• Applied Microscopy
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• v.31 no.4
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• pp.315-323
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• 2001

In situ TEM heating experiments utilizing kaolinite powder samples result in the following facts. (1) The water recirculation system adopted in the Gatan's heating holder is required to prevent specimen drift above $500^{\circ}C$. (2) Since the degree of phase changes depends on the thickness of powders below $600^{\circ}C$, examinations of both thin and thick specimens are required. (3) Sample preparation using Mo-grids is required for TEM heating experiments above $900^{\circ}C$. At these temperature ranges the effect of heating rate and holding time on the phase transition process increases drastically, so that a programmed temperature control is required. (4) TEM heating experiments of the embedded powders by epoxy for the cross-sectional view was limited due to the severe epoxy movement during heating above $300^{\circ}C$. Better methods of sample preparation are required to overcome this problem.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.5
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• pp.422-431
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• 2015

Wind tunnel testing to construct static aerodynamic database of KF-16 was conducted for preceding research of design of experiments in wind tunnel testing. The test model is KF-16 scaled 1/33 and it has horizontal tail, flaperon, and rudder. The experiments consist of one experiment for analyzing aerodynamic coefficients under whether or not horizontal tail is present and four experiments for analyzing aerodynamic coefficients of changes of deflection angle in control surface which are flap, flaperon, rudder, and horizontal tail. After conducting wind tunnel testing, the experimental results show that the control surface changes have a great effect on Aerodynamic characteristics.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.402-407
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• 2022

Statistical design of experiments was used to optimize the MOF-5 synthesis process. A mixture design was employed to optimize precursor concentration. The optimal composition of three chemical materials, terephthalic acid, zinc acetate dihydrate, and N,N-dimethylformamide for MOF-5 synthesis was determined by extreme vertices design methods as follows; 1 mol : 2.7 mol : 40 mol. A multilevel factorial design was selected to screen the significance of synthesis reaction conditions such as temperature, time, and stirring speed. Statistical analysis results suggested excluding stirring speed from further investigation. Using a central composition design, the synthesis time and temperature were optimized. The quadratic model equation was derived from 13 synthesis experiments. The model predicted that MOF-5 synthesized at 119 ℃ for 10.4 h had the highest crystallinity.

• Journal of the Korean Society of Earth Science Education
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• v.11 no.2
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• pp.107-115
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• 2018

To learn the Earth's shape is a very important achievement standard in the earth science education. The purpose of this study is for helping school experiments by investigating effective experiments of the Earth's shape of each stage of school. Researchers suggest various experiment methods to learn the Earth's shape and investigated appropriate experiments to stage of elementary school, secondary school, high school and university for 26 pre-service teachers. As a result, there is difference between schools in effective experiments of the Earth's shape. Pre-service teachers thought that to observe a sail of ship to come back to a harbour is effective for elementary school students. And they responded that to compare the altitude of the polar star by latitudes is good for the secondary and high school students and to compare difference of sight according to height of the ground is effective for university students. They thought that level of the experiment method, abstract thinking and depth of background knowledge should be considered when teachers choose an effective experiment of the Earth's shape.

• Journal of Science Education
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• v.45 no.2
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• pp.143-155
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• 2021

The goal of this study is to examine the Integrated Science and Science Laboratory Experiments of the 2015 revised curriculum applied since 2018, and to explore ways to improve these two subjects in preparation for the 2022 revised curriculum. A survey was conducted by randomly sampling high schools across the country, with a total of 192 science teachers participating. In addition, 12 high school science teachers were selected as focus group, and in-depth interviews were conducted to investigate ways to restructure common science courses for the next curriculum. Main research results include that most schools were operated in 6~8 units for Integrated Science, and the teachers in charge of Integrated Science per class averaged 2~3 over the three years. For Science Laboratory Experiments, it has operated for a total of two semesters, one unit per semester, and it was found that several science teachers are in charge of Science Laboratory Experiments to fill the insufficient number of hours regardless of major. In the in-depth interview, science teachers argued that Integrated Science should be reduced and restructured by strengthening key competencies in preparation for the high school credit system. Based on the research results, ways to reorganize Integrated Science focused on big ideas, ways to construct common science courses based on fundamental science concepts that can guide elective courses, the necessity of career guidance through common science courses, and the necessity of strengthening teacher professionalism for teaching interdisciplinary and multidisciplinary subjects were suggested.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.201-208
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• 2003

Since no information about the optimum plot sizes on field experiments on the major food crops in Korea is available, present status of plot sizes being used by the research institutes was examined for rice, barley & wheet, soybean, potatoes, red pepper, garlic and onion. The optimum plot sizes in field experiments on these crops were estimated on the basis of soil fertility indices (Smith's regression coefficients) that Chang (1983) reported.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1299-1307
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• 2006

This study investigates solving production problems in an automotive stamping plant using Finite Element (FE) analysis. The fundamentals of stamping, metal plasticity and FE analysis are developed. In this paper, we provide the basis for a simulation of the stamping of a production part, the automotive rear floorpan. On-plant factorial Design of Experiments (DoE) were simulated using the floorpan model. The accuracy of the simulations was undetermined because of variability in the DoE results. Predictions of flange shape, wrinkling and thickness show qualitative agreement with manufactured parts and indicate that simulating an industrial part is feasible.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.45-48
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• 1996

The most research on facility layout problems ignored the actual shape of building where the activities(departments) are to be arranged. They also ignored the aisles between departments inside the building. In this paper, we present a genetic algorithm that searches a very good facility layout with horizontal aisles for two different cases with respect to the department shape. From the extensive experiments, the proposed genetic algorithm generated better layouts than the ones obtained by applying Tam's algorithm. It showed about 10% improvement of performance. We found out the best combination of genetic operators through the experiments.