• Journal of the Korean institute of surface engineering
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• v.50 no.5
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• pp.392-397
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• 2017

The Young's modulus of a nanoscale titanium (Ti) thin-film was evaluated using a high-speed microcantilever resonating at the megahertz frequency in the present study. A 350 nm thick Ti film was deposited on the surface of a silicon microcantilever, and the morphology of the film was analyzed using the atomic force microscopy. The microcantilever was excited to resonate using an ultrasonic pulser that generates tone burst signals and the resonance frequency shift induced by the deposition of Ti was measured using a Michelson interferometer. The Young's modulus was determined through a modal analysis using the finite element method and the result was validated by the nanoindentation testing, showing good agreement within a relative error of 1.0%. The present study proposes a nanomechanical characterization technique with enhanced accuracy and sensitivity.

• Journal of Biomedical Engineering Research
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• v.31 no.3
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• pp.194-198
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• 2010

The effective Young’s modulus of a microfibril surrounded by water may be simply calculated by using the upper (Voigt) and lower (Reuss) bounds, which is one way to estimate the Young’s modulus in composite materials. The Steered Molecular Dynamics (SMD) has been used for estimating the Young’s modulus of a microfibril surrounded by water. In this paper, the result estimated by the upper (Voigt) and lower (Reuss) bounds shows 9.2% to 21.8% discrepancy from the result estimated by SMD, but introducing “efficiency of reinforcement parameter” removes the discrepancy and shows good agreement with the result estimated by SMD. We found the best fit for the Young’s modulus against the size of the gap between microfibrils. Also the steps using these bounds are much simpler than SMD.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.237-245
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• 2005

The purpose of this study is to investigate the effects of field-trip based environmental education on young children's environmental literacy. The subjects for the study Were the 40 children of five years old at two nursery centers in province. The questionnaire and checklist for parents and the children developed by the researcher were used in this study. The conclusion were as follows. First, the care center environmental education improved the young children's saving, and anti-pollution depending on their mother is reported. Second, the care center environmental education improved the young children's saving, recycling and anti-pollution depending on their teacher is reported. Results showed that the field-trip based environmental education improved environmental literacy.

• Journal of Digital Contents Society
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• v.18 no.5
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• pp.859-868
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• 2017

The purpose of this study is to investigate the research trend of robot education for young children and elementary students as a basic study for the development of hands-on robot program for young children. Trends by year, research contents, and effectiveness of 155 dissertations and journal papers from 2006 to May 2016 related to robot education for young children and elementary students were analyzed. The results were as follows. In the research subject, research was conducted in the order of integrated education, attitudes and awareness research, and response research for young children and programming education, design development research, and integrated education for elementary students. In the research method, observational research and development research were the most common in young children and elementary students, respectively. In the effectiveness validation, research on social and emotional interaction and research on creativity were the most common in young children and elementary students, respectively. Based on the results of this study, the analysis provided basic data for the development of programs for young children's hands-on robot activities and suggested the direction and implications of robot education in connection with SW education of young children and elementary students.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.2
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• pp.130-135
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• 2000

The characteristics of two different modes of perfusion culture, intermittent and continuous bleedings, were investigated by culturing the hybridoma cells producing von Willebrand Factor (vWF) monoclonal antibody (McAb) in a 15 L bioreactor without clogging the filter. Both culture methods exhibited similar profiles of cell density and metabolite concentrations during the culture period at the cell concentration of around 1${\times}$107 cells/mL. When the perfusion rate was increased, the intermittrnt bleeding culture showed problems of ammonia accumulation and decrease of cell viability. The continuous bleeding culture in terms of nutrient consumption and metabolite production kinetics. But the analysis of specific oxygen consumption rate showed that the specific oxygen consumption rate of intermittent bleeding culture was similar to that of exponential growth phase. The continuous bleeding culture showed higher specific oxygen consumption rate of intermittent bleeding culture. finally we proved the possibility of long-term operation of continuous bleeding culture and produced approximately 40 g of vWF McAb in a 15L bioreactor after one-month operation.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.75-81
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• 2023

The purpose of the study was to find out the effect of early childhood teachers' perception of young children's right and teachers' right on their implementation of respect for young children's right. For this, a questionnaire survey was conducted on 355 early childhood teachers working at early childhood education institutions in the Seoul metropolitan area. Collected data were analyzed with Pearson's correlation analysis and multiple regression analysis using SPSS 24.0. As a result, the higher the level of early childhood teachers' perception on young children's right and teachers' right, the higher the level of their implementation of respect for young children's right. In addition, early childhood teachers' perception of young children's right and teachers' right were found to be predictable variables on their implementation of respect for young children's right. Based on the results, we suggest a need to enhance early childhood teachers' perception not only on young children's right but also on teachers' right to enhance their implementation of respect for young children's right.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.2
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• pp.266-285
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• 2008

This study investigated the relationship between musical understanding and expression, the purpose of music education. It also intended to present the theoretical basis of integrated early childhood music education by examining into the necessity of it as a method to help young children with musical understanding and expression. The results of the study showed that either of the understanding and expression of music should be necessary and there is a mutual promotional relationship between them. It was found out that real musical understanding can be formed not by mechanical skill, but when the relationship between notes is understood with various experiences. Therefore an integrated early childhood music education became necessary as a principle of educational method to help young children with musical understanding and musical expression. Concretely it was found out to be necessary in terms of the characteristics, interest and concern of young children, the use and development of multi intelligence and the translation of the same knowledge into the same level.

• The Korean Journal of Ecology
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• v.25 no.6
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• pp.365-369
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• 2002

We had 18 eggs artificially hatched in a mass breeding place of black-tailed gulls and examined the individual recognition between young siblings in a laboratory environment. The results of the experiment showed that the young gulls selectively responded to their siblings and non-siblings at an early stage after hatching. It was shown that they began to recognize the begging call among the voice signals of siblings and non-siblings 15-16 days after hatching, and the chirirah call 11-12 days after hatching. Also, more significant results were shown with the chirirah call than with the begging call. In an experiment of visual recognition between siblings and non-siblings, the young black-tailed gulls approached their siblings significantly 9-10 days after hatching. The recognition between young siblings in a mass breeding place provides an important evolutionary indicator in terms of their social behaviors.

• The Journal of Korean Association of Computer Education
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• v.13 no.4
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• pp.41-50
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• 2010

So far, the researches about the Internet addiction testing are diverse and enormous. However, since the testing factors have the same importance, there is no discrimination among the factors. In our paper, we analyze the problems of the existing researches by using Lisrel and data mining algorithms. Next, we propose an alternative for the Internet addiction testing. In order to accomplish these, we make an questionnaire consisted of Young's test and then, we asked to 440 primary and secondary school students. In addition, we analyzed the problems of Young's test with factor analysis and then, we distinguish more important items from others with J48 and PART. Finally, based on this analysis, we propose a method to diagnose addicted students and prescribe them.

• The Korean Journal of Zoology
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• v.5 no.2
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• pp.9-12
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• 1962

The present observations on the perforation bored into young bivalve Tapes philippinarum (less than 2 mm in shell length) by boring snails were conducted at Sunjae Island in 1960 and Inchon Harbor inn 1962. 1. Young bivalves of the species which were left with bored in them were found both in Inchon Harbor and Sunjae Island. 2. The location of the holes in the valves of the young bivalve varied widely, while the holes of the adult bivalve were located at relatively definite position in the valves. 3. The author realized that the holes are bored by a species of snails that have radulas, for the inner diameters of the holes were much smaller than the router diameters. 4. The size of the holes in the valves of young bivalve was much smaller than those holes bored in adult valves. The minimum size of the holes was only 7.5microns in diameter. 5. The author considered that the boring snail is Natica severa that is found abundantly in Inchon Harbor and Sunjae Island and that this snail is the only species found in the particular areas and performs the above mentioned behavior. However, the author could not confirm experimentally the snail drilling young bivalve of Tapes philippinarum .