• Communications of Mathematical Education
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• v.21 no.2 s.30
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• pp.271-282
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• 2007

Producing tools for actively meeting social needs in a radical changing society due to the development of modern technology has been shifted from physical ability to intelligent ability. The prominence of educating creativity is perceived as a good preparation in order to deal with them. Considered that assessment which is systematic activity to collect, analyze, diagnose, and judge information of a series of instruction practices is means to impart evidence and feedback of teaching learning practices, education and assessment is placed on reciprocal relationship. Nevertheless, there has been some tendency of neglect of assessment, comparing education for upbringing creativity. In this paper model of pencil and paper problem is discussed focusing on the sub-components of creativity and problem solving as one of the variety of means to extend mathematical creativity.

• Journal of Korean Elementary Science Education
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• v.26 no.4
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• pp.407-417
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• 2007

The purpose of this research is to develop standards with which we can design an instrument to assess classifying inquiry skills by observing students' behavior and reported outcome which is not the paper and pencil test. This research is focused on developing a standard for analysis of classifying ability among research functions. To identify classifying inquiry skills, standards from classifying behaviors were comparing ways with other cards and using information included in the cards; Standards selected from the final reports were the appropriateness, inconsistency and hierarchy of the classification outcome. The standards were initially selected during the class with picture cards printed various birds appearances on the front side and their traits on the back which was specially designed among sixth graders. The picture cards prepared with plant leaves and stems had designed to identify whether standards was effective to assess student's classifying ability. The standards was an effective tool to assess student's classifying inquiry skills.

• Journal of Korean Elementary Science Education
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• v.20 no.1
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• pp.123-137
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• 2001

In this study, the contents of elementary school science textbooks related to 'heat and temperature' are analyzed and alternative conceptions ofi"heat and temperature" among students enrolled in grades 4, 5 and 6 are investigated. 259 students were selected from a elementary school located in urban area. The relationships between students' alternative conceptions and the content of elementary science textbooks are also examined. Students' conceptions are analyzed from their answers to a paper-and-pencil test. The typical alternative conception of "heat and temperature" held by students was follows. They think that "heat" is a material and "temperature" is value of heat amount. They can't distinguish between "heat" and "temperature". Their explanation of "heat and temperature" is focused on hot or cool sensation and other observable characteristics of a material. A textbook analysis indicated that contents on "heat and temperature" were organized without the viewpoint of particle motion theory. This may be one of the causes of students' alternative conceptions.

• Journal of the Korean institute of surface engineering
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• v.28 no.5
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• pp.289-299
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• 1995

The effects of phosphate coating have been studied on physical properties and corrosion resistance of painted aluminum alloy sheet for automobile body. The physical properties (surface roughness, paint adhesion, impact resistance and pencil hardness) and corrosion resistance(cyclic corrosion and filiform corrosion) were investigated. Phosphate coatings enhanced the physical properties of painted Al alloy sheet, especially paint adhesion after the 240hours water immersion test. Phosphate coating also markedly improved the resistance for cyclic corrosion and filiform corrosion of painted cold rolled steel and Zn-Ni plated steel sheet as well as painted Al alloy sheet. The corrosion resistance of painted Al sheets was varied with the concentration of free fluoride ion and metal additives like Ni and Mn in the phosphating bath. A maximum corrosion resistance was obtained at about 300ppm of fluoride ion and additives of Ni and Mn obviously increased the corrosion resistance of painted specimens.

• Journal of The Korean Association For Science Education
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• v.17 no.3
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• pp.239-249
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• 1997

Primary students' conceptions on the atmospheric pressure and its related concepts were investigated. Samples consisted of 41 5th grade and 43 6th grade primary school students. Two types of research methods were used: 1) the open-ended written questionnare;2) paper-pencil test. Naive theories on the atmospheric pressure and its related concepts were numerous. For example, 80% students thought that as we go higher into the atmosphere, the atmospheric pressure becomes greater. Also, 50% students thought that the hot air had greater the atmospheric pressure than the cold air. This study was also discussed the teaching strategies to overcome these naive theories on the atmospheric pressure and its related concepts.

• ETRI Journal
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• v.36 no.3
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• pp.460-468
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• 2014

This paper addresses the problem of joint time of arrival (TOA) and direction of arrival (DOA) estimation in impulse radio ultra-wideband systems with a two-antenna receiver and links the joint estimation of TOA and DOA to the sparse representation framework. Exploiting this link, an orthogonal matching pursuit algorithm is used for TOA estimation in the two antennas, and then the DOA parameters are estimated via the difference in the TOAs between the two antennas. The proposed algorithm can work well with a single measurement vector and can pair TOA and DOA parameters. Furthermore, it has better parameter-estimation performance than traditional propagator methods, such as, estimation of signal parameters via rotational invariance techniques algorithms matrix pencil algorithms, and other new joint-estimation schemes, with one single snapshot. The simulation results verify the usefulness of the proposed algorithm.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.121-125
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• 2003

Enzymatic polymerization of cardol derived from cashew nut shell liquid have been examined. t-Butyl alcohol aqueous systems showed high yield of polycardol when SBP was as biocatalyst. Compared other solvents, peroxidase actiyity was maintained stable, which was seemed major cause. Solvent aqueous system and concentration of hydrogen peroxide were found to have an influence on the yield and molecular weight distribution of polycardol under the reaction of enzymatic polymerization using peroxidase. The polymer was subjected to the hardening by methyl ethyl ketone peroxide and cobalt naphthenate catalyst, giving a crosslinked tough film. Polycardol was cured rapidly and the hardness increased with time. Finally, the pencil scratch hardness reached to 7H, which is enough hard for industrial uses.

• The Mathematical Education
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• v.44 no.4 s.111
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• pp.587-602
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• 2005

The primary purpose of this study was to investigate how number sense performance of sixth graders was and what every character of five components of number sense possessed by sixth graders was. For the this purpose, Two kinds of studies were conducted : a descriptive study by pencil-and-paper tests(Basic Test, Number Sense Test) and a clinical study by interviews. The conclusions drawn from the results obtained in the this study were as follows : First, students were highly scored in Basic Test but not highly scored equally in Number Sense Test. Second, students hardly used the benchmarks and lacked consideration of the reasonableness about computation results. Interview results were that students' notion about the meaning, and the greater - than and less - than relations for fractions was weak and students tended to not use number sense but apply standard algorithm and compute numbers in the question without thinking.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.85-85
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• 2013

A ceramic coating material with nano-sized silicon oxide on AISI 4340 steel for a thermal conductor at a high temperature was analyzed to find an optimum coating process. Average surface roughness of the coating layers prepared by dipping process was about $5.26{\mu}m$. Potassium silicate addition as a binder of the coating material tended to improve its hardness. A pencil scratch hardness testing showed that a loading more than 800 g made fragments of the coating layer.

• Toxicological Research
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• v.28 no.2
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• pp.123-127
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• 2012

Voltammetric detection of the toxic Zn ion was investigated using a fluorine-doped graphite pencil electrode (FPE). It is notable from the study that pencils were used as reference and working electrodes. In all the experiments, a clean seawater electrolyte solution was used to yield good results. The analytical working range was attained to 10 ${\mu}gL^{-1}$. The optimized voltammetric condition was examined to maximize the effect of the detection of trace Zn. The developed sensor was applied to an earthworm's tissue cell. It was found that the methods can be applicable to in vivo fluid or agriculture soil and plant science.