• Journal of the Korean Chemical Society
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• v.45 no.2
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• pp.162-176
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• 2001

This study was covered with the analysis of five kinds of the middle school science text books(chemistry part) based on the oth curriculum. Particularly, inquiry activities part was analyzed by the three dimension framework which consists of inquiry content dimension, inquiry process dimension and inquiry context dimension and the results are as follows;1. In the analysis of the contents in the middle school science textbooks(chemistry part), the average number of total pages was 197.6. The illustration and picture were contained 0.66 in number per a page, and the average number of further readings was 5.8.2. In the analysis of the inquiry content dimension of inquiry activities, the total number of themes in five kinds of textbooks was 222. And the number of imquiry activities in five kinds of textbooks was siverse : A textbook had 51, B texbook 49, C textbook 37 and E textbook 35.3. For the analysis of inquiry process dimension. it follows in the order of 'interpreing data and formulating generalizations (42.4%)','observation and measuring (38.1%)','seeing a problem and seeking ways to solve it (7.8%)' and 'building, testing and revising the theoretical model(11.7%)'.4. As for the analysis of the inquiry context dimension, the scientific context occupied 94.2%, the individual context 0.4%, the social context 2.7% and the technical context 2.7%. It shows that the proportion of STS(Science-Technology-Society) related contents in inquiry activities was only 5.8%.

• Journal of the Korean Geotechnical Society
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• v.40 no.1
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• pp.47-54
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• 2024

In current slope stability analysis techniques, slope stability is evaluated based on the saturated-soil theory. However, soil-water characteristics change frequently depending on the climate. Therefore, because the saturated soil theory has limitations, the application of the unsaturated soil theory is necessary for slope stability. It is also important to evaluate the engineering properties of unsaturated soil because the capillary absorption capacity is reduced due to heavy rain, thereby causing a reduction in slope stability. In this study, soil-water characteristic tests were performed using four samples with different fine contents (0%, 10%, 20%, and 30%) using granite-weathered soil in domestic production areas. In particular, to consider the previously conducted drying process as well as the evaluation of stability due to heavy rain on the actual slope, a wetting process was conducted, in which the water content was increased. In addition, the van Genuchten (1980) model, which is the most consistent theoretical equation for the experiment, was used with various theoretical equations, and the parameters were analyzed according to the fine content of the granite-weathered soil for the drying and wetting processes.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.11-21
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• 1999

For microelectronic packaging application, the crystallizable glass powder in CaO-$A1_2O_3-SiO_2-B_2O_3$system was mixed with various amounts of alumina inclusions (\approx 4 $\mu \textrm{m}$), and its sintering behavior, crystallization behavior, and dielectric constant were examined in terms of vol% of alumina and the reaction between the alumina and the glass. Sintering of the CASB glass powder alone at $900^{\circ}C$ resulted in full densification (99.5%). Sintering of alumina-filled composite at $900^{\circ}C$ also resulted in a substantial denslfication higher than 97% of theoretical density, In this case, the maximum volume percent of alumina should be less than 40%. XRD analysis revealed that there was a partial dissolution of alumina into the glass. This alumina dissolution, however, did not show the particle growth and shape accommodation. Therefore, the sintering of both the pure glans and the alumina-filled composite was mainly achieved by the viscous flow and the redistribution of the glass. Alumina dissolution accelerated the crystallization initiation time at $1000^{\circ}C$ and hindered the densification of the glass. Dielectric constants of both the alumina-filled glass and the glass-ceramic composites were increased with increasing alumina content and followed rule of mixture. In case of the glass-ceramic matrix composites showed relatively lower dielectric constant than the glass matrix composite. Furthermore, as alumina content increased, crystallization behavior of the glass was changed due to the reaction between the glass and the alumina. As alumina reacted with the glass matrix, the major crystallized phase was shifted from wollastonite to gehlenite. In this system, alumina dissolution strongly depended on the particle size: When the particle size of alumina was increased to 15 $\mu\textrm{m}$, no sign of dissolution was observed and the major crystallized phase was wollastonite.

• Archives of design research
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• v.18 no.2 s.60
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• pp.211-218
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• 2005

As digital Information equipment is new arrival, new paradigm such as 'function exist but form don't' is needed in the field of design. Therefore, the activity of design is focused on the relationship of human and machine against visual form. For that reason, it is involved emotional factor in the relationship and studied on new field, the emotional interlace. The goal of this paper is to suggest the way of emotional interface on searching multimedia data. The main target of paper is effect sound and human's step and the main way of research is visualization after measuring and analyzing numerically similarity level among emotion-words. This paper suggests the theoretical bad(ground such as personal opinion, the character of auditory information and human's step and case studies on the emotion research. The experimental content about sound is fueled from my previous research and the main experimental content about human's step is made with regression-expression to substitute Quantification method 1 for value about stimulation. The realistic prototype to apply the research result will is suggested on the next research after studying the search environment.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.231-237
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• 1996

Defect equilibrium equations were modelled, and the relations of P $o_2$, venus x were derived using the mass action law. The dominant defect species active in a specified region were determined by fitting the curve of experimental data to the calculated curve of log P $o_2$, versus log x for each theoretical model. The calculated curve for (2:1:2) and (Er')$^{x}$ in the hyperstoichiometric $U_{1-y}$E $r_{y}$ $O_{2＋x}$ and that for (2Er'quot;)$^{x}$ $_{dec}$ in the hypostoichiometric $U_{1-y}$E $r_{y}$ $O_{2－x}$ are in good agreement with the present experimental results. The sintering behavior of Er-doped U $O_2$ is observed with erbium content in oxidizing and reducing atmospheres. For sintering in oxidizing atmosphere, sintered density decreases as increasing y in $U_{1-y}$E $r_{y}$ $O_{2＋x}$. However, in hydrogen atmosphere, sintered density decreases as increasing y at lower erbium content but the density increases again above y=0.10. In oxidizing sintering conditions, the formation of (Er'U')$^{x}$ clusters hinders the diffusion of cations, and hence the sinterability of Er-doped U $O_2$ decreases. In reducing atmosphere of Er-doped U $O_2$ for higher Er concent, the oxygen vacancies make (Er')$^{x}$ cluster decompose by charge compensation and the concentration of mobile cations increases, thereby improving the sinterability.ntration of mobile cations increases, thereby improving the sinterability.ability.

• Journal of Biosystems Engineering
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• v.36 no.3
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• pp.195-203
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• 2011

Not only does the labor of manufacturers used most in the drying process after rice harvest, but it also is having huge influence in quality. Also, because drying storage of rice production around the whole country is scarce with original facility, it has become a very important matter that farms develop their own safe and high-quality facilities to store and dry rice. Therefore, this study developed a small scale accumulated storage and drying bin, assessed nalyzed drying properties, and conducted analysis of research on the property of quality when storing for a long time. As a result, the drying speed of the small scale accumulated storage and drying bin was adequate of 0.042%/hr and was shown that the experimental static pressure and theoretical static pressure corresponded. Also, it was shown that drying cost was up to about 6 times inexpensive that heated air drying. For the storage of the small scale accumulated storage and drying bin, average of moisture content was around 16.5 until early April and decreased to 15.7% in July. Inside storage was maintained to 12.13% until early April and slightly increased to 14% after May. It was shown that inside storage had higher hardness and rate of cracking than the small scale accumulated storage and drying bin by storage conditions and germination rate was shown a little higher when stored in the small scale accumulated storage and drying bin.

• Korean Journal of Pharmacognosy
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• v.52 no.4
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• pp.257-266
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• 2021

This study evaluated several in vitro activities including the preliminary assessment of the anti-cancer, anti-inflammatory, and anti-diabetic effects of tree sprout extracts. Chlorogenic, caffeic, and p-coumaric acid contents in tree sprouts were analyzed using high-performance liquid chromatography and an ultraviolet detector. Among the studied tree sprout extracts, the ethanol (EtOH) extract of Rhus verniciflua exhibited the most potent anti-cancer effect by suppressing the cell viability of a human gastric adenocarcinoma cell line, with an IC₅₀ of 7.06 ㎍/mL. The EtOH extract of Morus alba (MAB) inhibited the secretion of nitric oxide (NO) at a concentration of 100 ㎍/mL, with an IC₅₀ of 83.44 ㎍/mL. Moreover, the EtOH extract of Securinega suffruticosa inhibited NO secretion with the lowest IC₅₀ of 54.42 ㎍/mL. The EtOH extract of Fraxinus mandschurica was the only extract with effective α-glucosidase inhibitory activity. The total content of chlorogenic, caffeic, and p-coumaric acids was the highest in MAB (14.63 mg/g ext.). In conclusion, the beneficial activities of the tree sprout extracts with high phenolic acid content were generally high. Our results provide a theoretical basis for the development of health-promoting supplements and functional foods.

• International Journal of Computer Science & Network Security
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• v.22 no.4
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• pp.401-407
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• 2022

Electronic media are an integral part of modern civilization; educational practices are no exception, which should change the content orientations, structures and methodological approaches in accordance with the requirements of the educational market. This makes it relevant to find effective and successful configurations in the process of implementing modern educational practices. The purpose of the research lies in determining the basic principles of electronic media and their place in modern education, identifying the effectiveness of teaching disciplines with application of electronic media, as well as establishing the level of assessment by students of the need to involve different types of electronic media in the educational process and professional practice. The research methodology is complex; the descriptive method and methods of observation, analysis and synthesis have been used in the academic paper. The method of pedagogical experiment has become the principal one; the method of questionnaires and statistical methods have been also used. The hypothesis of the academic paper lies in the fact that the involvement of electronic media in the educational process makes it more effective and requires conceptual changes in educational practices. The result of the research manifests in the identification of new opportunities for the use of electronic media, leading to conceptual shifts in the framework of modern educational policies. In the future, it will be appropriate to consider the theoretical aspects of changing worldview models in education and the use of new media in the educational process, their effectiveness and relevance.

• Safety and Health at Work
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• v.5 no.3
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• pp.118-124
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• 2014

Background: Satisfactory completion of mine safety training is a prerequisite for being hired and for continued employment in the coal industry. Although training includes content to develop skills in a variety of mineworker competencies, research and recommendations continue to specify that specific limitations in the self-escape portion of training still exist and that mineworkers need to be better prepared to respond to emergencies that could occur in their mine. Ecological models are often used to inform the development of health promotion programs but have not been widely applied to occupational health and safety training programs. Methods: Nine mine safety trainers participated in in-depth semi-structured interviews. A theoretical analysis of the interviews was completed via an ecological lens. Each level of the social ecological model was used to examine factors that could be addressed both during and after mine safety training. Results: The analysis suggests that problems surrounding communication and collaboration, leadership development, and responsibility and accountability at different levels within the mining industry contribute to deficiencies in mineworkers' mastery and maintenance of skills. Conclusion: This study offers a new technique to identify limitations in safety training systems and processes. The analysis suggests that training should be developed and disseminated with consideration of various levels-individual, interpersonal, organizational, and community-to promote skills. If factors identified within and between levels are addressed, it may be easier to sustain mineworker competencies that are established during safety training.

• Journal of Power Electronics
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• v.15 no.3
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• pp.819-829
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• 2015

This paper presents a shunt active power filter (SAPF) for compensating inter-harmonics and harmonics when inter-harmonics content is evident in the grid. The principle of inter-harmonics generation in the grid was analyzed, and the inter-harmonics effect on repetitive controllers was discussed in terms of control performance. Traditional repetitive controllers are not applicable in inter-harmonic compensation. Moreover, the effect of an ideal controller on harmonics signals was analyzed on the basis of the internal model principle. The repetitive controller was improved in the form of a basis function according to theoretical analysis. The finite-dimensional repetitive controller, which is also called the multiple-period repetitive controller, was designed for the control of multiple periodic signals. A selective harmonic compensation system was developed with SAPF. This system can be used to compensate harmonics and inter-harmonics in the grid. Finally, system control performance was verified by simulation and experimental results.