• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1653-1668
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• 2005

Assembly of hybrid mesophases through the combination of amphiphilic block copolymers, acting as structuredirecting agents, and silicon sources using low acid catalyst concentration regimes is a versatile strategy to produce large quantities of high-quality ordered large-pore mesoporous silicas in a very reproducible manner. Controlling structural and textural properties is proven to be straightforward at low HCl concentrations with the adjustment of synthesis gel composition and the option of adding co-structure-directing molecules. In this account, we illustrate how various types of large-pore mesoporous silica can easily be prepared in high phase purity with tailored pore dimensions and tailored level of framework interconnectivity. Silica mesophases with two-dimensional hexagonal (p6mm) and three-dimensional cubi (Fm$\overline{3}$m, Im$\overline{3}$m and Ia$\overline{3}$d) symmetries are generated in aqueous solution by employing HCl concentrations in the range of 0.1−0.5 M and polyalkylene oxide-based triblock copolymers such as Pluronic P123 $(EO_{20}-PO_{70}-EO_{20})$ and Pluronic F127 $(EO_{106}-PO_{70}-EO_{106})$. Characterizations by powder X-ray diffraction, nitrogen physisorption, and transmission electron microscopy show that the mesoporous materials all possess high specific surface areas, high pore volumes and readily tunable pore diameters in narrow distribution of sizes ranging from 4 to 12 nm. Furthermore, we discuss our recent advances achieved in order to extend widely the phase domains in which single mesostructures are formed. Emphasis is put on the first synthetic product phase diagrams obtained in $SiO_2$-triblock copolymer-BuOH-$H_2O$ systems, with tuning amounts of butanol and silica source correspondingly. It is expected that the extended phase domains will allow designed synthesis of mesoporous silicas with targeted characteristics, offering vast prospects for future applications.

• The Research Journal of the Costume Culture
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• v.26 no.1
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• pp.73-81
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• 2018

Developments in the recent media era has made distortion possible in accordance with changes in the fashion industry as new clothing, technologies, and fusions have become available. Nevertheless, previous studies of specific types of clothing, and their classification for the purpose of research are lacking. Thus, this study examines the development of the Pomme de look and the form of modern variant that appears in fashion clothing and new technologies, and largely examines the clothing case to clean it up. The method employed is leading research that examines the transformation about the concept of the Pomme de look with regard to the fashion about the type of look in the 2000s and onwards. This is organized in accordance with the analytical and physical characteristics, and the esthetic aspects of the results are as follows. The conclusions reached as follows are based on this; first, the physical characteristic manner when based on previous looks, the two-dimensional deformation for making clothes, if there was a simple way, now has more dimensions. Clothes are made in a complex manner and variations emerge. Second, esthetic characteristics strive for beauty while also displaying the modified and more complex manners of clothing that are emerging. Third, the fusion clothing with machines effects to physical and psychological changes through the details about how the sensor is worn. The enemy, the appearance of distortion, and clothing are emerging. This is expected to grow further based on the rapid development of new technologies and the transformation of Pomme de look and design will appear in more varied ways to create a convergence.

• Education of Primary School Mathematics
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• v.23 no.1
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• pp.27-44
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• 2020

In this study, we extracted geometrical learning content that is treated similarly in elementary and middle schools, and analyzed the differences between how this study is handled in elementary and middle schools. The analysis tools used in this study were developed by referring to the research results presented by Merrill. Merrill classified the study results into two dimensions: 'performance level' and 'content type', and 'teach station' and 'proposal type' by presenting the contents in the textbook. Based on this classification, this study was conducted. According to the results of the study, nine achievement criteria were extracted as learning factors that were treated similarly in elementary and middle schools. The extracted learning elements were systematically analyzed through analysis tools. The results of this study are expected to provide significant implications for the improvement of mathematics learning and for the improvement of new curricula.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.155-165
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• 2017

This study divides organizational citizenship behaviors into two dimensions, organizational and individual, in order to clarify the out-role behaviors of organizational members more specifically. In addition, we selected Empowering leadership as an input factor that can lead to organizational citizenship behavior and examined the mediating role of trust. To accomplish this purpose, the authors conducted a survey of employees in manufacturing companies in the Daegu-Gyeongbuk region and the hypothesis was verified through structural equations model. The results of the study are as follows. Empowering leadership has a significant positive impact on OCB-O and OCB-I. Also, Trust has been found to partial mediate effect the relationship between empowering leadership and OCB_O and OCB_I. The results of this study will be specific guidelines for inducing organizational citizenship behavior in organizations, and will further expand the scope of research into organizational citizenship behavior.

• The Journal of Advanced Prosthodontics
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• v.9 no.3
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• pp.200-207
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• 2017

PURPOSE. In this study, three bioceramic materials, [IPS Empress CAD (Ivoclar), IPS e.max CAD (Ivoclar), and Lava Ultimate CAD (3M ESPE)] were treated with three commercial mouthrinses [Listerine, Tantum Verde, and Klorhex]; and changes in colour reflectance and surface roughness values were then quantitatively assessed. MATERIALS AND METHODS. One hundred and twenty ceramic samples, with dimensions of $2{\times}12{\times}14mm$, were prepared and divided into nine sample groups, except three control samples. The samples were immersed in the mouthrinse solutions for 120 hrs, and changes in colour reflectance and surface roughness values were measured by UV light spectrophotometry (Vita Easyshade; VITA Zahnfabrik) and by profilometer device (MitutoyoSurftest SJ-301), respectively. The change of surface roughness was inspected by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). RESULTS. There was a positive correlation between the ${\Delta}E$ and increase in the surface roughness. Two of the ceramic materials, IPS Empress and Lava Ultimate, were affected significantly by the treatment of the mouthrinse solutions (P<.05). The most affecting solution was Tantum Verde and the most affected material was Lava Ultimate. As expected, the most resistant material to ${\Delta}E$ and chemical corrosion was IPS e max CAD among the materials used. CONCLUSION. This work implied that mouthrinse with lower alcohol content had less deteriorating effect on colour and on the surface morphology of the bioceramic materials.

• The Journal of Advanced Prosthodontics
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• v.10 no.1
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• pp.25-31
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• 2018

PURPOSE. The aim of the present study was to record the metal-ceramic bond strength of a feldspathic dental porcelain and a Co-Cr alloy, using the Direct Metal Laser Sintering technique (DMLS) for the fabrication of metal substrates. MATERIALS AND METHODS. Ten metal substrates were fabricated with powder of a dental Co-Cr alloy using DMLS technique (test group) in dimensions according to ISO 9693. Another ten substrates were fabricated with a casing dental Co-Cr alloy using classic casting technique (control group) for comparison. Another three substrates were fabricated using each technique to record the Modulus of Elasticity (E) of the used alloys. All substrates were examined to record external and internal porosity. Feldspathic porcelain was applied on the substrates. Specimens were tested using the three-point bending test. The failure mode was determined using optical and scanning electron microscopy. The statistical analysis was performed using t-test. RESULTS. Substrates prepared using DMLS technique did not show internal porosity as compared to those produced using the casting technique. The E of control and test group was $222{\pm}5.13GPa$ and $227{\pm}3GPa$, respectively. The bond strength was $51.87{\pm}7.50MPa$ for test group and $54.60{\pm}6.20MPa$ for control group. No statistically significant differences between the two groups were recorded. The mode of failure was mainly cohesive for all specimens. CONCLUSION. Specimens produced by the DMLS technique cover the lowest acceptable metal-ceramic bond strength of 25 MPa specified in ISO 9693 and present satisfactory bond strength for clinical use.

• Informatization Policy
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• v.21 no.3
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• pp.102-127
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• 2014

Although mobile banking provides cost-saving opportunities as well as convenient banking experience for customers, today's banks still face challenges when deploying the technology because a good number of customers are reluctant to use mobile banking for personal reasons. This paper is an empirical investigation of the determinants of the intention to use smartphone-based mobile banking services. The determinants are grouped into two categories including personal factors and social influence factors. We conducted an empirical analysis using 751 survey responses collected from present users of mobile banking services. The results of the analysis reveal that all the personal factors have positive relationships with the intention to use mobile banking services. On the other hand, it was found that of the social influence factors, perceived herding behavior has significantly positive relationship with the intention to use smartphone-based services, whereas subjective norm is not significantly related to the intention. We provide practical as well as academic implications of the research findings.

• Structural Engineering and Mechanics
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• v.67 no.5
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• pp.505-516
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• 2018

In this paper, the effects of particle size and model scale of concrete has been investigated on the failure mechanism of PFC2D numerical models under uniaxial compressive test. For this purpose, rectangular models with same particle sizes and different model dimensions, i.e., $3mm{\times}6mm$, $6mm{\times}12mm$, $12mm{\times}24mm$, $25mm{\times}50mm$ and $54mm{\times}108mm$, were prepared. Also rectangular models with dimension of $54mm{\times}108mm$ and different particle sizes, i.e., 0.27 mm, 0.47 mm, 0.67 mm, 0.87 mm, 1.07 mm, 1.87 mm and 2.27 mm were simulated using PFC2D and tested under uniaxial compressive test. Concurrent with uniaxial test, direct shear test was performed on the numerical models. Dimension of the models were $75{\times}100mm$. Two narrow bands of particles with dimension of $37.5mm{\times}20mm$ were removed from upper and lower of the model to supply the shear test condition. The particle sizes in the models were 0.47 mm, 0.57 mm, 0.67 mm and 0.77 mm. The result shows that failure pattern was affected by model scale and particle size. The uniaxial compressive strength and shear strength were increased by increasing the model scale and particle size.

• The Journal of Fisheries Business Administration
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• v.22 no.2
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• pp.19-51
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• 1991

The objectives of the study are to look into the fisheries processing industry, analyze problems the industry has, and develop strategies for the industry to take care of the problems. The study was performed in two different dimensions : industry level and firm level. Nevertheless, the study focused on the following main problem areas raw material, production, technology development, internationalization, and managerial performance. The secondary data were utilized to analyze problems at the industry level, For analyzing the firm level situation, an empirical study by using a mail survey with a questionnaire was accomplished. The main problems found were as follows : First, difficulty in procuring raw material was the most serious and main problem. It was caused, externally, by the announcement of 200 nautical miles by most of fishery abundant countries and, internally, by drying fishery resources in the nation's coastal areas ; Second, the rate of fishery processing has been continuously increased and the degree of the processing has also been sophisticated, which implies the pattern of demand for the fishery has been changing widely and deeply. The industry, however, seemed to be unable to meet the consumers' satisfaction ; Third, with the importance of technology for ensuring the changing demands in the fishery processing industry, there has been little effort in research and development both at industry level and at the firm level ; Next, the industry has mainly involved in exporting in association with internationalization. Not to mention about foreign direct investment, technology transfer was not active ; Finaliy, most of firms were densely located in a few areas. The managerical performance in terms of main financial ratios still needs to be improved. Thus, strategies, which would take care of the repective problems, were developed. At industry level, the strategies were developed by reasoning mostly based on the findings from the literature survey. A scheme for internationalization of the firms was suggested. This was made by extracting the factors which would differentiate the firms' internationalization stages. In order to achieve this analysis, discriminant approach was employed. Despite the utility of the findings, it was mostly emphasized that harmonious efforts among government, the industry supporting institutions such as banks, and firms are needed for the successful operation of the strategies. Also, a list of areas for further study was provided especially in relation to the validity threatening parts of the study.

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.237-240
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• 2005

We present images of L1551 IRS5 at angular resolutions as high as ${\~}$30 mas, corresponding to a spatial resolution of ${\~}$5 AU, made at 7 mm with the VLA. Previously known to be a binary protostellar system, we show that L1551 IRS5 is likely a triple protostellar system. The primary and secondary components have a projected separation of ${\~}$46 AU, whereas the tertiary component has a projected separation of ${\~}$11 AU from the primary component. The circumstellar dust disks of the primary and secondary components have dimensions of ${\~}$15 AU, whereas that of the tertiary component has a dimension of ${\~}$10 AU. Their major axes are closely, but not perfectly, aligned with each other, as well as the major axis of the surrounding flattened, rotating, and contracting molecular condensation (pseudodisk). Furthermore, the orbital motion of the primary and secondary components is in the same direction as the rotational motion of this pseudodisk. We suggest that all three protostellar components formed as a result of the fragmentation of the central region of the molecular pseudo disk. The primary and secondary components, but apparently not the tertiary component, each exhibits a bipolar ionized jet that is centered on and which emergers perpendicular to its associated dust disk. Neither jets are resolved along their base, implying that they are driven within a radial distance of ${\~}$2.5 AU from their central protostars. Finally, we show evidence for what may be dusty matter streams feeding the two main protostellar components.