• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.401-405
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• 2004

Undoped SrB $i_2$T $a_2$O$_{9}$, donor-doped Sr$_{0.99}$B $i_2$(Ta$_{0.99}$W$_{0.01}$)$_2$O$_{9}$ and acceptor-doped SrB $i_2$(Ta$_{0.99}$Ti$_{0.01}$)$_2$O$_{8.99$ ceramics were prepared and their microstructure, ferroelectric P-E hysteresis and Curie temperature were investigated. Grain size did not influence P-E hysteresis curve in undoped SrB $i_2$T $a_2$O$_{9}$ ceramics. Donor-Doped Sr$_{0.99}$B $i_2$(Ta$_{0.99}$W$_{0.01}$)$_2$O$_{9}$ ceramics showed more saturated P-E hysteresis curve with larger remanent polarization (P$_{r}$) than undoped SrB $i_2$T $a_2$O$_{9}$ ceramics while acceptor-doped SrB $i_2$(Ta$_{0.99}$Ti$_{0.01}$)$_2$O$_{8.99}$ ceramics led to a pinched P-E hysteresis loop. Larger polarization in donor-doped Sr$_{0.99}$B $i_2$(Ta$_{0.99}$W$_{0.01}$)$_2$O$_{9}$ ceramics resulted from easier domain wall motion by Sr-vacancies.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.73-82
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• 2008

Dental caries is an infectious disease caused by mutans streptococci, and is a primary etiologic agent of dental caries in humans. The molecular pathogenesis of mutans streptococcal-associated dental caries occurs in three phases. Firstly, S. mutans attaches to tooth surface via a cell surface adhesion termed antigen I/II. In the second phase, the glucosyltransferase(GTFs) synthesize polymers like glucans in the presence of sucrose. In the third phase, the multivalent glucans interacts with glucan binding proteins (GBPs) and they make dental plaque and accumulation of microorganisms. Many studies and clinical trials have indicated that a mucosal immune response to these antigens(Ag I/II, GTFs, GBPs) of S. mutans can influence the pathogenesis of dental caries. So these antigens can be important vaccine candidates for immunologic intervention against dental caries. In this study, we cloned the genes for GTFb, GTFc, GTFd from S. mutans GS-5 and did the nucleotide sequence analysis. And the recombinant proteins of GTFd and N-terminus of GTFd were expressed. Intact GTF which we get from this experiment can be used for antibody production specific for any GTF activity domain through animal experiment.

• Journal of the Korean Society of Costume
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• v.56 no.3 s.102
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• pp.1-11
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• 2006

Che Guevara spearheading the Cuban Revolution was not only the icon as the revolutionary to the New-leftists of the 1960s advocating the ideology of Marxism but, as the cultural revolutionary, had a tremendous influence on the younger generation living in the digital age Che Guevara take on a figure of both the symbol of the Leftist but the romantic revolutionary because he had the external features such as black beret, red stars, military upper jackets and trousers, beard and pipe tobacco. In fact, the symbolic image of Che Guevara was made as the popular image by the avantgarde artists and political vanguard forces of the times under the necessity of Cuban government. Afterwards, the image of Che Guevara has been patronized in making people of aware of the resistant and revolutionary image to capital, power and the power of the media and symbolized as the resistant image to the American capital as well as the revolutionary guerrilla. And his image has continued to be reproduced and symbolized for the commercial and political purposes and as the enthusiastic image of youth culture. This can be seen as having been created as a new image by the popular culture formed by the development of the cyber culture and mass media in the cyberspace shaped by contemporary 'N' generations. The use of Che Guevara's symbolic image was made in the fashion field as well as in the cultural and artistic circles. The borrowing of the icon of Che Guevara represented in a fashion field is attributed to his free spirit, and it can be seen that fashion exists as the vehicle for representing both the symbol system and the sign system containing ideologies and texts as the communicator of resistance to the regime and to social issues. Therefore, this study attempted to investigate the commercial iconization of Che Guevara in the 1990s by comparing the ideology of the symbol in the 1960s and the 1990s and inquire into the borrowing of his image by the fashion domain as well as the fashion worn by him by reference to domestic books and materials on the fashion site. Thereby, this study attempted to make clear that the borrowing of Che Guevara in the realm of fashion since the 1990s not only contained the meaningful interpretation as the symbolic code in the culture of young people living in a digital era but fashion performs an intervening role in the cultural phenomenon.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.129-146
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• 2010

System response times(SRTs) are getting important while increasing the function of system. In the past, most research studied SRTs on situation of computer usage. There are lacking the research on simple domain. This study focuses on behavioral and emotional effect on situation of cell phone usage(experience 1; independent variables: degree of SRTs, dependent variables: behavioral and emotional evaluation). And this study investigates the behavioral and emotional effect in same SRTs on different situation(experience 2; independent variables: degree of SRTs, usage mode, dependent variables: behavioral and emotional evaluation, stress, mental strain). The result indicated that long SRTs increased problem solving time and negative emotion. User evaluated the system differently according to usage mode after they performed the same task. In other word, if user had a strong goal, then they felt more negative emotion and mental effort than the user don't have a strong goal. In the goal mode group, it was important there are being of delay or not. This study demonstrated that SRTs and usage mode influence user's emotion and behavior performance in same task.

• Tuberculosis and Respiratory Diseases
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• v.75 no.4
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• pp.140-149
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• 2013

Background: Plasminogen activator inhibitor type 1 (PAI-1), an important regulator of plasminogen activator system which controls degradation of extracellular membrane and progression of tumor cells, and PAI-1 gene polymorphic variants have been known as the prognostic biomarkers of non-small cell lung cancer patients. Recently, experimental in vitro study revealed that transforming growth factor-${\beta}1$ initiated PAI-1 transcription through epithelial growth factor receptor (EGFR) signaling pathway. However, there is little clinical evidence on the association between PAI-1 A15T gene polymorphism and prognosis of Korean population with pulmonary adenocarcinoma and the influence of activating mutation of EGFR kinase domain. Methods: We retrospectively reviewed the medical records of 171 patients who were diagnosed with pulmonary adenocarcinoma and undergone EGFR mutation analysis from 1995 through 2009. Results: In all patients with pulmonary adenocarcinoma, there was no significant association between PAI-1 A15T polymorphic variants and prognosis for overall survival. However, further subgroup analysis showed that the group with AG/AA genotype had a shorter 3-year survival time than the group with GG genotype in patients with EGFR mutant-type pulmonary adenocarcinoma (mean survival time, 24.9 months vs. 32.5 months, respectively; p=0.015). In multivariate analysis of 3-year survival for patients with pulmonary adenocarcinoma harboring mutant-type EGFR, the AG/AA genotype carriers had poorer prognosis than the GG genotype carriers (hazard ratio, 7.729; 95% confidence interval, 1.414-42.250; p=0.018). Conclusion: According to our study of Korean population with pulmonary adenocarcinoma, AG/AA genotype of PAI-1 A15T would be a significant predictor of poor short-term survival in patients with pulmonary adenocarcinoma harboring mutant-type EGFR.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.6
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• pp.83-98
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• 2016

This study investigated the effects of corporate entrepreneurship awareness on organizational effectiveness using a case study of a domestic public institution-something that had not been done before. The main purpose of this study was to examine the correlation between corporate entrepreneurship and the personal entrepreneurship of each organization member. Specifically, we studied the effects of four aspects of corporate entrepreneurship-innovation, risk sensitivity, goal orientation, and autonomy-on the effectiveness of the organization with regard to personal entrepreneurship, defined by creativity, job satisfaction, and organizational commitment, in a public institution. We examined the mediating role of the facets of private entrepreneurship-innovation, risk sensitivity, and goal orientation-on the effectiveness of organizations. In addition, we examined the correlation between the recognition of an organization and individual innovation, creativity, and entrepreneurship in domestic public institutions. We found that corporate entrepreneurship significantly influences organizational effectiveness. We also found that private entrepreneurship has partially influenced organizational effectiveness. This result indicates that specifically personal entrepreneurship in a public organization with a corporate structure contributes in part to organizational effectiveness. Therefore, the efforts made for disruptive innovation and the innovative strategies of corporates with personal entrepreneurship should be kept up for the long haul in order to influence the achievements of organizations in the public sector significantly. The need of the hour is for public institutions to disseminate and extend entrepreneurship at the national level. Furthermore, studies on corporate entrepreneurship in different fields in organizations in the public domain are needed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.2
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• pp.75-90
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• 2015

As soil nails support a ground by the friction between nails and soils being reinforced, the length of soil nails is important factor for a ground stability. Thus, the soil nail length has to be accurately evaluated in order to secure a ground stability. The goal of this study is to suggest the applicability of the non-destructive method as the basic research for the evaluation of the soil nail length. First, the elastic and electromagnetic waves are adopted to select an applicable method for the soil nails connected by the coupler. Test results show that while the ultrasonic waves are not detected due to the coupler, the electromagnetic waves are free for the influence of the coupler. Second, electromagnetic waves are measured for combined soil nails with the length of 1 m~15 m for the investigation of the characteristics of electromagnetic waves. The travel time of the electromagnetic wave increases with an increase in the soil nail length. In addition, the ground cable is used to apply the electromagnetic waves to pre-installed soil nails. Test results show that the travel time of the electromagnetic wave by using the ground cable increases with an increase in soil nail length. This study demonstrates that the electromagnetic wave may be a promising method for the evaluation of the soil nail length.

• Polymer(Korea)
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• v.29 no.4
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• pp.403-407
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• 2005

In this work, the solid polymer electrolyte (SPE) composites, which are composed of poly(ethylene oxide) (PEO), mesoporous mobil crystalline material-41 (MCM-41), and lithium salt, are prepared in order to investigate the influence of MCM-41 contents on the ionic conductivity of the composites. The crystallinity of the SPE composites was evaluated using differential scanning calorimeter (DSC) and X-ray diffraction (XRD). The ionic conductivity of the SPE composites was measured by the frequency response analyzer (FRA). As a result, the addition of MCM-41 into the polymeric mixture prohibited the growth of PEO crystalline domain due to the mesoporous structures of the MCM-41. The $P(EO)_{16}LiClO_4$/MCM-41 electrolytes show an increased ion conductivity as a function of MCM-41 content up to 8 $wt\%$ and a slightly decreased conductivity over 8 $wt\%$. These ion conductivity characteristics are dependent on a change of polymer crystallinity in the presence of MCM-41 system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.413-427
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• 1991

Variability of sea levels at Mukho and Ullungdo and sea level difference(SLD) associated with current is investigated. Time series of adjusted sea levels at both places have very similar pattern of change. Two components appear to contribute to the correlation between sea level and SLD. Low frequency thermosteric effect causes the sea level to rise and fall at the same time. Geostrophic effect of major currents is responsible for the sea level change in opposite ways at both sides. Two contributions have a cancelling effect for sea level change at Mukho while they are additive at Ullungdo. Characteristics of time series in frequency domain are divided into two parts with respect to 0.01 cycles per day(cpd). At Mukho, the cancelling effect yields small values of coherence for low-frequency bands whereas the dominant geostrophic influence may be responsible for the phase relations of about $\pm 180^{\circ}$ between sea level and SLD at higher frequency. Bimonthly dynamic height difference(DHD) between Mukho and Ullungdo is very significantly correlated with SLD. This result suggests that DHD thus the average velocity of current through the Mukho-Ullungdo section can successfully be diagnosed by the sea level records at both locations. For the annual variations, maximum SLD occurs at Mukho-Ullungdo section about 40 days later than the Korea Strait.

• School Mathematics
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• v.16 no.1
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• pp.157-180
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• 2014

This study investigated relationships between academic stress and mathematics learning motivation focusing on the mediating effect of academic motivation types. It also tested differential structural relationship among the variables in the high vs. low academic achievement level groups and the boys vs. girls of middle schools. The participants were 952 second graders from five middle schools. Student scores from the standardized tests that were developed to assess the students' academic stress, mathematics learning motivation, and three types of motivation (amotivation, controlled motivation, and autonomous motivation) were used in this study. The results demonstrate that there were significant differences in the relationship patterns of the research variables. Correlation analysis provided evidences that academic stress was negatively related with mathematics learning motivation and autonomous motivation but positively related with amotivation and controlled motivation. Also, mathematics learning motivation was negatively related with amotivation and controlled motivation but positively related with autonomous motivation. Structural equation modelling analysis provided the evidence that the full mediation model was a significant, in that the students' types of academic motivation mediated the effect of academic stress on mathematics learning motivation. Multiple group analysis revealed that there were group differences in the path coefficients of the structural model. But the academic stress showed negative influence on the mathematics learning motivation via amotivation and autonomous motivation in all groups.