• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.211-221
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• 2006

Purpose The aims of this study were to evaluate micro-tensile bond strength of composite resin bonded to dentin following high-speed rotary handpiece preparation or Er:YAG laser preparation with two different adhesive systems and to assess the influence of different Er:YAG laser energies on the micro-tensile bond strength. Materials and Methods In this study, 40 third morlars were used. Flat dentin specimans were obtained and randomly assigned to eight groups. Dentin surfaces were prepared with one of four cutting types: carbide bur, Er:YAG laser (2 W, 3 W and 4 W) and conditioned with two bonding systems, Scotchbond Multipurpose Plus (SM), Clearfil SE bond (SE) and composite resin-build ups were created. After storage for 24 hours, each specimen was serially sectioned perpendicular to the bonded surface to produce more than thirty slabs in each group. Micro-tensile bond strength test was performed at a crosshead speed of 1.0 mm/min. Micro-tensile bond strengths (${\mu}TBS$) were expressed as means$\pm$SD. Data were submitted to statistical analysis using two-way ANOVA, one-way ANOVA, Student-Newman-Keuls' multiple comparison test and t-test. Results and Conclusion 1. Regardless of bonding systems, the ${\mu}TBS$ according to cutting types were from highest to lowest : 3 W, 2 W, Bur, and 4 W. In addition, there was no significant difference between Bur and 4 W (p<0.001). 2. Regardless of cutting types, SM showed significantly higher ${\mu}TBS$ than SE (p<0.001). 3. Bonding to dentin conditioned with SM resulted in higher ${\mu}TBS$ for 3 W compared to Bur, 2 W, and 4 W. There was no significant difference between 2 W and Bur (p<0.001). 4. Bonding to dentin conditioned with SE resulted in higher ${\mu}TBS$ for 3 W compared to 2 W, 4 W, and Bur. Bur exhibited significant lower ${\mu}TBS$ than all other cutting types. There were no significant differences between 3 W, 2 W and between 4 W and Bur (p<0.001). 5. The ${\mu}TBS$ of laser cutting groups were shown in order from highest to lowest: 3 W, 2 W and 4 W in two bonding systems. There was no significant difference between 2 W and 3 W in SE (p<0.001). : The ${\mu}TBS$ of composite resin bonded dentin was significantly affected by interaction between the cutting type and bonding system. In the range of 2 W-3 W, cavity preparation of the Er:YAG laser seems to supply good adhesion of composite resin restoration no less than bur preparation. In particular, if you want to use the self-etching system, including Clearfil SE bond for the purpose of a simplification of the bonding procedures and prevention of adverse effects by excessive etching, an Er:YAG laser may offer better adhesion than a bur.

• Asia pacific journal of information systems
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• v.24 no.3
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• pp.255-279
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• 2014

It is not too much to say that smartphones have become an essential part of our lives due to their versatility. Nevertheless, they still have less overall capabilities than their desktop counterparts. Specifically, they have small screens and low resolutions, which make their applications difficult to have a usable interface. To account for these limitations, the interface of smartphone applications should be designed carefully and properly. Good interface design to any application is critical. However, a comprehensive information systems (IS) literature review found that there has been little research on the user interface design of smartphone applications. More specifically, there has been little empirical evidence and understanding about how metaphors, an imaginative way of describing objects and concepts, in the user interface of smartphone applications affect users' intention to use the applications. Thereby, the research goals of this study are to examine 1) the effects of the metaphors in the user interface of smartphone applications on the interaction between users and applications and 2) the effects of mediating variables including the interaction between users and applications, users' beliefs and attitudes, on users' intention to use the applications. A survey was conducted to collect data. University students and practitioners participated in the survey. A 24-item questionnaire was developed on a 5-point Likert-type scale. The measurement items were mostly adapted from the previous studies in the IS literature and modified to fit the context of this study. First, a principal component factor analysis was performed to explore the inter-relationships among a set of variables. The analysis showed that most of the items loaded quite strongly on the six components. The analysis also revealed the six components with eigenvalues exceeding 1, explaining a total of 70.7 per cent of the variance. The reliabilities of the items were also checked. Most Cronbach alpha values were above 0.8, so the scales were considered reliable. In sum, the results of the analysis support the decision to retain the six factors for further investigation. Next, the structural model was analyzed with AMOS structural equation modeling. The values of GFI, AGFI, NFI, TLI, CFI, and RMSEA were checked. The values showed that the research model considerably have a good fit in general. Next, the convergent and discriminant validities of all constructs were examined. The values for the standardized regression weights and critical ration (CR) indicated sufficient convergent validity for all constructs. In addition, the square root of the average variance extracted (AVE) of each construct was compared with its correlations with all other constructs. The results supported discriminant validity for all constructs. In sum, the results of analysis demonstrated adequate convergent and discriminant validities for all constructs. Finally, path coefficients between the variables were examined. Methphor was found to have an impact on interaction (${\beta}$ = .457, p = .000). There were also significant effects of the interaction on perceived usefulness (${\beta}$ = .273, p = .000) and ease of use (${\beta}$ = .405, p = .000). User attitude was significantly influenced by these two beliefs, perceived usefulness (${\beta}$ = .386, p = .000) and ease of use (${\beta}$ = .347, p = .000) respectively. Further, the results of analysis found that users' intention to use smartphone applications was significantly influenced by user attitude (${\beta}$ = .567, p = .000). Based upon the analyses, all hypotheses were supported. This study found that the metaphors used in the interface of smartphone applications affect not only the interaction between users and applications, but also users' intention to use the applications through the mediating variables, perceived usefulness and ease of use. These findings imply that if the metaphors used in the user interface of application are easy enough to understand for smartphone users, then the application can be perceived useful and easy to use, which in turn make users to have an intention to use the application. In conclusion, this study contributed not only to validate and extend Technology Acceptance Model (TAM) partially, but also to develop the construct of metaphor in smartphone settings. However, since a single empirical study cannot be enough to validate the findings, some limitations should be considered.

• Journal of Distribution Research
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• v.16 no.2
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• pp.95-118
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• 2011

The purpose of this study is as follows. First, we investigate empirically the effects of social network properties such as social network density and centrality of a franchisee on its information sharing with various subjects such as the franchisor and other franchisees in the franchise system. Second, we examine exploratively if tie strength between a franchisee and its franchisor plays a moderating role on the relationship between social network properties and information sharing. The study model was established as shown in

• Journal of The Korean Association For Science Education
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• v.36 no.3
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• pp.457-470
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• 2016

We investigated the conceptual and methodological characteristics of self-study as an innovational way with reflective research methods and explored the possibility of application of self-study in the field of science education by reviewing previous researches done in foreign countries. The results show that Self-study in education means the study of self, self-practice, self-thought, and so on in the teaching and learning context. It is a kind of new research method to pursue the improvement of teaching and learning practice with integrated perspectives on the context of instruction, identities of members, their beliefs and values, innovation agenda for better education, etc. This can be attained by collective and critical reflection in doing research. Most previous articles on the methodology of self-study suggested that the self-study should be more than just daily journals written only by her/him self. To do self-study in the academic way, they requested interaction with critical and cooperative colleagues, multiple but strict qualitative research methods, and participants' efforts for making better practice in instruction. Similar features to the above are found in the previous 14 self-study papers related to science education done in foreign countries. Based on the results, we concluded that self-study could be applied usefully into the field of science education in Korea. This paper could contribute to stimulation in the innovation of science instruction in a more practical way by increasing the attention to self-study and provoking its practice in Korea.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.154-166
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• 2016

This study aims to contribute to better understanding the effects of the changes in the parameter values of GroundFilter algorithm(GF), which performs filtering process, and of GridsurfaceCreate algorithm(GC), which creates regular grid, provided in Fusion software on the accuracy of elevation of the final LiDAR-DEM products through comparative analysis. In order to test whether there are significant effects on the accuracy of the final LiDAR-DEM products due to the changes of GF(1, 3, 5, 7, 9) parameter levels and GC(1, 3, 5, 7, 9) parameter levels, two-way ANOVA is conducted based on residuals. The residuals are calculated using the differences between each sample plot's paired field-measured and DEM-derived elevation values given each individual GF and GC level. After that, Tukey HSD test is conducted as a post hoc test for grouping the levels. As a result of two-way ANOVA test, it is found that the change in the GF levels significantly affects the accuracy of LiDAR-DEM elevations(F-value : 27.340, p < 0.01), while the change in the GC levels does not significantly affect the accuracy of LiDAR-DEM elevations(F-value : 0.457). It is also found that the interaction effect between GF and GC levels is not likely to exist(F-value : 0.247). From the results of the Tukey HSD test in the GF levels, GF levels can be divided into two groups('7', '5', '9', '3' vs '1') by the differences of means of residuals. Given the current conditions, LiDAR-DEM can achieve the best accuracy when the level '7' and '3' are given as GF and GC level, respectively.

• Journal of the Korean Society of Costume
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• v.59 no.5
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• pp.167-179
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• 2009

The purposes of this study were to explore the influence on fashion brand image and brand loyalty according to fit of the fashion brand with cultural art field, motivation in culture marketing of the apparel company, and involvement of the consumers in art activities. The subjects ware 274 male and female in 20s and 30s living in Seoul and Gyeonggi area. The study was obtained through the use of an experimental design which was $2{\times}[2{\times}2]$ mixed factorial design. The summary main results were as follows. First, as far as the effect of the three variables on the social contribution image of the fashion brand, the results of the 3-way interaction are positive. Second, as far as the effect of the three variables on the product image of the fashion brand, the data suggests that only the main-effect of motivation in culture marketing of the apparel company is meaningfully positive. Third, as far as the effect of the three variables on fashion brand loyalty, both fit of the fashion brand with cultural art field and involvement of the consumers in art activities variables show positive results.

• Journal of Fashion Business
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• v.13 no.6
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• pp.76-88
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• 2009

This study has the purposes to search the most visually effective and appropriate number of pleats and skirt length, when it's worn, with the changes in the number of pleats and skirt length that could be influential in analyzing the visual evaluation of pleats skirt and to analyze the changes when those factors are applied in real pattern. The stimuli were 18 samples: 6 variations of the number of pleats and 3 variations of the length of skirt. The data were obtained from 54 fashion design majors. The data were analyzed by Factor Analysis, Anova, Scheffe's Test and the MCA method. The results of the study were as follows: The visual image by the number of pleats and the length of skirt were composed of 4 factors : activity, attraction, neatness and commonness. In these factors, activity factor was estimated by the most important factor. The visual image according to the changes in the number of pleats and skirt length had significant differences, and the pleats skirts with 12 and 16 number of pleats and 38cm of skirt length were evaluated to be the most effective. The activity factor had interaction influence effect according to the number of pleats and the skirt length. The skirt length had more influence than the number of pleats in attraction and neatness factors, and the other way around for commonness factor.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3338-3342
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• 2012

Covalent functionalization of a $B_{12}N_{12}$ nano-cage with $CO_2$ molecule has been investigated using density functional theory in terms of energetic, geometric, and electronic property analyses. Results show that besides two physisorption configurations, $CO_2$ preferably tends to perform [2+2] addition on B-N bonds of the cluster which are shared between six-membered and four-membered rings, releasing energy of 14.99 kcal/mol for adsorption of the first $CO_2$ and of 15.45 kcal/mol for the second one (per each molecule). On the basis of calculated density of states, we have found that the electronic properties of the physisorbed $B_{12}N_{12}$ by $CO_2$ have not changed, while slight changes have been predicted in the functionalized cases. Present results might be helpful to provide an effective way to modify the $B_{12}N_{12}$ properties for further purifications and applications.

• Phonetics and Speech Sciences
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• v.5 no.1
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• pp.39-46
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• 2013

This study examined the effects of phonetic complexity and articulatory severity on Percentage of Correct Consonant (PCC) and speech intelligibility in adults with dysarthria. Speech samples of thirty-two words from APAC (Assessment of Phonology and Articulation of Children) were collected from 38 dysarthric speakers with one of two different levels of articulatory severities (mild or mild-moderate). A PCC and speech intelligibility score was calculated by the 4 levels of phonetic complexity. Two-way mixed ANOVA analysis revealed: (1) the group with mild severity showed significantly higher PCC and speech intelligibility scores than the mild-moderate articulatory severity group, (2) PCC at the phonetic complexity level 4 was significantly lower than those at the other levels and (3) an interaction effect of articulatory severity and phonetic complexity was observed only on the PCC. Pearson correlation analysis demonstrated the degree of correlation between PCC and speech intelligibility varied depending on the level of articulatory severity and phonetic complexity. The clinical implications of the findings were discussed.

• Asia pacific journal of information systems
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• v.10 no.3
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• pp.159-180
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• 2000

As the importance of electronic commerce(EC) increases, some people argue that traditional commerce(TC) will ultimately give way to EC in the near future. Regardless of the type of commerce, however, it is the value factors of the customer that would formulate the direction of change in the market. This study investigates the influence of those value factors upon the attitude towards the type commerce and the repurchase intention of products and service. It also addresses the impact of the customer's risk disposition and level of confidence. A number of customer's value factors are hypothesized to affect the attitude, and the attitude in turn is expected to be related to the repurchase intention. Based on two hundred and ninety responses from the computer survey, the hypotheses are tested. The convenience, cost reduction, and information satisfaction factors affect EC attitude and repurchase intention. Similarly, the reliability, personal interaction, and shopping enjoyment factors affect TC attitude and repurchase intention. The comparison between EC and TC factors indicates the significant difference in the time saving factor in favor of EC. The personal characteristics such as risk disposition and level of confidence also influence the attitude and repurchase intention. The implications and limitations of this study are discussed. The value factors identified in this study may serve as important checklists for those firms already in EC and those intending to enter the market.