• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.208-221
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• 2007

The fracture toughness test is believed as a clinically relevant method for assessing the fracture resistance of the dentinal restoratives. The objectives of this study were to measure the fracture toughness $(K_{1C})$ and microtensile bond strength of dentin-resin composite interface and compare their relationship for their use in evaluation of the integrity of the dentin-resin bond. A minimum of six short-rod specimens for fracture toughness test and fifteen specimens for microtensile bond strength test was fabricated for each group of materials used. After all specimens storing for 24 hours in distilled water at $37^{\circ}C$, they were tensile-loaded with an EZ tester universal testing machin. Statistical analysis was performed using ANOVA and Tukey's test at the 95% confidence level, Pearson's coefficient was used to verify the correlation between the mean of fracture toughness and microtensile bond strength. FE-SEM was employed on fractured surface to describe the crack propagation. Fracture toughness value of Clearfil SE Bond (SE) was the highest, followed by Adper Single Bond 2 (SB), OptiBond Solo (OB), ONE-STEP PLUS (0S), ScotchBond Multi-purpose (SM) and there was significant difference between SE and other 4 groups (p < 0.05). There were, however, no significant difference among SB, OB, OS, SM (p > 0.05). Microtensile bond strength of SE was the highest, followed by SB, OB, SM, OS and OS only showed significant lower value (p < 0.05). There was no correlation between fracture toughness and microtensile bond strength values. FE-SEM examination revealed that dentin bonding agent showed different film thickness and different failure pattern according to the film thickness. From the limited results of this study, it was noted that there was statistically no correlation between K1C and ${\mu}TBS$. We can conclude that for obtaining the reliability of bond strength test of dentin bonding agent, we must pay more attention to the test procedure and its profound scrutiny.

• The Journal of Society for e-Business Studies
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• v.27 no.2
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• pp.105-135
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• 2022

As COVID-19 has led to a surge in e-commerce Buy Now Pay Later(BNPL) has become preferred choice among millennials. In Korea Coupang followed by Naver Pay offers a deferred payment, aiming to create customer lock-in effect, save credit card processing fee and lay the groundwork for entering into new financial services. However the literature related to the influential factors of customers' usage intention toward a deferred payment is scarce. For the study, a multi-group analysis was carried out to find differences between Naver shopping and Coupang. The results revealed that the important factors that affect a deferred payment adoption were compatibility, impulsive buying tendency in Naver shopping, whereas compatibility, relative advantage, additional value in Coupang(listed in order of most important). In addition, impulsive buying tendency had a positive effect on adoption intention in Naver shopping and on perceived risk in Coupang. The results imply that Naver shopping need to focus on managing delinquency while Coupang should provide sufficient information on how late fees and credit rating downgrade work and try not to make a deferred payment option stand out. In order to increase adoption rate it is recommendable to narrow down target segment of a deferred payment and expand it to a specialized vertical such as travel.

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.172-185
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• 2020

To explore the impact of restaurant service quality for foreigners in South Korea on customer satisfaction, customer trust, and loyalty from three dimensions: quality of physical environment, food quality, and service quality and the influence of perceived price on satisfaction and loyalty, a survey was conducted by collecting 202 valid questionnaires and Amos 23 was used to examine the relationships between variables. The results show that the quality of physical environment, food quality, and service quality have significant positive effects on customer trust, but only food quality has a significant effect on customer loyalty and all three have no significant effects on customer satisfaction. In addition, customer trust has a significant positive effect on customer satisfaction and customer loyalty, but the effect of customer satisfaction on loyalty has not been verified in this study. At the same time, perceived price has a significant positive effect on customer satisfaction, but no significant effect on customer loyalty. Then the study examined the moderating effect of gender by using the SEM multi-group analysis method, founding that there are no significant differences between male and female on the impact of the three dimensions of restaurant service quality on customer satisfaction, and no significant differences between male and female on the impact of perceived price on customer satisfaction and customer satisfaction on loyalty, meaning that gender's moderating effects are not valid. These conclusions of this study are useful for restaurant operators to improve the quality of the physical environment, food quality and service quality, effectively improve customer trust, and thus customer satisfaction and loyalty.

• The KIPS Transactions:PartD
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• v.16D no.1
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• pp.43-54
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• 2009

The purpose of this study is to explore variables that affect users' perceived value of mobile advertising and actual response intention and to analyze causal relationships among variables. In order to verify the relational significance, we built new research model and hypotheses based on the Ducoffe's model(1996). And we found out four independent variables such as entertainment, information usefulness, convenience, economical efficiency, and advertising impact's value as a mediating variable. Especially, we classified into four multi-age groups to investigate properly moderating effects through SEM(path analysis) and difference test. Therefore, it is academical and practical worth that we developed our model to appropriate on mobile advertising's unique property and that we verified our hypotheses and variables focused on age group, whereas previous research did not. For this, we surveyed 345 samples for conducting structural equation modeling in empirical approach. The results of this study supported the statistical significance of all hypotheses except but convenience.

• Journal of Korea Trade
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• v.25 no.7
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• pp.75-91
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• 2021

Purpose - Social commerce (SC) is the growth of social media highlighting the e-commerce transactions and currently, the greatest challenges of e-commerce have attracted the influence of trust in social commerce intention (SCI). Based on the challenge, the study's purpose is to discover the effect of social support (informational and emotional support) on the SCI. The study also explores the mediation effect of trust and the moderation impact of culture between the USA and Korea. Design/methodology - This study used a sample of 482 surveys filled out by online shoppers from the US and Korea, two countries with divergent cultural values. Structural equation modelling (SEM) is used to analyze the hypothetical paths. In addition, bootstrapping and multi-group analysis are perform to view mediation and moderation effects respectively. Findings - The results of our study shows that both informational and emotional support significantly influences trust and SCI. Our results also supports the mediating effect of trust in social support and the moderating effect of culture in forming SCI. Originality/value - Our empirical results provide important information to businesses formulating cross-cultural SC strategies. This will help SC companies to analyze the aspects of customer trust through social support, which in turn will increase SCI and thereby established a competitive position for SCs. Our results will also be holistic directions for SC vendors in cross-cultural settings, which will offer important social and economic contributions to the sustainable growth of SC's business.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.5
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• pp.1004-1018
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• 2020

Advances in e-commerce enable consumers to shop efficiently for fashion products in global markets in addition, the market size of purchasing directly from foreign websites are also increasing. This study investigates the effects of hedonic and utilitarian shopping values on the continuous use intention of online cross-border shopping. Curiosity and self-efficacy were introduced as mediating variables between shopping values and user intentions. A web-based survey is conducted on female consumers, who have experiences to buy fashion products by online cross-border shopping. A total of 472 responses were collected from a panel of online survey firms. Data are analyzed using confirmatory factor analysis, structural equation modeling, and multi-group SEM by AMOS 21.0. According to the results of the structural equation model test, hedonic value affected continuous use intention of online cross-border shopping as mediated by curiosity and self-efficacy; in addition, utilitarian value influenced self-efficacy, which mediated relations between the utilitarian value and the continuous use intention. The research model was also tested to compare heavy users and light users of online cross-border shopping. For heavy users, the effect of hedonic value on curiosity was significantly stronger than for light users. Several implications are suggested based on the results.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.3
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• pp.464-480
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• 2022

With the steady development of Artificial Intelligence (AI), online stores are adopting chatbot services as virtual shopping assistants. This study proposes the concept of para-social presence to explore the undiscovered role of fashion chatbots' emotional and relational characteristics on service acceptance. Based on the Technology Acceptance Model (TAM), this study investigates the effect of a chatbot's para-social presence on service acceptance intention through consumers' beliefs. The web-based experiment was conducted on adult consumers who experienced chatbot services in an online shopping situation. A total of 247 responses were analyzed using confirmatory factor analysis, structural equation modeling, and multi-group SEM by AMOS 21.0 and SPSS 23.0. The findings illustrate that the chatbot's intimacy positively influenced consumers' perceived enjoyment, while the chatbot's understanding had a significant effect on perceived usefulness and ease of use. The chatbot's involvement had a positive effect on all consumer beliefs. Moreover, perceived ease of use had a positive influence on usefulness. A greater level of perceived usefulness and enjoyment positively heightened consumers' service acceptance intention. This study also verifies the moderating role of a need for human interaction. Consumers with a high need for human interaction have a relatively low tendency to perceive chatbot services as useful.

• 한국노년학
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• v.38 no.3
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• pp.645-666
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• 2018

The purpose of this study is to investigate the characteristics of the elderly with disability focused on comparison between aging with disability and disability with aging in Korea. Disability in older age has been related to several psychosocial characteristics, including social support, self-esteem, life satisfaction and depression. However, the exact role of these characteristics in the disablement process remains uncertain and this study focused on comparison between aging with disability and disability with aging in Korea. This study analyzed the 12th wave (2017) KWPS(Korean Welfare Panel Study)and Disability Study which included 692 elderly with disability aged 65 and over. The data were processed by SEM and multi-group SEM analysis. The findings were as follows; First, family support and the significant others support showed direct effects on the life satisfaction of the elderly with disability. Second, family support and the significant others support reduced the level of depression and enhanced self-esteem and finally impact on the life satisfaction of the elderly with disability. The formal support enhanced the depression and reduced self-esteem and eventually reduced the life satisfaction. Third, the disability with aging group showed more higher perception and more experience of formal support and formal service and more higher depression than the aging with disability group. Forth, the significant others support on life satisfaction only showed significance in disability with aging group and depression had significance in disability with aging group. Finally, aging with disability group showed positive effects on the formal support of life satisfaction but showed negative effects on the depression and self-esteem. Based on these findings, practical implications of future directions for research are discussed.

• Korean Journal of Health Education and Promotion
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• v.30 no.3
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• pp.59-73
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• 2013

Objectives: The study is aimed at examining the individual reasons and regional/environmental factors of online search on suicide using social big data to predict practical behaviors related to suicide and to develop an online suicide prevention system on the governmental level. Methods: The study was conducted using suicide-related social big data collected from online news sites, blogs, caf$\acute{e}$s, social network services and message boards between January 1 and December 31, 2011 (321,506 buzzes from users assumed as adults and 67,742 buzzes from those assumed as teenagers). Technical analysis and development of the suicide search prediction model were done using SPSS 20.0, and the structural model, nd multi-group analysis was made using AMOS 20.0. Also, HLM 7.0 was applied for the multilevel model analysis of the determinants of search on suicide by teenagers. Results: A summary of the results of multivariate analysis is as follows. First, search on suicide by adults appeared to increase on days when there were higher number of suicide incidents, higher number of search on drinking, higher divorce rate, lower birth rate and higher average humidity. Second, search on suicide by teenagers rose on days when there were higher number of teenage suicide incidents, higher number of search on stress or drinking and less fine dust particles. Third, the comparison of the results of the structural equation model analysis of search on suicide by adults and teenagers showed that teenagers were more likely to proceed from search on stress to search on sports, drinking and suicide, while adults significantly tended to move from search on drinking to search on suicide. Fourth, the result of the multilevel model analysis of determinants of search on suicide by teenagers showed that monthly teenagers suicide rate and average humidity had positive effect on the amount of search on suicide. Conclusions: The study shows that both adults and teenagers are influenced by various reasons to experience stress and search on suicide on the Internet. Therefore, we need to develop diverse school-level programs that can help relieve teenagers of stress and workplace-level programs to get rid of the work-related stress of adults.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.416-434
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• 2022

This study, for learners using online and offline tools, understood the structural relationship of user experience of smart learning app on continuous use intention through the technology acceptance model, and classified the learning type characteristics. In addition, based on the experience of using the smart learning app, we explored ways to improve the design of the user experience design for learning tools and contents. For this purpose, the usage perception of 84 middle and high school students of the developed smart learning learning app was investigated after using it for 2 months, and the data were analyzed using the PLS structural equation technique. The main results of this study are as follows. First, system and content user experience had a significant effect on perceived usability and perceived ease of use, and the effect on continued use intention through attitude was significant. Second, there was a significant difference in the effect of system user experience on perceived usefulness in multi-group comparative analysis and gender group. In the preferred learning group, it was the path from perceived ease of use and perceived usefulness to attitude and intention to continue using that showed a significant path difference. Third, as a result of classifying the most commonly used learning types by the multidimensional scale method, the types separated into low dimensions were found to be four types: offline sync type, online sync type, ubiquitous learning type, and self-direct learning type.