• Journal of the Optical Society of Korea
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• v.13 no.1
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• pp.22-27
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• 2009

Target design study to improve the quality of an accelerated proton beam from the interaction of a high-intensity short pulse laser with an overdense plasma slab has been accomplished by using a two-dimensional, fully electromagnetic and relativistic particle-in-cell (PIC) simulation. The target consists of a thin core part and a thick peripheral part of equivalent plasma densities, while the ratio of the radius of the core part to the laser spot size, and the position of the peripheral part relative to the fixed core part were varied. The positive effects of this core-peripheral target structure could be expected from the knowledge of the typical target normal sheath acceleration (TNSA) mechanism in a laser-plasma interaction, and were apparently evidenced from the comparison with the case of a conventional simple planar target and the case of the transversal size reduction of the simple planar target. Improvements of the beam qualities including the collimation, the forward directionality, and the beam divergence were verified by detailed analysis of relativistic momentum, angular directionality, and the spatial density map of the accelerated protons.

• Journal of Korea Port Economic Association
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• v.23 no.4
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• pp.1-22
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• 2007

The present study examined the effects of the factors of port service quality on customer satisfaction and surveyed customers' perception on service quality and their satisfaction with port services by comparing Incheon Port with Qingdo Port, Tianjin Port and Dalian Port. According to the results, the quality of port services can be divided into three levels-inner quality, external environment quality and interaction quality, and except the external environment quality of the Dalian Port, the three levels of service quality were found to have significant effects on customer satisfaction. In addition, according to the results of comparing customers' perception on the three levels of service quality among the ports, the Incheon Port was inferior to the Qingdo Port, the Tianjin Port and the Dalian Port in inner quality, and to the Qingdo Port and the Tianjin Port in external environment quality, but superior to the Tianjin Port and the Dalian Port in interaction quality. However, customers' satisfaction with the Incheon Port was lower than that with the Qingdo Port and the Tianjin Port.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.6
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• pp.1707-1717
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• 2012

Digital textbooks, considered as core textbooks tailored to the abilities and interests of students, provide them with a combination of textbooks, reference books, workbooks, dictionaries and multimedia contents. In this paper, we employ a modified version of the Technology Acceptance Model(TAM), a model which has been widely used and empirically validated to explain why individuals use a particular information technology(IT). This paper proposes that additional variables, such as educational impacts, contents quality, interaction and enjoyment, enhance our understanding of behaviors of pilot school teachers in using multimedia-based digital textbooks as a substitute for traditional paper-version of textbooks. A structural equation model is employed with survey data from 157 pilot school teachers in pilot program supported by Korean government and KERIS(Korea Education & Research Information Service), to empirically assess the strength of the relationships in the proposed model. It is hoped that the results from this study provide meaningful insight into the development and delivery of high quality digital textbooks.

• The Journal of Information Systems
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• v.15 no.1
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• pp.97-119
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• 2006

As the electronic market grows, the vendors establish internet shopping mall with a plenty of electronic catalogs and prepare to respond rapid electronic market growth. Consequently, building attractable electronic catalogs is very important to give a customer satisfaction. Based on prior researches, this study suggest a research model to understand the factors of electronic catalogs and their impact on the customer's relationship quality. As a result, this study confirmed that accuracy, timeliness, interaction, presentation, and information structure of electronic catalog were important factors. Presentation is the most important factors of electronic catalog. Information structure and accuracy also heavily impact on user satisfaction. And their impact on the customer satisfaction and trust were proved to be substantial. These results will contribute to provide implicit guidelines to the developers of internet shopping malls.

• BMB Reports
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• v.56 no.6
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• pp.321-325
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• 2023

RNAs are pivotal molecules acting as messengers of genetic information and regulatory molecules for cellular development and survival. From birth to death, RNAs face constant cellular decision for the precise control of cellular function and activity. Most eukaryotic cells employ conserved machineries for RNA decay including RNA silencing and RNA quality control (RQC). In plants, RQC monitors endogenous RNAs and degrades aberrant and dysfunctional species, whereas RNA silencing promotes RNA degradation to repress the expression of selected endogenous RNAs or exogenous RNA derived from transgenes and virus. Interestingly, emerging evidences have indicated that RQC and RNA silencing interact with each by sharing target RNAs and regulatory components. Such interaction should be tightly organized for proper cellular survival. However, it is still elusive that how each machinery specifically recognizes target RNAs. In this review, we summarize recent advances on RNA silencing and RQC pathway and discuss potential mechanisms underlying the interaction between the two machineries.

• Asia Marketing Journal
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• v.25 no.3
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• pp.99-110
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• 2023

Chatbot services have become an essential communication tool for interacting with consumers in e-commerce. To understand consumer behavior in the context of chatbot services, we apply the Theory of Planned Behavior (TPB) to analyze continuance intention to use and additional predictors to explain behavioral intention. An analysis of data collected from 300 digital shopping users who had experienced chatbot services revealed that an extended TPB model holds for the continuous use of chatbot services, driven by both interaction and information quality. Accordingly, these ndings provide a better understanding of consumer behavior toward chatbot services and valuable insights into digital customer relationship management.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.57-69
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• 2014

This Study analyzed empirically how do brand value components of consumer perception side effect on receptive degree of product in extension types of vertical brand extension, and how does the difference of receptive degree among products of extension types be showed under the positive effect of brand value. First, brand awareness has positive effect on upward and downward extension, and receptive degree of product is higher in downward extension than upward extension. Second, brand association doesn't have positive effect on upward extension but has positive effect on downward extension. Third, perceived quality showed similar results to brand awareness. Only, receptive degree of upward extension product in high perceived quality is higher than in high brand awareness or in high brand association. Fourth, examining about interaction effect among brand value components, interaction effect between brand awareness and brand association exists in downward extension, interaction effect between brand awareness and perceived quality exists in upward and downward extension, and interaction effect between brand association and perceived quality exists in upward and downward extension. By this interaction effect, the difference of receptive degree among products of extension types grows larger.

• Korean Journal of Childcare and Education
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• v.16 no.6
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• pp.185-202
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• 2020

Objective: The purpose of this study is to analyze the mediating effect of teacher's ego resilience in the relationship between the social support of colleague teachers and teacher-child interaction. Methods: A survey was conducted on 181 teachers working at early childhood education institutions located in Gyeonggi and Chungbuk regions. The structural equation model was verified with the Mplus 6.0 program. Results: First, the social support of colleague teachers directly affects teacher's ego-resilience and teacher-child interaction, and teachers ego-resilience has a significant effect on teacher-child interaction. Second, the teachers ego-resilience was found to be partially mediated in the relationship between the social support of fellow teachers and teacher-child interaction. With bootstrapping, the mediating effect of teachers ego-resilience was found to be statistically significant between the social support of colleague teachers and teacher-child interaction. Conclusion/Implications: Social support of fellow teachers plays an important role in the positive expression of teacher-child interaction, and the quality of relationships with children can be further enhanced by promoting teachers ego-resilience that mediates the two variables.

• The Journal of Korean Physical Therapy
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• v.29 no.1
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• pp.7-15
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• 2017

Purpose: This randomized controlled trial was conducted to compare the effectiveness of global postural reeducation to segmental stretching in subjects with neck and shoulder pain. Methods: Sixteen subjects with neck and shoulder pain were randomized into two intervention groups, a global posture reeducation group (n=8) that performed muscle chain stretching, and a segmental stretching group (n=8) that performed conventional static muscle stretching. The intervention program consisted of two 40 minutes individual sessions per week for four weeks. Subjects were evaluated pre-intervention, two-week after intervention and at a four-week follow-up appointment for pain intensity, disability and health-related quality of life. Two-way repeated analysis of variance was used for between-time and between-group comparisons. The significance level was 0.05. Results: Significant pain relief and decreasing discomfort of the neck and shoulder were observed after intervention in both groups, and there was an interaction between time lapse and groups (pain, F=10.31, neck disability, F=25.45, shoulder disability, F=12.82, p<0.05). Quality of life also improved after intervention in both groups. Moreover, the physical components score improved, and a significant interaction was observed between time and groups (F=4.85, p<0.05). However, no significant improvement in mental component score of quality of life and no significant interaction between time and groups were observed (p>0.05). Conclusion: These findings suggest that a GPR intervention in subjects with neck and shoulder pain induces greater improvement of pain and disability and quality of life than segmental stretching.

• Safety and Health at Work
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• v.6 no.3
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• pp.240-248
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• 2015

Background: Recovery from fatigue is important in maintaining night workers' health. This study compared the course of self-reported recovery after 2-week 12-hour schedules consisting of either night shifts or swing shifts (i.e., 7 night shifts followed by 7 day shifts) to such schedules consisting of only day work. Methods: Sixty-one male offshore employees-20 night workers, 16 swing shift workers, and 25 day workers-rated six questions on fatigue (sleep quality, feeling rested, physical and mental fatigue, and energy levels; scale 1-11) for 14 days after an offshore tour. After the two night-work schedules, differences on the $1^{st}$ day (main effects) and differences during the follow-up (interaction effects) were compared to day work with generalized estimating equations analysis. Results: After adjustment for confounders, significant main effects were found for sleep quality for night workers (1.41, 95% confidence interval 1.05-1.89) and swing shift workers (1.42, 95% confidence interval 1.03-1.94) when compared to day workers; their interaction terms were not statistically significant. For the remaining fatigue outcomes, no statistically significant main or interaction effects were found. Conclusion: After 2-week 12-hour night and swing shifts, only the course for sleep quality differed from that of day work. Sleep quality was poorer for night and swing shift workers on the $1^{st}$ day off and remained poorer for the 14-day follow-up. This showed that while working at night had no effect on feeling rested, tiredness, and energy levels, it had a relatively long-lasting effect on sleep quality.