• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1435-1440
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• 2013

To investigate the influence of the carbon matrix on the electrochemical performance of Si/C composites, four types of Si/C composites were prepared using graphite, petroleum coke, pitch and sucrose as carbon precursors. A ball mill was used to prepare Si/C blends from graphite and petroleum coke, whereas a dispersion technique was used to fabricate Si/C composites where Si was embedded in disordered carbon matrix derived from pitch or sucrose. The Si/pitch-based carbon composite showed superior Si utilization (96% in the first cycle) and excellent cycle retention (70% after 40 cycles), which was attributed to the effective encapsulation of Si and the buffering effect of the surrounding carbon matrix on the silicon particles.

• Asia pacific journal of information systems
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• v.30 no.1
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• pp.167-187
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• 2020

College students experience more cyber bullying than youth and cyber bullying on college students may be more harmful than youth. But many studies of cyber bullying have been conducted in youth, but little has been studied for college students. Therefore, this study investigated the negative effects of college students' cyber bullying experience on cognitive processing ability and emotional states. The social support of friends has a buffering effect that prevents stress and reduces the influence on external damage in stressful situations. But the impact of parental social support is controversial. Traditionally, the social support of parents has been claimed to mitigate the negative effects of external damage. Recently, however, it has been argued that parental social support, without considering the independence and autonomy needs of college students, does not alleviate the negative effects. Therefore, this study examined how the social support of friends and parents moderate the negative impact of cyber bullying. The results show that the more college students experience cyber bullying, the lower their cognitive processing ability and emotional states. And, the higher the social support of friends, the lower the harmful impacts of cyber bullying on cognitive processing ability and emotional states. But, the higher the social support of parents, the higher the harmful impacts of cyber bullying on cognitive processing ability and emotional states.

• Stress
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• v.26 no.4
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• pp.340-349
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• 2018

Background: The purpose of this study was to examine the moderating effect of resilience and social support to analyze that call center consultants' emotional labor impacts on the burnout. Methods: A survey questionnaire was conducted to people who work at call center in Gwangju and Deagu. The data from 444 were analyzed. Results: The result from the hierarchical multiple regression is as follows. First, deep acting decreased burnout, but surface acting of emotional labor increased burnout. Also, frequency of emotion display, variety of emotion required to be expressed and attentiveness to required display rules increased burnout. Second, Resilience had moderating effect between deep acting and burnout. Third, the moderate effect of interaction of social support from leader with surface action was found at burnout. Also, moderating effect of social support from leader were shown in frequency of emotion display with burnout and attentiveness to required display rules with burnout. Fourth, social support from colleague did not have buffering effect on emotional labor and burnout. Conclusions: It is expected that the moderator variables identified in this study can be used for prevention and treatment of burnout caused by emotional labor.

• Journal of agriculture & life science
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• v.44 no.1
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• pp.25-32
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• 2010

This study examined the effect of moisture level at ensiling on fermentation characteristics of barley and rye silage. The moisture levels, 60 (low; LM), 70(medium; MM) and 80% (high; HM), were controled by adding water or pre-wilting. Barley silage had higher pH and latate:acetate ratio in LM than the other treatments, but those of rye in MM were higher. The concentrations of lactate, total FA and acetate in HM were higher than the other treatments, but propionate concentration in LM was higher than HM. Total N concentrations of barley and rye were highest in MM and LM, respectively. The $NH_3-N$ concentration and total N:$NH_3-N$ ratio of barley were higher in HM than those in LM and MM. With increasing moisture content, buffering capacity of barley and rye silages increased, whereas decreased by increase of pH. There was a negative correlation between moisture content vs. pH of barley and rye silages. However, moisture content vs. the concentrations of total VFA and $NH_3-N$ and the ratio of total N:$NH_3-N$ had a positive correlation. Tn conclusion, the ideal moisture content of barley and rye for silage was 70-80%, but silage quality could be rapidly decreased by pre-wilting to 60% moisture content.

• Journal of dental hygiene science
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• v.22 no.1
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• pp.57-66
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• 2022

Background: This study aimed to investigate the effect of selecting commercially available blending teas and applying them to bovine teeth on color change over time. Methods: After selecting healthy bovine teeth, using a cutting-disc, 105 specimens with a dimension of 5×5×3 mm were prepared, and 15 specimens were distributed to each group. Black tea was used as a positive control, water was used as a negative control, and blended tea of five types was used as an experimental group. First, pH and buffering capacity were measured with a pH meter, and tooth color was determined using a spectrophotometer before immersion in the blending tea solution and 1, 5, 7, 14, and 21 days after immersion. Thereafter, the shape change of the enamel surface was observed using a scanning electron microscope, and SPSS ver.26 was used to analyze the color change. Results: The average pH of the five blending teas in the experimental group was 3.78, and the pH of group 3 (strawberry rhubarb) was the lowest at 3.22. The pH levels of black tea and water were 5.19 and 7.30, respectively. The buffering capacity was the highest in group 3 at both pH levels of 5.5 and 7.0. The L^*a^*b^* color change according to immersion time was the largest in group 4 (rooibos yellow flower), and the amount of color change was large in black tea and group 4. As a result of observing the enamel surface of bovine teeth, changes in the surface shape were noted in all groups immersed in the experimental solution for 21 days, except for water. Conclusion: There was a significant difference between the experimental groups in terms of color change according to the immersion time, and color and enamel surface changes were observed in black tea and all experimental groups, except for water.

• Journal of Family Resource Management and Policy Review
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• v.23 no.4
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• pp.23-39
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• 2019

This study aimed to explore the moderating effect of family strengths on the effect of work-family conflict on happiness in dual-income married couples. This study included 316 married employees who live in Seoul and have children attending junior high or lower grade schools. A survey was conducted December 1-30, 2018 by distributing questionnaires to child care centers, kindergartens, schools, companies, religious institutions, and other locations. The results are follows. First, in this study, the degree of family→work conflict was higher than that of work→family conflict in dual-income married couples, indicating that role conflict at work is greater due to family role pressures. Second, among the socio-demographic characteristics of dual-career couples, monthly income, family→work conflict (an independent variable), and family problem-solving skills (a moderating variable; a subcategory of family strengths) had a significant impact. In the analysis of the effect of work-family conflict on happiness, the higher the monthly income, the lower the family→work conflict, and the higher the family problem solving ability, the higher the feeling of happiness among dual-income married couples. When the work role conflicts from family life roles were more highly perceived in dual-income married couples. Moreover, family→work conflict and an interaction term of family problem-solving ability were identified as variables that had significant effects on happiness. Third, family problem-solving ability was identified as a moderator buffering the effect of work-family conflict on happiness.

• Journal of Family Resource Management and Policy Review
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• v.21 no.3
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• pp.121-139
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• 2017

This study aimed to explore the moderating effect of social support resources on the life satisfaction and caregiving burden of family caregivers taking care of the elderly in long-term care services. The study participants were selected from among the family caregivers utilizing 30 home care centers in Seoul, Korea. Of the candidates who agreed to participate in the study, 250 caregivers who had supported the elderly at home for at least 6 months were selected. The data collected were analyzed using SPSS ver. 21.0. The study findings were as follows. First, the whole family caregivers' caregiving burden of family caregivers was found to be slightly higher than the median value. More specifically, the physical burden was the heaviest, followed by the family relationship burden, the social activity burden, the emotional burden, and the financial burden. Social support resources and life satisfaction were found to be a little bit higher than the median value. Second, the variables that statistically significantly increased life satisfaction, starting with the strongest effect, were a lower psycho emotional burden, greater informational support resources, a lower economical burden, greater emotional support, a younger caregiver age, a higher monthly income, and a shorter care period. Third, informational support resources were found to have a moderating effect on the relationship between the support burden and life satisfaction. The more the participants used the informational support resource subcategory of the social support resources, the narrower the life satisfaction decrease, even though the caregivers felt a support burden. Informational support resources appear to have a statistically significant buffering effect.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.3169-3183
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• 2018

Based on the affective event theory, the purpose of the study is to examine the effect of the individual difference regulatory focus on the process in which the work events affect job engagement under organizational circumstances. To this end, 232 financial workers were surveyed on positive events, positive affects, regulatory focus and job engagement. The results of the analysis are as follows. First, the positive events generated positive affects and showed positive influence on job engagement. Second, the effect of positive affects on job engagement has been shown to be discriminatory depending on the level of regulatory focus. The higher the level of promotion focus, the stronger the effect on job engagement of positive affects, and the higher the level of prevention focus, the weaker the effect on job engagement of positive affects. Third, the moderated mediated effect was found to be significant only in the prevention focus. The magnitude of indirect effects on job engagement by positive events was found to be weakened when the prevention focus was high. Finally, the implications and future research issues were discussed.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1437-1444
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• 2023

This study was conducted to verify the moderating effect of happiness in the relationship between stress and generalized anxiety in adolescents. The subjects of the study were 54,948 middle and high school students who participated in the 16th Adolescent's Health Behavior Survey conducted in 2020. Data were analyzed using SPSS 24.0 and Process Macro 4.0. The results of the study showed that stress had a significant effect on generalized anxiety of adolescent. The higher the stress, the higher the level of generalized anxiety. And it was found that happiness moderated the relationship between stress and generalized anxiety. In other words, it was confirmed that happiness has the effect of buffering the negative impact of stress on generalized anxiety. Therefore, in order to alleviate generalized anxiety in adolescents, it is recommended to prepare and implement various programs that can improve happiness.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.133-138
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• 2001

In this study, an attempt was made to increase the survival rate of bifidobacteria entrapped in alginate in the gastrointestinal tract, and to investigate the potential industrial applications, for example lyophilized capsules and yogurt. First, the protective effect of various food additives on bifidobacterial survivability was determined after exposure to simulated gastric juices and bile salts. The additives used in this study were skim milk (SM), polydextrose (PD), soy fiber (SF), yeast extract (YE), chitosan (CS), $\kappa$-carageenan ($\kappa$-C) and whey, which were added at 0.6% concentration (w/v) to 3% alginate-bifidobacterial solution. In the simulated gastric juices and bile salts, the protective effect of 0.6% skim milk-3% alginate (SM-A) beads on the survival rate of bifidobacteria proved to be higher than the other additives. Second, the hydrogen ion permeation was detected through SM-A vessel without bifidobacterial cells at different SM concentrations (0.2%, 0.4%, 0.6%, 0.8%, and 1.0%). There were no differences in terms of the pH decrease in SM-A vessels at 0.6%, 0.8%, and 1.0% (w/v) SM concentrations. The survival rate of bifidobacteria in SM-A beads would appear to be related to the SM buffering capacity against hydrogen ions and its tendency to reduce the pore size of bead. In this experiment, the survival rate of bifidobacteria entrapped in beads containing 0.6% SM showed the highest viability after exposure to simulated gastric juices for 3h, thereby indicating that 0.6% SM is the optimum concentration fir 3% alginate bead preparation. Third, the effect of SM-A beads on the freeze-drying and yogurt storage for 10 days was investigated. SM-A beads were found to be more efficient for freeze drying and yogurt storage than untrapped cells and the alginate bead. Consequently, the survival rate of bifidobacteria entrapped in SM-A beads was increased in simulated gastric juices, bile salts and probiotic products, such as lyophilized capsules and yogurt, SM-A beads can be expected to produce high value probiotic products.