• Polymer(Korea)
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• v.25 no.4
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• pp.476-485
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• 2001

In this study, we tried to design and synthesize using natural polymers (hyaluronic acid and sodium alginate) and also to make some kinds of scaffolds as sponge type for reducing the burst effect of loaded drug from them. Photo-dimerizable group was incorporated to hyaluronic acid and degradable hydrogel was prepared by the UV radiation of the polymer. The pore size and its distribution of scaffold were controlled by changing microsphere production conditions such as solution concentration and spraying pressure. It was found that drug release behavior from synthesized scaffolds was affected by hybridization of two naturally originated polymers (cinnamoylated tetrabutylammonium hyaluronate: CHT and cinnamolylated sodium alginate: CSA) and the obtained scaffolds were degraded in fairly long time (about 2 months) under in vitro environment. Therefore, we expect that obtained scaffolds can be applicable for the tissue regeneration scaffolds in the fields of orthopaedic surgery.

• Nuclear Engineering and Technology
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• v.22 no.4
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• pp.326-336
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• 1990

Recent experiments show the existence of spacer grid improves the heat removal from the fuel rods during the reflood phase of LOCA. The local heat transfer within and downstream of the grid is increased due to the earlier quenching than rod surface, shattering of the entrained droplets into smaller ones which can be more easily evaporated and enhanced turbulent effect. Therefore, the consideration of these phenomena is necessary for the DFFB regime which prevails above the water level during the reflood. In this paper, droplet breakup model at spacer grid has been developed and incorporated into RELAP5/MOD2. Verification calculations are carried out for FEBA tests which examine the thermalhydraulic performance of grid spacer during reflood.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.365-373
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• 2017

The purpose of this study was to examine relationships among positive psychological capital and social support on depression and identify the factors that influence on depression in the adolescents. The data were collected from 140 adolescents in the two middle school located J city using self-reported questionnaires and May 9 2017 to May 19 2017. The data were analyzed by descriptive statistics, T-test, ANOVA, Pearson's correlation coefficient, and stepwise multiple regression with SPSS 20.0 program. Depression was found to be in a significant negative correlation with positive psychological capital and social support. The result of the stepwise multiple regression indicates the positive psychological capital, social support and economic status predict 22.4% (F=14.38, p<.001) of depression. Therefore, it is necessary to develop convergence positive psychological capital and social support strategy program for decrease and prevents depression in adolescents.

• Membrane Journal
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• v.14 no.1
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• pp.57-65
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• 2004

The effect of porous support layer resistance and PDMS (polydimethylsiloxane) coating thickness on ethylene/nitrogen separation of composite membranes was studied with the model of Pinnau and Wijmans〔1〕. To control the support resistance (or permeance), PES porous membranes were prepared by phase inversion process with various PES/NMP dope concentrations. The thickness of selective PDMS top layer was controlled by using a spin coater. Its cross-section and coating thickness were observed by scanning electron microscope (SEM). Pure gas permeation test was done with ethylene and nitrogen, respectively. The experimental result for olefin/nitrogen separation process matched well with theoretical result from the model used. The result shows that optimization between PDMS coating thickness and support resistance is important to get PDMS composite membranes with best performance.

• Polymer(Korea)
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• v.37 no.5
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• pp.649-655
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• 2013

In order to use as supporters for the reinforced composite fuel cell membrane, poly(acrylic acid)-grafted porous polytetrafluoroethylenes (PTFEs) were prepared via introduction of poly(acrylic acid) graft chains by a radiation grafting method. FTIR was utilized to confirm the successful introduction of poly(acrylic acid) graft polymer chains into the porous PTFEs. Contact angles were examined to observe the hydrophilicity of the surface of the prepared substrates. The result indicates that the hyrophilicity of the surface in the prepared substrates increases with an increase in the number of hydrophilic polymer chains. FE-SEM, gurley number, and tensile strength were also utilized to characterize the prepared substrates.

• Journal of Digital Convergence
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• v.13 no.9
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• pp.387-395
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• 2015

The aim of this study was to investigate effects of socio-demographic, household, social support, health-related factors on adolescent internet use time. Multiple regression analysis was conducted to examine factors affecting adolescent internet using time, and this study used the 2014 10th Korean Youth Health Risk Behavior On-line Survey data by Centers for Disease and Prevention. Results show that as for socio-demographic factors, being male, lower economic status, being middle school student, and having poor academic grade were; as for household factors, youth-led, one-parent, grandparent(s), multicultural, and North Korean defectors family were; as for social support factors, the absence of family support, the absence of friend support and the absence teacher support were; and as for health-related factors, less exercise, higher level of stress, and lower level of subjective happiness were associated with increased internet using time. Based on these results, convergent implications about effective intervention strategies that adolescents can use internet appropriately were discussed in the section of conclusion.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.479-491
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• 2018

This study aims to figure out factors influencing health and moderating effect of social support resource between those factors and health of low income women in diverse spheres. The data of low income women were 239 cases and were utilized SPSS ver. 21 program. The main results of this study are as follows: firstly, health of low income women is identified medium level. Secondly, education level, self-efficacy and social support resource are related to the self-rated health of low income women. Especially, social support resource functions as moderators on between education and self-rated level of the health of low income women. Consequently, the findings suggest the need to expand the social intervention range to promote health of low income women from cost benefit to psychological support such as capacity building for self-management and establishment of safety-net to extend social support. And subsequently, the time attribute of the factors related to low-income women's health and the diverse characteristics of the subjects should be considered.

• Korea journal of population studies
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• v.30 no.2
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• pp.23-44
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• 2007

The primary aim of this study is to examine difference in psychological well-being (PWB) and family support and explore its factors by the types of productive activity: paid labor, voluntary activity, or caregiving for their grandchildren. Three hundred females aged over 60 currently participating in productive activities were interviewed. The main results are as follow. First, PWB of volunteers is higher than any other group. Second, level of support provided by family members is highest for the group of grandchildren caregiving. Third, the variables affecting PWB for paid workers are educational level and material reward. As for the volunteers, PWB is explained by satisfaction with the given activity and instrumental support of their family members on it. PWB of grandchildren caregivers is explained by their marital status, income, material reward, emotional and instrumental support.

• Journal of Digital Convergence
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• v.19 no.8
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• pp.133-139
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• 2021

This research emphasized that the importance of Social Support and verify the effects of Social Support on Subjective Well-Being through Achievement Motivation. In addition, the mediating role of Achievement Motivation was clearly identified as a key variable that can lead to Subjective Well-Being. To achieve this purpose of research, an empirical analysis was conducted on Chinese students attending domestic universities. Through empirical analysis, it was found that Social Support improve Motivated Success and Motivated Avoid Failure. Furthermore, Motivated Success and Motivated Avoid Failure were found to increase the level of Subjective Well-Being. Furthermore, in the relationship between social support and subjective well-being, verification of individual mediating effects and multi-parameter effects of Motivated Success and Motivated Avoid Failure showed that only the motivation for success has a partial mediating effect. Finally, practical implications from this study were presented and future research directions were discussed.

• Journal of the Health Care and Life Science
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• v.9 no.1
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• pp.153-160
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• 2021

This study is to investigate the effect of early childhood teachers' resilience and social support on job stress. The degree of resilience, social support, and job stress was measured for 250 teachers of early childhood education institutions located in City I, and the relationship and relative influence were analyzed. For data processing, correlation analysis and multiple regression analysis were performed using the SPSS 18.0 program. As a result, first, early childhood teachers' resilience and social support were measured at a slightly higher level than average, and job stress at a slightly lower level. Second, the resilience and social support of early childhood teachers had a positive relationship, and the resilience and social support had a negative correlation with job stress. Third, as a result of analyzing the relative influence of early childhood teachers' resilience and social support on job stress, 83% explained that organizational environmental factors, material support, and behavioral factors affect job stress. These results suggest that it is most important to provide resilience and social support that can affect the reduction of job stress of in-service teachers.