• Journal of Korean Academy of Nursing
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• v.41 no.5
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• pp.663-672
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• 2011

Purpose: Purpose of this study was to investigate the status of depression in academic high school students and path analysis model for exploring the mediating role of entrapment to depression in relation to academic stress and perceived social support. Methods: Measurements were four reliable questionnaires measuring academic stress, social support, entrapment, and depression. Data were collected from students in 17 high schools in Seoul. Results: Students (n=5,346) completing the questionnaires indicated depression & entrapment from academic stress. Depression was more prevalent in girls, those whose parents' household income was less than two million won, who did not live with father or mother or both due to divorce, separation, or death, and those who smoked or used alcohol. Entrapment was more prevalent in students similar to cases of depression and in seniors. According to the proposed path model, 48.6% of depression was explained by academic stress, social support, and entrapment. The indirect effect of entrapment as a mediator between academic stress and depression was verified and larger than the direct effect of academic stress on depression. Conclusion: Considering levels of depression and entrapment demonstrated by these students, better mental health programs with diverse strategies should be developed for their psychological well-being.

• Journal of Korean Academy of Nursing
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• v.42 no.4
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• pp.599-607
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• 2012

Purpose: This study was conducted to evaluate the effect of a one-session spouse-support enhancement childbirth education on childbirth selfcefficacy and perception of childbirth experience. Methods: The design of this study was a nonequivalent control group pretest-posttest experiment. The participants in the study were 31 couples in the experimental group and 30 in the control group. The experimental couples were provided with one session on spouse-support enhancement childbirth education the night before delivery. Data were collected at two hours after delivery using the Childbirth Self-Efficacy Inventory (CBSEI) and perception of childbirth experience scale. Data were analyzed using PASW statistics 18 program. Frequencies, percentage, mean, $x^2test$, t-test were used for data analysis. Results: Childbirth self-efficacy significantly increased in the experimental group as compared to the control group, but there was no significant difference in perception of childbirth experience in the experimental group compared to the control group. Conclusion: The results suggest that a one-session childbirth education has beneficial effects on enhancing childbirth self-efficacy in pregnant couples. A one-session spouse-support enhancement childbirth education is recommended as an effective nursing intervention to promote couple's childbirth self-efficacy and it is also recommended that modifications of program to promote women's childbirth experience should be considered.

• Land and Housing Review
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• v.2 no.3
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• pp.277-285
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• 2011

To reinforce bearing capacity-changed section or different foundation in the same building, empirical or simple tools have been used. To solve this problem, an analytical solution which can evaluate and reinforce the stability of foundation is introduced. To suggest a clue for the problems, current foundation reinforcing method is studied through recent literature studies and the structural analyses of foundation slab are performed on the pile foundation of 49$m^2$, 59$m^2$ and 84$m^2$ I type apartments in 15 story building. The analyses are conducted with SAP 2000, a computer program for ordinary structural analysis. To predict the moments of slab by ground non-uniformity, the structural analysis results for the foundation slab of 3 types 15 story apartment buildings in 49$m^2$, 59$m^2$ and 84$m^2$ I type on non-uniformity ground are shown in the diagrams.

• Informatization Policy
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• v.23 no.2
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• pp.35-53
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• 2016

This paper attempts to present critical issues of the information society and an alternative research addressing the challenges of ensuring that ICT is applied in ways that are enabling and responsive to social contexts in which people live their lives. Drawing the question of why insights arising from the mainstream vision are rarely useful in policies, the study highlights some developmental paradigms linked to ICT. It explores how ICT is seen as a means to development, and elaborates on the limitations of how current issues are related to the quality of life. The results indicate that ICT reduces quality of life while economic growth entails the opposite. The research framework here involves some meaningful components of cultural residues: independence, risk-taking, government responsibility by mapping how the level of ICT is distributed in the topology of values around the world. Moving to the next phase, ICT policy design and implementation need to be set up practically in a broad perspective that can be pursued by those concerned with social and technological innovation.

• Polymer(Korea)
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• v.26 no.2
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• pp.179-184
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• 2002

Polymer electrolyte films consisting of poly (vinylidenefluoride-hexafluoro-propylene) (PVdF-HFP) $H_3PO_4$and a mixture of ethylene carbonate(EC), $\gamma$-butyrolactone(BL) and dimethylcarbonate (DMC) were examined in order to obtain the best compromise between high protonic conductivity, homogeniety and dimensional stability. Measurements of differential scanning calorimetry and ionic conductivity have been carried out for various compositions. The highest proton conductivity of 7.3 $\times$$10^{-3}Sm^{-1}$ at $30^{\circ}C$ were obtained for a film of 30(PVdF-HFP) + 50EC/DMC + 20H$_3$PO$_4$. From the thermal study, it has been found that the PVdF-HFP gels are stable up to $80^{\circ}C$, and the $H_3PO_4$ enhances the miscibility of the polymer and the solvent by interacting sensitively with polymer segments.

• Membrane Journal
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• v.8 no.1
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• pp.29-41
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• 1998

Thin-film composite reverse osmosis membranes of aromatic polyamides were prepared by the interfacial polymerization. Aromatic polyamides as active skin layer were made from the interfacial polymerization of MPD(m-phenylene diamine) in the aqueous and TMC(trimesoyl chloride) in HCFC(1,1-dichloro-1-fluoroethane) organic solvent. The performances of the various reverse osmosis composite membranes prepared by changing processing variables were examined. The performance of membrane manufactured by batch system was varied with organic solvent, monomer concentration, dipping time, heat treatment temperature, acid acceptor, ethanol post treatment, and acid post treatment. Ethanol post treatment was the most dominant factors in increasing permeate amount, while the monomer concentration and dipping time were the main factors in increasing selectivity. The spiral-wound module was produced with the membrane prepared at optimum condition of the continuous process. Comparing the performance of this membrane module made here with that of commercial membrane module, the permeate flux was increased by 33% while the rejection was decreased by 5%.

• Membrane Journal
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• v.27 no.5
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• pp.441-448
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• 2017

In this study, the effects of membrane characteristics on the power generation performance in reverse electrodialysis (RED) have been investigated with pore-filled ion-exchange membranes (PFIEMs) prepared by employing a porous polyethylene substrate and the mixtures of three cross-linking agents. As a result, it was confirmed through the correlation analyses that the cross-linking degree and free volume of the PFIEMs were effectively controlled by mixing the cross-linking agents having different molecular sizes, influencing complexly the electrochemical characteristics of the membranes and the power generation performance in RED. In particular, the pore-filled cation-exchange membranes at the optimum cross-linking conditions exhibited the power generation performance superior to that of the commercial membranes and the pore-filled anion-exchange membranes also showed the excellent performance close to that of the commercial membrane.

• Membrane Journal
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• v.28 no.4
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• pp.279-285
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• 2018

The pervaporation separation of isopropanol/water mixture was carried out on a series of chemically cross-linked poly(vinyl alcohol)(PVA) composite membranes. The membranes were prepared by casting three kinds of PVA solutions with varying concentrations of PVA and GA onto polyacrylonitrile (PAN) support followed by thermal cross linking. As the PVA concentration increased, the flux decreased but separation factor was increased. It was confirmed that the composite membrane coated with PVA-3 (98~99% hydrolyzed) at a concentration of 7 wt% PVA and 20 wt% glutaraldehyde (GA) exhibited a flux of $209g/m^2h$ and a separation factor of more than 100. The submerged module test was carried out with controlled feed tank temperature and IPA concentration of the feed solution. The continuous concentration of IPA solution was increased from 90% to 99% after 60 h.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.417-423
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• 2006

A series of amine functionalized MCM-41 catalysts were prepared by aminopropyltrimethoxysilane grafting and their catalytic performance in Knoevenagel reaction of selected substrates was investigated. Water resistant and catalytically active amine grafted MCM-41 was prepared by post-synthetic silylation using methyltrimethoxysilane ; hydrogen bonding of the water molecules formed during the condensation reaction to the active N group was suppressed, which led to high TON of the reaction. Amine functionalized MCM-41 prepared by coating method produced high conversion, but the TON of the catalyst was much lower than that of the amine grafted MCM-41; pore volume of the functionalized MCM-41 decreased substantially and large portion of the immobilized amine is believed to be hydrogen bonded to each other, which can result in decrease in the basicity of the N group. A secondary amine group was prepared by room temperature condensation between aminopropylsilane and chloropropylsilane, and the MCM-41 grafted with the secondary amine group demonstrated the highest catalytic activity among the catalysts prepared.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.393-398
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• 2006

There have been a lot of works in order to develop an excellent adsorbent for separation of olefin and paraffin. In the present work, the adsorption characteristics of mesoporous MCM-41 containing silver ion for 1-butene and n-butane were studied. The adsorption ability for the 1-butene depending on thermal treatment were also investigated.MCM-41 exhibits much higher adsorption amounts for 1-butene as well as n-butane, compared to those of Ag/13X zeolite. In case of MCM-41 containing silver ion, the adsorption amount of 1-butene dramatically increased due to the ${\pi}$-complexation, whereas the adsorption amount of n-butane decrease. The Ag/MCM-41 after the thermal treatment at 373 K under evacuation exhibit the highest 1-butene/n-butane adsorption ratio, expecially at low pressure (100 Torr).