• Smart Structures and Systems
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• v.26 no.1
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• pp.89-102
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• 2020

Shape memory alloy (SMA)-based Superelasticity-assisted Slider (SSS) is proposed as an engineering solution to practically exploit the well-accepted advantages of both sliding isolation and SMA-based recentering. Self-centering capability in SSS is provided by austenitic SMA cables (or wire ropes), recently attracting a lot of interest and attention in earthquake engineering and seismic isolation. The cables are arranged in various novel and conventional configurations to make SSS versatile for aseismic design and retrofit of structures. All the configurations are detailed with thorough technical drawings. It is shown that SSS is applicable without the need for Isolation Units (IUs). IUs, at the same time, are devised for industrialized applications. The proof-of-concept study is carried out through the examination of mechanical behavior in all the alternative configurations. Force-displacement relations are determined. Isolation capabilities are predicted based on the decreases in seismic demands, estimated by the increases in effective periods and equivalent damping ratios. Restoring forces normalized relative to resisting forces are assessed as the criteria for self-centering capabilities. Lengths of SMA cables required in each configuration are calculated to assess the cost and practicality. Practical implementation is realized by setting up a small-scale IU. The effectiveness of SSS under seismic actions is evaluated using an innovative computer model and compared to those of well-known Isolation Systems (ISs) protecting a reference building. Comparisons show that SSS seems to be an effective IS and suitable for earthquake protection of both structural and non-structural elements. Further research aimed at additional validation of the system are outlined.

• Journal of Korean Society of Steel Construction
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• v.28 no.4
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• pp.223-229
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• 2016

This study proposes a new technology for a smart damper with flag-shaped behavior using the combination of magnetic friction and rubber springs. The magnet provides friction and, thus, energy dissipation, and the rubber springs with precompression contribute to present self-centering capacity of the damper. To verify their performance, this study conducts dynamic tests of magnet frictional dampers and precompressed rubber springs. For the purpose, hexahedron Neodymium (NdFeB) magnets and polyurethane rubber cylinders are used. In the dynamic tests, loading frequency varies from 0.1 to 2.0 Hz. The magnets provide almost perfect rectangular behavior in force-deformation curve. The rubber springs are tested without or with precompression. The rubber springs show larger rigid force with increasing precompression. Lastly, this study discusses combination of rigid-elastic behavior and friction to generate 'flag-shaped' behavior for a smart damper and suggests how to combine the magnets and the rubber springs to obtain the flag-shaped behavior.

• Journal of the Korea Concrete Institute
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• v.18 no.4 s.94
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• pp.497-506
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• 2006

The precast concrete beam-column connectors for the high-rise office buildings were investigated experimentally in this study. The specimens of general precast beam-column connector which is used in a domestic site, specimen of DDC(dywidag ductile connectors) of Germany, and specimen of DDC with post-tensioning and modified DDC with post-tensioning were constructed and tested to verify the safety. The DDC with and without post-tensioning showed reliable joint strength and ductility but failed in critical inclined shear crackings at the column. The modified one showed better behaviors in tests because they did not show critical column crackings at failure. The use of prestressing did not helpful significantly to increase the strength and ductility of connectors but helpful only to develop self-centering behavior for stability.

• Journal of Agricultural Extension & Community Development
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• v.17 no.4
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• pp.957-984
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• 2010

The aim of this research is to delineate how daily living activities, depression, self-respect, and social activity participation affects the life satisfaction of the rural elderly. The subjects of the research were elderly over-65-year-olds living in Yeoju, Gyeonggido and conducted from November 15 to November 30, 2009. The sampling method was convenience sampling among non-probability sampling, a total of 339 were used as analysis data. The collected data were then put through-frequency analysis, correlation analysis, simple regression analysis, analysis of variance, Kruskal-Wallis, and feasibility verification through SPSS SAS 9.1.3 program. As a result of hypothesis verification, daily living activities have a positive influence over life satisfaction. And the higher the elderly's self-respect, the greater their life satisfaction, and it was verified that depending on social activity participation, there is a difference in their life satisfaction. The purpose of this study is to verify and carry out action plan and ital.

• Korean Journal of Child Studies
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• v.29 no.1
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• pp.207-225
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• 2008

This study used content analysis to explore how experience and coping style affect burnout in child-counselors. Data were self-reports collected by interviews of with 30 child counselors. The contents of the interviews showedthe cause of, psychological and physical responses to, and the ways the subjects coped with burnout. The summarized results are that (1) they experience burnoutwhen they feel incompetent, when counseling is ineffective, when they are under-compensated and when they are poorly supervised, (2) The psychological and physical responses to burnout are diminished self-esteem, depression, incompetence, chilling effect on other fields, and digestive problems. (3) Child-counselorscope with burnout mostly by centering on the problems and by searching for social support.

• Journal of Korean Home Economics Education Association
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• v.14 no.2
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• pp.79-95
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• 2002

The Purposes of this study are first to develop the teaching and learning plan for the dress part in high school's Home Economics by the application of the values clarification theory then to apply it to the classroom activities. and lastly to analyze its effects. We developed the master plan for teaching and learning, and developed the 12 hour sub plans including 7 activities and learning materials. The effects of the teaching are as followings: First, When the self-esteem was compared with the whole classes, there was no difference between the twos, but a boy and a girl who were observed as not making a value-oriented life marked higher score in answering the self-esteem. Second. It was found that values clarification theory made student's degree of participation and interest higher and helped them to choose their dresses in the real life.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.106-112
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• 2006

Tissue hyperplasia is one of the most frequently encountered complications when self-expanding metallic stents are placed in benign non-vascular luminal organ strictures, thus causing restenosis of the lumen. The investigators postulated that ionizing irradiation could be applied to prevent restenosis caused by tissue hyperplasia in non-vascular luminal organs as it reduced coronary or peripheral arterial narrowing successfully. The authors combined $\beta$-irradiation using $^{188}Re-MAG_3$ solution with balloon dilation for animal and clinical studies because this new treatment approach had the advantages such as low penetration depth of $\beta$-ray, self-centering irradiation, and mechanical effect of balloon dilation over using $\gamma$-irradiation with afterloading devices in this article, the concept and mechanism of radioisotope balloon dilation, and animal and clinical studies using radioisotope balloon dilation are reviewed.

• The Journal of Information Systems
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• v.15 no.3
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• pp.233-252
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• 2006

Recently, negative sides of internet, internet and/or game addiction and unethical behavior over internet, have been largely publicized in our society. There have been numerous studies to explore the problems and solutions, but these lack considering broader set of research variables. Therefore, this research investigated how i) internet users' self characteristics and ii) cognitive characteristics toward internet influence iii) internet addiction and iv) information ethics respectively. Especially, this study focused on college students, more mature beings than elementary, middle and high school students with whom most other researches have dealt so far. Major findings of this study are as follows: (1) Willingness to develop relationships over internet, usefulness of internet use, a degree to perceive the cyber space as real, and a degree to express self over internet have significant effects on disabled life style. Self respect willingness to develop relationships over internet, usefulness of internet use, a degree to perceive the cyber space as real, and capability of using internet have significant effects on the lack of control over internet. Willingness to develop relationships over internet, self control, and a degree to express self over internet have significant effects on the lack of control over internet. 2) Regarding the effects of independent variables(self characteristics and cognitive characteristics) on information ethics through internet addiction factors, self respect self control, a degree to perceive the cyber space as real, and capability of using internet have directly and indirectly significant effects on information ethics through internet addiction. Then we suggested four approaches to reduce the internet addiction and improve the information ethics based on the findings.

• Journal of the Korean Home Economics Association
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• v.41 no.8
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• pp.79-95
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• 2003

The main goal of this program is to build a healthy adolescent culture tv broadening the understanding of adolescents and recognition of the environment as well through the development of educational programs centering on the domains of peer relationships, intimacy in dating relationships and sex, leisure activities, and consumption life of adolescents. The program was carried out to 10 young boys and girls for two days/one night and the major findings of the effects of the program through a qualitative evaluation were as follows: First, the program provided adolescent with a proper opportunity to promote a sense of self-confidence through the self-reevaluation process. Secondly, the program provided adolescents with a chance to firmly recognize to become good friends with others though the enhancement of self-esteem, which helped them to build a healthy peer relationship. Thirdly, adolescents were able to promote their views on sex and sexual decision-making by acquiring a proper knowledge of intimacy in dating relationships and of sex, and by candidly expressing their own opinions on sex with instructors. Fourthly, the program provided adolescents with an opportunity to look back on their leisure life with family members which had been neglected thus far and to renew their recognition of active leisure activities. Fifthly, the program provided adolescents with a chance to reflect on their unplanned consumption life and to be firmly determined to refrain from impulsive purchasing and extravagance.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1147-1157
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• 2009

Recently this country has carried out the coast reclamation centering on the west and south coast for effective practical use of a country, considering purchase of materials and environmental problem, and carrying into effort the reclamation method after dredging the ground in the ocean. In this large scale ocean dredging reclaiming work, prediction the ground subsidence after reclaiming is very important for not only expense lose by overestimation or underestimation but also hereafter the best suited project establishment. this study carries out sedimentation and self weight consolidation in each cases and searches the features to analyze effect on kinds of soil of ground before dredging, abandonment height when it abandons momentary, void ratio, difference of abandonment height when it abandons by stages and difference of particle content of spoil.