• 국제초고층학회논문집
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• 제6권1호
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• pp.83-89
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• 2017

Due to the time-dependent properties of materials, structures, and loads, accurate time-dependent effects analysis and precise construction controls are very significant for rational analysis and design and saving project cost. Elevation control is an important part of the time-dependent construction control in supertall structures. Since supertall structures have numerous floors, heavy loads, long construction times, demanding processes, and are typically located in the soft coastal soil areas, both the time-dependent features of superstructure and settlement are very obvious. By using the time-dependent coupling effect analysis method, this paper compares Shanghai Tower's vertical deformation calculation and elevation control scheme, considering foundation differential settlement. The results show that the foundation differential settlement cannot be ignored in vertical deformation calculations and elevation control for supertall structures. The impact of foundation differential settlement for elevation compensation and pre-adjustment length can be divided into direct and indirect effects. Meanwhile, in the engineering practice of elevation control for supertall structures, it is recommended to adopt the multi-level elevation control method with relative elevation control and design elevation control, without considering the overall settlement in the construction process.

• 한국지역사회생활과학회지
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• 제26권2호
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• pp.275-286
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• 2015

This study investigates the effects of elementary school students' parental attachment and self-control on their peer relationships and the mediating effect of their self-control ability on the relationship between their parental attachment and peer relationships. A total of 490 fifth- and sixth-graders in Andong City were surveyed. Data were collected using a questionnaire for their parental attachment, self-control ability, and peer relationships and analyzed using the t-test, Pearson's correlation analysis, the hierarchical regression analysis, and the Sobel test. The results indicate significant differences in parental attachment, self-control ability, and peer relationships according to gender. Parental attachment was significantly correlated with emotional control ability and behavioral control ability, and there were significant correlations between parental attachment and peer relationships and between self-control ability and peer relationships. Parental attachment had a significant direct effect on peer relationships, and self-control ability mediated the relationship between parental attachment and peer relationships.

• 한국정보시스템학회:학술대회논문집
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• 한국정보시스템학회 1996년도 추계학술발표회 발표논문집
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• pp.29-48
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• 1996

Previous studies on user training have largely focused on assessing models which describe the determinants of information technology usage or examined the effects of training on user satisfaction, productivity, performance, and so on. Scant research efforts have been made, however, to examine those effects of training by using theoretical models. This study presented a conceptual model to predict intention to use information technology and conducted an experiment to understand how training for computer skill acquisition affects primary variables of the model. The data were obtained from 32 student subjects of an experimental group and 31 students of a control group, and the information technology employed for this study was a university's electronic mail system. The study results revealed that attitude toward usage and perceived behavioral control helped to predict user intentions; outcome expectations were positively related to attitude toward usage; and self - efficacy and perceived behavioral control. The changes in those variables suggest more causal effects of user training than other survey studies.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1296-1304
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• 2013

This study performed an analysis on power demand reduction effects exhibited by demand response programs, which are advanced from traditional demand-side management programs, in the smart grid environment. The target demand response systems for the analysis included incentive-based load control systems (2 month-ahead demand control system, 1~5 days ahead demand control system, and demand bidding system), which are currently implemented in Korea, and price-based demand response systems (mainly critical peak pricing system or real-time pricing system, currently not implemented, but representative demand response systems). Firstly, the status of the above systems at home and abroad was briefly examined. Next, energy saving effects and peak demand reduction effects of implementing the critical peak or real-time pricing systems, which are price-based demand response systems, and the existing incentive-based load control systems were estimated.

• 한국환경교육학회지:환경교육
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• 제10권2호
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• pp.213-228
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• 1997

This study was planned to test the educational effects of self-guiding environmental interpretation panel. For purpose of the study, self-guiding interpretation panel was set up along the trail of green shower area of Kwang-Reung Arboretum in 1995,and the environmental behavior related variables such as attitude, locus of control, personal responsibility, general knowledge, and intention to act were closen based on Hines and his colleagues' Responsible Environmental Behavior model(1987). The pre-test/post-test non-random control group design was introduced fo test the effects of panel. ANCOVA was used to test the differences between experimental and control group because of the need to consider the effects of other variable such as socio-economic variables on the changes of environmental behavior related variables. Among 5 environmental behavior related variables, the changes of attitude and knowledge were significantly different between experimental group and control group, and the experimental group's direction of change was more favorable for environment. It is concluded that the educational effects of self-guiding interpretation panel were partially accepted. Several recommendations and restrictions of the study are presented.

• 한국생활과학회지
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• 제15권2호
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• pp.353-362
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• 2006

The purpose of this study is to develop a group counseling program for career exploration and to explore its effects on college students' self-efficacy. Main program activities consisted of 8-week sessions. Equivalent control group pretest-posttest design was employed for this study. 40 college students voluntarily participated in a group counseling of career exploration. Another 40 students were selected for a control group of this study design. The self-efficacy (23 items) was administered to both the experimental and the control groups before and after the 8-week treatments. The results of this research showed that the differences (program effects) of the experimental group in the scale were higher than those of the control group. In conclusion, a group counseling program for the career exploration had significant effects on the career exploration and self-efficacy of college students.

• Journal of Power Electronics
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• 제12권3호
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• pp.399-409
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• 2012

In DC-DC Buck converters with average current mode control, the current loop compensator provides additional design freedom to enhance the converter current loop performance. On the other hand, the current loop circuit elements append substantial amount of complexity to not only the inner current loop but also the outer voltage loop, which makes it demanding to quantify circuit and operating parameter effects on the small-signal dynamics of such converters. Despite the difficulty, it is shown in this paper that parameter effects can be analyzed satisfactorily by using an existing small-signal model in conjunction with a newly proposed simplified alternative. As a result of the study, new insight into average current mode control is uncovered and discussed quantitatively. Measurable experimental results on a prototype averaged-current-mode-controlled Buck converter are provided to facilitate the analytical study with good correlation.

• Animal Bioscience
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• 제36권6호
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• pp.920-928
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• 2023

Objective: Angora rabbits fed a low-protein diet exhibit decreased hair production performance. This study was set out to evaluate the effects of methionine on hair properties and nitrogen metabolism in Angora rabbits fed a low-protein diet and to investigate the gene expression related to hair follicle development to determine the possible molecular mechanism of methionine effects on hair follicle development. Methods: An experiment was conducted to investigate the effects of DL-methionine addition on a low-protein diet on hair development in Angora rabbits. Angora rabbits were divided into 5 groups: fed a normal diet (control), fed a low-protein diet (LP), or fed an LP supplemented with 0.2%, 0.4%, or 0.6% DL-methionine (Met). Results: The results showed that rabbits in the LP group had lower wool yield than the control rabbits, but the addition of 0.4% to 0.6% Met to LP attenuated these effects (p<0.05). Dietary addition of 0.4% to 0.6% Met to LP increased the apparent nitrogen digestibility, nitrogen utilization rate, and feed efficiency (p<0.05). Feeding LP decreased the insulin-like growth factor 1 (IGF1), keratin-associated protein (KAP) 3.1, and KAP 6.1 mRNA levels compared with the control, but the addition of 0.4% Met in LP attenuated these effects (p<0.05). Relative to the LP or control group, dietary addition of 0.4% Met increased versican mRNA levels. Conclusion: In conclusion, the addition of Met to LP could improves wool production performance and feed efficiency and reduce nitrogen emissions in Angora rabbits. Met can promote hair follicle development, which may be associated with IGF1, KAP, and the versican signaling.

• Child Health Nursing Research
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• 제26권3호
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• pp.357-365
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• 2020

Purpose: The aim of this study was to investigate internet addiction among middle school students and to examine the mediating effects of social support in the relationships of self-efficacy and self-control with internet addiction. Methods: The participants in the study were 119 middle school students in J city. The measurements included a self-efficacy scale, a self-control scale, a social support scale, and the Internet Addiction Scale for Youth. Data were analyzed using the independent t-test or Mann-Whitney U test, one-way analysis of variance, the Scheffé test, Pearson correlation coefficients, and multiple-regression using SPSS version 22.0. Mediation effects were analyzed by the Sobel test and Baron and Kenny's hierarchical analysis technique. Results: Significant correlations were found among self-efficacy, self-control, and internet addiction. Social support had partial mediating effects in the relationship between self-efficacy and internet addiction, as well as in the relationship between self-control and internet addition. Conclusion: In order to prevent internet addiction, the promotion of interactions among peers, which is a component of social support, is particularly important. It is also necessary to promote face-to-face activities that can strengthen relationships. The findings suggest that intensifying social support may help reduce the level of internet addiction in middle school students.

• 가정과삶의질연구
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• 제26권4호
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• pp.119-133
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• 2008

The purpose of this study is to investigate the mediating effects of obesity perception in the relationship between the mother's psychological control and the child's obesity stress. Questionnaires regarding the mother's psychological control, obesity perception and the child's obesity stress were administered to 1200 4th and 6th grade elementary school students in the province of Seoul, South Korea. Finally 1006 questionnaires were collected and statistically analyzed through Cronbach's, t-test, multiple linear regression analysis and stepwise regression. The main results of the study were as follows: 1) There were difference between the effects of the mother's psychological control, obesity perception, and child's obesity stress in terms of the sex, grade and obesity level of the child. 2) The mother's psychological control, obesity perception, and obesity level had an effect on the child's obesity stress. 3) As the result of searching for the mediating effects of obesity perception in the relationship between the mother's psychological control and the child's obesity stress.