• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.825-832
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• 2009

A series of laboratory experiments has been performed to investigate the flow characteristics of 2-dimensional density currents induced by selective withdrawal, which is commonly suggested as a measure for removal of high turbid water from reservoirs. Saltwater has been used to simulate the density stratification over depth and PIV(Particel Image Velocimetry) for observing the velocity structure. Experimental conditions have been established according to Richardson number, which is the dimensionless number that expresses the ratio of potential to kinetic energy. From the experiments, the patterns of longitudinal decay of centerline axial velocity induced by the withdrawal have been distinguished from other experimental cases. The rate of longitudinal decay increase as the Richardson number increases. The variations of volumetric and momentum flux along the longitudinal axis have also shown to be dependent on Richardson number.

• Journal of the Korean Home Economics Association
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• v.43 no.4 s.206
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• pp.187-201
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• 2005

This study investigated the relations of personal variables and environmental variables to the peer bullying experienced by fifth- and sixth-grade children. One result was a significant sex difference in the buoying but not in the victimization. The victimization of boys was influenced by withdrawal and assertiveness. Aggression, emotional regulation and withdrawal were important predictors for buoying, whereas withdrawal and aggression were important predictors for victimization among girls. The interactive effect of withdrawal and teacher's support on victimization was statistically significant only for boys, whereas the interactive effect of aggression, maternal affection and teacher's support on bullying was statistically significant only for girls.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.2
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• pp.95-104
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• 2018

The purpose of this study is to investigate the impact of narcissism on employees' social media addiction and how it influences their job satisfaction and organizational commitment. And this study explores if perceived organizational support can moderate the relationship between narcissism and social media addiction. For this, this study collected data from 285 employees in Korean companies through a survey method and uses SPSS 18.0 for hierarchical regression analysis in the hypothesis test. First, organizational politics increases mood modification, withdrawal and tolerance among the sub-factors of social media addiction. Second, each phenomena of social media service addiction such as salience, withdrawal and tolerance decrease each relevant factors of job satisfaction and organizational commitment. Third, withdrawal and tolerance among the sub-factors of social media addiction play the mediating roles between narcissism and each relevant factors of job satisfaction/organizational commitment. Finally, perceived organizational support decrease the effect of narcissism on mood modification, withdrawal and tolerance among the sub-factors of social media addiction. This study provides some of managerial implications to corporate executives who try to manage organizational attitudes.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.247-266
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• 2005

Subjects of this study were 621 children selected from 5th and 6th grades of elementary schools in Pusan. Factors associated with parents and peers varied by type of peer maladjustment(aggressive type and withdrawn type, compared with a control group). Particularly, the level of factors associated with peers varied from the control group by peer maladjusted types(aggressive types and, withdrawn types). Causal relationships of parents' rejection, victimization, negative representation by parents and by peers on child？s maladjustment varied by behavior types. Negative representation of peers had a direct effect only on withdrawal. On the other hand, negative representation of peers had no effect on aggression. Victimization had a first total effect on both withdrawal and aggression.

• Proceedings of the IEEK Conference
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• 2001.06a
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• pp.241-244
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• 2001

The design and fabrication of the surface acoustic wave(SAW) bandpass filters using slanted finger interdigital electrode transducers(IDTs) is investigated. The slanted finger IDTs are used to design SAW filters with good shape factor, a flat passband, and good out-of-band rejection characteristic. The slanted finger IDTS filter was simulated of three kind of IDTs structure. uniform-uniform IDT, uniform-withdrawal weighting IDTS, withdrawal weighting-withdrawal weighting IDTS. Uniform-withdrawal weighting IDTs structure SAW filters was designed and fabricated on 112$^{\circ}$ LiTaO$_3$, 128$^{\circ}$LiNbO$_3$ substrates. Designed SAW filter has about a 30% fractional bandwidth and a 70MHz center frequency.

• Korean Journal of Child Studies
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• v.30 no.3
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• pp.85-98
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• 2009

The purpose of this study was to examine the path model of child's sex, temperament, maternal parenting behavior, and child's emotion regulation on child social behaviors. The subjects were 286 elementary school children. Data were gathered through questionnaires reported by mothers and teachers. Path analysis revealed that (1) mother's overprotective or coercive parenting behaviors effected neither child's emotion regulation nor social behaviors (2) child's sex and activity level effected child's aggression both directly and indirectly through child's emotion regulation (3) child's 'activity level' and 'avoidance' temperament effected child's social withdrawal both directly and indirectly through child' emotion regulation. Findings underscore the role of emotion regulation as a mediator in predicting child aggression and social withdrawal.

• Journal of the Korean Home Economics Association
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• v.48 no.7
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• pp.15-22
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• 2010

The purpose of the present study was to examine whether relational aggression was distinct from physical aggression in young children. Moreover, the association between emotional regulation, verbal ability, maternal love withdrawal and relational aggression were investigated. Participants were 3 year old 356 children recruited from middle income families. Children's verbal ability was assessed by interview and teachers' measurement of emotional regulation and relational aggression. The results presented that confirmatory factor analysis confirmed a 2-factor model. Emotional regulation, verbal ability, and maternal love withdrawal were significant predictors of relational aggression.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.3979-3989
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• 2021

Several parametric effects on the magnetic collection have been evaluated considering dimension, strength of external magnetic field, injected velocity and particle concentration in the working fluid. Besides, accidental environments, expected in the containment of nuclear power plants, have also been addressed for the capture efficiency. The capture efficiency is especially enhanced with magnetic particle size and magnetic field strength through increased magnetic force; the non-magnetic coating thickness and fluid velocity hinder the magnetic collection. Based on the assessment, the magnetic withdrawal system can effectively capture magnetic particles even under accidental environments. Withdrawal of multifunctional magnetic particles or filtering of magnetic impurities can be effectively realized through the system.

• Journal of the Korea Society of Computer and Information
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• v.23 no.11
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• pp.203-209
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• 2018

The purpose of this study was social withdrawal, depression, and self - esteem affect adolescents' mobile phone dependency. For this study, I used data from the first grade of junior high school during the 7th (2016) Korean child and youth panel survey provided by Korea Youth Policy Institute. A total of 1,937 people were selected as the final target except those who do not have a mobile phone. The analysis method was SPSS 23.0 and AMOS 20.0. As a result of the study, First, the higher the depression of adolescents, the higher the dependence on mobile phones. Second, the social withdrawal and depression of adolescents have a significant impact on mobile phone dependence through self-esteem. In conclusion, I would like to provide policy data so that youths can develop and implement preventive programs that can prevent personality education and erroneous mobile phone dependency that can develop healthy and positive growth.

• IMMUNE NETWORK
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• v.12 no.1
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• pp.18-26
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• 2012

Background: Vitamin C is an essential nutrient for maintaining human life. Vitamin C insufficiency in the plasma is closely related with the development of scurvy. However, in vivo kinetics of vitamin C regarding its storage and consumption is still largely unknown. Methods: We used $Gulo^{-/-}$ mice, which cannot synthesize vitamin C like human. Vitamin C level in plasma and organs from $Gulo^{-/-}$ mice was examined, and it compared with the level of wild-type mice during 5 weeks. Results: The significant weight loss of $Gulo^{-/-}$ mice was shown at 3 weeks after vitamin C withdrawal. However, there was no differences between wild-type and vitamin C-supplemented $Gulo^{-/-}$ mice (3.3 g/L in drinking water). The concentration of vitamin C in plasma and organs was significantly decreased at 1 week after vitamin C withdrawal. Vitamin C is preferentially deposited in adrenal gland, lymph node, lung, and brain. There were no significant changes in the numbers and CD4/CD8 ratio of splenocytes in $Gulo^{-/-}$ mice with vitamin C withdrawal for 4 weeks. And the architecture of spleen in $Gulo^{-/-}$ mice was disrupted at 5 weeks after vitamin C withdrawal. Conclusion: The vitamin C level of $Gulo^{-/-}$ mice was considerably decreased from 1 week after vitamin C withdrawal. Vitamin C is preferentially stored in some organs such as brain, adrenal gland and lung.