• Journal of the Korean Home Economics Association
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• v.40 no.8
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• pp.191-206
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• 2002

The purpose of this study was to explore the effects of adolescent attachment to mothers and peers, self-esteem and impulse control on delinquency. The subjects were 624 eighth and eleventh grade students in Busan. The subjects rated themselves on questionnaires regarding attachment to mothers and peers, self-esteem, impulse control and latent delinquency. The major findings of this study were as follows; 1) Male adolescent delinquency increased with grade. But no grade difference was found in female adolescent delinquency. And male adolescent had more delinquency than female adolescent. 2) Grade had a direct and indirect effect through attachment to peers and impulse control on male adolescent delinquency and was the first positive contribution factor. Impulse control had a direct negative effect on male adolescent delinquency. Attachment to mothers had an indirect negative effect through self-esteem on male adolescent delinquency. Attachment to peers had an indirect negative effect through self-esteem and impulse control on male adolescent delinquency. Self-esteem had an indirect negative effect through impulse control on male adolescent delinquency. 3) Attachment to mothers had a direct and indirect effort through impulse control on female adolescent delinquency and was a first negative contribution factor. Impulse control had a direct negative effect on female adolescent delinquency. Attachment to peers had an indirect negative effect through impulse control on female adolescent delinquency. Grade had an indirect negative effect through impulse control on female adolescent delinquency. Self-esteem had no effect on female adolescent delinquency.

• Molecular & Cellular Toxicology
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• v.3 no.3
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• pp.159-164
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• 2007

Stimulation of epidermal growth factor receptor (EGFR) is essential in signaling pathway of tumor cells. Thus, EGFR has intensely studied as an anticancer target. We developed hologram quantitative structure activity relationship (HQSAR) models for data set which consists of tricyclic azepine derivatives showing inhibitory activities for EGFR. The optimal HQSAR model was generated with fragment size of 6 to 7 while differentiating fragments having different atom and connectivity. The model showed cross-validated $q^2$ value of 0.61 and non-cross-validated $r^2$ value of 0.93. When the model was validated with an external set excluding one outlier, it gave predictive $r^2$ value of 0.43. The contribution maps generated from this model were used to interpret the atomic contribution of each atom to the overall inhibition activity. This can be used to find more efficient EGFR inhibitors.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.53-53
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• 2018

Thermoelectric materials can convert directly waste heat to electricity and vice versa. The improvement of the thermoelectric efficiency strongly depends on the dimensionless figure of merit, $ZT=S^2{\sigma}T/{\kappa}$, where S is the Seebeck coefficient, ${\sigma}$ is the electrical conductivity, T is the absolute temperature, and ${\kappa}$ is the thermal conductivity. The thermal conductivity consists of the electronic contribution (${\kappa}_e$) and phonon contribution (${\kappa}_{ph}$). It is very challenge to increase the power factor, $S^2{\sigma}$ and to reduce the thermal conductivity simultaneously because the power factor and electronic thermal conductivity are coupled. One strategy is to decrease the phonon thermal conductivity. The phonon thermal conductivity can be decreased by controlling the grain size and structural defects such as dislocations and twinning. In order to achieve enhancements in thermoelectric efficiency, microstructures that can form numerous interfaces have been investigated intensively for controlling the transport of charge carriers and heat carrying phonons. In this presentation, we report the heterogeneous microstructure of $Mg_2Si_{0.6}Sn_{0.4}$ thermoelectric materials and investigation of its influence on thermoelectric properties.

• Journal of the Korean Home Economics Association
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• v.39 no.8
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• pp.37-52
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• 2001

The purpose of this study was to explore the relationships of mother's childrearing behavior, children's behavior problems, locus of control and peer victimization. The subjects were 360 children of 4th and 6th grade and their mothers. The instruments were Peer Victimization Scale, CBCL, Locus of Control Scale for Children, Childrearing Behavior Scale. The major findings of this study were as follows; (1) The type of peer victimization had a significant difference between girls and boys. That is, boys were more focused on overt victimization than girls. There was no significant gender difference in relational victimization, And there was no significant grade difference in overt and relational victimization. (2) Mother's rejection-restriction childrearing behavior, children's social withdrawal behavior problems, extemal locus of control predicted children's peer victimization. 24% of the variance of children's peer victimization was explained by these variables. (3) Mother's rejection-restriction childrearing behavior was the first contribution factor and had a direct and indirect effect through children's locus of control on children's peer victimization. And children's social withdrawal behavior problems was second contribution factor and had a direct effect on children's peer victimization. Children's locus of control had a direct and indirect effect through children's social withdrawal behavior problems on children's peer victimization. Mother's warmth-acceptance and permissiveness-nonintervention childrearing behavior had indirect effect through children's locus of control on children's peer victimization.

• Journal of Integrative Natural Science
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• v.10 no.3
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• pp.141-147
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• 2017

Vascular endothelial growth factor (VEGF) is an important signaling protein involved in angiogenesis, which is the formation of new blood vessels from pre-existing vessels. Consequently, blocking of the vascular endothelial growth factor receptor (VEGFR-2) by small molecule inhibitors leads to the inhibition of cancer induced angiogenesis. In this study, we performed a two dimensional quantitative structure activity relationship (2D-QSAR) study of 38 N-Phenyl-N'-{4-(4-quinolyloxy) phenyl} urea derivatives as VEGFR-2 inhibitors based on hologram quantitative structure-activity (HQSAR). The model developed showed reasonable $q^2=0.521$ and $r^2=0.932$ values indicating good predictive ability and reliability. The atomic contribution map analysis of most active compound (compound 7) indicates that hydrogen and oxygen atoms in the side chain of ring A and oxygen atom in side chain of ring C contributes positively to the activity of the compounds. The HQSAR model developed and the atomic contribution map can serve as a guideline in designing new compounds for VEGFR-2 inhibition.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.1
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• pp.144-154
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• 1997

For design of early childhood children's footwear, this study was to analyze the foot type by factor analysis and cluster analysis. This study was performed 200 male and 200 female early childhood children from 3 to 6 years, reported in part 1. The result was as follows : 1. There are no significant differences concerning significances, factor loading, eigenvalues, and contribution rates of factor among the results abtained by analyzing the male, female and both sexes data. 2. The 1st factor signifies the size factor that represents total foot mass. The average scores of the 1st factor significantly increase with age in both sexes, and those scores of male are significantly higher than those of female. 3. The End factor signifies the height of Tarsal, Heel and Arch. The average scores of the 2nd factor significantly increase with age in both sexes, and there are no significant differences between the average scores of male and female's except the age 3. 4. The 3rd factor signifies the shape of Metatarso-phalanx angle. The average scores of the 3rd factor significantly decrease with age in female. 5. There are four clusters selected by fastcluster in every age group. The characteristics of four clusters of every age group are different significantly.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.771-782
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• 2021

Social entrepreneurship plays a key role in organizational performance, and social contribution activities are related to organizational members' perception of social enterprise value and performance sharing. The purpose of this study is to verify the mediating effect of social contribution activities in the relationship between social entrepreneurship and organizational performance. For the study, a questionnaire survey was conducted on members of social enterprises, and data of 186 valid copies were used for statistical analysis. Statistical analysis used reliability of measurement variables, confirmatory factor analysis, correlation analysis, and mediating effect analysis. The results of the study are as follows. First, there was a significant correlation between social entrepreneurship, social contribution activities, and organizational performance. Second, social entrepreneurship has a significant correlation with organizational performance. Social purpose and initiative, sub-factors of social entrepreneurship, had a significant influence on organizational commitment. Third, social contribution activities showed a significant relationship with organizational performance. Fourth, in the relationship between social entrepreneurship and organizational performance, social contribution activities showed a partial mediating effect. This suggests that social contribution activities play an important role in improving the performance of social enterprises.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.E2
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• pp.57-68
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• 2006

Four intensive seasonal sampling campaigns between October 1998 and October 1999 were undertaken at an urban site of Chongju, in which polyurethane foam (PUF) sampler was used to collect particulate- and vapor-phase polycyclic aromatic hydrocarbons (PAHs). The contribution to total (particulate+vapor) PAH concentration by the vapor phase component exceeded the particulate phase contribution by factor of ${\sim}2.6$. Summed concentrations of phenanthrene (30.9%), pyrene (16.6%), naphthalene (11.3%) and fluoranthene (11.0%) account for significant amounts of the vapor-phase, while chrysene (12.5%), benzo[b]fluoranthene (11.6%), indeno[123-cd]pyrene (9.9%), benzo[ghi]perylene (9.5%), benzo[k]fluoranthene (9.4%), pyrene (8.9%), and benzo[a]pyrene (8.3%) are found to be the most common PAH compounds in the particulate phase. The results from application of principal component analysis to particulate-phase PAH data demonstrate that a combination of PAH and $PM_{2.5}$ inorganic data is a more powerful tracer of emission sources than PAH species data alone. Particulate-phase PAH species were found to be associated predominantly with emissions from diesel engine vehicles and incineration.

• The KSFM Journal of Fluid Machinery
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• v.14 no.1
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• pp.42-47
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• 2011

Measurement uncertainty analysis of fuel flow using turbine flowmeter was performed for the case of altitude engine test. SAE ARP4990 was used as the fuel flow calculation procedure, as well as the mathematical model for the measurement uncertainty assessment. The assessment was performed using Sensitivity Coefficient Method. 11 parameters involved in the calculation of the flow rate were considered. For the given equipment setup, the measurement uncertainty of fuel flow was assessed in the range of 1.19~1.86 % for high flow rate case, and 1.47~3.31 % for low flow rate case. Fluctuation in frequency signal from the flowmeter had the largest influence on the fuel flow measurement uncertainty for most cases. Fuel temperature measurement had the largest for the case of low temperature and low flow rate. Calibration of K-factor and the interpolation of the calibration data also had large influence, especially for the case of very low temperature. Reference temperature, at which the reference viscosity of the sample fuel was measured, had relatively small contribution, but it became larger when the operating fuel temperature was far from reference temperature. Measurement of reference density had small contribution on the flow rate uncertainty. Fuel pressure and atmospheric pressure measurement had virtually no contribution on the flow rate uncertainty.

• Knowledge Management Research
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• v.15 no.4
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• pp.189-206
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• 2014

Knowledge management is considered an important factor for competitive advantage and sustainability for firms. As many knowledge management systems failed to achieve the desired results, enterprise social media (ESM) has received considerable attention as an alternative solution for knowledge sharing within a firm. This paper attempts to investigate the influence of various aspects of ESM on knowledge sharing. While previous literature mainly focused on structural aspects of ESM, this study focuses on social psychological aspects, such as social connectedness, social awareness, and social presence, along with reputational aspects (such as self-presentation). Further, in order to clarify knowledge sharing behavior, this study classifies knowledge sharing behavior into two categories, knowledge contribution and knowledge acquisition. The data used in this study was collected from 179 individuals who have experience in their own ESM. The results show that both social connectedness and self-presentation positively influence the two types of knowledge sharing behavior, i.e., acquisition and contribution. Meanwhile, social awareness turns out to be a significant determinant of knowledge contribution only. Contrary to our expectations, however, social presence does not significantly influence knowledge sharing behavior.