• Journal of Astronomy and Space Sciences
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• v.25 no.2
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• pp.149-156
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• 2008

Forbush Decreases (FDs) are representative events of abrupt decrease in galactic cosmic ray intensity. They are known to be strongly associated with solar wind events such as interplanetary shock (IP shock) and magnetic cloud (MC). In order to examine effectiveness of the MC on FDs, I studied the 44 MCs that occurred during the 2 years from 1998 to 1999 and investigated the properties of interplanetary magnetic field (IMF) and solar wind. As a result, I found that 11 out of 44 MCs are associated with the FDs. In particularly, it is noted that the FDs are driven by the IP shock sheaths which are associated with over 13 nT of IMF magnitude, 3 nT of IMF turbulence, and 550km/s of solar wind speed. This result indicates that magnetic cloud and its interplanetary shock sheath work as a modulator of the cosmic ray intensity.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.51-58
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• 2018

This study aimed to find the related factors of nursing students' self-efficacy(including general self-efficacy and social self-efficacy), self-leadership and academic performance. Collected data were analyzed using SPSS 19.0. The general self-efficacy scores of the subjects in who're admitted according to aptitude, higher school grades, extroverts, and higher leadership were significantly higher than those who weren't. The social self-efficacy scores were significantly higher in younger ages, extroverts and higher leadership. Self-leadership was higher in those who're admitted according to aptitude. Academic performance was significantly higher in the females and higher school grades. Social self-efficacy was positively correlated with self-leadership, and negatively with academic performance. Explanation rate of sex, general self-efficacy and social self-efficacy on academic performance was 10.5%. These results can be applied as a basis for developing guidelines of nursing students' self-efficacy, self-leadership and academic performance after repeated studies.

• Journal of the Korean Magnetics Society
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• v.7 no.6
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• pp.308-313
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• 1997

The magnetoresistance (MR) and the saturation field behavior of the CoFe-Ag nano granular films as a function of the ferromagnetic underlayer and overlayer materials were investigated. The maximum MR ratio of 25.7 % and the saturation field of 2.1 kOe in the as-deposited 3000 $\AA$ $(Co_{92}Fe_8)_{31}Ag_{69}$ single alloy films at room temperature were obtained. The MR ratio and the saturation field of the 100 $\AA$ alloy film were 1.2 % and 5.2 kOe, respectively. Those of the sandwiched alloy films of 200 $\AA$ thick with the Fe under and overlayer of 100 $\AA$ were 11 % and 1.8 kOe respectively. The reduction of saturation field in the sandwiched alloy films is due to the exchange coupling between the ferromagnetic layers and the alloy layer. Among the Fe and FeNi, the more effective materials to reduce the saturation field of the sandwiched alloy films was Fe.

• Journal of the Korean Magnetics Society
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• v.20 no.3
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• pp.100-105
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• 2010

For predicting magnetic signals due to the remanent magnetization distributed on a ferromagnetic ship hull, this paper presents an efficient methodology for solving inverse problems, where the material sensitivity analysis based on the continuum mechanics is combined with the equivalent magnetic models. To achieve this, the 3D magnetic charge model and the magnetic dipole moment model are introduced and material sensitivity formulae applicable to each equivalent model are derived. The formulae offer the first-order gradient information of an objective function with respect to the variation of the magnetic charge or magnetic dipole and so an optimal solution can be easily obtained regardless of the number of design variables. To validate the proposed method, the numerical results are comparison with the real measurements of a mock-up model.

• Journal of the Korean Magnetics Society
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• v.12 no.2
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• pp.46-50
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• 2002

Soft magnetic Mumetal thin film was fabricated under magnetic field at various substrate temperatures. High vacuum annealing was carried out at 200$\^{C}$ during 1 hr. The in-plane anisotropy of Mumetal thin film was determined from hysteresis loops measured by VSM when the sample axis varied from the field direction from 0°to 180°. As the substrate temperature increases, the coercivity in easy direction decreases, but uniaxial anisotropy deviates from the field direction. After vacuum annealing at 200$\^{C}$ for 1 hr, the uniaxial anisotropy is improved irrespective of substrate temperature. When the substrate temperature was 50$\^{C}$, the anisotropy field is 4.3 Oe. As the substrate temperature increases anisotropy field decreases. Uniaxial anisotropy of Mumetal thin film was formed best at 50$\^{C}$ before and after annealing.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.487-494
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• 2011

This paper is to investigate the efficacy of cyber education by self-assessment strategy. Self-assessment strategy contains self-monitoring function and self-control function. 202 students of online university attended and analyzed with frequency, correlation, t-test, Paired t-test. The major findings were as follows. The learners who experienced self-assessment in the initial stage of class had higher changes in social distance to the mentally disabled people positively than the learners who didn't experienced that. This self-assessment strategy can be assumed that it is effective strategy to improve e-learning efficacy and it will contribute to self-directed education for enhancement of on-line education.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.311-320
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• 2016

Purpose: A descriptive study to focus the life style, self-efficacy and health promotion activity of university students, to analyze the phase-to-phase relationship between and impact on health promoting behaviors. Method: At K University among 225 students on 22-26th August 2014. Self-management and self-efficacy of [24] and health promotion activities of [29] are used for the measuring tools. Results: Health promotion activity with general characteristics is major, living and allowed time is a significant different. Between health promotion activity and self management of health variables were shown moderate correlation. Self-efficacy was too. The relevant explanatory factors influencing the self management of health promotion activities was found to be 64.0%. Conclusion: This study suggests that to improve the health promotion activities, measures to promote self-management and self-efficacy are required and the development of health promotion program is needed.

• Geophysics and Geophysical Exploration
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• v.16 no.2
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• pp.97-105
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• 2013

Nuclear magnetic resonance (NMR) logging has become an important technique for formation evaluation, detecting interaction signals between H protons and applied magnetic fields. Measured decay signals called relaxation, contain important information about density of H protons and different decay rate due to its fluid type in the sensitive area. Thus, petrophysical information such as porosity, permeability and wettability can be estimated through the interpretation of the decay signals. Many researches on random walk simulation have been published, since a simulation method based on random walk for solving exponential decays was adapted in the early of 1950. This study first makes a review on NMR simulation researches, explains two most important methods: simulation with or without considering magnetic field gradient. Lastly, the study makes a comparison between NMR simulation responses with and without magnetic field gradient to show the importance to consider magnetic gradient to analyze the effects of magnetic gradients on NMR responses.

• Korean Journal of Childcare and Education
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• v.9 no.5
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• pp.489-511
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• 2013

The main purpose of this study is to examine the effects of preschoolers' levels of playfulness, self-esteem and self-regulation on their self-determination. Furthermore, the mediational effects of the children's self-esteem in the relationship between their playfulness and self-determination. To meet the purposes of this study, 126 preschoolers aged 6-7 years old who attended early childhood education and care settings were sampled. Data on the preschoolers' self-esteem, self-regulation, and self-determination were assessed by their teachers, and their playfulness was observed by one of the researchers in this study. The main results of this study were as follows. The most influential variable on the young children's self-determination was found to be their levels of self-esteem. Also, the preschoolers' self-esteem mediated the effects of the playfulness on their self-determination. Implications for research and practice were discussed along with the results of this study.

• Journal of Digital Convergence
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• v.14 no.9
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• pp.461-470
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• 2016

The purpose of this study is to identify relationships among psycho-social maturity, self-efficacy for contraceptive, and sexual assertiveness to see which factors influence sexual assertiveness in male university students. Data were collected from 200 male university students in A city from July 1 to 30, 2015. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression. Significant correlations were found among Psycho-Social Maturity, Self-efficacy for Contraceptive, and Sexual Assertiveness. Meaningful variables that influenced Sexual Assertiveness were Self-efficacy for Contraceptive and Psycho-Social Maturity, and the total explanation power was 33%. In conclusion, development of sex education program to increase Sexual Assertiveness of male university students based on the influencing factors is needed.