• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.4
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• pp.236-240
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• 2014

Induction motor requires a rotating magnetic for rotation. Current required to generate the rotating magnetic field is magnetizing current. This magnetizing current is associated with the reactive power. This reactive power must be supplied from source side. Therefore, the power factor of the induction motor is low. So, the capacitor is installed on the motor terminals to compensate for the low power factor. Power supply company has recommended to maintain a high power factor to the customer. If the capacitor current is greater than the magnetizing current of the motor, there is a possibility that the self-excitation occurs. So it is necessary to calculate the optimal capacity capacitor current does not exceed the magnetizing current. In this study, we first compute the no-load current and the reactive power of the induction motor and then calculates the limit of the maximum power factor without causing self-excitation.

• Journal of Power Electronics
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• v.12 no.5
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• pp.699-707
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• 2012

This paper proposes a single-stage half-bridge electronic ballast with a high power factor using only a single coupled inductor. Compared to conventional high power factor electronic ballasts, the proposed ballast is a simpler circuit with a low cost and a high reliability. The proposed ballast is made up of a power-factor-correction (PFC) circuit and a self-oscillating class-D inverter. The PFC and inverter stages of the proposed ballast are simplified by sharing only a single coupled inductor and two common switches. The proposed PFC circuit can achieve a high power factor and low voltage stresses of the switches. A saturable transformer in the self-oscillating class-D inverter determines the switching frequency of the ballast. Experimental results obtained on a 30W fluorescent lamp are discussed.

• Journal of Information Science Theory and Practice
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• v.3 no.2
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• pp.42-57
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• 2015

Purpose. : The present study is an attempt to find out the impact of self-citations on Impact Factor (IF) across disciplines. The study examines the number of research articles published across 27 major subject fields covered by SCImago, encompassing as many as 310 sub-disciplines. The study evaluates aspects like percentage of self-citations across each discipline, leading self-citing countries and continents, and the impact of self-citation on their IF. Scope. : The study is global in nature, as it evaluates the trend of self-citation and its impact on IF of all the major subject disciplines of the world, along with countries and continents. IF has been calculated for the year 2012 by analyzing the articles published during the years 2010 and 2011. Methodology/Approach. : The study is empirical in nature; as such, statistical and mathematical tools and techniques have been employed to work out the distribution across disciplines. The evaluation has been purely under-taken on the secondary data, retrieved from SCImago Journal and Country Ranking. Findings. : Self-citations play a very significant part in inflating IF. All the subject fields under study are influenced by the practice of self-citation, ranging from 33.14% to 52.38%. Compared to the social sciences and the humanities, subject fields falling under the purview of pure and applied sciences have a higher number of self-citations, but a far lesser percentage than the social sciences and humanities. Upon excluding self-citations, a substantial amount of change was observed in the IF of subject fields under study, as 18 (66.66%) out of 27 subjects fields faced shuffle in their rankings. Variation in rankings based on IF with and without self-citation was observed at subject level, country level, and continental level.

• Journal of the Korea Society of Computer and Information
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• v.22 no.11
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• pp.151-160
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• 2017

IIn this paper, I investigate the effect of special education teachers' self-leadership on job-satisfaction. The data was collected from 141 special education teachers to analyze the correlations between self-leadership, job and life satisfaction. In addition, another purpose is to analyze how self-leadership influence on job satisfaction (human relationship, assigned tasks) and life satisfaction. The results are shown as follows. First, self-expectation and goal setting, self-expectation and human relationship, human relationship and assigned tasks have meaningful correlation. Second, self-expectation and self-rewarding are sub-factors of self-leadership that have great influence on human relationship which is a subordinate factor of job satisfaction and assigned tasks. Third, self-expectation and self-rewarding are factors of self-leadership that have a great influence on life satisfaction. Finally, it shows that self-leadership has an effect on life satisfaction through assigned task, which is a factor of job satisfaction. However, through human relationship, self-leadership does not have a meaningful effect on life satisfaction. This study is significant by finding sub-factors which influence special education teacher's self leadership, job satisfaction and life satisfaction by using Bootstrap method.

• Korean Journal of Child Studies
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• v.22 no.3
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• pp.1-15
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• 2001

The development of this inventory for measuring the parenting self-efficacy of Korean mothers took place in Seoul with 473 mothers of 5th and 6th grade children. Means, %, ${\chi}^2$, Cramer's V, Cronbach's ${\alpha}$, Split-half Reliability, factor analysis and Pearson's r were used for data analysis. Five parenting self-efficacy factors were extracted from the 37 items developed for this study. Subscales were General Parenting Self-Efficacy, Health, Communication, Education, and Control. Criterion Validity of the 37 items was confirmed by a significant correlation with the Shin's parenting self-efficacy(r=.71). Internal consistency of this scale was high (Cronbach's ${\alpha}=.92$), including internal reliability of subscales. Factor validity was satisfactory at .65 - .86. These results confirm this scale as a valid and reliable measure of the parenting self-efficacy of Korean mothers.

• Journal of the Korean Home Economics Association
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• v.36 no.4
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• pp.121-136
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• 1998

The purpose of this study was to investigate the causal resationships between children's learned helplessness, self-evaluation and the home environment which included the family's socio-economic status, parent's achieving pressure and maternal child rearing behavior. The results were as follows; The socio-economic status of home influenced on the parent's achieving pressure, maternal child rearing behavior and children's self-evaluation, but didn't influence children's learned helplessness. Parent's achieving pressure had a negative correlation with the maternal child rearing behavior and influenced children's learned helplessness, but did not influence children's self-evaluation. Maternal child rearing behavior influenced children's self-evaluation, but did not influence children's self-evaluation. Maternal child rearing behavior influenced children's self-evaluation, but did not influence children's learned helplessness directly. Children's self-evaluation had the strongest direct impact on children's learned helplessness. This was found to be a mediating factor between home environmental factor and children's learned helplessness.

• Journal of the Korean Home Economics Association
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• v.36 no.12
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• pp.73-86
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• 1998

In this study, we compared how different the self-perception and the daily hassels between the Korean and American children. The subjects were 706 fifth and seventh grade students. Data were obtained by administrating a questionnaire. The instruments used for this study were self-perception profile for children scale(SPPC) and stress scale. 1. All the SPPC factors for Korean children was significantly lower than those for American children. The SPPC fators for American children didn't show any significant differences by grades. But for Korean children seventh graders showed significantly lower SPPC than fifth graders. 2. The most significant factor to predict the golbal self-worth was physical appearance for boys and girls. Self perception for physical appearance is more influential factor than scholastic competence to form the positive self-perception for both boys and girls. 3. The daily hassels for Korean children were significantly higher than those for American childredn. Also daily hassels for seventh graders were significantly higher than those for fifth graders. 4. Daily hassels global self worth correlated negatively. When the level of stress was increased, the global self-worth was decreased.

• Journal of Korean Academy of Nursing
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• v.45 no.1
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• pp.64-75
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• 2015

Purpose: This study was designed to construct and test structural equation modeling on healthy menopausal transition in middle-aged women in order to identify variables affecting healthy menopausal transition. Methods: Participants, 276 women, 45 to 60 years of age, with menopausal symptom score higher than 5 on the Korean version of Menopause Rating Scale, were recruited in three cities and one county of Gyeongnam Province. Research data were collected via questionnaires and analysed using SPSS version 18.0 and AMOS version 20.0. Results: After confirmatory factor analysis, one of the observed variables was excluded due to relatively low factor loading. The model fit indices for the hypothetical model were suitable for the recommended level: GFI=.93, CFI=.92, RMSEA=.05. Self-efficacy, self-differentiation, and menopausal symptoms explained 67.7% of variance in menopausal transition, and self-differentiation was the most influential factor for menopausal transition. Self efficacy and menopausal symptoms explained 9.6% of variance in menopausal management, although "menopausal symptoms" was not significant. Conclusion: These results suggest that nursing interventions to improve self-differentiation, self efficacy, menopausal management and decrease menopausal symptoms are critical for healthy menopausal transition in middle-aged women. Continued development of a variety of community-based nursing interventions to facilitate healthy menopausal transition is suggested.

• The Research Journal of the Costume Culture
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• v.21 no.4
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• pp.562-575
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• 2013

The purpose of this study was to test the determinants of fashion savvy. As determinants, this study examined fear of negative evaluation by others and self esteem as subject-related variables and consumer confidence in fashion decisions as the product-related variable. It was hypothesized that fear of negative evaluation and self esteem influence fashion savvy both directly and indirectly through consumer confidence in fashion decisions. Data were gathered by surveying university students in Seoul metropolitan area, using convenience sampling, and 311 questionnaires were used in the statistical analysis. In analyzing data, factor analysis and path analysis were conducted. Tests of the hypothesized path show that one factor of fear of negative evaluation and self esteem influence fashion savvy directly and indirectly through consumer confidence in fashion decisions. More specifically, 'fear of negative impression and judgment' factor negatively influences 'marketing literacy' and 'consumer selfefficacy' of fashion savvy, whereas self-esteem positively influences 'consumer self-efficacy' of fashion savvy. In addition, consumer confidence in fashion decisions influences all six factors of fashion savvy. The implications of these findings and suggestions for future study are also discussed.

• Korean Journal of Human Ecology
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• v.3 no.2
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• pp.13-26
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• 2000

The purpose of present study were to find the general trends of mate selecting factors and. marital satisfaction. concentrated on married women, to examine the difference among mate selection factors and marital satisfaction according to socio-demographic variables and Psychological variables and to analyze the effects of these variables influencing marital satisfaction. The subjects were 276 wives, living in Kwangju that having passed under S years after marriage without divorce experience. The major findings were as follows . 1. In mate selection, factor of high-degree was personality. view of value. personal relations, achievement, emotional mature. self-differentiation. degree of affection's expression. sense of humor, charms and condition of health Respondents'marital satisfaction score showed 91.75 and this score was higher than median score(62.5) 2. The external factor of mate selection showed significant difference according to degree of education. career. order. and sex-role attitude. The internal factor of mate selection showed significant difference according to degree of education, career, order, self-differentiation, self-esteem, and sex-role attitude 3. As correlating mate selectional factors to marital satisfaction, the significance appears in the mate's personality. view of value, emotional mature. personal relations. self-differentiation, condition of health. achievement. charm, sense of humor and degree of affection's expression. 4. Married women's marital satisfaction was influenced by self-esteem, personality and child's number that were explained about 38% by these variables. In conclusion, to happy marital life must be loved her own self. and above all considered internal factors like personality than external factors in mate selection.