• Journal of Power Electronics
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• v.15 no.2
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• pp.567-575
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• 2015

An improvement in the current fed parallel resonant half bridge (CFPRHB) circuits used in fluorescent lamp electronic ballasts is provided in this paper. The CFPRHB belongs to the self-oscillating family which includes the current fed push-pull and series resonant inverters, most of which are used in instant-start applications. However, many failure modes are related to the bypass capacitor according to an analysis of failed samples. In this paper, the operating functions of the existing topology in the steady state are analyzed and the main root cause of failure modes has been found. Comparisons between the two topologies are conducted in terms of the voltage stress of the bypass capacitor as well as the thermal and performance of the ballasts to verify the advantages of the proposed topology. It is found that the improved topology is capable of enhancing the reliability and reducing the cost of products without having a negative influence on the system performance.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.3
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• pp.117-121
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• 2005

Power system restoration following a massive blackout starts with re-energizing primary transmission lines at first. Some factors such as Ferranti effect, and line charging reactive power should be considered in this stage. Severe overvoltage may be induced by the Ferranti effect at the lines since it would be usually no load condition. And lack of capacitive reactive power will cause the self-excitation. This paper presents a new precise algorithm to analyze the primary restorative transmission system focused on the two major static overvoltage problems during the early restoration process.

• Korean Journal of Computational Design and Engineering
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• v.2 no.2
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• pp.85-92
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• 1997

An axial flow fan design system has been made by integrating the self-developed programs and I-DEAS. By using the system, an axial flow fan was designed, manufactured and verified through the wind tunnel experiments in coorperation with a refrigerator appliance division. It has been shown that the optimal design without the ambiguity of the design parameters can be possible by the three-dimensional flow simulations using a self-developed CID code, FANS-3D. (Flow Analysis code using Navier Stokes aguations in Three-Dimensional curvilinear coordinates). By virtue of the fluency of the data flow, an optimally designed fan which satisfies design conditions can be selected in a short time and less cost. The manufacturing processes of a Mock-up and an injection molding die have been automated through the self-made interface programs which connnect from the start to the end. It has been shown that the newly developed fan by this system has a superior performance characteristics to an existing fan.

• Journal of Agricultural Extension & Community Development
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• v.29 no.4
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• pp.251-264
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• 2022

This study aimed to identify the factors that influence young entrepreneurs' desire to start a smart farm business. Young entrepreneurs' entrepreneurial self-efficacy, entrepreneurial intention, entrepreneurship, and Entrepreneurial opportunity recognition were modeled structurally, and the mediating effect of entrepreneurship and entrepreneurial opportunity recognition was investigated. Data were conducted from 159 usable questionnaires. The following are the findings of this study. Entrepreneurial self-efficacy did not have a significant effect on entrepreneurial intention, but entrepreneurship and entrepreneurial opportunity recognition were found to have a mediating effect on entrepreneurial intention. Therefore, the preparation of training programs to encourage entrepreneurship or the dissemination of pertinent information to identify opportunities should take precedence over immediate startup.

• Journal of Information Technology Applications and Management
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• v.30 no.3
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• pp.15-35
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• 2023

Considerable agreement exists about the importance of promoting entrepreneurship in both developed and developing countries. In less developed countries, governments see entrepreneurship as a way to stimulate economic development and tackle serious economic and social challenges. So how can countries encourage young people to become entrepreneurs? Research confirms that intentions play an important role in the decision to start a new firm and many factors influence that intentions. The purpose of the study was to investigate the antecedents to entrepreneurship behavior with particular attention to moderating role of social support and entrepreneur self-efficacy. The study covered 116 business students of undergraduate and post graduate level studying under different universities in Kathmandu, Nepal. The questionnaire for data collection was distributed in college groups via WhatsApp and viber with the support and permission from the college administration. The study design used was correlational with a sampling procedure of convenience. The study only showed the impact of attitude to entrepreneurship behavior as well as moderating effect of social support was also observed.

• Korean Journal of Childcare and Education
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• v.12 no.5
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• pp.17-45
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• 2016

This study aimed to investigate the effect of a young children's happiness program in relation with the Nuri curriculum on young children's happiness and self-esteem. Study subjects included 37 children aged 5 (experimental group 20, comparative group 17) enrolled in A day care center and D day care center located in K district, Seoul. As for the research procedure, an experiment was conducted 48 times in 18 weeks, and the experimental group carried out the children's happiness program linked with the Nuri curriculum. In contrast, the comparative group conducted general activities focusing on the subjects according to the Nuri curriculum. Study results show that there was a significant difference amongst 9 sub-domains related to young children's happiness (health, emotion, immersion, recognition and achievement, parent-child relationship, teacher-child relationship, peer relationship, spirituality, life satisfaction) and 3 sub-domains related to self-esteem (start and spirit of independence, sociality emotionality, academic achievement). Results of this study prove that the children's happiness program in relation with the Nuri curriculum is effective for increasing young children's happiness and self-esteem, and could be used as preliminary data for the possibility of a happiness program in early childhood education settings and happiness education in the future.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.21 no.4
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• pp.362-369
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• 2014

Purpose: The purpose of the study was to investigate factors that influence university women with eating problems. Methods: Study participants were 307 women from two universities. Self-report questionnaires which included items on eating problems, satisfaction with body shape, self-esteem, body mass index, and weight control methods were used. Data were analyzed using independent t-tests, ${\chi}^2$ tests, and a multiple binary logistic regression. Results: About 20% of the undergraduate women were experiencing eating problems. The problematic eating group showed more dissatisfaction with body shape than the normal eating group, and used more diets, fasting, diet-products, and uretics/laxatives to control body weight. Significant predictors for the problematic eating group were diets, diet-products, BMI, self-esteem and dissatisfaction with body shape. The strongest predictors were diets; risk for women university students who had been on a diet was 15 times higher than their counterparts. Conclusion: It is pertinent for health professionals to start intervention programs to educate university women with eating problems. The contents should include information on healthy weight control methods, improving satisfaction with body shape and self esteem, as well as creating social atmosphere about healthy body shape for women.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.523-534
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• 2017

The purpose of this study was to examine the effects of social bonding on self-competence in the juvenile delinquency on the mediating effect of self-esteem. The data of 908 juvenile inmates in a Study on Measures to Develop Entrepreneurship Education Model and to Encourage Start-up for Youth(2015) by the National Youth Policy Institute were analysed. The results of the study are: (1) social bonding was found a key factor affecting the self-competence, (2) their social bonding affects self-esteem, (3) self-esteem affects self-competence, (4) self-esteem was proved to have a mediating effect between the effects of social bonding and self-competence. The implications and limitations are reviewed, as are the suggestions for future research.

• Korean Journal of Social Welfare
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• v.63 no.4
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• pp.5-31
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• 2011

This study explored how young people with disabilities experience self-determination in their lives. This study employed a grounded theory approach involving 10 undergraduate students with cerebral palsy or physical disabilities, in their early 20's, and individual interviews. The experience relating self-determination of the participants seemed to start with "wanting to do things at their will as they grow up". The participants reported experiencing "yearning to attain self-actualization overcoming disabilities" in the context of "disability-related social limitation", "divided opinions between the participants and their parents", and "limitation in financial and psychological resources". The emerging strategies to attain self-actualization included "active coping", "avoiding confrontation", and "conditional acceptance". Intervening conditions to formation of the strategies included ”challenging spirits towards prejudice about disability", "autonomous tendencies", "taking the most of social support" and "parenting attitudes of their parents". In the process of seeking to attain self-actualization, these participants experienced "self-maturation" and "the sense of guilt towards their parents". The findings emerged from the study was that there are three stages in the process young people went through in self-determination. The stages consist of "perceiving their needs and obstacles for self-determination", "problem solving", and "perceiving their growth". In addition, four self-determination patterns are derived from this data: "breaking through", "multi-strategic", "moderate", and "acceptive". This study suggested some theoretical and prctical implications needed to facilitate self-determination of youth with disabilities.

• Journal of Korea Society of Digital Industry and Information Management
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• v.15 no.1
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• pp.133-155
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• 2019

The economic growth has made our lives more prosperous than the past, and the development of science fueled the era of 100-year lifespan. It is now distinct to us that preparation for life after retirement is not a choice but an imperative. In the meantime, outplacement programs have driven many to challenge and start a new chapter in life. This paper measures the characteristics of outplacement programs based on the self-determination factors; empirically examines how those characteristics influence on learning performance through self-efficacy and psychological well-being; concludes by proposing effective and productive ways for young adults and senior employees who are in search for new jobs. To test the research hypothesis, a survey was conducted among job searchers who have been previously provided with outplacement programs. The results are as follows: First, self-perceived autonomy has significant influences on self-efficacy and psychological well-being. Second, self-perceived competency has significant influences on self-efficacy and psychological well-being. Third, perceived relationship has no significant influence on self-efficacy and psychological well-being. Fourth, self-efficacy showed significant influences on psychological well-being, while not showing on learning performance. Fifth, psychological well-being has no significant influence on learning performance. This paper finds its academic significance in its theory-based approach to outplacement service program; research variables and examination are not based on researcher's arbitrary choice. This paper is also practically significant in that it discovered that outplacement service alleviates psychological stress caused by job relocation, and guarantees stable life after retirement.