• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.233-235
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• 2004

This paper studies protective coordination of utility interconnected multiple distirbuted generations(DG). The study of protective coordination interconnected DG has been conducted. A protective coordination of utility disturbed by reverse current of DG. Therefore, A protetive device is not operate when reverse current flows. In this paper, we use phase difference between V and I. Also, we studied protective coordination algorithm of utility interconnected multiple DG.

• Journal of the Korean Home Economics Association
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• v.29 no.1
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• pp.125-137
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• 1991

This study aims to offer basic data for development of the three generations sharing house plan, through finding out the relationship between family characteristics and the housing needs of the middle aged living in the middle and small cities. The 1029 questionnaires were used for this study, and data were analysed by canonical correlation analysis, factor analysis and multiple regression. The results are as follows. Their family characteristics influence housing needs for the three generations sharing house. Especially groups of female, neuclear family, family of higher S.E.S., less number of children. family living in the apartment houses and owner occupied house prefer more privacy between generations in the three generations sharing house.

• Journal of Families and Better Life
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• v.7 no.1
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• pp.59-78
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• 1989

The purpose of this study is to clarify the value orientation about family life between the older generations and college student. For this purpose, questionnaire were distributed to the older generations and college students in Seoul. Among them 920 data were obtained To obtain the family value scale, item analysis through pearson's correlation and factor analysis were used in pretest, frequency distribution, percentile, mean , t-test , and step-wise multiple were used for data analysis. The results are summarized as follows. 1) Male college students show traditional tendency and female college students show modern tendency especially sex-role attitude, ancestor worship attitude, patriarchy attitude. 2) Male and female of the older generations how traditional tendency. 3) The older generations show traditional tendency, college students show modern tendency, especially sex-role attitude and kinship attitude. 4) Male adults and male college students show traditional tendency. 5) Female adults show traditional tendency , female college students show modern tendency. In female, generation gap is more serious than males. 6) the most influencial socio-demographic variables on family value consciousness of the older generations are the religion and education, In case of college students, sex, major, religion, family income grown-up area effect on their value consciousness about family life, Based on the above findings , we should develop school education and many social programs to reduce the generation gap.

• Korean Journal of Health Education and Promotion
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• v.22 no.2
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• pp.33-46
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• 2005

Objectives: The purpose of this study is to identify the influential factors on health behavior of the middle and elderly generations in a rural community. Methods: The subjects of this study were 495 people. The data were analyzed using descriptive statistics, T-test, ANOVA, Pearson's correlation coefficient and multiple regression analysis. Results: 1. The differences of health behavior by sample characteristics were found to have significance of age, marital status, residence status, education level, and occupation. 2. The level of health behavior was related positively to the level of social support and self-efficacy. The level of health behavior was related negatively to the level of anxiety and depression. 3. The multiple regression analysis revealed that the most powerful predictor of health behavior was 'social support,' followed by anxiety and self-efficacy. A combination of social support (42.1%), anxiety (3.0%) and self-efficacy (0.8%) accounted for 45.9% of the variance in health behavior in the middle and elderly subjects. Conclusions:. The findings of this study could be effectively used to develop a practical management strategy to help promote health and health behavior of the middle and elderly people living in rural communities. In addition, the one idea to be emphasized should be the development of efficient health education programs that can have a favorable effect on the middle and elderly generations' physical, psychological and social health.

• Journal of Family Resource Management and Policy Review
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• v.17 no.1
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• pp.199-219
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• 2013

The purpose of the study was to investigate the effects of money transfer between generations on preparation behaviors for retirement, separated into assets and saving for retirement. The survey was conducted by targeting 422 married people across the nation. The factor of money transfer between generations was defined as the inheritance and gift variable. The data were analyzed using SPSS 20. Correlation, analysis of variance (ANOVA), and multiple regressions were utilized. The results indicated that preparation behaviors for retirement are affected by the economic independence of parents, inheritance, expenses for children's education, and marriage. Retirement assets were significantly affected by inheritance, the economic independence of parents, educational expenses for children, financial assets, and amount of debt, while the significant factors related to retirement savings were interests on retirement, income, wedding expenses for children, economic independence of parents, and educational expenses for children. It was concluded that the financial preparation for retirement ought to be expanded from one household's finances to finances between generations.

• Journal of Electrical Engineering and Technology
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• v.1 no.2
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• pp.192-199
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• 2006

This paper presents an improved anti-islanding algorithm for utility interconnection of multiple distributed fuel cell powered generations (DFPGs). A cross-correlation method is proposed and implemented in conjunction with the anti-islanding algorithm developed in the previous work [I]. While the power control algorithm continuously perturbs $({\pm}5%)$ the reactive power supplied by the DFPG, the proposed algorithm calculates the cross-correlation index of a rate of change of the frequency deviation with respect to $({\pm}5%)$ the reactive power to confirm islanding. If this index is above 50%, the algorithm further initiates $({\pm}10%)$ the reactive power perturbation and continues to calculate the correlation index. If the index exceeds 80%, the occurrence of islanding can be confirmed. The proposed method is robust and capable of detecting the occurrence of islanding in the presence of several DFPGs, which are independently operating. Viability of the cross-correlation method is verified by the simulation. Experimental results are presented to support the findings of the proposed method.

• Korean Journal of Social Welfare Studies
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• v.44 no.2
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• pp.437-463
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• 2013

As polarization and class reproduction between generations are considered to be serious problems in Korean society, increasing number of assortative mating, which means marrying between homogeneous family background, income class, and educational background, is on the spotlight socially. Some worry that the increase of assortative mating can reinforce closure of social mobility so it deepens inequality and limits class mobility between generations. This research analyzes the effects of accomplishment characteristics of husbands and wives and ascriptive characteristics of parents which consist the concept of assortative mating, on income, consumption, and assets those represent economic status of a family. The purpose of this research is to suggest empirical understanding on the role of assortative mating that affect on inequality within generations and income mobility between generations in Korean society. In the result of multiple regression analysis on the effect of assortative mating on income, consumption, and assets, high educational background was the factor that increase income and consumption level as accomplishment characteristics of assortative mating. As ascriptive characteristics of assortative mating, educational homogeneous of fathers was the factor that increased asset level. While accomplishment characteristics affect income and consumption, ascriptive characteristics of homogeneous had significant effect on assets. Thus, it was found that transfer between generations had effects around asset rather than income. In particular, ascriptive characteristics in young husbands and wives aged 20s or 30s had significant effect only on the assets.

• Journal of Power Electronics
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• v.18 no.5
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• pp.1479-1488
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• 2018

Power packet (PP) distribution system distributes power to different loads that share the same distribution cable in a packetized form. When compared with conventional power systems, a PP distribution system (PPDS) can reduce standby power, eliminate Point-of-Load (PoL) power conversion, and intelligently control the load demand from the source side. Due to the absence of PoL conversion, when multiple power sources at different voltage levels and conditioning requirements jointly send power to various loads at different voltage ratings, the generated voltage has an irregular shape. A large filter at each of the load sides is required to reduce such a large voltage ripple. In this paper, a single-inductor, multiple-input-single-output converter structure based multiple-energy-source mixer is proposed. It combines PP generation, maximum power point tracking (MPPT) of renewable energy sources (RESs) and filtering at the source side. To demonstrate the possible renewable energy integration, a PV panel is used as a power source together with other constant voltage sources. The PV power is approximately tracked using the constant voltage method and it is used for each of the PP generations. The proposed PP distribution system is experimentally verified and it is shown that a conventional PI controller is sufficient for stable system operation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.6
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• pp.533-538
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• 2004

Recently, it is increasing the concern of distributed generations(DGs) that installed small power at a site near by the customer. In deregulation environment, not only distributed generation operation but also state estimation is the key function in distribution systems. This paper process to calculate the impact of distributed generation on a distribution feeder. WLAV state estimation is performed the distribution systems with DGs and bad data test including single, multiple, interacting. Simulations with test cases are performed and the results are presented, using IEEE 34 bus radial distribution systems

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.11
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• pp.1910-1920
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• 2007

This paper deals with the optimal evaluation algorithms for voltage regulation in the case where new dispersed generations(DG) are operated in distribution systems. It is very difficult and complicated to handle the interconnection issues for proper voltage managements, because professional skills and enormous amounts of data for the evaluations are required. The typical evaluation algorithms mainly depending on human ability and quality of data acquired, inevitably cause the different results for the same issue, so unfair and subjective evaluations are unavoidable. In order to overcome these problems, the paper proposes reasonable and general algorithms based on the standard model system and proper criterion, which offers the fair and objective evaluations in any case. The proposed algorithms are divided by two main themes. One is an optimal algorithm for the voltage control of multiple voltage regulators in order to deliver suitable voltage to as many customers as possible, and the other is a proper evaluation algorithm for the voltage management at normal and emergency conditions. The results from a case study show that the proposed methods can be a practical tool for the voltage management in distribution systems including dispersed sources.