• KIEE International Transactions on Power Engineering
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• v.4A no.3
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• pp.122-128
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• 2004

With the advent of distributed generation, power systems are fundamentally impacted in regards to stability and power quality. Distributed generation has a positive impact on system restoration following a fault, higher reliability, and mitigation of effect due to voltage sag. However, distributed generation also has a negative impact on decrease of reliability such as changes of protective device setting and mal-operation. Because bulk power systems consist of various sources and loads, it becomes complicated to analyze a power system with distributed generation. The types of distributed generation are usually classified by both rotating machinery and the inverter-based system. In this paper, distributed generation is designed by rotating machinery, and the distributed system having a model of the distributed generation is simulated using EMTP. In addition, this paper presents the simulation results according to the types of distributed generation.

• Journal of Families and Better Life
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• v.14 no.2
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• pp.97-110
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• 1996

The purpose of this study was to compare the caregiver burden and rewards in new generation and middle-aged couples. Data were collected from 207 new generation couples and 196 middle-aged couples who had either of older parents and lived in Seoul. Major findings are as fallows; 1. The burden were constituted with restriction of privacy physical burden strain psychological burden economic cost and guilt. The rewards were constituted with recognition pride maturity improving relationship and assistance of household and childcare. 2. The caregiver burden of new generation and middle-aged wives were hgiher than husbands. Hwever the caregiver rewards of new generation and middle-aged husbands were higher than wives. 3. The caregiver burden of middle-aged husbands were higher than new generation husbands bur there was no significant difference between new generation and middle-aged wives. 4. The caregiver rewards of middle-aged wives were higher than new generation wives but there was no significant difference between new generation and middle-aged husbands.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.115-116
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• 2014

This study investigated power generation of photovoltaic equipment at detached houses. The study estimated monthly mean generation according to maintenance conditions that included module cleaning, inspection into generation, cleaning of module and photovoltaic generation. At analysis upon generation, households with periodical module cleaning and inspection into generation, clean module and good generation conditions had high generation. 20-years of PV equipment life varied much depending upon maintenance conditions. Users should keep module clean and inspect generation regularly and put PV equipment at the place with good solar radiation.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.201-206
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• 2004

With the advent of distributed generation, power systems in general are impacted in regards to stability and power quality. Distributed generation has positive impacts on system restoration following a fault, higher reliability, and mitigation of effect due to voltage sag. However, distributed generation also has negative impacts on the decrease of reliability such as changes of protective device setting and mal-operation. Because bulk power systems consist of various sources and loads, it is complicated to analyze power systems that have distributed generation. The types of distributed generation usually are classified as the rotating machinery system and the inverter-based system. In this paper, distributed generation is designed as a synchronous generator, and the distribution system with its distributed generation model is simulated using EMTP. In addition, this paper shows the simulation results according to the types of distributed generation

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.8
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• pp.1349-1355
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• 2008

The paper shows the analysis of operating conflict of OCGR trip events and metering errors in the photovoltaic generation, wind generation distributed generation customers with no defect of the distributed generation facilities, which are connected to 22.9kV distribution lines. To analyze problems with metering errors and OCGR fault event, a power quality analyzer and PSIM program were used to test the field and to simulate in Sun-Cheon photovoltaic generation and Seo-Cheon photovoltaic generation customers. With the trial distribution line, the result of analysis was verified to prove with the same situation of the actual field. This paper suggests short term and long term countermeasures of OCGR fault events, analysis of over and shortage of metering errors in distributed generation customers.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.11
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• pp.2175-2184
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• 2009

This paper describes operational analysis results of the DC micro-grid using detailed model of distributed generation. Detailed model of wind power generation, photo-voltaic generation, fuel-cell generation was implemented with the user-defined model of PSCAD/EMTDC software that is coded with C-language. The operation analysis was carried out using PSCAD/EMTDC software, in which the power circuit is implemented by built-in model and the controller is modelled by user-defined model that is also coded with C-language. Various simulation results confirm that the DC micro-grid can operate without any problem in both the interconnected mode and the islanded mode. The operation analysis result confirms that the DC micro-grid make it feasible to provide power to the load stably. And it can be utilize to develop the actual system design and building.

• Journal of Magnetics
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• v.12 no.2
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• pp.53-58
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• 2007

Theory of the generation linewidth of a current-driven spin-torque magnetic nano-oscillator in the presence of thermal fluctuations has been developed and a simple analytical formula for the generation linewidth in the supercritical regime of generation has been derived. It is shown that the strong dependence of the oscillator frequency on the precession power leads to substantial broadening of the generation linewidth of a spin-torque oscillator compared to the case of a linear oscillator, i.e. an oscillator with power-independent generation frequency. The relation between the nonlinearity-induced broadening of the generation linewidth and the nonlinearity-induced increase of the phase-locking band of a spin-torque oscillator to an external microwave signal has been revealed. The derived expression for the generation linewidth predicts a linewidth minimum when the nano-contact is magnetized at a certain angle to its plane, at which the nonlinear frequency shift vanishes. This result is in good agreement with recent experiments.

• Journal of the Korea Fashion and Costume Design Association
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• v.22 no.3
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• pp.49-61
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• 2020

This study analyzed the social media accounts and performed a Big Data analysis of Z-generation fashion using Textom Text Mining Techniques program and Ucinet Big Data analysis program. The research results are as follows: First, as a result of keyword analysis on 67.646 Z-generation fashion social media posts over the last 5 years, 220,211 keywords were extracted. Among them, 67 major keywords were selected based on the frequency of co-occurrence being greater than more than 250 times. As the top keywords appearing over 1000 times, were the most influential as the number of nodes connected to 'Z generation' (29595 times) are overwhelmingly, and was followed by 'millennials'(18536 times), 'fashion'(17836 times), and 'generation'(13055 times), 'brand'(8325 times) and 'trend'(7310 times) Second, as a result of the analysis of Network Degree Centrality between the key keywords for the Z-generation, the number of nodes connected to the "Z-generation" (29595 times) is overwhelmingly large. Next, many 'millennial'(18536 times), 'fashion'(17836 times), 'generation'(13055 times), 'brand'(8325 times), 'trend'(7310 times), etc. appear. These texts are considered to be important factors in exploring the reaction of social media to the Z-generation. Third, through the analysis of CONCOR, text with the structural equivalence between major keywords for Gen Z fashion was rearranged and clustered. In addition, four clusters were derived by grouping through network semantic network visualization. Group 1 is 54 texts, 'Diverse Characteristics of Z-Generation Fashion Consumers', Group 2 is 7 Texts, 'Z-Generation's teenagers Fashion Powers', Group 3 is 8 Texts, 'Z-Generation's Celebrity Fashions' Interest and Fashion', Group 4 named 'Gucci', the most popular luxury fashion of the Z-generation as one text.

• Proceedings of the KIEE Conference
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• 2007.11c
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• pp.170-174
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• 2007

Recently, a fuel cell is remarkable for new generation system. The fuel cell generation system converts the chemical energy of a fuel directly into electrical energy. The fuel cell generation is characterized by low voltage and high current. For connecting to utility, it needs both a step up converter and an inverter. The step up converter makes DC link and the inverter changes DC to AC. In this paper full bridge converter and the single phase inverter are designed and installed for fuel cell. Simulation and experiment verify that fuel cell generation system could be applied for the distributed generation.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.819-822
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• 1998

The high complexity of digital circuits has changed the digital circuits design mehtods from schemeatic-based to hardware description languages like VHDL, verilog that make hardware faults become more hard to detect. Thus test generation to detect hardware defects is very important part of the design. But most of the test generation methods are gate-level based. In this paper new high-level test generation method to detect stuck-at-faults on gate level is described. This test generation method is independent of synthesis results and reduce the time and efforts for test generation.