• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.12
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• pp.210-216
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• 2009

Distributed Generation (DG) is predicted to play a important role in electric power system in the near future. insertion of DG system into existing distribution network has great impact on real-time system operation and planning. It is widely accepted that micro turbine generation (MTG) systems are currently attracting lot of attention to meet customers need in the distributed power generation market. In order to investigate the performance of MT generation systems, their efficient modeling is required. This paper presents the modeling and simulation of a MT generation system suitable for stand-alone operation. The system comprises of a permanent magnet synchronous generator driven by a MT. A brief description of the overall system is given, and mathematical models for the MT and permanent magnet synchronous generator are presented. Also, the use of power electronics in conditioning the power output of the generating system is demonstrated. Simulation studies with MATLAB/Simulink have been carried out in stand-alone operation mode of a DG system.

• Journal of Power Electronics
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• v.11 no.3
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• pp.350-359
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• 2011

This paper describes the operational analysis results of a DC micro-grid using a detailed model of distributed generation. A detailed model of wind power generation, photo-voltaic generation and fuel cell generation was implemented with an userdefined model created with PSCAD/EMTDC software and coded in C-language. The operational analysis was carried out using PSCAD/EMTDC software, in which the power circuit is implemented by a built-in model and the controller is modeled by an user-defined model that is also coded in C-language. Various simulation results confirm that a DC micro-grid can operate without any problems in both the grid-tied mode and in the islanded mode. The operational analysis results confirm that the DC micro-grid makes it feasible to provide power to the load stably. It can also be utilized to develop an actual system design.

• Journal of Fashion Business
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• v.9 no.2
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• pp.84-99
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• 2005

This is a study about the fashion value of generation y, those who were junior and high school students between 1990 and 2004 in the U. S. This study was mainly based on the street culture and fashion of American teenagers the author observed in New York from 1997 to 2004, and referred to articles carried by major American journals, the result d Census 2000, statistical data reported by well-credited American research institutions. To overview the values generation y applies to their fashion, this study picked 8 principal values generation y pursues in their fashion and put them in four sets of contrasting pairs, as in conformity vs. Individuality, authenticity vs. trendiness, comfort vs. sexuality, rebelliousness vs. conservativeness. The results are as follow. First, when it comes to fashion, generation y desires to be noticed by others, but is afraid d being too different from their peers. Second, generation y stresses authenticity in their fashion. But, they are very much interested in mass fashion trend as well, and the pursuit of authenticity itself can be just a trend. Third, generation y wants their fashion to be "not only sexy and feminine, but also sporty and athletic" all at the same time. Forth, generation y uses fashion to visualize their rebelliousness. But their rebellious spirit is diluting amid the rise of neo-conservatism. As a conclusion, generation y's fashion has changed the way that compromises contrasting values, and in the process, were created unique new styles.

• Journal of the Korean Solar Energy Society
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• v.26 no.2
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• pp.53-59
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• 2006

The number of wind generation installations are growing substantially in Jeju, Korea. Many of these installations are significant in size and directly connected to the distribution system. Utility grid interconnection standards for interconnecting non-utility distributed generation systems are essential to both power system company and generation company. These interconnection standards are important to utilities, customers, wind generation manufactures and nation. In this paper, it is investigated the voltage quality and the suitability of Jeju-Hangwon wind power generation farm by network interconnection technology standard.

• Korean Medical Education Review
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• v.14 no.2
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• pp.59-63
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• 2012

Current medical students are a distinct new generation who can be distinguished from the previous generation. Therefore, a clear understanding of their characteristics is vital in developing an appropriate educational program for them. The purpose of this article is to explore the characteristics of the current generation of high achieving medical students. Notable characteristics that define this generation include the following: they feel they are special, and they are sheltered, confident, highly optimistic, pressured, conventional, and have a strong desire to achieve. They are the digital generation, who can obtain information through various forms of technology. Furthermore, they are high achieving students in highly competitive educational environments. It has been suggested that various teaching methods be used in the medical school classroom. Using digital methods could be crucial in providing high-quality medical education. Educators should pay more attention to students' psychosocial development and help them to effectively cope with their academic stress.

• Fashion & Textile Research Journal
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• v.14 no.5
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• pp.758-765
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• 2012

As the 21st century is the post-digital era, a mix of the hard digital and the soft analog realm, the school uniform designs for the post-digital generation need to be changed within this paradigm shift. Thus, this study is conducted with the purpose of developing the school uniform design that reflects aesthetic value and sensitivity of the post-digital generation. The definition and background of the post-digital generation is reviewed and the values of this generation are drawn based on the theoretical research. Also, through the survey of 205 high school girls in Seoul, the purchase, wear & fit, and suggestions for improvement of present school uniforms are investigated. Based on the studies above, the guidelines for designing school uniforms for the post-digital generation are established and the products are developed.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.183.1-183.1
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• 2010

Recently, the increased interest in environmental issues has led to extensive research for development of green energy generation systems. However, only one type of generation system may not be sufficient for stand-alone mode because it cannot cope with the irregularity of weather condition. A hybrid generation system is able to make up for the weakness of each system. In this paper, a stand-alone hybrid wind/PV system is developed that can guarantee the stable energy supply. The system is suitable for power supply under 50W, and a vertical savonius type of blade was designed and applied for the wind generation system.

• The Journal of Society for e-Business Studies
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• v.4 no.3
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• pp.213-234
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• 1999

Currently, various international standard organizations, academic institutes, and private organizations are making efforts to improve and expand the traditional EDI. The next generation EDI has potential to impact on the existing and planned EDI systems. Major objective of this study is to systematically analyze and compare various next generation EDI technologies. In order to accomplish the research objective, this paper presented the following three issues. First, overall development trend and types of the next generation EDI were analyzed. Secondly, basic concepts of a few important next generation EDI technologies were presented. Lastly, models to be used to analyze the various next generation EDI technologies were proposed and results of the analyses peformed based on the proposed models were presented.

• Analytical Science and Technology
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• v.25 no.6
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• pp.339-344
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• 2012

In this research, hydride generation in HPLC-ICPMS for the selenium speciation was investigated. Chemical and photochemical vapor generation techniques were compared for the effective generation of selenium vapour. $HBr/KBrO_3$ was used for the chemical reduction and a UV lamp was used for the photochemical reduction. It was found out that the photochemical reduction was more effective than the chemical reduction in all of selenium species studied. The optimum conditions for the generation of vapour are 0.4% KI, 2.5% $NaBH_4$, and 1.0 M HCl. The enhancement factor using a photochemical hydride generation was from 6.3 to 16.7 times for inorganic and organic selenium species.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.335-338
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• 2004

In this paper, we present a perspective of the next generation mobile communication services and its characteristics. As a preliminary research work on the next generation mobile communications and services, we exploit the next generation mobile services [1]. We define the next generation mobile services as strata of services consisting of three different service levels, the service areas, the service functionalities, and the service technologies. We derive these service levels by means of the scenario based analysis. Finally, we propose a conceptual network architecture that can support the next generation mobile services by placing network functions and service elements within the network.