• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.9
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• pp.78-83
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• 2006

A new measure, the distributed generation impact factor (DGIF), is used for evaluating the impact of newly introduced distributed generators on a networked distribution or a transmission system. Distribution systems are normally operated in a radial structure. But the introduction of distributed generation needs load flow calculation to analyze the networked system. In the developed framework, the potential share of every generation bus in each line flow of a networked system can be directly evaluated. The developed index does not require the solution of power flow equations to evaluate the effect of the distributed generation. The main advantage of the developed method lies in its capability of considering simultaneous outputs of multiple generation sites.

• 연구논문집
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• s.31
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• pp.45-51
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• 2001

One of emerging technologies under development in the advanced countries is considered as RDF(Refuse Derived Fuel) power generation, which could meet both the requirement of an alternative energy resource utilization and $CO_2$ reduction. This paper deals with the effect to the thermal effiency and CO2 reduction of RDF firing power generation. The statistical data of domestic MSW generation in last year in small and medium cities for evaluating the merits of the RDF power generation were used. The analysis for RDF power generation compared to the existing incinerator w/o(or w/) power generation shows around 20.6%(10.0%) up in the total thermal efficiency and 57.0%(31.4%) up in the $CO_2$ reduction respectively.

• Journal of Information Processing Systems
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• v.19 no.1
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• pp.1-16
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• 2023

Synthetic data generation is generally used in performance evaluation and function tests in data-intensive applications, as well as in various areas of data analytics, such as privacy-preserving data publishing (PPDP) and statistical disclosure limit/control. A significant amount of research has been conducted on tools and languages for data generation. However, existing tools and languages have been developed for specific purposes and are unsuitable for other domains. In this article, we propose a regular expression-based data generation language (DGL) for flexible big data generation. To achieve a general-purpose and powerful DGL, we enhanced the standard regular expressions to support the data domain, type/format inference, sequence and random generation, probability distributions, and resource reference. To efficiently implement the proposed language, we propose caching techniques for both the intermediate and database queries. We evaluated the proposed improvement experimentally.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.809-812
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• 2007

Automatic generation method of structural analysis model data for a truss bridge is presented through 3-D bridge information modeling based on Industry Foundation Classes(IFC). The mapping schema is proposed between a steel bridge information model based on STEP and a truss bridge information model based on the IFC. The geometry information from mapping is presented by IFC model, and SAP 2000 that can import the IFC file performs the structural analysis. Numerical analysis for a truss bridge is performed in this paper.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.2
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• pp.69-78
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• 2003

This paper presents a voltage analysis method of distribution systems interconnected with DG(Distributed Generation). Nowadays, small scale DG becomes to be introduced into power distribution systems. But in that case, it is difficult to properly maintain the terminal voltage of low voltage customers by using only ULTC(Under Load Tap Changer). This paper presents a voltage analysis method of distribution systems with DC for proper voltage regulation of power distribution systems with ULTC. In order to develop the voltage analysis method, distribution system modeling method and advanced loadflow method are proposed. Proposed method has been applied to a 22.9 kV practical power distribution systems.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.539-541
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• 2009

A severely cold weather condition of King Sejong Station, Antarctica becomes a very severe condition for an installation/operation of wind generation system. When the existing wind generation system works, it may cause a damage and destruction of wind generation system and can bring about big problems in terms of the power quality. Accordingly, it is essential to obtain technologies for the installation and operation of small wind generation system for the polar region's wind generation, and to assess and demonstrate the performance in the severely-cold environment and the polar wind generation system's development, supplementation, alteration. Also, as the available power of King Sejong Station, Antarctica, the diesel generator has been mainly used, and the wind generator has been used in the hybrid form. Wind generation and diesel generation has the different load following control each other. In the wind generation, the generated power very rapidly changes according to the change of the velocity of the wind. On the other hand, the diesel generation shows very gentle change in the velocity of output. Therefore, the study is intended to analyze the 10kw small wind generator-diesel generator's power quality of King Sejong Station, Antarctica, which is the hybrid system installation area.

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.187-196
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• 2021

This study uses data from the 11th year(2016) to the 15th year(2020) of the Korea Welfare Panel(KOWEPS) for the five years that the survey was completed to predict the life satisfaction of each individual by generation, centered on single-person households. This is a longitudinal analysis using a latent growth model. The generational division was based on the turning point of a major event experienced by the cohort that brought about a decisive change in the socialization process, historical event, and technological development as factors. The analysis data used in this study were of 27,447 persons in the 15th year of the Korea Welfare Panel(2020), 2,778 persons who were single-person households even in the first year from the last 5 years, and 1,448 persons who were single-person households continuously for 5 years. Excluding those born in 1922 to 1944(843 persons), 605 persons born between 1945 and 1996 were included. As a result of the study, Generation Y(millennials) than Generation X(new generation) and Generation X generation than Baby Boomers showed higher overall life satisfaction. Since overall life satisfaction by generation does not have an effect on the rate of change, it was found that this difference remains the same for all generations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.313-322
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• 2019

This study poses a question on whether the Jangmadang Generation, which has been the focus of the sociological interest, can form an actual generation by transcending the social classes, status of students, ethnicity, and gender, etc. Therefore, in this study, the author compared the consciousness of the Jangmadang Generation in terms of politics, education, society, compliance with law, and education with their preceding generations. The data used in this study were gathered from the North Korean defectors who defected within the past five years over the period from November to December 2016. A total of 200 questionnaires were used for data analysis, which was conducted using SPSS 20.0, in order to show differences between groups and perform frequency analysis. The analysis results showed that the consciousness of the Jangmadang Generation in politics, society, compliance, and education was lower, while the economic consciousness was significantly higher compared to earlier generations. As their objective generational status, the Jangmadang Generation had experienced the 'March of Ordeal' and 'Collapse of Public Education' while they were still teenagers. Such a difference in their generational status influenced the formation of different consciousness as a generation compared to the earlier generations. Compared to the earlier generations who received 'proper public education,' the Jangmadang Generation, who did not receive 'decent public education' shows a generally lower level of consciousness compared to the earlier generations. As such, the Jangmadang Generation has the potential to form a separate generation with a different generation consciousness from that of earlier generations.

• Journal of computational fluids engineering
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• v.20 no.2
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• pp.23-36
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• 2015

The $2^{nd}$ generation ice accretion analysis program has been developed and validated for various icing conditions. The essential feature of the $2^{nd}$ generation code lies in its capability of handling general 3-D geometry and improved accuracy. The entire velocity fields are obtained based on Navier-Stokes equations in order to take the massively separated flow field into account. Unlike $1^{st}$ generation code, the droplet trajectories are calculated using Eulerian approach, which is adopted to yield appropriate collection efficiency even in the shadow region. For improved thermodynamic analysis on the surfaces, water film model and modified Messinger model are newly included in the present analysis. The ice shape for a given time step is obtained by considering the exact amount of ice accreted on the surface. Each module of the icing analysis code has been seamlessly integrated on the OpenFOAM platform. The developed code was validated against available experimental data for 2D airfoils and 3D DLR-F4. Due to the lack of experimental data, the computed results of DLR-F4 were compared with those obtained from FENSAP-ICE, which is state-of-the-art 3D icing analysis code. It was clearly shown that the present code produces comparable results to those of FENSAP-ICE, in terms of prediction accuracy and the capability of handling general 3-D geometries.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.7-12
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• 2008

This study aims to extract the factors which constitute use tendency on digital product, and to devide korean generation. We surveyed to digital product users who are 15 through 49 years old, executed factor analysis, cluster analysis, and so on, The results of factor analysis, we selected 11 factors, named as interest, entertainment, simplicity, anxiety of mal-operation, practicality, personality, consistency, multi-functionality, learning style of how-to-use, responsibility of disorder, and lending degree. The results of cluster analysis, we classified subjects into following three types: positive acceptor, passive follower, and conservative indifference. And, we executed frequency analysis iteratively. We devide korean digital product users to 4 generations -1727G, 2834G, 3538G, 3949G- by means of synthesizing the results. It can be said that generation is strong factor effect to use tendency, but the other factors like sex, occupation, school career, income become weak factor or not matters. Finally, we considered the reason, 3538G takes a crossing point role through comparison the generation division with cohort research on product use experience.