• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.461-470
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• 2014

This paper presents a probabilistic power flow (PPF) analysis method for distribution network incorporating the randomness and correlation of photovoltaic (PV) generation. Based on the multivariate kernel density estimation theory, the probabilistic model of PV generation is proposed without any assumption of theoretical parametric distribution, which can accurately capture not only the randomness but also the correlation of PV resources at adjacent locations. The PPF method is developed by combining the proposed PV model and Monte Carlo technique to evaluate the influence of the randomness and correlation of PV generation on the performance of distribution networks. The historical power output data of three neighboring PV generators in Oregon, USA, and 34-bus/69-bus radial distribution networks are used to demonstrate the correctness, effectiveness, and application of the proposed PV model and PPF method.

• Journal of People, Plants, and Environment
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• v.21 no.6
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• pp.493-500
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• 2018

The distribution of standing wreaths has reached about 7.1 million per year and the size of the standing wreath market is estimated to be at least 700 billion won. Among them, 20 to 30 percent are estimated to be reused, resulting in damage to flowerfarms' sales of 110 to 160 billion won per year. Due to the unique characteristics of conventional 3-tier standing wreaths in terms of transportation and installation, companies that lack design expertise have monopolized local distribution markets, and the issue of illegally using standing wreaths has been raised. These issues have highlighted the need for developing new designs and establishing a distribution system to expand the consumption of flowers. This study was carried out to identify consumers' perception of reused standing wreaths and the current systems introduced to prevent the distribution of reused standing wreaths such as the real-name standing wreath production system, the authenticity certificate system, and new standing wreaths. The results of a consumer survey showed that consumers' perception of reused standing wreaths has been high and that reused standing wreaths need to be actively regulated to establish fair trade order and protect consumers' rights. Although the effectiveness of the real-name system, the authenticity certificate system, and new standing wreaths was found to be insufficient, the introduction of these systems was essential and necessary for continuous promotion through broadcasting media.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.10
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• pp.1688-1695
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• 2008

Recently, it is common in a distribution system of Korea Electric Power Corporation (KEPCO) to find instances where distribution lines are parallel. A traditional method of an induced voltage calculation is not suitable for parallel distribution lines. For more actual analysis of induced voltage on telecommunication lines in parallel distribution lines, a new calculation method is needed. This paper presents a new calculation method of an induced voltage on telecommunication line using equivalent ${\pi}$ circuits matrix in parallel distribution lines. The advantages of the calculation method are using actual neutral current value and not using screening factor for considering the overhead ground wire and the neutral wire. To verify the effectiveness and the accuracy of the method, various case studies are performed with EMTP(Electro-Magnetic Transients Program).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.753-759
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• 2016

Power automation system to operate power distribution systems can be distinguished by distribution SCADA with remote monitoring and control; and distribution automation system with basic functions such as service restoration to the distribution SCADA; and distribution management system which is operated by various applications in order to enhance distribution system operation performance based on the distribution automation system. In the technological change, a technical boundary of information technology (IT) and operation technology (OT) is being blurred by that new concepts such as interoperability. In addtion, IT/OT convergence has been proposed by the improvement of ICT and power system technology. At the viewpoint, advanced distribution management system (ADMS) to have the new concepts and to increase distribution system operation efficiency through global information and functions from the other systems has been proposed. In order to implement the ADMS, IT and OT have to be employed together on the ADMS; and the concept-based IT/OT convergence concept has been presented. Therefore, this paper introduces ADMS and IT/OT convergence and proposes a design of IT/OT convergence based ADMS system design with configurations and functions.

• Communications for Statistical Applications and Methods
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• v.11 no.3
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• pp.435-446
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• 2004

In this paper we introduced a new score generating function for the rank dispersion function in a multiple linear model. Based on the new score function, we derived the asymptotic relative efficiency, ARE(11, rs), of our score function with respect to the Wilcoxon scores for the generalized F distributions which show very flexible distributions with a variety of shape and tail behaviors. We thoroughly explored the selection of r and s of our new score function that provides improvement over the Wilcoxon scores.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3A
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• pp.227-234
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• 2011

Recently, a high strength concrete of more than 40 MPa has been increasingly used in practice. However, use of the high strength concrete may influence on design parameters, particularly stress distribution. This is very true since the current everyday practice employs equivalent rectangular stress distribution that is derived from normal strength concrete. Subsequently, the stress distribution seems to be reevaluated and then a new distribution with new parameters needs to be suggested for the high strength concrete. For this purpose, linear and multiple regression analyses have been carried out in term of using experimental data for the high strength concrete of 40 to 80 MPa available in literatures. Accordingly, new parameters associated with the stress distribution have been proposed and employed for the design of flexural and compressive members. Comparative design examples indicate that designs with new parameters reduce section dimensions compared to those with the current code parameters for concrete strengths of 40 to 70 MPa. In particular, for compressive members, design with new parameters exhibit conservative compressive force compared to those with the current code parameters.

• Journal of Sport and Applied Science
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• v.5 no.2
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• pp.23-29
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• 2021

Purpose: The purpose of the study is to review the current states of new sports imported from foreign countries and to discuss strategic insights for promoting new sports which has been invented in Korea. Research design, data, and methodology: This study employed the qualitative approach, in which reviewed a related literature. First, the study selected flying disc, sports stacking, and T-ball as sample cases. This is because these new sports were recognized the prominent sports frequently played in physical education classes in Korea. Second, the study reviewed prior studies in the field of distribution and marketing in order to determine the criteria of analysis and variables that frequently examined in distribution and marketing studies. Finally, the study confirmed such terminologies as research variables including new sport name, organization name, background of the invented sports, distributional channel, promotional activities and so forth. To collect data, the study search literature via academic search engine including DBpia, KISS, RISS, ScienceDirect, SAGE Journals, SpringerLink, and Taylor & Francis. Results: It was found that all of the imported new sports organized association and its nationwide branches to deliver their sprots to local schools and recreational markets. second, they targeted schools and sought to broaden their markets to recreational communities. Conclusions: In order to promote new sport invented in Korea, associations need to be systematically organized and mission should be clearly stated. In addition, creative methods for promotion need to be developed. Future directions were discussed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.229-232
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• 2004

This paper is about the new Distribution System of the electric customers. The Power loss in the Distribution System is disregarded and rarely managed so far. But, economically, this loss is not small quantity to Ignore. So, in this paper, we suggest that the new Distribution System of the electric customer by simply changing the locations of Power Transformer and other power facilities which is located inside of the customer. And we also show that the Power loss is decreased with this systematic changing by approximated calculation.

• Communications for Statistical Applications and Methods
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• v.26 no.4
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• pp.385-410
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• 2019

This paper proposes a new class of distribution using the concept of exponentiated of distribution function that provides a more flexible model to the baseline model. It also proposes a new lifetime distribution with different types of hazard rates such as decreasing, increasing and bathtub. After studying some basic statistical properties and parameter estimation procedure in case of complete sample observation, we have studied point and interval estimation procedures in presence of type-II censored samples under a classical as well as Bayesian paradigm. In the Bayesian paradigm, we considered a Gibbs sampler under Metropolis-Hasting for estimation under two different loss functions. After simulation studies, three different real datasets having various nature are considered for showing the suitability of the proposed model.

• The Korean Journal of Applied Statistics
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• v.22 no.1
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• pp.205-220
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• 2009

For modeling skewed semicircular data, we derive new family of the exponential distributions. We extend it to the l-axial exponential distribution by a transformation for modeling any arc of arbitrary length. It is straightforward to generate samples from the f-axial exponential distribution. Asymptotic result reveals two things. The first is that linear exponential distribution can be used to approximate the l-axial exponential distribution. The second is that the l-axial exponential distribution has the asymptotic memoryless property though it doesn't have strict memoryless property. Some trigonometric moments are also derived in closed forms. Maximum likelihood estimation is adopted to estimate model parameters. Some hypotheses tests and confidence intervals are also developed. The Kolmogorov-Smirnov test is adopted for goodness of fit test of the l-axial exponential distribution. We finally obtain a bivariate version of two kinds of the l-axial exponential distributions.