• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.254-261
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• 2004

Traditionally, electrical power systems had formed the vertically integrated industry structures based on the economics of scale. However, power systems have been recently reformed to increase their energy efficiency. According to these trends, the Korean power industry underwent partial reorganization and competition in the generation market was initiated in 2001. In competitive electric markets, accurate load data is one of the most important issues to maintaining flexibility in the electric markets as well as reliability in the power systems. In practice, the measuring load data can be uncertain because of mechanical trouble, communication jamming, and other issues. To obtain reliable load data, an efficient evaluation technique to adjust the missing load data is required. This paper analyzes the load pattern of historical real data and then the tuned ARIMA (Autoregressive Integrated Moving Average), PCHIP (Piecewise Cubic Interpolation) and Branch & Bound method are applied to seek the missing parameters. The proposed method is tested under a variety of conditions and also tested against historical measured data from the Korea Energy Management Corporation (KEMCO).

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.727-736
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• 2020

The purpose of this paper is to examine the relationship power distribution among several blockholders (contestability) and firm performance. We use a sample of 646 firms listed in the security markets of Korea from 2005 to 2007. Using different measures of contestability, we verify advance research literature by examining that, when power dispersion among several blockholders (contestability) increases, firm performance is enhanced. The results show that, when the possibility of a controlling coalition being formed among several blocks increases, the corporate value decreases. We also find that this relationship is even more significant in KOSDAQ. However, the smaller the competition of voting rights among blockholders, the higher the corporate performance in KOSPI. The reason for this seems to be that the two markets are different in terms of ownership and governance. This suggests that the effects of contestability among blockholders on firm performance depend on the type of the stock market. The results of this study expand the existing governance literature by analyzing the relationship between contestability among blockholders and firm performance in emerging markets such as Korea. Our findings contribute to policymakers and investors who are interested in the relationship between contestability of control and firm performance in the Korea stock market.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.5
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• pp.78-84
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• 2006

As electric power systems have been moving from a vertically integrated structure to a deregulated environment, calculating reactive power service charges is a new challenging theme for market operators. This paper examines various methods for reactive power management adopted in some deregulated foreign and domestic markets and then proposes a new method to calculate reactive power service charges using a reactive power market. The reactive power market is operated based on bids from the generating sources and is settled on uniform prices by running reactive OPF programs after the day-ahead electricity market. The proposed method takes into account recovering not only the costs of installed capacity but also the lost opportunity costs incurred by reducing active power output to increase reactive power production. A numerical sample study is carried out to illustrate the processes and appropriateness of the proposed method.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.26
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• pp.115-141
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• 2005

This study explores how strategic alliance activities are evolving and the factors that impact on the formation and development of airline alliances. Findings show the initiation of regional and more liberalized bilateral, or open skies, agreements have removed some of the impediments to structural changes in international aviation. Airlines in more liberal markets enter into greater numbers and more integrative forms of alliances. Also, airlines, on average, achieve better results of operation if the market is more liberal. Essentially, there is a positive relationship between the developments of alliances and the liberalization of air transport markets. It has been questioned that the US bilateral open skies agreements provide its carriers more access to the global market and countries that do not enter into such agreements with the US risk a loss of traffic. Consequently, open skies agreements may enable carriers who have the freedom to exercise market power to be dominant in the markets. This suggests that regulatory coordination and liberalization of international aviation reinforce each other and should therefore be pursued simultaneously.

• KIEE International Transactions on Power Engineering
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• v.5A no.4
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• pp.311-321
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• 2005

A competitive generating company (GENCO) could maximize its payoff by optimizing its generation assets. This paper considers the GENCO's arbitrage problem using price-based unit commitment (PBUC). The GENCO could consider arbitrage opportunities in purchases from qualifying facilities (QFs) as well as simultaneous trades with spots markets for energy, ancillary services, emission, and fuel. Given forecasted hourly market prices for each market, the GENCO's generating asset arbitrage problem is formulated as a mixed integer program (MIP) and solved by a branch-and-cut algorithm. A GENCO with 54 thermal and 12 combined-cycle units is considered for analyzing the proposed formulation. The proposed case studies illustrate the significance of simultaneous arbitrage by applying PBUC to multi-commodity markets.

• East Asian Economic Review
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• v.20 no.4
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• pp.519-544
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• 2016

This paper examines quantile dependence and directional predictability between the foreign exchange market and the stock market in Korea. Instead of adopting a multivariate model such as a vector autoregressive model, a multivariate GARCH model or a combination of both models, we apply the cross-quantilogram recently proposed by Han et al. (2016). Considering various quantile ranges, we investigate various spillover effects between two markets. Our findings show that there exists an asymmetric bi-directional spillover between two markets and the interdependence between two markets implies that one market has significant predictive power on the other.

• Journal of Electrical Engineering and Technology
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• v.3 no.2
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• pp.199-206
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• 2008

The introduction of competition in electricity markets emphasizes the importance of sufficient transmission capacities to guarantee effective power transactions. Therefore, for the economic and stable electric power system operation, transmission security constrains should be incorporated into the dispatch scheduling problem. With the intent to solve this problem, we decompose a dispatch scheduling problem into a master problem(MP) and several subproblems(SPs) using Benders decomposition. The MP solves a general optimal power flow(OPF) problem while the SPs inspect the feasibility of OPF solution under respective transmission line contingencies. If a dispatch scheduling solution given by the MP violates transmission security constraints, then additional constraints corresponding to the violations are imposed to the MP. Through this iterative process between the MP and SPs, we derive an optimal dispatch schedule incorporating the post-contingency corrective rescheduling. In addition, we consider interruptible loads as active control variables since the interruptible loads can participate as generators in competitive electricity markets. Numerical examples demonstrate the efficiency of the proposed algorithm.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.567_568
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• 2009

In the past, pumping-storage generator pumped the water from the lower part storage to the upper part storage during the base load periods. And, it generated during the peak load or when other generator was outage. However, pumping-storage generator will operate different ways in the competitive power markets. It will pump during lower price periods and generate at higher price periods. This paper presents economic analysis of pumping-storage generator using price (or SMP) duration curve.

• Journal of Korea Technology Innovation Society
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• v.4 no.3
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• pp.311-322
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• 2001

This study is on the decomposition analysis of the IT export of Korea, Japan, and China (toward US IT market) by using log mean Divisia method. The analysis shows that the increase in the Korea-US IT exports is the result of not only the increase in the US's IT imports but also the increase in the US's IT market shares. The increases in the Japan-US IT export have shown to be the result of the increase of US's IT import but the market shares have been decreased. The increase in the China-US IT export is the result of the changes in the market shares, changes in IT import structure. and the IT import increase. In order to increase exports toward US markets, Korea have to continue increasing the market share of communication equipments, secure competitive power toward US IT markets with the decline of Japanese's market shares, and secure technical superiority over rising competitive power of Chinas IT industry.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.798-800
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• 2005

In competitive electricity markets, the System Operator (SO) coordinates the overall maintenance schedules whenever the collective maintenance schedule reported to SO by Gencos & Transco in the pool does not satisfy the specified operating criteria, such as system reliability or supply adequacy. We propose a two-layer mathematical algorithm amenable to maintenance scheduling problem into master problem and sub-problem. The master problem coordinates the scheduling, and sub-problem, DC optimal power flew, checks the adequacy. The proposed algorithm was demonstrated with a case study.