• 전기의세계
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• v.29 no.12
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• pp.791-797
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• 1980

This paper is concerned with the study of improving the faults of phase control scheme and suggesting a new approach to the control of load circuit with AC source. AC current control can restrict the magnitude of current within the given upper and lower current and make current continuous during every cycle. Also the harmonic contents of current can be greatly reduced using this control scheme. Analog computer and digital computer simulations reveal that the current control scheme is superior to the phase control scheme in controlling the power supply to the load R-L. Experimintal results demonstrate the feasibility and verify the operation of current controlled system.

• Journal of Information Display
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• v.11 no.4
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• pp.154-159
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• 2010

Single-sustainer driving is an AC PDP driving scheme to reduce the circuitry by maintaining the sustain electrode at ground level. To date, however, the research on the discharge characteristics in such driving scheme is insufficient. In this study, the panel performance and discharge characteristics of the single-sustainer driving scheme were observed while varying the address electrode condition. In single-sustainer driving, the address electrode is strongly involved in the sustain discharge when the former is maintained at ground level, and the dependence of the luminous efficacy on the sustain voltage is different from that in the conventional driving scheme. The dependence of the luminous efficacy on the sustain voltage appeared similar, however, to that in the conventional driving scheme when the address electrode was floated in single-sustainer driving. In the investigation of the temporal evolution of the sustain discharge using an IICCD camera, it was found that the sustain discharge in single-sustainer driving with a floating address electrode is similar to that in the conventional driving scheme, and the strong plasma formation region was located in the vicinity of the MgO surface, which seems to be related to the lifetime of a PDP with single-sustainer driving. In the investigation of the operation characteristics, the PDP that was operated with a floated address electrode showed a narrower dynamic operation margin, but a longer lifetime was expected.

• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.141-150
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• 2012

The present study examines an efficient congestion management system compatible with the evolving environment. The key is to build an information model shared and exchanged for marketbased solutions to alleviate congestion. Traditional methods for congestion management can be classified into two categories, i.e., the centralized scheme and the decentralized scheme, depending on the extent to which the independent system operator (ISO) is involved in market participants' (MPs) activities. Although the centralized scheme is more appropriate for providing reliable system operation and relieving congestion in near real-time, the decentralized scheme is preferred for supporting efficient market operation. The minimum set of information between the ISO and MPs for decentralized scheme is identified: i) congestion-based zone, ii) Power Transfer Distribution Factors, and iii) transmission congestion cost. The mathematical modeling of the proposed information is expressed, considering its process of making effective use of information. Numerical analysis is conducted to demonstrate both cost minimization from the MP perspective and the reliability enhancement from the ISO perspective based on the proposed information exchange scheme.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.81-86
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• 1991

The iterative learning operation has been utilized in the temperature Control of a batch reactor. A generic form of feedback-assisted first-order learning control scheme was constructed and then various design and operation modes were derived through convergence and robustness analysis in the frequency domain. The proposed learning control scheme was then implemented on a bench scale batch reactor with the heat of reaction simulated by an electric heater. The results show a great improvement in the performance of control as the number of batch operations progressed.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.34-35
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• 2008

KEPCO conducted a third project in Myanmar regarding system operation and protection scheme. This paper deals with blackout reduction plan, reactive power compensation plan and system restoration procedures in operations parts. Moreover protection system improvement plan and standard protection schemes were suggested.

• The Journal of the Korea Contents Association
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• v.17 no.3
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• pp.370-381
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• 2017

Recently, a complex event processing system has been introduced to quickly and efficiently process real-time events in various applications. Since the existing complex event processing schemes do not consider the similarity and duplication of operators, they perform a lot of computations and consume memory. To solve such problems, this paper proposes an efficient complex event processing scheme considering similar operators and duplication operations. When the same primitive events have similar operations, the proposed scheme combines them into one virtual operator. For duplicated operations, the proposed scheme processes only one of them first, and then processes the others using the results of the already processed operation when the same operation is subsequently performed. It is shown through performance comparison that the proposed scheme outperforms the existing scheme in terms of the whole operation throughput.

• Journal of the Korean Society of Marine Environment & Safety
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• v.9 no.2
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• pp.47-52
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• 2003

This study conducted a basic study to develop ISM Code operation evaluation module, which is part of development of Safety Management System(ISM Code) Implementation supporting module. In particular, the significant of this study is that it established AHP operation evaluation analysis process, the design of questionnaire, and the hierarchical structure of operation evaluation model standard, focusing on the development of ISM Code operation evaluation module. Also, this study has its value in the point that it attempted to apply AHP scheme, which is part of the main decision­making in management science field, to develop operation evaluation module.

• Proceedings of KOSOMES biannual meeting
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• 2003.11a
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• pp.93-97
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• 2003

This study conducted a basic study to develop ISM Code operation evaluation module, which is part of development of Safety Management System(ISM Code) Implementation supporting module. In particular, the significant of this study is that it established AHP operation evaluation analysis process, the design of questionnaire, and the hierarchical structure of operation evaluation model standard, focusing on the development of ISM Code operation evaluation module. Also, this study has its value in the point that it attempted to apply AHP scheme, which is part of the main decision-making in management science field, to develop operation evaluation module.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.10
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• pp.1508-1516
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• 2015

This paper proposes the optimal operation of ESS (Energy Storage System) in the substation of urban railway in an economical point of view. Since the load patterns of urban railway have different characteristics with the general power demand pattern, the characteristics motivate us to develop the optimal operation algorithm for ESS under Korean electricity billing system. We also introduce two different ESS operation strategies for peak load shaving and electricity consumption charge minimization respectively, and formulate each scheme. Historical data from Namgwangju substation are used for economical comparison of the strategies. The results show that the proposed algorithm is the most cost-effective ESS operation scheme among the strategies and reduces around 5 percent of electric charges compared to the charge without ESS operation.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.7
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• pp.149-158
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• 1994

Recently the fuzzy control is widely used as a tool for constructing automatic control systems which can replace the manual operation of large-scale nonlinear plants. In most applications of the fuzzy control however it is hard to meet the requirement of the operation time. In some real-time control the fuzzy control scheme requires too much computing time for fuzzification inference and defuzzification. To reduce the computing time there may be two alternatives the development of a new operation algorithm and the design of high-speed fuzzy hardware. In this paper to solve the problem of reducing the fuzzy operation time we propose a new high-speed fuzzy hardware scheme which has merits of its generality and extensibility. Finally we verify the proposed fuzzy hardware.