• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1725-1727
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• 2005

Korea Water Resource Corporation is planning the active application on the New-Renewable energy enterprise at Si-Wha region which is located in Kyonggi-Do, builded up as the national policy enterprise and also currently carrying out a tidal electric power station construction. This research is considered of geography circumstance of the region. We are to analyze a wind power resources application feasibility in the side of economical efficiency and see simultaneously application of the wind power system also.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.522-524
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• 2018

A New Direct AC LED Driver has been proposed for wide output power range and precise constant current regulation using an advanced auto commutation topology. The conventional shunt regulation method provides a stepped input current shape by fixed regulation references in the linear regulator of the each channel, which results in poor current regulation and high THD. The conventional method needs to assign a linear regulator in each LED channel so that the number of linear regulator increases when extending the number of channels especially at high power application. The proposed regulation method can drive multiple switches to regulate each LED channel current by a single amplifier with sinusoidal reference so that large number of LED channel can be simply extended with less BOM cost and low THD is obtained with the accurate current regulation thanks to the sinusoidal input current control in the closed loop control. To confirm the validity of the proposed circuit, theoretical analysis and experimental results from a 20-W LED driver prototype are presented.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1124-1136
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• 2017

Direct Power Control technique has become popular in the grid connected Voltage Source Converter (VSC) applications due to its simplicity, direct voltage vector selection and improved dynamic performance. In this paper, a direct method to determine the effect of voltage vector on the instantaneous active and reactive power variations is developed. An alternative Look Up Table is proposed which minimizes the commutations in the converter and results in minimum reactive power variation. The application of suggested table is established for Shunt Active Power Filter (SAPF) application. The Predictive Direct Power Control method, which minimizes apparent power variation, is further investigated to reduce commutations in converters. Both the methods are validated using 2 kVA laboratory prototype of Shunt Active Power Filters (SAPF).

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.97.2-97.2
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• 2008

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.224.2-224.2
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• 2008

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.225.1-225.1
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• 2008

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.221-226
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• 2004

As power systems grow more complex and power demands increase, the fault current tends to gradually increase. In the near future, the fault current will exceed a circuit breaker rating for some substations, which is an especially important issue in the Seoul metropolitan area because of its highly meshed configuration. Currently, the Korean power system is regulated by changing the 154kV system configuration from a loop connection to a radial system, by splitting the bus where load balance can be achieved, and by upgrading the circuit breaker rating. A development project applying a 154kV Superconducting Fault Current Limiter (SFCL) to 154kV transmission systems is proceeding with implementation slated for after 2010. In this paper, SFCL is applied to reduce the fault current in power systems according to two different application schemes and their technical and economic impacts are evaluated. The results indicate that both application schemes can regulate the fault current under the rating of circuit breaker, however, applying SFCL to the bus-tie location is much more appropriate from an economic view point.

• Journal of IKEEE
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• v.22 no.3
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• pp.548-557
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• 2018

In this paper, Asynchronous Self-Power Gating technique (ASPG) is used to reduce consumption power in asynchronous digital watch application. The power gating control signal is automatically generated by internal system operation characteristics instead of using replica circuit delay or four-phase handshaking protocol. Isolation cell is designed to insert it between power gating domain and normal operation domain. By using self-power gating circuit, asynchronous digital watch application consumes very low power and maintains data during sleep mode. The comparison results show the proposed ASPG technique saves leakage power up to 40.47% and delay time is reduced to 71% compared to the conventional circuit.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.18 no.1
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• pp.39-48
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• 2012

Background: This study was performed to identify what effect plyometric exercise with application of kinesio taping gives on muscle activity and power of lower limb. Methods: In order to conduct research, total 14 male students at G university located Gwangyang city were randomly assigned; 7 for experimental group (with kinesio taping application) and 7 for control groups(without kinesio taping application) were conducted with box drill, one of the plyometric exercise 5 times a week for 4 weeks. Muscle activities were measured by using electrodiagnosis equipment on quadriceps and gastrocnemius. Collected data was analyzed by using Windows SPSS version 19.0. Results: Muscle activities show statistically significant differences (p<.05) both before and after exercise in experimental and control groups in terms of vastus medialis, rectus femoris, vastus lateralis and lateral gastrocnemius. However, only medial gastrocnemius shows statistically significant differences in experimental group compared before and after exercise. Sargent jump for measuring power shows that only experimental group presents statistically significant differences (p<.05). Two groups show that vastus medialis, vastus lateralis, lateral gastrocnemius and medial gastrocnemius only in muscle activities show statistically significant differences (p<.05) after exercise. Conclusion: The result of this survey indicates that plyometric exercise is effective to improve muscle activity and power of lower limb, especially, the group who exercises with application of kinesio tape is more effective than the other group with no tape application. Therefore, it is considered that plyometric exercise with tape is more effective to improve power and muscle strength.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.12-12
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• 1999