• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.285-287
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• 1999

Power System Stabilizer is designed to improve dynamic stability and umdamped power angle oscillations through the application of supplementary stabilizing of excitation control. The object of this paper is to describe the design considerations of microprocessor based Power System Stabilizer especially in hardware design.

• Journal of Electrical Engineering and Technology
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• 제11권5호
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• pp.1057-1062
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• 2016

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.76-79
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• 2004

This research was carried out to evaluate role of supplementary reagents, such as phosphate and SDS, to remove hydrophobic organic contaminant from soils during the EK-Fenton process. The $H_2O$$_2$ stability improved due to the role as stabilizer of phosphate and SDS during the EK-Fenton process. Furthermore, although pH in region near cathode was 8.2 after test, $H_2O$$_2$ stability improved due to transportation of SDS in the region near cathode. Therefore, in tests using phosphate and SDS as supplementary reagent, the efficiency of phenanthrene treatment improved through the EK-Fenton process using longer reaction time.

• Journal of Electrical Engineering and Technology
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• 제7권5호
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• pp.664-671
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• 2012

This paper presents the application of Unified Power Flow Controller (UPFC) in order to simultaneous control of power flow and voltage and also damping of Low Frequency Oscillations (LFO) at a Single-Machine Infinite-Bus (SMIB) power system installed with UPFC. PI type controllers are commonly used controllers for UPFC control. But for the sake of some drawbacks of PI type controllers, the scope for finding a better control scheme still remains. In this regard, in this paper the new IP type controllers are considered as UPFC controllers. The parameters of these IP type controllers are tuned using Genetic Algorithms (GA). Also a stabilizer supplementary controller based UPFC is considered for increasing power system damping. To show the ability of IP controllers, this controller is compared with classical PI type controllers. Simulation results emphasis on the better performance of IP controller in comparison with PI controller.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.427-434
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• 2000

Hydraulic conductivity of soil-cement was measured as a function of some selected construction variables that are often encountered in practice. They are initial (or compaction) water content, delayed compaction after mixing, and repeated freezing and thawing. Sandy and clayey soils were used. The hardening agent used was a cement based soil stabilizer consisting of 80% of ordinary Portland cement and 20% of a combination of supplementary materials. Hydraulic conductivity of soil-cement with varying initial water content was, in trend, similar to that of compacted clay. Hydraulic conductivity of soil-cement decreased with increasing initial water content and reached its minimum when compacted wet of optimum water content. Pore size distributions of soil cement at different initial water contents were analyzed using mercury intrusion porosimetry. The analysis showed that dryer condition led to the formation of larger pores with lesser total pore volume; smaller pores with larger total pore volume at wetter condition. Hydraulic conductivity of soil-cement increased by orders in magnitude when specimen underwent delayed compaction of longer than 4 hours after mixing and repeated freezing and thawing.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.95-98
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• 1996

Response speed of generator/control system kas increased with the aid of the development of power electronics. Even though it is desirable to enhance response speed for the control system(AVR/Gov) of generator itself, in case a certain generator/control system with high response excitation system is connected with bulk power system, terminal voltage and active power of some generators can oscillate with adjoining generators or near area when even a little of disturbance take place. PSS(Power System Stabilizer) is used to damp rotor swing by adding the supplementary signal in phase with speed. As the stable AVR response is very important before PSS is installed, modeling and analysis of generator/control system was performed. Next we have analysed PSS response of Hanlim's gas turbine by transmission line open/close test.

• 자원환경지질
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• 제57권4호
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• pp.417-429
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• 2024

안정화 공법이 토양 내 As 및 중금속의 작물 전이에 미치는 영향을 평가하기 위해 안정화제를 적용한 오염 토양에 벼를 재배하는 포트 실험을 수행하였다. 안정화제는 유기 안정화제로 바이오차, 무기 안정화제로 석회석·제강슬래그 혼합물, 미생물학적 안정화제로 황산염환원균(SRB)을 사용하였다. 토양수 분석 결과, 실험종료(153일) 시점에 미생물학적 안정화제 조건에서 Pb, Cu, Cd의 높은 안정화 효율을 보였으며, SRB와 SO₄^2-가 함께 주입된 조건에서 더 높은 효율을 나타내었다. 안정화제 투입 조건에서 벼의 줄기, 잎, 왕겨로의 Pb, Zn, Cu, Cd의 전이가 감소하였으며, 특히 왕겨에서 Pb, Zn, Cu, Cd의 안정화 효율은 유기 안정화제가 30~65%, 무기 안정화제가 23~69%로 미생물학적 안정화제보다 높은 안정화 효율을 보였다. 이 연구는 논토양에서 작물로의 중금속 전이를 저감할 때, 널리 사용되는 안정화제인 석회석, 제강슬래그, 바이오차의 대체 또는 보조 안정화제로서 SRB가 효과적으로 적용될 수 있는 가능성을 나타낸다.