• Journal of Industrial Technology
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• v.34
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• pp.71-78
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• 2014

Recently, using the electronic devices was increased with semiconductor developments. So, the EMI(Electromagnetic interference) problem become to important issue for coexistence with each electronic devices. The EMI is caused by switching operation from the power switches as the FET and the transistor in power conversion devices. In this paper, the hybrid EMI filter that composed with active components and passive components was described. The EMI filter is applied to the 160 watts LED driver experimentally verify the performance. The hybrid EMI filter is compared with non-filter, only passive filter and only active filter. The proposed EMI filter attenuated CM noise more than traditional passive filter.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.621-623
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• 2005

OPC has made it to improve the development of control and monitoring software. But it is difficult to understand COM/DCOM model that is a base technology of OPC and complex communication setting between OPC Server and OPC Client. Therefore, in this paper, we design and implement ActiveX based components that are enable to solve these problems. Implemented components provide a method for simple communication between OPC Server and OPC Client and a GUI environment for easy and fast setting of communication information. Also, they provide the architecture for efficient management of OPC Server's data. By using implemented component, easy development and efficient maintenance of OPC Client can be supported.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.1
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• pp.41-47
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• 2012

This paper proposes a calculation of compensation current using phase shift to eliminate ripple components of instantaneous active power under unbalanced or non-linear loads condition. The proposed phase shift method instead of existing method(LPF; Low Pass Filter) to remove ripple components and this proposed method improves performances of transient and steady state response. To compare proposed method with existing method, experiments have been done for calculating an average active power at load side. Their results show that transient response and steady state response of proposed method is improved.

• KSBB Journal
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• v.8 no.3
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• pp.300-305
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• 1993

In order to explore the brassinosteroid-active components in Zea mays seeds, the methanol extract was purified by the sequences of solvent fractionation, silica gel adsorption chromatography, Sephadex LH-20 chromatography, charcoal adsorption chromatography and Bondesil chromatography. The activity of brassinosteroid was monitored by the rice inclination test and its presence could be confirmed in each purification step. The purified active components were separated by silica gel adsorption chromatography. Brassinosteroid substances in separated active fractions were identified as castasterone and teasterone by HPLC. The content of brassinosteroid in Zea mays seeds as converted into brassinolide was 3-8ng/g fresh weight.

• Proceedings of the KIPE Conference
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• 2019.07a
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• pp.4-5
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• 2019

본 논문은 DC마이크로그리드에서 저전압 배터리 에너지 저장 시스템과 DC 버스 연결을 위한 Dual Active Bridge(DAB) 컨버터의 제어 방법에 대한 연구이다. DC 마이크로그리드에서 전력을 효율적으로 사용하기 위해 양방향 전력전달이 쉬운 DAB 컨버터는 많이 사용되고 있다. 다만, 낮은 배터리 저장 시스템을 사용하는 경우 과도상태에서 DC 버스 측 커패시터를 충전하기 위해 높은 돌입전류가 발생하게 된다. 이러한, 높은 돌입전류는 시스템의 전력반도체 소자를 파손시키는 문제를 가져온다. 따라서, 초기 돌입전류를 저감시킬 수 있는 소프트 스타트 알고리즘이 필요하다. 본 논문에서는 돌입전류 저감을 위한 소프트 스타트 알고리즘을 제안하고, 3kW급 DAB 컨버터의 실험 결과를 바탕으로 제안 된 알고리즘을 검증하였다.

• YAKHAK HOEJI
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• v.28 no.4
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• pp.231-235
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• 1984

Active principles for the anti-fatigue activity of Panax ginseng were studied in mice using the swimming performance method. Ginseng water extract maximized the prolongation of swimming time 18 hours after administration. The potencies of anti-fatigue activities were found as in the order of ether soluble fraction and butanol soluble fraction as those of antioxidant activities previously determined. The anti-oxidant components, maltol, salicylic acid and vanillic acid isolated from the ether soluble fraction of Panax ginseng strongly exhibited the antifatigue activities, where as highly purified crystalline ginsenoside $4Rb_1$, Re and $4Rg_1$ did not.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.406-411
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• 2005

In this paper, we propose an active 90$^{\circ}$ phase divider for application to MMIC. Because of their very large size, conventional passive 90$^{\circ}$ dividers can't be integrated on MMIC. Therefore, highly miniaturized 90$^{\circ}$ dividers are required for a development of highly integrated MMIC. For this reason, active 90$^{\circ}$ divider is indispensable because active phase divider is much smaller than conventional passive dividers, and it can be integrated on MMIC. In this work, we developed active 90$^{\circ}$ divider with emitter inductor, and it was employed for the operation of the balanced mixer in order to verify the performance of the active 90$^{\circ}$ divider. According to the results, it was found that the active 90$^{\circ}$ divider exhibited good RF performances comparable to conventional passive power dividers.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1605-1606
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• 2013

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.149.1-149.1
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• 2003

Active ingredients, therapeutic and adverse effects of Aloe vera were comprehensively investigated. Aloe vera contains active components. including sugars, proteins, lipids, vitamins, minerals, phenolic compounds and other several compounds like phthalate esters, gibberellin, lectin-like substances, lignin, saponins, salicylic acid and uric acid. (omitted)

• YAKHAK HOEJI
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• v.17 no.4
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• pp.245-248
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• 1973

Four main components of plants produced in Korea were subjected to the screening test of antineoplastic activity against Ehrlich ascites carcinoma, SN 36 leukemia and sarcoma 180. Of the four components, bilobol showed comparatively active survival effect.