• The Korea Journal of Herbology
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• v.22 no.3
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• pp.101-107
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• 2007

Objective : This study was carried out to investigate diagnostic difference and anti-oxidative effect of 3 different Anemarrhenae Rhizoma (AR) extracts. Methods : Microscopic examination was used to distinguish histological differences. And eliminative ability of several kinds of free radicals was also measured. Results : In microscopic examination, we can distinguished three different lineage of AR with different structure of vascular bundles and secretory structures. The extract of AR show profitable abilities of elimination of DPPH free radical, ABTS free radical and hydrogen peroxide. Conclusion : So, it can be concluded that AR extract has an anti-oxidative effects. Especially indeciduous lineage was most effective to remove free radicals.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.06a
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• pp.183-184
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• 2014

최근 스마트 폰 가입자 수 증가와 함께 모바일 기기의 보급이 대중화 되었다. 모바일 기기 대중화로 다양한 형태의 멀티미디어 콘텐츠 소비가 많아지면서 새로운 콘텐츠를 요구하는 사용자들 늘어나고 있다. 다양한 소비 계층에서 콘텐츠의 수요가 늘어나고 있지만, 현재 시장에서는 공급량이 수요에 미치지 못하고 있다. 모바일 기기중 하나인 디지털 앱북 콘텐츠 또한 시장에서 더 많은 콘텐츠가 필요하다. 본 논문에서는 디지털 앱북의 콘텐츠 증가를 위해 디지털 앱북 제작에 있어 코드 재사용성 증가로 인한 체계적인 개발과 유지지보수의 용이함을 높이기 위해 사용자와의 다양한 상호작용 기능들을 라이브러리로 구현하고 검증하였다. 라이브러리는 사용자 동작부와 기기 동작부로 구성하고 각 동작부의 명령들을 조합하여 상호작용 메소드 형태로 존재하도록 설계하였다. 구현된 라이브러리는 코드 사용량을 크게 줄여 개발 시간 단축에 영향을 주어 디지털 앱북 콘텐츠 제작에 있어 효율을 높여준다.

• Journal of the Korean Statistical Society
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• v.29 no.3
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• pp.261-268
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• 2000

Let {Xn,n$\geq$1} be a sequence of pairwise negative quadrant dependent(NQD) random variables and let {an,n$\geq$1} and {bn,n$\geq$1} be sequencesof constants such that an$\neq$0 and 0$\infty$. In this note, for pairwise NQD random varibles, a general weak law of alrge numbers of the form(∑│aj│Xj-$\upsilon$n)/bnlongrightarrow0) is established, where {νn,n$\geq$1} is a suitable sequence. AMS 2000 subject classifications ; 60F05

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.915-925
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• 2012

On-off control performance of target pumping station was experimented by changing measurement methods for storage level or inflow and operating logic for control system setting. Four scenarios with different measurement methods and operational logic were examined in the Matlab/Simulink environment. Controller's on-off control repetition that was frequent before has been reduced and more effective and stable system operation was found to be possible with the scenarios. Moreover, defensive operation enforced prevention of floods by changing measurement methods enabled economic operation that made an utmost use of storage volumes.

• Proceedings of the Korean Vacuum Society Conference
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• 2007.02a
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• pp.67-67
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• 2007

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1214-1215
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• 2011

현재 HVDC 및 FACTS와 같은 전력전자소자 기반 전력기기의 최신 개발은 능동형 스위치소자의 발전 및 설치 환경의 변화로 인하여 VSC Topology로 이동되고 있다. 하지만 VSC Toplolgy의 스위칭 손실등의 문제로 대용량 전력기기의 경우 MMC(Modular Multilevel Converter) 적용이 가속화되고 있다. 이에 본 논문에서는 MMC Topology의 특징, 구동 원리, 시뮬레이션 과정을 소개한다. Modulation 및 Quantization 그리고 Sorting Algorithm을 통해 7-level, 151-level 삼상 MMC Topology을 시뮬레이션을 수행하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1798-1799
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• 2011

In this paper, A new cost-effective and accurate input noise rejection method for High Speed Counter module of PLC (Programmable Logic Controller) is proposed. By using combination of simple additional logic circuit and the Timer Pulse function of general purpose MPU, Cost-effectiveness and improvement of accuracy of filtering function can be achieved. This proposed method is verified by simulation. This proposed method is much useful for simple industrial controller based on simple microprocessor because of simplicity, accuracy and low cost.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1434-1435
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• 2011

In this study, NKN-LST ceramics were prepared by a conventional mixed oxide method and their structure and piezoelectric properties were investigated with the variations of sintering temperature. It was observed that the various sintering temperatures influenced the electrical properties and structural properties of the NKN-LST ceramics. It was found that the piezoelectric properties of NKN-LST ceramic sintered at $1080^{\circ}C$ for 4h has a piezoelectric constant and a planar electromechanical coupling coefficient of 161pC/N and 0.311% respectively. This ceramics look very promising as possible, practicable, lead-free replacements for lead zirconate titanate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.5
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• pp.434-437
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• 2004

Neural crest cells have embriologically important role for the development and growth in oral and maxillofacial region. If the early hereditary defect occurs or environmental factors affect these cells diminutive mesenchymal cells are disabled to make neural plate and decreased proliferation of mesenchymal cells result in hypoplastic development of neural crest. As a result, this brings about severe facial malformations such as various located facial clefts and/or loss or duplication of facial structure. These are two cases of accessory maxilla and zygomatic deformity with and without facial cleft.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.429-431
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• 1994

A parallel resonant dc link inverter, one of the many resonant inverters, has some superior characteristics in camparision with other resonant inverters. But loss of the resonant oscillation and occurrence of high peak voltage in the resonant capacitor of these inverters are serious problems. In this paper, we investigate a control method for resonant dc link inverters which can overcome these problems. Experimental results are presented to show superior operation of the resonant dc link inverter using the proposed control method.