• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.295-297
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• 2005

EDI는 기업과 기업간의 거래에서 종은 방법이지만 중소기업이나 소기업에서는 EDI의 도입이 기술적으로나 비용적으로 어려운 게 사실이다. 이 경우 ebXML을 이용하여 EDl를 대신할 수 있다. ebXML을 이용하여 B2B환경을 구축할 경우 ebXML문서를 서로 주고 받는데 메시징 서비스 엔진이 필요하게 된다. 본 연구에서는 ebXML기반의 B2B환경에서 활용할 수 있는 메시징 서비스 엔진을 설계하고 구현하였다. 또한 실제 ebXML메시지를 전송할 때 발생하는 오류를 해결하기 로그를 기록하여 분석할 수 있도록 개발하였다.

• Annals of Clinical Neurophysiology
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• v.10 no.2
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• pp.112-115
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• 2008

Colchicine is a drug used for the treatment of acute gouty arthritis or various autoimmune diseases. Gastrointestinal adverse effects such as abdominal pain and vomiting are the common side effects of the drug, but rarely myopathy has been reported to occur particularly in renal recipients who were treated concomitantly with immunosuppressants. Herein, we report a case who presented with acute myopathy after treated with colchicine for acute gouty arthritis.

• New & Renewable Energy
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• v.7 no.4
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• pp.58-65
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• 2011

In variable-speed variable-pitch wind turbines, the conventional approach for controlling power-production operation relies on a generator-torque controller and a rotor-collective blade-pitch controller. Both controllers use the generator speed measurement as the sole feedback input. In order to mitigate unwanted excitation of the control system, many filters are adopted. In this study, the characteristics of some filters for signal processing are investigated based on frequency response function. They include low-pass filters, band-pass filters, and notch filters. Especially, this study focuses on design parameters of their filters.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1600-1609
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• 2016

As the penetration of different types of renewable energy sources (RES) and energy storage systems (ESS) increases, the importance of stability in AC microgrid is being emphasized. Especially, RES and ESS which are operated using power electronics have difference in output characteristics according to control structures. When faults like single-line-to-ground fault or islanding operation occur, this means that a fault should be interpreted in different way. Therefore, it is necessary to analyze fault characteristics in AC microgrid in case of grid-connected mode and standalone mode. In this paper, the fault analysis for AC microgrid is carried out using PSCAD/EMTDC and an overvoltage problem and the countermeasures were proposed.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.159-160
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• 2013

본 논문에서는 연료전지를 사용하여 2차 전지를 충전시키는 동기식 부스트 컨버터를 제어하는 방식을 제안한다. 고효율을 위한 동기식 부스트 컨버터는 기존의 부스트 컨버터의 다이오드 대신 MOSFET을 사용한다. 이때 연료전지의 전압이 배터리의 전압보다 낮기 때문에 양방향 소자인 MOSFET의 특성상 DCM구간에서 역전류가 발생한다. 연료전지의 긴 기동시간으로 인해 초기 동작 시 소프트 스타트가 필요한데 이때 역전류가 발생할 수 있는 DCM구간이 나타난다. 시스템 제어를 위해 사용된 mode boundary detector은 CCM과 DCM을 구분해주어 컨버터를 제어한다. CCM구간에서는 동기식으로 부스트 컨버터가 동작되고 DCM구간에서는 기존의 다이오드를 사용하는 방식으로 역전류를 방지한다. 시뮬레이션을 통해 논문의 타당성을 증명하였다.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.428-431
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• 1990

This paper describes a pattern classification algorithm of QRS-complexes using significant point detection for extracting features of signals. Significant point extraction was processed by zero-crossing method, and decision function based on relational spectrum was used for pattern classification of the QRS-complexes. The hierarchical AND/OR graph was obtained by decomposing the signal, and by use of this graph, QRS's patterns were classified. By using the proposed algorithm, the accuracy of pattern classification and the processing speed were improved.

• 대한예방의학회:학술대회논문집
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• 1995.10a
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• pp.141-142
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• 1995

• Journal of Korea Multimedia Society
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• v.13 no.6
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• pp.865-874
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• 2010

Recently, Hao et al. proposed a privacy preservation protocol based on group signature scheme for secure vehicular communications to overcome a well-recognized problems of secure VANETs based on PKI. However, although efficient group signature schemes have been proposed in cryptographic literatures, group signature itself is still a rather much time consuming operation. In this paper, we propose a more efficient privacy preservation protocol than that of Hao et al. In order to design a more efficient anonymous authentication protocol, we consider a key-insulated signature scheme as our cryptographic building block. We demonstrate experimental results to confirm that the proposed protocol is more efficient than the previous scheme.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.602-605
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• 2007

Soybean and rape seed are common feedstocks for biodiesel product ion in USA and Europe, respectively. On the other hand, South Eastern countries like Malaysia and Indonesia have surplus palm crops. However due to substantial amount of saturated fats in palm, the palm biodiesel has poor low temperature properties. To improve the low temperature flow properties as biodiesel, the dependence of the cold filter plugging point (CFPP) on the fatty acid compositions was examined. Two different kinds of biodiesels, palm and soybean biodiesels, were blended with the different volume ratios. And the low temperature flow properties of 0.5%, 1%, and 5% biodiesel in diesel blend fuels was tested. The decrease of CFPP was not observed for BD1 with Palm BD. Also, WDI test didn't exceed in the range of 4oC by the mixing of Palm BD upto 5% in commercial diesels.

• Journal of Korean Neurosurgical Society
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• v.40 no.5
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• pp.381-383
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• 2006

Spinal extradural arachnoid cyst is uncommon and rarely cause neural compression. We report a rare case of severe cord compression due to septated spinal extradural arachnoid cyst. A 35-year-old woman has developed back pain 3 months prior to her visit, but recently motor weakness and urinary incontinence occurred. Magnetic resonance images showed an extradural cyst posterior to the cord, which was flattened and displaced from T12 to L2. Urgent decompressive laminectomy and cyst removal was performed. Histopathological examination confirmed that cyst wall was formed by nonspecific fibrous connective tissue without a single-cell layer of inner arachnoid lining. Motor weakness and voiding difficulty were recovered completely after operation.