• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.2044-2045
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• 2008

This paper was studied fault possibility of glass insulator through the proper vibration and field vibration comparison. The proper vibration of 1 cell glass insulator have many frequency band and high amplitude showed in high frequency than low frequency. The field signal amplitude of viaduct and open route were biggest moment pantograph of high-speed rail. From the FFT analysis of viaduct and open route, in the case of positive direction, the strut tube insulator effect by vertical vibration was big, the frequency was 82.5Hz and 105Hz, respectively. However, in the case of negative direction, the vibration did not cause big effect. In comparison with the proper vibration of glass insulator, the resonance was not observed.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2007년도 추계학술대회 논문집
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• pp.235-237
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• 2007

본 연구는 현장 분진포집에 의한 도전율측정과 전기설비 위험을 평가한 것이다. 현장에서의 분진발생은 전기설비에 악영향을 주어 전기설비의 운영시 발생되는 것과 주변환경적 요인에 의해 발생되는 분진이 주를 이루고 있다. 현장에서 포집된 분진으로부터 분진의 종류, 도전율 특성에 의해 전기설비가 영향을 미칠 것으로 판단되었다. 또한 일부 부식성 가스에 의해 노출된 전기설비의 위험성을 분석하고 관리기준을 마련할 필요가 있는 것으로 나타났다. 분진의 종류에 따라 사고의 과정은 빠르거나 오랫동안 지속되었다가 발생되는 근원적 원인을 규명하고자 국내현장에서 분포되고 있는 분진의 종류와 특성 분석과 관련규정을 검토하고 현장실태에서 나타난 문제점을 검토하여 분진발생지역에서의 전기설비 안전관리를 위한 기준마련에 이용될 것으로 기대된다.

• 한국수소및신에너지학회논문집
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• 제22권6호
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• pp.810-818
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• 2011

This paper analyzed the suitability about the isolation performance criteria which was based on human impedance and effect of current in IEC 60479-1 on the safety of human being was examined. The method of evaluation by megger and DC voltmeter was analyzed. The differences of isolation performance according to design of high-voltage system were analyzed. The factors which affect the insulation performance were analyzed for HFCV, EV, HEV, etc. through analysis of the isolation performance evaluation method. Finally, design for improved isolation performance was proposed.

• Nutritional Sciences
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• 제6권4호
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• pp.216-222
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• 2003

This study investigated the effects of feeding mulberry leaf extracts on lipid composition in rats fed high cholesterol diets. An initial 30-person sensory evaluation of preparations containing various concentrations of mulberry leaf extract showed that a preparation containing 9% mulberry leaf extracts was the most highly preferred. In addition, subsidiary materials of pine needle extracts and mugwort extracts were added to weaken the unpleasant smell of mulberry leaf extract A preparation containing 9% mulberry leaf extract with 3% mugwort extract and 7% pine needle extract was given highest preference scores by the 30-person panel. When comparing the functional ingredients contents of the various preparations of mulberry leaf extracts, such as GABA, DNJ and flavonoids, no significant differences were found as a result of adding subsidiary materials (pine needle and mugwort extracts). Sprague-Dawley male rats weighing l00$\pm$10g were randomly assigned to one normal diet group, and to four high cholesterol diet groups containing 1% cholesterol, to elucidate the functionality of the mulberry leaf extract The four high cholesterol diet groups were classified into: a mulberry leaf extract diet group free of subsidiary materials (EB group); a mulberry extract diet group with pine needle extracts (EP group); a mulberry leaf extract diet group with mugwort extracts (EM group); and a control group (HC group). The mulberry leaf extracts were provided as drinking water; the diet and water were fed ad libitum. Hepatic cholesterol and triglyceride levels were higher, by 279% to 475%, in the high cholesterol groups compared to the normal diet groups, but were significantly lower in the three groups supplied with mulberry leaf extracts, compared with the high cholesterol control. There were no changes in functionality of the mulberry leaf extract preparations due to the addition of subsidiary materials. In conclusion, preparations of mulberry leaf extracts were shown to improve lipid metabolism in rats fed a high cholesterol diet, by reducing hepatic and plasma triglyceride and cholesterol levels. Also human palatability of the mulberry leaf preparation was improved by adding subsidiary materials such as pine needle and mugwort extracts.

• International Journal of Safety
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• 제7권2호
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• pp.1-6
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• 2008

In this paper, the effects of the position and the angle of the potential probes on the measurements of the ground resistance using the fall-of-potential method are described and the testing techniques for minimizing the measuring errors are proposed. The fall-of-potential method is theoretically based on the potential and current measuring principle and the measuring error is primarily caused by the position and angle of auxiliary probes. In order to analyze the relative error in the measured value of the ground resistance due to the position of the potential probe, the ground resistance was measured for the case in which the distance of the current probe was fixed at 50[m] and the distance of the potential probe was located from 10[m] to 50[m]. Also, the potential probe was located in turn at $30[^{\circ}]$, $45[^{\circ}]$, $60[^{\circ}]$, $90[^{\circ}]$, and $180[^{\circ}]$. As a consequence, relative error decreased with increasing distance of the potential probe and decreasing angle between the current probe and potential probe. The results could help to determine the position of the potential probe during the ground resistance measurement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기설비전문위원
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• pp.273-275
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• 2008

본 논문에서는 하이브리드자동차(hybrid vehicle)의 고전원 전기장치 및 전기배선 충전부의 인체 접촉에 의한 감전사고의 예방을 위한 전기적 연속성의 측정방법에 대하여 논하였다. 인체 감전 보호를 위한 기본 대책으로 충전부의 기본절연, 충전부 접근에 대한 보호(배리어, 인클로져 등)가 있다. 하이브리드자동차의 전기적 연속성과 관련된 시험방법은 UNECE, ISO, Japan Attachment 등에서 언급하고 있다. 이들 기준에서 전기적 연속성은 $0.1{\Omega}$ 이하를 유지하도록 하고 있다. 본 연구에서는 하이브리드자동차의 전기적 연속성 측정 방법에 있어 외국의 기준과 규격의 내용을 검토하고 전기적 연속성 측정방법을 제시하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1385_1386
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• 2009

In this paper, we examined the faulted cable joint through the external form analysis, material analysis, experimental verification and it's cause diagnosis system. It was not observed the voild, sharp material from the external form analysis and material variation. From the experimental verification, the thickness decrease of an insulator decreased ac breakdown strength suddenly and the breakdown traces of the insulator that was damaged by knife displayed elliptic shape. Thus, the faulted cable is assumed to accident that become dielectric breakdown by the deterioration of insulation performance that can happen when work.

• 건축역사연구
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• 제20권2호
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• pp.55-70
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• 2011

This paper aimed at analyzing of structural carpentry terminology for bracket structure in Yingzaofashi ${\ll}$營造法式${\gg}$in the era of Song Dynasty and illuminating coinage characteristics and method of Structural Carpentry Terminology for bracket Structure through graphonomy research and system and structure of these terms. The results are as follow. The structural carpentry terminologies for structure were identified to be approximately 23 words, and terminology of bracket structure鋪作 is largely categorized into 3 categories of Type鋪作次序, Structure, Place. On the other hand, the structural carpentry terminologies for parts largely categorized into 2 categories of Bracket structure鋪作, Others. Bracket structure terminologies for parts were derived from the core of Dou枓, Gong栱, Ang昂, Fang方. The phenomena of derivation in structural carpentry terminology for bracket structure can be explained by the difference in the shape of subsidiary material and the location for usage of the subsidiary material and part of the subsidiary material and their functions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 춘계학술대회 논문집 전기설비전문위원
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• pp.219-221
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• 2009

본 논문에서는 전기설비의 전기적 접속부 또는 전기배선 등에서 발생하는 발열상태를 실시 간으로 모니터링하는 전력설비 진단시스템에 사용되고 있는 광온도센서에 대하여 열원에 따른 동작특성을 실험, 분석하였다. Heimann Sensor사의 광온도소자를 이용하여 광온도센서를 제작하여 실험에 사용하였으며, 열원으로는 Black Body와 Hot Plate를 사용하였으며 각각에서의 열원의 온도변화에 따른 광온도센서의 출력전압값을 측정, 비교 분석하였다. 실험결과, Black Body에 의한 온도 측정이 Hot Plate에서보다 더 정밀함을 확인할 수 있었다. 이러한 분석 결과는 향후, 전력설비 진단시스템의 현장 적용에 있어 광온도센서의 출력값과 실측값의 매칭을 위한 기본 자료가 될것으로 기대된다.

• Journal of Communications and Networks
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• 제9권1호
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• pp.1-10
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• 2007

This paper proposes a multimodal generalized Gaussian distribution (MGGD) to effectively model the varying statistical properties of the extrinsic information. A subsidiary maximum likelihood decoding (MLD) algorithm is subsequently developed to dynamically select the most suitable MGGD parameters to be used in the component maximum a posteriori (MAP) decoders at each decoding iteration to derive the more reliable metrics performance enhancement. Simulation results show that, for a wide range of block lengths, the proposed approach can enhance the overall turbo decoding performance for both parallel and serially concatenated codes in additive white Gaussian noise (AWGN), Rician, and Rayleigh fading channels.