• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권3호
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• pp.139-144
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• 2005

[ $SF_6$ ] gas circuit breakers are widely used short circuit current interruption in EHV or UHV power system. For a $SF_6$ gas circuit breaker development, the $SF_6$ gas velocity measurement is necessary during $SF_6$ circuit breaker's trip operation. Small-gap flashover characteristics are used for this measurement. So, small-gap measuring system which will be used to develope GCB should be developed. This study shows the characteristic analysis and experimental results of small-gap measuring system.

• ETRI Journal
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• 제18권3호
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• pp.181-193
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• 1996

A blue light emitting device has been successfully fabricated using a polymer with regulated conjugation length containing trimethylsilyl substituted phenylenevinylene units. Electroluminescence from the device has an emission maximum at 470 nm. The device shows typical diode characteristics with operating voltage of 20 V and the light becomes visible at a current density of less than $0.5;mA/cm^2$. The electroluminescence spectrum is virtually identical with the photoluminescence spectrum, indicating that the radiation mechanisms are the same for both. A light emitting device using the blend of a large band gap polymer and a small band gap polymer was also fabricated. Light emission from the small band gap polymer shows much improved quantum efficiency, but there is no light emission from the large band gap polymer. Quantum efficiency of the blend increases up to about two orders of magnitude greater than that of the small band gap polymer with increasing proportion of the large band gap polymer. The improvement in quantum efficiency is interpreted in terms of exciton transfer and the hole blocking behaviour of the large band gap polymer. Finally, we have fabricated a patterned flexible light emitting device using the high quantum efficiency polymer blend system.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권3호
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• pp.155-158
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• 2006

$SF_6$ gas circuit breakers we widely used for short circuit current interruption in EHV or UHV power system. For a $SF_6$ gas circuit breaker development, the hot gas velocity measurement is necessary during $SF_6$ gas circuit breaker's trip operation. Small-gap flashover characteristics are used for this hot gas velocity measurement. This study sho was the hot gas velocity measurement results during $SF_6$ gas circuit breaker' trip operation.

• 노동경제논집
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• 제42권1호
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• pp.43-72
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• 2019

Oaxaca의 임금격차 요인분해법을 활용하여 대기업과 중소기업의 임금격차를 분해한 결과, 공급측 요인의 총임금격차는 44.2%였으며, 근속연수와 학력이 가장 크게 영향을 미쳤다. 그리고 기업의 경영실적 등 수요측 요인에 의한 기업 규모별 임금격차를 분해한 결과, 총임금격차는 44.9%였으며, 임금격차에 미치는 영향력은 노동생산성, 노조, 외주비율 순으로 컸다. 이러한 분석결과는 기업 규모별 임금격차를 해소하기 위해서는 인적자본의 차이 등 공급측 요인뿐만 아니라 기업의 경영실적과 자본구조 등 수요측 요인도 함께 고려할 필요가 있음을 시사한다.

• Parasites, Hosts and Diseases
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• 제50권1호
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• pp.89-93
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• 2012

$Neodiplostomum$ $seoulense$ (Digenea: Neodiplostomidae) is an intestinal trematode that can cause severe mucosal pathology in the small intestines of mice and even mortality of the infected mice within 28 days after infection. We observed neuronal growth associated protein-43 (GAP-43) expression in the myenteric plexus of the small intestinal wall of $N.$ $seoulense$-infected mice until day 35 post-infection (PI). BALB/c mice were infected with 200 or 500 $N.$ $seoulense$ metacercariae isolated from naturally infected snakes and were killed every 7 days for immunohistochemical demonstration of GAP-43 in the small intestines. $N.$ $seoulense$-infected mice showed remarkable dilatation of intestinal loops compared with control mice through days 7-28 PI. Conversely, GAP-43 expression in the mucosal myenteric plexus was markedly ($P$<0.05) reduced in the small intestines of $N.$ $seoulense$-infected mice during days 7-28 PI and was slightly normalized at day 35 PI. From this study, it is evident that neuronal damage occurs in the intestinal mucosa of $N.$ $seoulense$-infected mice. However, the correlation between intestinal pathology, including the loop dilatation, and depressed GAP-43 expression remains to be elucidated.

• 대한인간공학회지
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• 제31권2호
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• pp.363-370
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• 2012

Objective: The objective of this study is to analyze standards of ISO 9001, ISO 14001, KOSHA 18001, GAP and ISO 22000 to make an integrated system and check whether an integrated system can be used at small size companies. Background: There are many certification criteria for quality, safety and health such as ISO 9001, ISO 14001, KOSHA 18001, GAP and ISO 22000. However, these criteria are difficult and complicated to be used at a small size company. Thus. it is not easy for small size companies to obtain certifications using these criteria. But customers and workers of small size companies want the key points of these systems to be implemented. Method: ISO 9001, ISO 14001, KOSHA 18001, GAP and ISO 22000 were analyzed to find the commonality and duplications as well as the importance of the items in these standards. And a survey was conducted to check whether certain aspects of the anticipated integrated system can be implemented at small size companies. Results: Items were classified into categories based upon the importance to food safety, quality, safety, environment, and health. Items which are common among standards were also identified and thus give ideas to make the new standards simpler than the currently available standards. Items which were important but may not be easily implemented at the small size companies were also identified. Conclusion: By considering the fact that the currently used accreditation standards have many similar aspects, these systems can be integrated into one new system which small size companies can use relatively easily.

• 대한수학회보
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• 제37권2호
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• pp.353-360
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• 2000

The fundamental gap between the lowest two Dirich-let eigenvalues for a Schr dinger operator HR={{{{ { { d}^{2 } } over { { dx}^{2 } } }}}}+V(x) on L({{{{ LEFT | -R,R RIGHT | }}}}) is compared with the gap for a same operator Hs with a different domain {{{{ LEFT [ -S,S RIGHT ] }}}} and the difference is exponentially small when the potential has a large barrier.

• Journal of Welding and Joining
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• 제34권1호
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• pp.68-74
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• 2016

Adoption of narrow gap welding shall be increased for the butt joint of thick plate, because the deformation and welding cost is reduced by decrease of cross-sectional area. However, sometimes narrow gap causes defects such as lack of fusion since it has small groove angle and narrow groove width. Therefore, GMAW, GTAW and SAW process shall be adopted to narrow gap welding with small bead hight and low deposition rate. In this study, Super-TIG welding using C-type strip was applied to semi-narrow gap butt joint in order to increase the welding productivity. High deposition rate 10kg/hr was obtained by high current 600A without undercut, humping bead and other welding defects. Measuring the mean and standard deviation of the melting depth to evaluate the developed processes, the fusion line type was determined by measuring the difference between maximum and minium melting depth. Furthermore, a model on arch fusion line and linear fusion line was suggested in order to prevent LF on groove wall in narrow gap butt welding.

• 한국전기전자재료학회논문지
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• 제16권10호
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• pp.914-922
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• 2003

The FFS (fringe-field switching) mode was known to exhibit both a wide viewing angle and high transmittance, especially when using a liquid crystal with negative dielectric anisotropy. We have studied cell gap-dependent electrode-optic characteristics of the FFS mode using the LC with negative dielectric anisotropy. In case of a small cell gap of 2 ${\mu}$m, the transmittance at the center of pixel and common electrodes is relatively low because effect of surface anchoring that holds the LC to the initial state is larger than that in a large cell gap of 4 .urn such that the LCs in those regions cannot rotate enough. However, in case of a large cell gap of 4 .urn, the effect of surface anchoring becomes relatively small so that the LCs at the center of pixel and common electrode can be twisted enough by applied voltage, giving rise to high transmittance. Therefore, we can conclude that the light efficiency is dependent on the cell gap.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1031-1032
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• 2007

Gap servo NF (Near Field) system is one of technologies to reduce beam spot size by increasing NA (Numerical Aperture) of lens. To achieve higher NA, SIL (Solid Immersion Lens) is used. In the case of using a blue LD (405 nm) as the light source the gap distance should be controlled under 100 nm with much tighter margin. Because of very small gap distance between SIL bottom and the surface of media, relative tilt tolerance is limited. In this paper, we presented 2-axis tilt mechanism for skew adjustment within small tilt margin.