• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.8-8
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• 2000

Recently the study of the pseudo-gap in high temperature superconductivity become critical issue because it contains key information of the pair formation of the high temperature superconductivity. Specially angle resolved photoemission study shows the various information of the gap formation. In this talk, I will review the recent theories as will as experiments on the pseudo-gap in high temperature superconductors. Specially I will introduce the possible observation of the Andreeve reflection in the underdopped high temperature superconductors.

• 한국초전도ㆍ저온공학회논문지
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• 제18권2호
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• pp.14-17
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• 2016

Annealing as-grown electron-doped cuprates under a low oxygen-partial-pressure condition is a necessary step to achieve superconductivity. It has been recently found that the so-called protect annealing results in much better superconducting properties in terms of the superconducting transition temperature and volume fraction. In this article, we report on angle-resolved photoemission spectroscopy studies of a protect-annealed electron-doped cuprate $Pr_{0.9}La_{1.0}Ce_{0.1}CuO_4$ on annealing condition dependent superconducting and pseudo-gap properties. Remarkably, we found that the one showing a better superconducting property possesses almost no pseudo-gap while others have strong pseudo-gap feature due to an anti-ferromagnetic order.

• Progress in Superconductivity
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• 제11권2호
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• pp.83-86
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• 2010

There are theoretical and experimental evidences for the pseudo-gap in electron doped cuprates being due to interaction between electrons and anti-ferromagnetism(AFM). A remaining issue is on how AFM correlates with pseudo-gap, and eventually with superconductivity. To elucidate the issue, we have performed temperature dependent angle-resolved photoemission studies of an e-doped cuprate superconductor $Sm_{2-x}Ce_xCuO_4$(SCCO) x=0.18 at 20K and 150K. In the case of $Nd_{2-x}Ce_xCuO_4$, the most well known e-doped cuprate, pseudo-gap disappears at around 100 K for x=0.17. Our experimental result reveals that the pseudo-gap of SCCO exists even at 150K for x=0.18. This result implies that the AFM of SCCO survives even in x=0.18, which agrees with previously reported phase diagram of SCCO. Yet, the superconductivity disappears around x=0.18 for both NCCO and SCCO in spite of the difference in the magnetic order. This result sheds a light on the disappearance of superconductivity on the over-doped side.

• 한국자기학회지
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• 제4권2호
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• pp.130-134
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• 1994

본 연구에서는 MIG 헤드의 재생 전압 스펙트럼에 나타나는 Bump들의 발생 원인을 설명하고, 이론적으로 예상된 주파수에서 Bump들의 진폭을 컴퓨터로 시뮬레이션 하였다. MIG 헤드의 센더스트와 페라이트 사이의 가상 갭(pseudo gap)이 없는 경우와 양쪽 모두 $0.02\;\mu\textrm{m},\;0.2\;\mu\textrm{m}$, 인 가상 갭을 갖는 3가지 종류의 MIG 헤드들을 설정하고, 금속 분말(Metal Powder) 테입을 사용한 것으로 가정하였다. 시뮬레이션 결과, 이론적으로 예상한 주파수에서 Bump들이 발생하였으며, Bump 진폭 또한 예상치와 거의 일치하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.11-11
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• 2011

In this talk, I will discuss roles of pseudo vector and scalar potential in changing physical properties of graphene systems. First, graphene under small uniaxial strain is shown to be described by the generalized Weyl's Hamiltonian with inclusion of pseudo vector and scalar potential simultaneously [1]. Thus, strained graphene is predicted to exhibit velocity anisotropy as well as work function enhancement without any gap. Second, if homogeneous strains with different strengths are applied to each layer of bilayer graphene, transverse electric fields across the two layers can be generated without any external electronic sources, thereby opening an energy gap [2]. This phenomenon is made possible by generation of inequivalent pseudo scalar potentials in the two graphene layers. Third, when very tiny lateral interlayer shift occurs in bilayer graphene, the Fermi surfaces of the system are shown to undergo Lifshitz transition [3]. We will show that this unexpected hypersensitive electronic topological transition is caused by a unique interplay between the effective non-Abelian vector potential generated by sliding motions and Berry's phases associated with massless Dirac electrons.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.14-14
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• 2006

• JSTS:Journal of Semiconductor Technology and Science
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• 제5권2호
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• pp.83-88
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• 2005

The interface-states between the top silicon layer and buried oxide layer of nano-SOI substrate were developed. Also, the effects of thermal treatment processes on the interface-state distributions were investigated for the first time by using pseudo-MOSFETs. We found that the interface-state distributions were strongly influenced by the thermal treatment processes. The interface-states were generated by the rapid thermal annealing (RTA) process. Increasing the RTA temperature over $800^{\circ}C$, the interface-state density considerably increased. Especially, a peak of interface-states distribution that contributes a hump phenomenon of subthreshold curve in the inversion mode operation of pseudo-MOSFETs was observed at the conduction band side of the energy gap, hut it was not observed in the accumulation mode operation. On the other hand, the increased interface-state density by the RTA process was effectively reduced by the relatively low temperature annealing process in a conventional thermal annealing (CTA) process.

• 방송공학회논문지
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• 제26권7호
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• pp.844-854
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• 2021

Semi-supervised learning (SSL) and few-shot learning (FSL) have shown impressive performance even then the volume of labeled data is very limited. However, SSL and FSL can encounter a significant performance degradation if the diversity gap between the labeled and unlabeled data is high. To reduce this diversity gap, we propose a novel scheme that relies on an autoencoder for generating pseudo examples. Specifically, the autoencoder is trained on a specific class using the available labeled data and the decoder of the trained autoencoder is then used to generate N samples of that specific class based on N random noise, sampled from a standard normal distribution. The above process is repeated for all the classes. Consequently, the generated data reduces the diversity gap and enhances the model performance. Extensive experiments on MNIST and FashionMNIST datasets for SSL and FSL verify the effectiveness of the proposed approach in terms of classification accuracy and robustness against adversarial attacks.

• 대한전자공학회논문지SD
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• 제41권8호
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• pp.59-65
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• 2004

본 논문에서는 IT(In-plane switching foisted nematic) 모드를 기반으로 광 투과 특성을 개선시킨 Pseudo-TN IPS(Pseudo-Twisted Nematic In-Plane Switching) 모드를 새롭게 제안하고 그 광 투과 특성을 분석하였다. PTN-IPS 모드의 경우 개구율을 향상시켜 투과율 면적을 향상시킴으로써 종래의 IT 모드보다 약 25%정도의 높은 광 투과 특성을 나타내었으며, 전압인가에 따른 광 투과율의 변화가 선형적이므로, 광 투과율 조절을 위한 액정의 제어가 IT 모드에 비해 용이함을 확인하였다. 또한, IT 모드에 비해 수평방향 대비비는 약 8%정도 특성이 열화 되었으나 수직 방향에 있어서는 약 20%이상의 특성개선을 확인 할 수 있었다. 이와 더불어, 기존 IT 모드가 가지고 있는 샐 갭에 대한 특성 및 장점을 가지고 있어, 차세대 액정 셀을 개발하는데 유용하게 사용될 것이라 생각된다.

• 한국콘텐츠학회논문지
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• 제18권7호
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• pp.1-9
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• 2018

본 연구는 '언론의 자유' 권리와 '유사언론 행위'라는 주장에 의거한 온라인 신문 규제 주장 간의 충돌 현상을 법적 윤리적 쟁점에 따라 세분화하였다. 이를 위해 2012년부터 2017년까지 온라인 매체 상에 존재하는 현대식 마녀사냥 현상과 관련한 사건들을 조사해 유사언론 행위, 사이비언론 행위에 대한 규제 주장의 근거와 연관 지어 해석하였다. 또한 윤리적 논쟁이 되는 반대 의견으로 언론의 자유와 책임, 이에 반하는 명예권과 프라이버시 권리 등이 충돌할 경우 우선시 되는 권리에 대한 과거 연구들을 종합하고, 5인 이하 소규모 온라인 신문사의 언론의 자유 권리에 대한 최근의 판례 등을 정리하였다. 각 주장의 근거로써 실질 현상으로 나타난 사례들과 이에 대립하는 의견들의 논거 비교를 통해 현재 논쟁 중인 온라인 매체상의 뉴스 행위의 법적 윤리적 문제에 대해 종합적으로 고찰하였다.