• 제목/요약/키워드: Unbalanced rate

검색결과 152건 처리시간 0.022초

불평형 마그네트론 스파터링에 의한 AC PDP용 MgO 보호층의 최적형성조건에 관한 연구 (A Study on the Optimum Preparation Conditions of MgO Protecting Layer in AC PDP by Unbalanced Magnetron Sputtering)

  • 김영기;박정태;김규섭;조정수;박정후
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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    • pp.1096-1098
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    • 1999
  • The performance of as plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the optimum preparation conditions of MgO Protecting layer by RF unbalanced magnetron sputtering(UBMS) in surface discharge type AC PDP. The samples prepared with the do bias voltage of -10V showed lower discharge voltage, lower erosion rate as a consequence of ion bombardment, higher optic transparency and higher crack resistance in annealing process than those samples prepared by conventional magnetron sputtering or E-beam eraporation.

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관내연선도체 초전도 자석에서 루프 전류의 형성에 관한 연구 (Investigation on the Loop Current in the CICC Superconducting Magnet)

  • 김석호;정상권
    • 한국초전도ㆍ저온공학회논문지
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    • 제1권1호
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    • pp.33-37
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    • 1999
  • The fast current and field ramp-up experiment was done with the superconducting magnet that is made of three non-insulated strand CICC (Cable-In- Conduit Conductor). The shunt the unbalanced current magnet enabled the unbalanced current measurement which is believed to be associated with the loop current. To explain the generation of the loop current during the current ramp up. the steady-state three strand loop current model was proposed. This model gives an explanation for the relation between the loop current and the twist geometry of the strands. According to this model. The twisr geometry and the surface contact resistance of the strand has significant influence on the generation of the loop current especially in the large superconducting magnet.

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Effect of Bias Voltage on the Micro Discharge Characteristics of MgO Film prepared by Unbalanced Magnetron Sputtering

  • Kim, Young-Kee;Park, Jung-Tea;Park, Cha-Soo;Cho, Jung-Soo;Park, Chung-Hoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.101-102
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    • 2000
  • The performance of ac plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the surface glow discharge characteristics and some physical properties of MgO thin films prepared by reactive RF planar unbalanced magnetron sputtering in connection with ac PDP. The samples prepared with the de bias voltage of -10V showed lower discharge voltage, lower erosion rate by ion bombardment, higher optic transparency and higher crack resistance in annealing process than those samples prepared by conventional magnetron sputtering or E-beam evaporation.

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고속 입자 충격을 도입한 AC PDP의 MgO 보호층 형성에 관한 연구 (Preparation of MgO Protective layer for AC PDP by High Energy Particle Bombardment)

  • 김영기;박정태;고광식;김규섭;조정수;박정후
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권9호
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    • pp.527-532
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    • 2000
  • The performance of ac plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the surface glow discharge characteristics and some physical properties of MgO thin films prepared by reactive RF planar unbalanced magnetron sputtering in connection with ac PDP. The samples prepared with dc bias voltage of -10V showed lower discharge voltage and lower erosion rate byion bombardment than those samples prepared by conventional magnetron sputtering or E-beam evaporation. The main factor that improves the discharge characteristics by bias voltage is considered to be due to the morphology changes or crystal structure of the MgO thin film by ion bombardement during deposition process.

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비대칭 마그네트론 스퍼터링법에 의해 합성된 STR304 스테인리스강 박막에서의 질소와 산소의 첨가 효가 (Effect of $N_2$ and $O_2$ Properties of STS304 Stainless Steel Films Synthesized by Unbalanced Magnetron Sputtering Process)

  • 김광석;이상율;김범석;한전건
    • 한국표면공학회지
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    • 제34권2호
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    • pp.89-96
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    • 2001
  • N- or O-doped STS304 stainless films were synthesized by an unbalanced magnetron sputtering process with various argon and reactive gas ($N_2$, $O_2$) mixtures. These films were examined by scanning electron microscopy (SEM), X-ray diffraction (XRD), Auger electron spectroscopy (AES) and Knoop microhardness tester. The Results from X-ray diffraction (XRD) analysis showed that a STS304 stainless steel film synthesized without reactive gas using a bulk STS304 stainless steel target had a ferrite bcc structure ($\alpha$ phase), while the N-doped STS304 stainless film was consisted of a nitrogen supersaturated fcc structure, which hsa a strong ${\gamma}$(200) phase. In the O-doped films, oxide Phases ($Fe_2$$O_3$ and $Cr_2$$O_3$) were observed from the films synthesized under an excess $O_2$ flow rate of 9sccm. AES analysis showed that nitrogen content in N-doped films increased as the nitrogen flow rate increased. Approximately 43 at.%N in the N-doped film was measured using a nitrogen flow rate of 8sccm. In O-doped film, approximately 15 at.%O was detected using a $O_2$ flow rate of 12sccm. the Knoop microhardness value of N-doped film using a nitrogen flow rate of 8 sccm was measured to be approximately $H_{ k}$ 1200 and this high value could be attributed to the fine grain size and increased residual stress in the N-doped film.

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탈질 조건에서 투과매질 내 미생물 성장에 관한 연구

  • 최영화;오재일;배범한
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.366-369
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    • 2002
  • Subsurface biobarrier technology has potential applications to contain contaminated groundwater and/or to degrade toxic pollutants in groundwater. Most biobarrier studies were conducted under aerobic condition, however there were several obstacles to make aerobic condition. Thus, In this study, we examined biobarrier formation under denitrifying condition by using nitrate as an electron acceptor. Experiments were performed with a sand column inoculated with activated sludge from the nearby WWTP. The substrate medium was pumped to the sand column in an upflow mode. During the low substrate loading rate period, the extent of reduction rate in hydraulic conductivity was found similar throughout the column, and permeability became relatively stable after couple of days. However, during the high substrate loading rate period, the column demonstrated a gradient of permeability reduction, with the greatest reduction in sections nearest the column inlet. Rapid growth of microorganisms near the column inlet resulted in the unbalanced reduction of hydraulic conductivity throughout the sand column. As a result, at this denitrifying condition the thickness of biobarrier could be controlled by adjusting the medium conditions of microbial growth.

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SMOTE와 Light GBM 기반의 불균형 데이터 개선 기법 (Imbalanced Data Improvement Techniques Based on SMOTE and Light GBM)

  • 한영진;조인휘
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제11권12호
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    • pp.445-452
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    • 2022
  • 디지털 세상에서 불균형 데이터에 대한 클래스 분포는 중요한 부분이며 사이버 보안에 큰 의미를 차지한다. 불균형 데이터의 비정상적인 활동을 찾고 문제를 해결해야 한다. 모든 트랜잭션의 패턴을 추적할 수 있는 시스템이 필요하지만, 일반적으로 패턴이 비정상인 불균형 데이터로 기계학습을 하면 소수 계층에 대한 성능은 무시되고 저하되며 예측 모델은 부정확하게 편향될 수 있다. 본 논문에서는 불균형 데이터 세트를 해결하기 위한 접근 방식으로 Synthetic Minority Oversampling Technique(SMOTE)와 Light GBM 알고리즘을 이용하여 추정치를 결합하여 대상 변수를 예측하고 정확도를 향상시켰다. 실험 결과는 Logistic Regression, Decision Tree, KNN, Random Forest, XGBoost 알고리즘과 비교하였다. 정확도, 재현율에서는 성능이 모두 비슷했으나 정밀도에서는 2개의 알고리즘 Random Forest 80.76%, Light GBM 97.16% 성능이 나왔고, F1-score에서는 Random Forest 84.67%, Light GBM 91.96% 성능이 나왔다. 이 실험 결과로 Light GBM은 성능이 5개의 알고리즘과 비교하여 편차없이 비슷하거나 최대 16% 향상됨을 접근 방식으로 확인할 수 있었다.

Plasmid Stability and Cloned-Gene Expression in Continuous Culture of Recombinant Escherichia Coli Under Derepressed Condition

  • Nam, Soo-Wan;Kim, Byung-Kwan;Kim, Jung-Hoe
    • Journal of Microbiology and Biotechnology
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    • 제4권1호
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    • pp.1-6
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    • 1994
  • Continuous culture was carried out with a recombinant Escherichia coli W3110/pCR185, which encodes trp-operon enzymes when the temperature is shifted from $37^{circ}C\;t;42^{\circ}C$. Under derepressed condition of $42^{\circ}C$. plasmlid stability and gene expression were analysed as function of the dilution rate. The stability of plasmid increased with the dilution rate, but maximal levels of gene expression (tryptophan concentration) and plasmid DNA content were obtained at the lowest dilution rate, $0.075\;hr^{-1}$. The plasmid instability, observed at low dilution rates, could be explained by the unbalanced biosynthetic state of the recombinant cell harboring a high copy number of plasmid.

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불평형 마그네트론 스파터링에 의한 AC PDP의 MgO 보호층 형성에 관한 연구 (Preparation of MgO Protective Layer for AC PDP by Unbalanced Magnetron Sputtering)

  • 고광식;김영기;박정태;김언진;조정수;박정후
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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    • pp.142-145
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    • 2000
  • The performance of ac plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the surface glow discharge characteristics and some physical properties of MgO thin films prepared by reactive RF planar unbalanced magnetron sputtering in connection with ac PDP. The samples prepared with the dc bias voltage of -10V showed lower discharge voltage and lower erosion rate by ion bombardment than those samples prepared by conventional magnetron sputtering or E-beam evaporation. The main factor that improves the discharge characteristics by bias voltage is considered to be due to the morphology changes or crystal structure of the MgO thin film by ion bombardment during deposition process.

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범주형 자료에서 순서화된 대립가설 검정을 위한 정확검정의 개발 (Developing of Exact Tests for Order-Restrictions in Categorical Data)

  • 남주선;강승호
    • 응용통계연구
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    • 제26권4호
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    • pp.595-610
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    • 2013
  • 범주형 자료에서 순서화된 대립가설을 검정하는 경우는 의학 사회학 경영학 등 다양한 응용분야에서 발생한다. 이러한 검정 방법은 대부분 대표본이론에 근거하여 개발되었다. 하지만 표본크기가 작거나 표본크기가 매우 불균등한 경우 대표본이론에 근거한 검정방법의 제 1종 오류 확률은 목표로 하는 5%와 멀어지는 경우가 많이 발생한다. 본 논문에서는 범주형 자료에서 순서화된 대립가설을 검정하는 경우 표본크기가 작거나 표본크기가 매우 불균등한 경우에 사용될 수 있는 정확검정방법을 소개하고 이에 대한 검정력 및 정확 p-value를 제시할 것이다.