• 제목/요약/키워드: interface energy

검색결과 1,775건 처리시간 0.03초

IV족 천이금속 질화물과 bcc Fe간 계면 에너지의 제일원리 연구 (A First Principles Calculation of the Coherent Interface Energies between Group IV Transition Metal Nitrides and bcc Iron)

  • 정순효;정우상;변지영
    • 한국재료학회지
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    • 제16권8호
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    • pp.473-478
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    • 2006
  • The coherent interface energies and misfit strain energies of Fe/XN (X=Ti, Zr, Hf) systems were calculated by first principles method. The interface energies in Fe/TiN, Fe/ZrN and Fe/HfN systems were 0.343, 0.114, and 0.030 $J/m^2$, respectively. Influence of bond energy was estimated using the discrete lattice plane/nearest neighbor broken bond(DLP/NNBB) model. It was found that the dependence of interface energy on the type of nitride was closely related to changes of the bond energies between Fe, X and N atoms before and after formation of the Fe/XN interfaces. The misfit strain energies in Fe/TiN, Fe/ZrN, and Fe/HfN systems were 0.239, 1.229, and 0.955 eV per 16 atoms(Fe; 8 atoms and XN; 8 atoms). More misfit strain energy was generated as the difference of lattice parameters between the bulk Fe and the bulk XNs increased.

MNOS 기억소자의 계면상태밀도의 에너지 분포의 결정 (Determination of Energy Distribution of Interface State Density in the MNOS Memory Device)

  • 한태현;강창수;박종하;서광열
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1988년도 추계학술대회 논문집
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    • pp.1-4
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    • 1988
  • The high frequency and quasi-state C-V curves were measured to determine the interface state density in MNOS devices. Berglund method was appropriate for determination of energy distribution of interface state density all over the energy gap. Applying Vg vs Øs relation by Berlund method to comparison-analysis method of the high-frequency and quasi-static C-V curves, we were able to determine the energy distribution by only measured C-V curves without theoretical C-V curves. The interface state density near the conduction band was high at lower temperature than room temperature.

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분자동역학법에 의한 기액계면 분자의 운동특성에 관한 고찰 (A Study on the Characteristics of Molecular Motions on a Liquid-Vapor Interface by a Molecular Dynamics Method)

  • 김혜민;박권하;최현규;최순호
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권1호
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    • pp.34-41
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    • 2005
  • An experimental study of molecular motions on a liquid-vapor interface is limited due to micro-scale characteristics of a system with an angstrom or a nanometer size Therefore, in recent, many studies for micro-scale systems have been conducted by a computer simulation because it is free from experimental limitations. In this study, through the molecular dynamic (MD) method. molecular behavior was clarified on a liquid-vapor interface and a criterion to distinguish between liquid and vapor was suggested by a potential energy and the number of neighboring molecules. At an interface. the potential energy of a molecule was increased but the number of neighboring molecules was decreased when the molecule moved into a vapor region from a liquid region, and vice versa.

The effect of interfacial layer thickness on the interface dipole energy in $O_2$ plasma treated metal/organic interface

  • Kim, Soo-Young;Lee, Jong-Lam
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.115-117
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    • 2009
  • Interface dipole energies between interfacial layers with different thicknesses coated on indium tin oxides (ITOs) and 4,4'-bis[N-(1-naphtyl)-N-phenyl-amino]biphenyl are determined. After $O_2$ plasma treatment on thick-metal (>4 nm) coated ITO, the work function and interface dipole energy increased. In thin-metal (< 2 nm) coated ITO, no change in the interface dipole energy was found though the work function increased. Thus, the $O_2$ plasma treated thin (< 2 nm) interfacial layer reduced the hole injection barrier.

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3차원 동적 다중물리 모델 기반 암세포 증식과정 예측기술 개발 (A STUDY ON CANCER CELL INVASION WITH A THREE-DIMENSIONAL DYNAMIC MULTI-PHYSICS MODEL)

  • 송지환;;김동철
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2010년 춘계학술대회논문집
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    • pp.556-561
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    • 2010
  • This paper proposes a three-dimensional haptotaxis model to simulate the migration of the population of cancer cells. The invasion of the cancer cells relates with the hapto- and the effect of the energy between cells and (ECM). The diffuse interface model is employed, which incorporates haptotaxis mechanism and interface energies. The semi-implicit Fourier spectral scheme is adopted for efficient complications. The simulation results reveal rich dynamics of cancer cells migration.

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강-콘크리트 계면의 계면상수 결정 : 계면상수의 역학적 성질 (Determination of Steel-concrete Interface Parameters: Me chanical Properties of Interface Parameters)

  • 이타;주영태;이용학
    • 콘크리트학회논문집
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    • 제21권6호
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    • pp.781-788
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    • 2009
  • 강-콘크리트 계면의 성질을 대표하는 부착강도, 부착 및 비부착 마찰계수, 부착 및 비부착 마찰계수의 연화영역에서 잔류량의 크기, 모드 I 파괴에너지, 부착 및 비부착 모드 II 파괴에너지, 파괴포락선의 형상계수를 포함한 총 9개 계면상수의 값을 계면거동실험결과와 파괴포락선의 기하학적 형상 및 구성모델을 이용하는 민감도 해석을 통해 결정하였다. 계면의 거동이 계면의 부착상태뿐만 아니라 계면법선방향 응력의 방향과 크기에 따라 매우 민감하게 작용하므로 계면상수 값의 결정에서는 이러한 구속압의 크기와 부착 및 비부착 계면조건을 고려하였다. 강재판 사이에 콘크리트가 타설된 강-콘크리트 계면실험체의 거동해석을 위한 계면유한요소해석을 결정된 계면상수를 적용하여 수행하였으며 실험결과와의 비교를 통해 상수값의 적정성을 검토하였다.

Singular Residual Stresses at Interface of Compound Cylinders

  • Lee, S.S.;Kim, T.H.;Kim, J.G.;Park, K.W.;Hwang, J.K.
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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    • pp.305-310
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    • 1996
  • This paper concerns the cladding residual stresses in a reactor vessel induced during cooling from the manufacturing temperature down to room temperature Finite element results show that very large stress gradients are present at the interface corner and such stress singularity might lead to local yielding or cladding-base metal debonding.

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고전압 비교기를 적용한 스마트 센서용 SECE 에너지 하베스트 인터페이스 회로 설계 (Design of SECE Energy Harvest Interface Circuit with High Voltage Comparator for Smart Sensor)

  • 석인철;이경호;한석붕
    • 한국전자통신학회논문지
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    • 제14권3호
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    • pp.529-536
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    • 2019
  • 스마트 센서 시스템에 압전 에너지 하베스터를 적용하기 위해서는 AC-DC 정류기를 비롯한 에너지 하베스트 인터페이스 회로가 필수적이다. 본 논문에서는 기본적인 회로인 Full Bridge Rectifier(: FBR) 회로와 동기식 압전 에너지 하베스트 인터페이스 회로의 성능을 보드레벨 시뮬레이션으로 비교하였다. 그 결과, 동기식 압전 에너지 하베스트 인터페이스 회로 중 하나인 Synchronous Electric Charge Extraction(: SECE) 회로가 FBR에 비해 출력 전력이 약 4 배 이상 더 컸고, 부하 변동에도 변화가 거의 없었다. 그리고, 출력 전압이 40V 이상인 압전 에너지 하베스터용 SECE 회로에 필수적인 고전압 비교기를 0.35 um BCD 공정으로 설계하였다. 설계한 고전압 비교기를 적용한 SECE 회로는 출력 전력이 FBR 회로 보다 427 % 향상됨을 검증하였다.

Data Management and Communication Networks for Man-Machine Interface System in Korea Advanced Liquid MEtal Reactor : Its Functionality and Design Requirements

  • Cha, Kyung-Ho;Park, Gun-Ok;Suh, Sang-Moon;Kim, Jang-Yeol;Kwon, Kee-Choon
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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    • pp.291-296
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    • 1998
  • The DAta management and Communication NETworks (DACONET), Which it is designed as a subsystem for Man-Machine Interface System of Korea Advanced LIquid MEtal Reactor(KALIMER MMIS) and advanced design concept is approached, is described. The DACONET has its roles of providing the real-time data transmission and communication paths between MMIS systems, providing the quality data for protection, monitoring and control of KALIMER and logging the static and dynamic behavioral data during KALIMER operation. The DACONET is characterised as the distributed real-time system architecture with high performance, Future direction, in which advanced technology is being continually applied to Man-Machine interface System Development of Nuclear Power Plants, will be considered for designing data management and communication networks of KALIMER MMIS

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Small-IoT 환경에서 이기종 네트워크를 활용한 스마트 모바일 단말의 에너지 효율적 실시간 컴퓨팅 기법 (Energy-efficient Real-time Computing by Utilizing Heterogenous Wireless Interfaces of the Smart Mobile Device in Small-IoT Environments)

  • 임성화
    • 반도체디스플레이기술학회지
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    • 제20권3호
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    • pp.108-112
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    • 2021
  • For smart mobile devices, the wireless communication module is one of the hardware modules that consume the most energy. If we can build a multi-channel multi-interface environment using heterogeneous communication modules and operate them dynamically, data transmission performance can be highly improved by increasing the parallelism. Also, because these heterogeneous modules have different data rates, transmission ranges, and power consumption, we can save energy by exploiting a power efficient and low speed wireless interface module to transmit/receive sporadic small data. In this paper, we propose a power efficient data transmission method using heterogeneous communication networks. We also compared the performance of our proposed scheme to a conventional scheme, and proved that our proposed scheme can save energy while guaranteeing reasonable data delivery time.