• 제목/요약/키워드: application layer

검색결과 2,948건 처리시간 0.028초

Layer-by-Layer 자기조립현상을 이용한 다층초박막의 제조와 응용 (Fabrication of Ultrathin Multilayer Films Using Layer-by-Layer Self-Assembly Method and Their Application)

  • 차국헌;조진한
    • 한국고분자학회지:고분자과학과기술
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    • 제15권3호
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    • pp.260-273
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    • 2004
  • Layer-by-layer 자기조립방법 (self-assembly method) 이라고 불리는 담지자기조립방법 (dip self-assembly method)을 이용한 다층초박막은 다양한 전기적, 자기적 성질을 갖는 물질뿐만 아니라 DNA 또는 효소 (enzyme)같은 바이오 물질들을 기판의 크기나 형태에 관계없이 각각의 층에 나노미터 두께로 삽입시킬 수 있음에 따라서 초박막안에 우리가 원하는 특정 성질을 부여할 수 있다. (중략)

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Cu와 Si 사이에서 확산방지막으로 사용하기 위한 ZrN 층의 연구 (A study on ZrN layer as a diffusion barrier between Cu and Si)

  • 김창조;김좌연;윤의중;이재갑
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
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    • pp.21-24
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    • 1998
  • The properties of ZrN layer deposited by Sputtering system have been investigated in the application of diffusion barrier layer to copper. ZrN layer exhibited a excellent barrier property up to $700^{\circ}$ and higher resistivity. If an excess $O_2$is protected during the process of ZrN deposition, ZrN layer will be possible to use a diffusion barrier layer to copper.

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APP-MAC-PHY Cross-Layer Video Streaming Technique over Wireless Channels

  • Park, Jaeyoung;Kim, Jaekwon
    • 한국통신학회논문지
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    • 제39A권7호
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    • pp.398-400
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    • 2014
  • In this letter, we propose a cross-layer technique jointly considering modulation coding schemes (MCSs) of medium access control (MAC) layer, source significance information (SSI) and error concealment unit of application (APP) layer, and channel quality information (CQI) of physical (PHY) layer. We demonstrate the improved video quality by the proposed technique when H.264 videos are streamed over Rayleigh fading wireless channels.

Recent Progress in Layer-by-layer Assembly of Nanomaterials for Electrochemical Energy Storage Applications

  • Kim, Sung Yeol
    • 전기화학회지
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    • 제17권3호
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    • pp.139-148
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    • 2014
  • Electrochemical energy-storage devices such as batteries and supercapacitors are important components in emerging portable electronic device, electric vehicle, and clean energy storage and supply technologies. This review describes recent progress in the development of nanostructured electrodes, the main component of the electrochemical energy-storage device, prepared by layer-by-layer (LbL) electrostatic assembly. Major advantages associated with, and challenges to, the fabrication of LbL electrodes, as well as the future outlook for expanding the application of LbL techniques, are discussed.

EDTA의 세정시간에 따른 근관 내 smear layer의 제거효과에 관한 연구 (TIME-DEPENDENT EFFECTS OF EDTA APPLICATION ON REMOVAL OF SMEAR LAYER IN THE ROOT CANAL SYSTEM)

  • 이자경;박상혁;최기운
    • Restorative Dentistry and Endodontics
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    • 제31권3호
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    • pp.169-178
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    • 2006
  • 본 연구는 EDTA용액의 적용 시간에 따른 도말층의 제거 효과를 비교하여 EDTA용액의 최적 적용 시간을 알고자 시행되었다. 단근치 35개를 NaOCl 용액 하에서 근관 형성 후 대조군은 NaOCl 용액 5 ml로 2분간, 실험군은 30초군, 1분군, 2분군으로 세분하여 17% EDTA 용액 5 ml로 각각 30초, 1분, 2분간 세정하였다. 세정이 끝난 치근의 도말층 제거 정도와 상아 세관의 erosion 정도를 주사전자현미경을 이용하여 관찰한 결과는 다음과 같다. 1. 대조군: 도말층이 전혀 제거되지 않았다. 2. 실험군 1) 중간$\frac{1}{3}$: 세 군 모두에서 도말층이 거의 완전히 제거되었고, EDTA적용 시간이 증가할수록 erosion발생 빈도가 증가하였다. 2) 치근단$\frac{1}{3}$: 2분군이 다른 두 군에 비해 도말층 제거 정도가 우수하였다. 따라서 erosion 발생을 최소화면서 도말층을 효과적으로 제거하기 위해서는 17% EDTA 용액을 2분간 사용하는 것이 적절한 것으로 사료된다.

CAN내장 휴머노이드 로봇에 대한 응용층 설계 (An Application Layer Design for Humanoid Robot in the Controller Area Network(CAN))

  • 구자봉;허욱열
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.258-260
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    • 2004
  • The Controller Area Network (CAN) is being widely used in real-time control applications such as automobiles, aircraft, and automated factories. Unfortunately, CAN, in its current form, is not able to either share out the system bandwidth among the different devices fairly or to grant an upper bound on the transmission times experienced by the nodes connected to the communication medium as it happens, for instance, in the token-based networks. In this paper, we present An Application Layer Design for Humanoid Robot in the CAN. Besides introducing the new algorithm, this paper also presents some performance figures obtained using a specially developed software simulator and experimentation for composition of CAN which uses JTAG mode of a parallel debugging., while the behavior of the new algorithm is compared with the traditional CAN systems. in order to see how effective they are.

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A Simple and Efficient One-to-Many Large File Distribution Method Exploiting Asynchronous Joins

  • Lee, Soo-Jeon;Kang, Kyung-Ran;Lee, Dong-Man;Kim, Jae-Hoon
    • ETRI Journal
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    • 제28권6호
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    • pp.709-720
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    • 2006
  • In this paper, we suggest a simple and efficient multiple-forwarder-based file distribution method which can work with a tree-based application layer multicast. Existing multiple-forwarder approaches require high control overhead. The proposed method exploits the assumption that receivers join a session at different times. In tree-based application layer multicast, a set of data packets is delivered from its parent after a receiver has joined but before the next receiver joins without overlapping that of other receivers. The proposed method selects forwarders from among the preceding receivers and the forwarder forwards data packets from the non-overlapping data packet set. Three variations of forwarder selection algorithms are proposed. The impact of the proposed algorithms is evaluated using numerical analysis. A performance evaluation using PlanetLab, a global area overlay testbed, shows that the proposed method enhances throughput while maintaining the data packet duplication ratio and control overhead significantly lower than the existing method, Bullet.

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CMS: Application Layer Cooperative Congestion Control for Safety Messages in Vehicular Networks

  • Lee, Kyu-haeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권3호
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    • pp.1152-1167
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    • 2018
  • In this paper, I propose an application layer cooperative congestion control scheme for safety message broadcast in vehicular networks, called CMS, that adaptively controls a vehicle's safety message rate and transmit timing based on the channel congestion state. Motivated by the fact that all vehicles should transmit and receive an application layer safety message in a periodic manner, I directly exploit the message itself as a means of estimating the channel congestion state. In particular, vehicles can determine wider network conditions by appending their local channel estimation result onto safety message transmissions and sharing them with each other. In result CMS realizes cooperative congestion control without any modification of the existing MAC protocol. I present extensive NS-3 simulation results which show that CMS outperforms conventional congestion control schemes in terms of the packet collision rate and throughput, especially in a high-density traffic environment.

다목적 클러스터링 시스템을 위한 고속 메시징 계층 구현 (Implementation of High Performance Messaging Layer for Multi-purpose Clustering System)

  • 박준희;문경덕;김태근;조기환
    • 한국정보처리학회논문지
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    • 제7권3호
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    • pp.909-922
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    • 2000
  • High sped messaging layer for application's feeling of low level network performance is needed by Clustering System based on high speed network fabrics. It should have the mechanism to directly pass messages between network card and application space, and provide flexible affodabilities for many diverse applications. In this paper, CROWN (Clustering Resources On Workstations' Network) which is designed and implemented for multi-purpose clustering system will be introduced briefly, and CLCP(CROWN Lean Communication Primitives)which is the high speed messaging layer for CROWN will be followed. CLCP consists of a firmware for controlling Myrinet card, device drier, and user libraries. CLCP supports various application domains as a result of pooling and interrupt receive mechanism. In case of polling based receive, 8 bytes short message, and no other process, CLCP has 262 micro-second response time between two nodes, and IM bytes large message, it shows 442Mbps bandwidth.

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새로운 전송률 적응기법을 통한 효율적인 비디오 스트림 전송 메커니즘 (Efficient Video Streaming Mechanism through a New Rate Adaptation Scheme)

  • 이선헌;정광수
    • 방송공학회논문지
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    • 제14권1호
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    • pp.44-58
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    • 2009
  • 무선랜 환경에서 효율적인 비디오 스트리밍 서비스를 제공하기 위해서, 네트워크 하위 계층은 무선 채널의 상태 변화에 적응적으로 전송모드를 조절할 수 있어야 하며, 상위 계층의 비디오 스트리밍 응용은 선택된 전송모드에 따라 적절히 서비스되는 비디오 스트림의 품질을 조절할 수 있어야 한다. 상대적으로 높은 대역폭을 요구하는 비디오 스트리밍 응용을 위해서 본 논문에서는 새로운 전송률 적응기법을 포함하는 크로스레이어 디자인을 제안한다. 제안하는 새로운 전송률 적응기법은 연속적인 프레임 전송을 통해 무선 채널의 대역폭을 보다 효율적으로 사용하며, 전송모드별 Goodput 계산을 통해 최적의 성능을 보이는 전송모드를 선택하게 된다. 선택된 전송모드를 기반으로 무선 채널의 한계 대역폭을 계산하며, 이를 상위 계층의 비디오 스트리밍 응용에 알려줌으로써 전송되는 비디오 스트림의 품질을 조절하게 된다. 즉, 네트워크 하위 계층과 상위 계층과의 연동을 통해 무선랜 환경에서 보다 효율적인 비디오 스트리밍 서비스를 제공할 수 있게 된다. 시뮬레이션을 이용한 성능 검증을 통해 제안하는 새로운 전송률 적응기법의 성능 향상을 검증하였으며 크로스레이어 디자인을 통해 비디오 스트리밍 서비스의 품질을 향상시킬 수 있음을 확인하였다.