• Title/Summary/Keyword: computer center

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Electrical Properties of Mg:Ag/tris-(8-hydroxyquinoline) Aluminum Heterointerface in Organic Light-emitting Devices

  • Choo, D.C.;Im, H.C.;Lee, D.U.;Kim, T.W.;Han, J.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1429-1431
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    • 2005
  • Organic molecular-beam deposition of Mg:Ag thin films with a low Mg concentration on tris (8-hydroxyquinolino) aluminum $(Alq_3)$ layers at room temperature was performed to investigate the feasibility of using Mg:Ag thin films as cathode electrodes in organic light-emitting devices (OLEDs). The effective barrier height of the $Mg:Ag/Alq_3$ heterointerface, determined from current-voltage measurements, was as low as 0.23 eV. These results help improve understanding the electrical properties of the $Mg:Ag/Alq_3$ heterointerfaces in OLEDs.

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A Multimedia Information System Integrating Hypermedia, Information Retrieval, and DBMS Technologies

  • Loh, Woong-Kee;Park, Byung-Kwon;Lee, Sang-Ho;Whang, Kyu-Young
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1996.06b
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    • pp.128-133
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    • 1996
  • In this paper, we describe the design and implementation of a multimedia information system integrating hypermdia, information retrieval, and DBMS technologies. We browse the information space through hypermedia link navigation and also use ad hoc queries for direct retrieval of information from the database. Both the hypermedia and the information retrieval systems are integrated into a database management system (DMBS) so that concurrent edition, update, and retrieval of documents can have the ACID properties of atomicity, consistency, isolation, and durability. We will first explain the architecture of the system and then, describe how the hypermedia system is integrated with information retrieval capability, and finally integrated with DBMS capabilities.

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A Study on the design of stand-alone PV application system (독립형 태양광발전 응용시스템 설계에 관한 연구)

  • Lee Woo-Hee;Lee Mi-Young;Lee Jun-Ha;Lee Hoong-Joo;Kim Seok-Jong
    • Proceedings of the KAIS Fall Conference
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    • 2005.05a
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    • pp.155-158
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    • 2005
  • 소규모 독립형 태양광 발전시스템은 최근 대체에너지에 대한 관심이 증가되면서 다양한 형태의 응용제품이 만들어지고 있다. 그러나 설계방법이 체계화되지 않아 태양전지 및 배터리가 필요이상으로 크게 설계되거나 반대로 너무 작게 설계되어 동작이 불안정해지고 잦은 고장의 원인이 되고 있다. 따라서 본 논문에서는 소규모 독립형 태양광발전 시스템의 설계를 위해 태양전지 및 배터리의 용량산정방법과, 부하특성을 고려하여 안정적인 시스템을 설계하기 위한 방안을 제시하고자 한다.

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Integrate-and-Fire Neuron Circuit and Synaptic Device with Floating Body MOSFETs

  • Kwon, Min-Woo;Kim, Hyungjin;Park, Jungjin;Park, Byung-Gook
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.6
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    • pp.755-759
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    • 2014
  • We propose an integrate-and-fire neuron circuit and synaptic devices with the floating body MOSFETs. The synaptic devices consist of a floating body MOSFET to imitate biological synaptic characteristics. The synaptic learning is performed by hole accumulation. The synaptic device has short-term and long-term memory in a single silicon device. I&F neuron circuit emulate the biological neuron characteristics such as integration, threshold triggering, output generation, and refractory period, using floating body MOSFET. The neuron circuit sends feedback signal to the synaptic transistor for long-term memory.

Characteristics of Polymer Solar Cells Depending on the Thickness of Active Layer

  • Lee, Dong-Gu;Noh, Seung-Uk;Suman, C.K.;Kim, Jun-Young;Lee, Seong-Hoon;Lee, Chang-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1204-1207
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    • 2009
  • We investigated the device performance of bulk heterojunction solar cells depending on the active layer thickness. For the systematic comparison, the polymer solar cells comprising RR-P3HT:PCBM (1:0.8 (wt%:wt%)) blend films with different thickness were characterized by impedance spectroscopy, and J-V measurement in dark and solar simulated illumination. The device with 120 nm thickness of active layer exhibited maximum power conversion efficiency of 3.5 % under AM 1.5 100mW/$cm^2$ illumination condition.

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A Study on Image Segmentation and Tracking based on Intelligent Method (지능기법을 이용한 영상분활 및 물체추적에 관한 연구)

  • Lee, Min-Jung;Hwang, Gi-Hyun;Kim, Jeong-Yoon;Jin, Tae-Seok
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.311-312
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    • 2007
  • This dissertation proposes a global search and a local search method to track the object in real-time. The global search recognizes a target object among the candidate objects through the entire image search, and the local search recognizes and track only the target object through the block search. This dissertation uses the object color and feature information to achieve fast object recognition. Finally we conducted an experiment for the object tracking system based on a pan/tilt structure.

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A Study on DC-DC Converter for The LED Lighting (LED 조명용 DC-DC 컨버터에 관한 연구)

  • Lee Woo-Hee;Lee Mi-Young;Lee Jun-Ha;Lee Hoong-Joo;Kim Seok-Jong
    • Proceedings of the KAIS Fall Conference
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    • 2004.11a
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    • pp.145-147
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    • 2004
  • LED(light emitting diode)는 처리속도, 전력소모, 수명 등에서 큰 장점이 있기 때문에 첨단조명의 광원으로 각광받고 있다. LED는 전원의 변동에 따라 광출력이 변동되므로 일정한 전압, 전류를 유지하는 기술이 필요하다. 따라서 본 논문에서는 LED 조명의 안정된 동작을 위한 전원장치로서 일정한 전압과 전류를 유지해주는 PWM(pulse width modulation) 궤환제어 방식의 부스트 컨버터를 제안하였다.

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Optimum Channel Thickness of Nanowire-FET

  • Go, Hyeong-U;Kim, Jong-Su;Kim, Sin-Geun;Sin, Hyeong-Cheol
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.277-279
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    • 2016
  • Nanowire-FET은 Gate-All-Around (GAA) 구조로 차세대 반도체 소자 구조로 여겨지고 있다. Nanowire-FET은 채널 두께에 따라 $I_D-V_G$ curve에 매우 중요한 영향을 끼친다. 따라서 본 논문은, Edison 시뮬레이션을 이용하여 Nanowire-FET의 Silicon Thickness에 따른 여러 특성을 비교하여 최적 Silicon Thickness에 대해 연구하였다.

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Design and Implementation for Situation-adaptive Automotive Instrument Cluster (상황 적응형 차량 계기 시스템의 설계 및 구현)

  • Bu So-Young;Park Seugn-In;Kim Myoung-Hee
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07b
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    • pp.565-567
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    • 2005
  • 유비쿼터스 컴퓨팅 환경 실현을 위해 차량의 정보화 능력 향상은 필수적이나 이에 관련한 연구는 미비한 편이다. 본 논문은 고성능의 내장형 컴퓨터 및 평판 디스플레이 기술을 자동차 계기 시스템에 적용하여 차량의 컴퓨팅 능력을 증대시키고, 이러한 물리적 환경에 적합한 계기 시스템 설계 모델을 제시한다 제안하는 계기시스템은 디지털 디스플레이의 특성을 살린 레이아웃과 그래픽 효과를 통해 상황에 따라 동적으로 운용된다. 또한 그래픽 인터페이스와 결합한 모바일 기기가 제공되어 사용자가 손쉽게 계기 시스템의 기능을 제어할 수 있다.

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Base Profile Simulation of SiGe Heterojunction Bipolar Transistor for High Frequency Applications (고주파수용 SiGe HBT의 베이스 프로파일 시뮬레이션에 관한 연구)

  • Lee W.H.;Lee J.H.;Park B.S.;Lee H.J.
    • Proceedings of the KAIS Fall Conference
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    • 2004.06a
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    • pp.172-175
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    • 2004
  • This paper analyzes the effects of Ge profiles shape of SiGe heterojunction bipolar transistors (HBT's) for high frequency application. Device simulations using ATLAS/BLAZE for the SiGe HBT with trapezoidal or triangular Ge profile are carried out to optimize the device performance. An HBT with $15\%$ triangular Ge profile shows higher cut-off frequency and DC current gain than that with $19\%$ trapezoidal Ge profile. The cut-off frequency and DC gain are increased from 42GHz to 84GHz and from 200 to 600, respectively. The SiGe HBT has been fabricated using a production CVD reactor.

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