• 제목/요약/키워드: Hong Dae-Yong

검색결과 790건 처리시간 0.029초

Defective Surface Analysis of Aluminum Bonding Pads for Au Wire Bonding

  • Son, Dong-Ju;Ji, Yong-Joo;Jeon, Yoon-Su;Soh, Dae-Wha;Hong, Sang-Jeen
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.4-4
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    • 2009
  • Surface analysis on defective wire-bonding pads are performed in flash memory assembly. Week wire bonding may cause a significant effect on the final product reliability, and the surface condition of the aluminum bond pads is critical in terms of product reliability. To find out possible week bonding on semiconductor interconnects, ball sheer test (BST) has been performed. On some defective or week bonded pads, we have investigated the surface contents, assuming that the week bonding is induced from the surface conditions. AES and XPS are employed for the quantitative surface analysis on defective dies.

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Study of the Energy Level Alignment of Organic Materials' Planar Junction Prepared by Electrospray Vacuum Deposition

  • 김지훈;홍종암;서재원;권대견;맹민재;박용섭
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.235-235
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    • 2012
  • We investigated the energy levels of valence region at the planar junction of poly (3-hexylthiophene) (P3HT) and C61-butyric acid methylester (PCBM) using ultraviolet photoemission spectroscopy (UPS) with ultra high vacuum. These are the most widely used materials for bulk heterojunction (BHJ) organic solar cells due to their high efficiency. In order to make the planar junction, we carried out the electrospray vacuum deposition (EVD) of PCBM onto spin-coated P3HT in high vacuum conditions (${\sim}10^{-5}-10^{-6}$). The planar junction interface exhibited 0.71 eV for the offset between P3HT HOMO and PCBM LUMO, which is different from the gap (0.85 eV) of individual values and is closer to the open circuit voltage of solar cells fabricated with the same material combination.

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혼합 섬유를 사용한 FRC의 펌프압송 전·후의 공학적 특성 분석 (Engineering Properties of FRC with Combined Fibers Before and After the Pumping)

  • 이제현;박용준;이홍규;김대건;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 추계 학술논문 발표대회
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    • pp.130-131
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    • 2015
  • These days, as the usage of explosive gas is increased, the demand of safety of explosive gas is increased. As a suggestion of protection against the explosive gas, the research on application of fiber-reinforced concrete has been conducted. In this research, therefore, to evaluate the constructability of anti-explosive concrete, the engineering properties of the FRC after pumping is studied.

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무선센서 네트워크를 이용한 가축생육환경정보 실시간 모니터링 시스템 구현 (Implementation of Real-Time Monitoring System for Livestock Growth Environment Information using Wireless Sensor Network)

  • 김영웅;백승현;전용준;이대기;박홍배
    • 대한임베디드공학회논문지
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    • 제7권6호
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    • pp.301-309
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    • 2012
  • In this paper, a real-time monitoring system based on WSN is designed and implemented to monitor livestock growth environment information which includes the temperature, humidity and harmful gases such as $CO_{2},\;CO,\;NH_{3},\;H_{2}S$ and so on. The proposed system consists of the wireless sensor nodes, the monitoring management device, the management server and the user interface program based on PC/Smart phone. To verify the performance of the implemented system, gas measurement experiments are performed in laboratory environment by using the designed wireless sensor nodes. And it is able to estimate the concentration of gases. The implemented system is able to monitor the proposed environmental element information through the developed GUI.

온라인(On-Line)학습이 아동의 수학적 창의력 신장에 미치는 영향 - 초등학교 4학년을 중심으로 (The Influence of using On-Line Learning for improving of Mathematical creativity in elementary school's children)

  • 홍용락;고대곤
    • 한국정보교육학회:학술대회논문집
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    • 한국정보교육학회 2007년도 하계학술대회
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    • pp.123-128
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    • 2007
  • 지식의 양이 기하급수적으로 늘어나고 지식의 창의적인 활용이 세상을 지배하는 지식기반사회에 사는 현대의 아동들에게 무엇보다 중요한 창의력이 오히려 급격히 감소하는 경향을 보이는 이 때, 온라인 학습을 통해 아동들의 수학적 창의력을 신장할 수 있다고 생각하며 수학적 창의력의 요소중 다양한 관점으로 문제를 해결하는 능력을 신장시키기 위해 수학적 능력을 측정할 수 있는 평가도구 프로그램과 측정도구를 이용하여 실시하여 수학적 창의력이 신장됨을 알았다. 그 결과 온라인 학습은 수학적 창의력 신장에 도움을 준다고 할 수 있다.

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네트워크 기반 실시간 제어 시스템을 위한 지연 보상기 개발 (Development of Delay Compensator for Network Based Real-time Control Systems)

  • 김승용;김홍열;김대원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.82-85
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    • 2004
  • This paper proposes the development of delay compensator to minimize performance degradation caused by time delays in network-based real-time control systems. The delay compensator uses the time-stamp method as a direct delay measuring method to measure time delays generated between network nodes. The delay compensator predicts the network time delays of next period in the views point of time delays and minimizes performance degradation from network through considering predicted time delays. Control output considering network time delays is generated by the defuzzification of probable time delays of next period. The time delays considered in the delay compensator are modeled by using a timed Petri net model. The proposed delay prediction mechanism for the delay compensator is evaluated through some simulation tests by measuring deviation of the predicted delays from simulated delays.

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자기증폭기를 이용한 플라이백 컨버터의 제어루프 특성분석 (Analysis on the Control-Loop Characteristics of Flyback Converter with Magnetic Amplifier)

  • 김철진;홍대식;윤신용;김영태
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.213-215
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    • 2003
  • The continuing need for more compact and reliable switching power supplies have aroused a renewed interest in a well founded control technique the Magnetic Amplifier(Magamp). Magamp have some advantages of higher power density simple control circuit, good regulation, high frequency and high performance. The control method with magamp become attractive solutions for high current post regulated output applications. In this study, it is proposed that the magamp technique in flyback converters with multiple output windings. Operation principle of the proposed approach is described and a description of magamp control loop behavior is given first from a circuit level point of view. Then the focus is shifted to look at the same issue from the block diagram point of view. Experimental verifications on 50W multiple output flyback converter are conducted. Simulations and experimental results show that the proposed approach is high efficiency and voltage regulation of the auxiliary output is excellent.

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고주파 진동 측정을 위한 FBG 센서 시스템 개발 및 복합재 시편의 고유진동수 측정 (Development of FBG sensor System for Measuring the High Frequent Vibration of Structures and the Natural Frequency of Composites)

  • 김대현;구본용;김천곤;홍창선;이인
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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    • pp.159-162
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    • 2002
  • We introduce a simple optically passive detection scheme for Bragg grating sensors. This detection scheme is based on two cavity lengths in Fabry-Perot read-out interferometers to produce two quadrature phase shifted signals from the Bragg grating sensor. The passive detection technique is demonstrated by the use of Bragg grating sensors in measuring the dynamic vibrations of the composites.

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퍼지와 유전 알고리즘을 이용한 최적경로 탐색 연구 (A Study on Optimal Path Searching using Fuzzy and GAs)

  • 안대훈;최우경;서재용;김성현;전홍태
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2007년도 춘계학술대회 학술발표 논문집 제17권 제1호
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    • pp.161-164
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    • 2007
  • 우리는 알지 못하는 장소를 찾기 위해 네비게이션을 이용한다. 아직은 단순히 최단거리를 알려주는 네비게이션이 주를 이루고 있다. 하지만 그 길이 최적의 경로가 되는 것은 아니다. 이 논문에서는 이러한 점을 보완하기 위한 새로운 방법을 제시하고 있다. RFID 리더기와 카드를 이용하여 이용자의 출입을 체크함으로써 실시간으로 변하는 각 장소의 인원현황을 알 수 있다. 그리고 거리, 혼잡도, 선호도 등의 몇 가지 정보들을 토대로 퍼지와 유전자 알고리즘을 기반으로 하는 TSP를 이용하여 각각의 이용자 성향에 맞는 최적의 경로를 알 수 있다. 접근성을 높이기 위해 최적의 경로를 보여주는 디스플레이를 장착한 로봇을 이용한다. 다양한 컨텐츠를 포함시키면 더욱 발전한 안내 시스템으로서의 구현이 가능하다.

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