• 제목/요약/키워드: source mechanism

검색결과 1,065건 처리시간 0.035초

Electron Emission Property of Carbon Nanotubes Grown Using Different Source Gases

  • Han, Jae-Hee;Lee, Tae-Young;Yoo, Ji-Beom;Park, Chong-Yun;Jung, Tae-Won;Yu, Se-Gi;Yi, Whi-Kun;Kim, Jong-Min
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.658-661
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    • 2002
  • Chemical species during growth of carbon nanotubes (CNTs) in direct current-plasma enhanced chemical vapor deposition were studied in details using $C_3H_4-NH_3$ and $CO-NH_3$ mixtures through optical emission spectroscopy (OES). In the $C_3H_4-NH_3$ system, the relative intensities of CN (388.3 nm) and CH (431.4 nm) decreased and that of $C_2$ (436 nm) increased, leading to $sp^2$-graphization into the CNT structure, leading to improvement of field emission property of CNTs. In the $CO-NH_3$ system, the trend is completely reversed. Attributing to the atomic oxygen for helping the graphitization of carbon, CNTs could be grown under the flow rate of CO (180 sccm)-$NH_3$ (10 sccm). Through these results, we suggest the growth mechanism in our system.

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Design of a Propagation Wave Type Microrobot for Moving on the Slippery Surface

  • Kim, Eui-Jin;Park, Jong-Hyeon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2072-2077
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    • 2003
  • Animal-like robots are serving an important role as a linkage between biology and engineering. So, in this paper, we aim to develop a biomimetic microrobot that mimics the locomotion mechanism of a gastropod. This microrobot has 3 DOF (x, y translation and rotation), and has small size, unlimited traveling range, high resolution and low cost. Its movement can be made using propagation wave that is generated by the controllable sinusoidal voltage source and piezoelectric effects. This soft motion that can be generated by propagation wave and piezoelectric mechanism would be useful for the motion on the slippery surface. So we modeled the propagation wave mechanism including piezoelectric effect and friction on the contact surface, and could know the velocity of the microrobot is dependent on the driving frequency, input voltage peak, propagation wavelength and surface friction coefficient. With these results we design the microrobot, and accomplish its fabrication and experimentation. The development of this microrobot shall be aimed to design an autonomous moving actuator like animal. Also it can be used from micromanipulation system technology to biology and medicine.

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The Hybrid Knowledge Integration Using the Fuzzy Genetic Algorithm

  • Kim, Myoung-Jong;Ingoo Han;Lee, Kun-Chang
    • 한국데이타베이스학회:학술대회논문집
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    • 한국데이타베이스학회 1999년도 춘계공동학술대회: 지식경영과 지식공학
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    • pp.145-154
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    • 1999
  • An intelligent system embedded with multiple sources of knowledge may provide more robust intelligence with highly ill structured problems than the system with a single source of knowledge. This paper proposes the hybrid knowledge integration mechanism that yields the cooperated knowledge by integrating expert, user, and machine knowledge within the fuzzy logic-driven framework, and then refines it with a genetic algorithm (GA) to enhance the reasoning performance. The proposed knowledge integration mechanism is applied for the prediction of Korea stock price index (KOSPI). Empirical results show that the proposed mechanism can make an intelligent system with the more adaptable and robust intelligence.

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The Hybrid Knowledge Integration Using the Fuzzy Genetic Algorithm

  • Kim, Myoung-Jong;Ingoo Han;Lee, Kun-Chang
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 1999년도 춘계공동학술대회-지식경영과 지식공학
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    • pp.145-154
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    • 1999
  • An intelligent system embedded with multiple sources of knowledge may provide more robust intelligence with highly ill structured problems than the system with a single source of knowledge. This paper proposes th hybrid knowledge integration mechanism that yields the cooperated knowledge by integrating expert, user, and machine knowledge within the fuzzy logic-driven framework, and then refines it with a genetic algorithm (GA) to enhance the reasoning performance. The proposed knowledge integration mechanism is applied for the prediction of Korea stock price index (KOSPI). Empirical results show that the proposed mechanism can make an intelligent system with the more adaptable and robust intelligence.

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발암성 분자와 식품보존제의 광화학 및 열적 반응메카니즘 (Photochemical and Thermal Reaction Mechanism for the Reaction of Carcinogenic Molecules and Food Reservatives)

  • 김민식;채기수;김갑순;성대동
    • 한국식품영양학회지
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    • 제11권3호
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    • pp.267-271
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    • 1998
  • Seyferth 시약인 phenyl(tribromomethyl) mercury 및 diazomethane의 식품보존제인 dehydroacetic acid 및 coumarin과의 발암성과 그 반응기작을 분자 구조적 관점에서 알아보기 위하여 UV/vis 조건과 laser flash photolysis 시켰을 때의 결과는 다음과 같다. 1. Diazomethane과 Phenyl(tribromomethyl) mercury와 dehydroacetic acid와 diazomethane과의 반응은 광화학적 분해 반응에서 생성된 : CBr2와 : CH2 카르벤 중간체의 이탈기 효과에 따라 발암성이 크게 나타났다. 2. laser flash photolysis 상에서 반응시켰을 때 식품보존제의 발암성이 UV/vis 상에서의 photolysis 때보다 크게 나타났다.

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生态补偿的权益量度与机制创新 - 基于云南洱海治理的调查分析 (The Evaluation and Innovation of Ecological Compensation Mechanism based on Practice of Erhai in Yunnan Province)

  • 왕천;두려길;주용진
    • Journal of East Asia Management
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    • 제1권1호
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    • pp.51-64
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    • 2020
  • With the rapid development of Chinese economy, the uncooperativeness between economy and ecological environment has become an obstacle to the progress of the society. Due to the limitations in terms of scale, source of funds and quality, the present ecological compensation mode doesn't realize the planned effects. In this paper, a new framework and mechanism of ecological compensation has been proposed, which could guide the adjustment and improvement of the present policies based on the analysis of implementation to meet the demand for environmental management in Erhai, so as to achieve the co-existence between human beings and nature.

해외 소프트웨어 개발에서의 효과적인 지식이전을 위한 거버넌스 구조에 관한 사례연구 (Governance Structure for Knowledge Transfer in Offshore Software Development)

  • 김경민
    • 한국IT서비스학회지
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    • 제12권2호
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    • pp.13-29
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    • 2013
  • Offshore software development by Korean companies is mainly led by big SI (System Integration) companies. They open Offshore Development Centers (ODC) in developing countries such as India, China, and Vietnam to source software development for their mother companies. Firms with ODC consider transferring knowledge such as business and cultural knowledge as the most complicated yet essential process for the success of offshore development. This study investigates whether the selection of a governance mechanism is related with knowledge transfer and thus the success of offshore development. The results of this study indicate that a hierarchical governance mechanism is appropriate for transferring company-specific, sensitive, complex knowledge in offshore software development.

바이너리 파일 디스크립션 방식을 이용한 ECG 변환 시스템 (ECG Conversion System Using Description Method for Binary Files)

  • 구흥서;정신영
    • 대한전기학회논문지:시스템및제어부문D
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    • 제55권10호
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    • pp.464-470
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    • 2006
  • In this paper, we develop a descriptor based on binary ECG conversion system that supports the conversion of a binary ECG format into XML-based HL7 aECG for the interoperability of ECG. HL7 aECG is a XML based standard for interoperability of ECG waveform. For the conversion of variety of ECG formats, we propose a binary ECG description mechanism. In order to describe binary ECG more efficiently, we develop a XML-based Binary ECG Description (BED) Language. One of the powerful features of using the XML-based ECG Description mechanism is that ECG data can read from various formats without the modification of source code of conversion system, and consequently it reduces conversion system maintenance costs.

화학증착법에 의해 성장된 TiO2박막의 증착기구와 표면형상에 미치는 증착조건의 영향 (Effect of Deposition Conditions on Deposition Mechanism and Surface Morphology of TiO2 Thin Films Deposited by Chemical Vapor Deposition)

  • 황철성;김형준
    • 한국세라믹학회지
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    • 제26권4호
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    • pp.539-549
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    • 1989
  • Polycrystalline TiO2 thin films were deposited on Si and Al2O3 substrates by CVD method. Ethyl titanate, Ti(OC2H5)4, was used as a source material for Ti and O, and Ar was used for carrier gas. In the surface chemical reaction controlled deposition condition, the apparent activation energy of 6.74 Kcal/mole was obtained, and the atomic adsorption on substrate surface was proved to be governed by Rideal-Elley mechanism. In the mass transfer controlled deposition condition, the deposition rate was in a good agreement with the result which was calculated by the simple boundary layer theory. It was also observed that TiO2 thin films show different surface morphology according to the different deposition mechanism, which was fixed by deposition conditions. This phenomenon could be well explained by the surface perturbation theory.

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ATM 망에서 UPC를 이용한 트래픽 제어방법의 성능평가를 위한 시뮬레이터의 개발에 관한 연구 (A Study on the Development of Simulator for Performance Evaluation of Traffic Control using UPC Algorithm in ATM Network)

  • 김문선
    • 한국시뮬레이션학회논문지
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    • 제8권2호
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    • pp.45-56
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    • 1999
  • It is necessary that we should control the traffic to not only efficiently use the rich bandwidth of ATM network but also satisfy the users various requirements for service quality. However, it is very difficult to decide which control mechanism would be applied in real network because there are various types of ATM traffic and traffic control mechanisms. In this paper, a smart simulator is developed ot analyze the performance of a UPC(Usage Parameter Control) mechanism which is a typical traffic control mechanism. The simulator consists of a user interface that supports a menu-driven input form and a simulation program that is executed with the users input parameters. Especially, the simulator establishes more powerful and flexible simulation environment since it supports a more complex simulation applying various source traffic to several different UPC mechanisms at the same time and allows an arbitrary user-defined traffic in addition to some well-known traffic.

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