• Title/Summary/Keyword: self-activation

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High Reliable GaAs HBT with InGaP Ledge Emitter Structure (외부 베이스표면을 에미터 ledge로 포장한 InGaP/GaAs HBT의 신뢰도 향상)

  • 박재홍;박재운
    • Journal of the Korea Society of Computer and Information
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    • v.5 no.4
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    • pp.102-105
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    • 2000
  • The self-aligned AICaAs/GaAs HBTs with the mesa-etched emitter showed severe degradation in current gain under stress. The cause was identified to be due to instability of the surface states on extrinsic base. In this paper the surface states were diminished by the hetero-passivation of the InGaP ledge emitter and the reliability was drastically improved. The activation energy of current gain degradation was extracted to be 1.97eV and MTTF to be 4.8$\times$108 at 14$0^{\circ}C$ which has satisfied MIL standards.

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Stress Relaxation of Poly(methyl acrylate)-Poly(acrylonitrile) Copolymers (Poly(methyl acrylate)-Poly(acrylonitrile) 공중합체의 응력완화)

  • Kim, Nam-Jeong
    • Elastomers and Composites
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    • v.47 no.3
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    • pp.223-230
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    • 2012
  • The rheological parameters of poly(methyl acrylate)-poly(acrylonitrile) copolymers were obtained by applying the experimental stress relaxation curves to the theoretical equation of the Eyring-Halsey non-Newtonian model. The experimentals of stress relaxation were carried out using the tensile tester with the solvent chamber. The determination of rheological parameters was performed from computer calculation. It was observed that the rheological parameters of these copolymer samples are directly related to the self diffusions and viscosities and activation energies of flow segments.

Interaction of the State Authority and Business Structures in the In novative Development of the State Local Governance and Self-Governing in Kazakhstan

  • Karlygash, Mukhtarova;Laura, Ashirbekova
    • East Asian Journal of Business Economics (EAJBE)
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    • v.3 no.3
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    • pp.27-34
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    • 2015
  • The authors consider, that the effectiveness of the government's activity, the improvement of decisions' quality depends on implementation of modern innovative technologies through activation the direct and feedback connection between public authority system and the business -community, through increasing the level of their collaboration by participating in solving main social problems and discu ssing innovative projects (initiative) according questions about socio-economic development of the country, improving the system of the state and local government in the Republic of Kazakhstan.

Development of Educational Programs for PHP using Flash Actionscripts (플래시 액션 스크립트를 이용한 PHP 교육용 프로그램 개발)

  • Kim, Dong-Sik;Lee, Dong-Yeop;Seo, Sam-Jun
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2543-2545
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    • 2003
  • This paper presents a web-based virtual classroom which can be creating efficiencies in the learning process of PHP language. The proposed flash animations which explain the important principles of several topics for PHP language are designed for the learners to easily understand by executing them through simple mouse clicks. The proposed flash animations enables the learners to achieve efficient and interesting self-learning since the learning process is designed to enhance the multimedia capabilities on the basis of various educational technologies. Also, internet-based on-line voice presentation and its related texts together with moving images are synchronized for efficient, language learning process. Through the proposed virtual classroom, the learners will be capable of learning the concepts related to PHP language and its coding. The results of this paper are to allow the implementation of an efficient virtual classroom, and are also expected to make a contributions to the activation of internet-based educational systems.

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Metal-Organic Vapor Phase Epitaxy III. Atomic Layer Epitaxy (MOVPE 단결정층 성장법 III. 원자층 성장법)

  • 정원국
    • Journal of the Korean institute of surface engineering
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    • v.23 no.4
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    • pp.197-207
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    • 1990
  • Atomic layer epitaxy is a relatively new epitaxial pprocess chracterized by the alternate and separate exposure of a susbstrate surface to the reactants contaning the constituent element of a compound semicoductror. The ideal ALE is expected to provide sevral advantageous as petcts for growing complicated heterostrutures such as relativly easy controls of the layer thinkness down to a monolayer and in forming abrupt heterointerfaces though monolayer self-saturatio of the growth. In addition, since ALE is stongly dependent on the surface reaction, the growth can also be controlled by photo-excitation which provides activation can be energies for each step of the reaction paths. The local growth acceleration by photo-excitation can be exploited for growing several device strures on the same wafer, which provides another important practical advantage. The ALE growth of GaAs has advanced to the point the laser opertion has been achieved from AlGs/GaAs quantun well structures where thee active layers were grown by thermal and Ar-laser assisted ALE. The status of the ALE growth of GaAs and other III-V compounds will be reviewed with respect to the growth saturation behavior and the electrical properties of the grown crystals.

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Molecular Layer Deposition of Organic/Inorganic Nanohybrid Dielectrics for OTFTs

  • Lee, Byeong-Hun;Lee, Gwang-Hyeon;Im, Seong-Il;Seong, Myeong-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.56-56
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    • 2010
  • We report a low-temperature fabrication of organic/inorganic nanohybrid dielectrics for organic thin film transistors. The self-assembled organic layers (SAOLs) were grown by repeated sequential adsorptions of C=C-terminated alkylsilane and metal (Al or Ti) hydroxyl with ozone activation, which was called "molecular layer deposition (MLD)". The $TiO_2$ and $Al_2O_3$ inorganic layers were grown by ALD, which relies on sequential saturated surface reactions resulting in the formation of a monolayer in each sequence and is a potentially powerful method for preparing high quality multicomponent superlattices. The MLD method combined with ALD (MLD-ALD) was applied to fabricate SAOLs-$Al_2O_3$-SAOLs-$TiO_2$ nanohybrid superlattices on polymer substrates at relatively low temperature. The MLD method is an ideal fabrication technique for various flexible electronic devices.

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Transition-State Structures for Solvolysis of Methanesulfonyl Chloride

  • 양기열;강금덕;구인선;이익준
    • Bulletin of the Korean Chemical Society
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    • v.18 no.11
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    • pp.1186-1191
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    • 1997
  • Solvolyses of methanesulfonyl chloride (CH3SO2Cl) in water and methanol have been studied theoretically using ab initio self-consistent reaction field (SCRF) molecular orbital method. All stationary structures including transition state on the potential energy surface in solution have been found and compared with the gas phase structures. The overall reaction occurs via a concerted SN2 mechanism with a non-cyclic trigonal bipyramidal transition state, and the activation barrier is lowered significantly in solution. The transition state for the hydrolysis reaction is looser than that for the methanolysis reaction, and this is in accord with the experimental findings that an SN2 type mechanism, which is shifted toward an SN1 process or an SAN process in the hydrolysis and alcoholysis reaction, respectively, takes place. The catalytic role of additional solvent molecules appears to be a purely general-base catalysis based on the linear transition structures. Experimental barrier can be estimated by taking into account the desolvation energy of nucleophile in the reaction of methanesulfonyl chloride with bulk solvent cluster as a nucleophile.

Area selective atomic layer deposition via surface reaction engineering: a review (표면 반응 제어를 통한 영역 선택적 원자층 증착법 연구 동향)

  • Ko, Eun-Chong;Ahn, Ji Sang;Han, Jeong Hwan
    • Journal of the Korean institute of surface engineering
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    • v.55 no.6
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    • pp.328-341
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    • 2022
  • Area selective atomic layer deposition (AS-ALD) is a bottom-up nanopattern fabrication method that can grow the ALD films only on the desired substrate areas without using photolithography and etching processes. Particularly, AS-ALD has attracted great attention in the semiconductor manufacturing process due to its advantage in reducing edge placement error by fabricating self-aligned patterns. In this paper, the basic principles and characteristics of AS-ALD are described. In addition, various approaches for achieving AS-ALD with excellent selectivity were comprehensively reviewed. Finally, the technology development to overcome the selectivity limit of AS-ALD was introduced along with future prospects.

Autophagy in the uterine vessel microenvironment: Balancing vasoactive factors

  • Lim, Hyunjung Jade
    • Clinical and Experimental Reproductive Medicine
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    • v.47 no.4
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    • pp.263-268
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    • 2020
  • Autophagy, which has the literal meaning of self-eating, is a cellular catabolic process executed by arrays of conserved proteins in eukaryotes. Autophagy is dynamically ongoing at a basal level, presumably in all cells, and often carries out distinct functions depending on the cell type. Therefore, although a set of common genes and proteins is involved in this process, the outcome of autophagic activation or deficit requires scrutiny regarding how it affects cells in a specific pathophysiological context. The uterus is a complex organ that carries out multiple tasks under the influence of cyclic changes of ovarian steroid hormones. Several major populations of cells are present in the uterus, and the interactions among them drive complex physiological tasks. Mouse models with autophagic deficits in the uterus are very limited, but provide an initial glimpse at how autophagy plays a distinct role in different uterine tissues. Herein, we review recent research findings on the role of autophagy in the uterine mesenchyme in mouse models.

The Structural relationship among Commitment to Change, Needs of Technology Education Innovation, Communication and Self-Efficacy of Technology Teachers (교육환경 변화에 따른 기술교사의 변화몰입과 기술교육혁신 요구, 커뮤니케이션 및 자기효능감의 구조적 관계 분석)

  • Kim, Yong-lk
    • 대한공업교육학회지
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    • v.36 no.2
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    • pp.111-130
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    • 2011
  • The purpose of this study was to identify a causal relationship among commitment to change, needs of technology education innovation, communication and self-efficacy of technology teachers. A total of 300 copies of questionnaires were used for data analysis except for 117 copies like the one where insincerely responds to any question was found. To ensure the reliability and validity of questions, I performed technical statistics like average, standard deviation, skewness, and kurtosis via PASW 18.0, item-total correlation and the totality, and reliability analysis. I undertook a confirmatory factor analysis via AMOS 7.0 to ensure the validity of items together with a structural analysis to perform a path analysis among variables and assess the suitability of model. The major finding of this study were as follows: First, because fit index of hypothetical model generally met standards in this study, a hypothetical model was judged appropriately. Second, needs of technology education innovation had a positive effect on communication and commitment to change of technology teachers. And, communication among technology teachers had a positive effect on commitment to change of technology teachers. This result means that communication among technology teachers is important to activation of technology education. Third, self-efficacy had a positive effect on commitment to change of technology teachers. This result means that it needs to raise self-efficacy level through teacher education.