• Title/Summary/Keyword: Electron Flow

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Effect of Joule Heating Variation on Phonon Heat Flow in Thin Film Transistor (줄 가열 변화에 따른 박막 트랜지스터 내 포논 열 흐름에 대한 수치적 연구)

  • Jin, Jae-Sik;Lee, Joon-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.10
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    • pp.820-826
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    • 2009
  • The anisotropic phonon conductions with varying Joule heating rate of the silicon film in Silicon-on-Insulator devices are examined using the electron-phonon interaction model. It is found that the phonon heat transfer rate at each boundary of Si-layer has a strong dependence on the heating power rate. And the phonon flow decreases when the temperature gradient has a sharp change within extremely short length scales such as phonon mean free path. Thus the heat generated in the hot spot region is removed primarily by heat conduction through Si-layer at the higher Joule heating level and the phonon nonlocality is mainly attributed to lower group velocity phonons as remarkably dissimilar to the case of electrons in laser heated plasmas. To validate these observations the modified phonon nonlocal model considering complete phonon dispersion relations is introduced as a correct form of the conventional theory. We also reveal that the relation between the phonon heat deposition time from the hot spot region and the relaxation time in Si-layer can be used to estimate the intrinsic thermal resistance in the parallel heat flow direction as Joule heating level varies.

A Study on Unit Cell Design for the Performance Enhancement in PEMFC System (PEMFC 시스템의 성능향상을 위한 단위전지 설계에 관한 연구)

  • Kim Hong-Gun;Kim Yoo-Shin;Yang Sung-Mo;Nah Seok-Chan
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.14 no.4
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    • pp.104-109
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    • 2005
  • The catalyst layer design is one of the most important factors to enhance the performance of PEMFC(Proton Exchange Membrane Fuel Cell) system. The hydrophobic and ion conductive type is studied for the MEA(Membrane Electrolyte Assembly). It is found that those have some limitations for performance enhancement when they are used separately. Thus, the dual catalyst type, a mixed model, is developed for the better MEA performance. In the meantime, the design of flow field plate is subsequently carried out in order to give more enhanced output during its operation. The conductivity of flow field plate showed better performance in the case of manufactured by the more compressed process(20MPa) than by the less compressed process(10MPa). The micro-structure of the flow field plate is examined in details using SEM(Scanning Electron Microscope) to analyse the effects on the different compression processes.

Optical and Electrical Properties of Fluorine-Doped Tin Oxide Prepared by Chemical Vapor Deposition at Low Temperature (저온 증착된 불소도핑 주석 산화 박막의 광학적·전기적 특성)

  • Park, Ji Hun;Jeon, Bup Ju
    • Korean Journal of Materials Research
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    • v.23 no.9
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    • pp.517-524
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    • 2013
  • The electrical and optical properties of fluorine-doped tin oxide films grown on polyethylene terephthalate film with a hardness of 3 using electron cyclotron resonance plasma with linear microwave of 2.45 GHz of high ionization energy were investigated. Fluorine-doped tin oxide films with a magnetic field of 875 Gauss and the highest resistance uniformity were obtained. In particular, the magnetic field could be controlled by varying the distribution in electron cyclotron deposition positions. The films were deposited at various gas flow rates of hydrogen and carrier gas of an organometallic source. The surface morphology, electrical resistivity, transmittance, and color in the visible range of the deposited film were examined using SEM, a four-point probe instrument, and a spectrophotometer. The electromagnetic field for electron cyclotron resonance condition was uniformly formed in at a position 16 cm from the center along the Z-axis. The plasma spatial distribution of magnetic current on the roll substrate surface in the film was considerably affected by the electron cyclotron systems. The relative resistance uniformity of electrical properties was obtained in film prepared with a magnetic field in the current range of 180~200A. SEM images showing the surface morphologies of a film deposited on PET with a width of 50 cm revealed that the grains were uniformly distributed with sizes in the range of 2~7 nm. In our experimental range, the electrical resistivity of film was able to observe from $1.0{\times}10^{-2}$ to $1.0{\times}10^{-1}{\Omega}cm$ where optical transmittance at 550 nm was 87~89 %. These properties were depended on the flow rate of the gas, hydrogen and carrier gas of the organometallic source, respectively.

Nutrient Removal Using Fermented Organic Acids Derived from the Primary Sludge in the Intermittent Aeration Activated Sludge Process

  • Weon, Seung-Yeon;Lee, Sang-Il;Lee, Chan-Won
    • Environmental Engineering Research
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    • v.16 no.4
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    • pp.213-218
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    • 2011
  • The two-stage intermittent aeration activated sludge process (IAP) and dynamic-flow intermittent aeration activated sludge process (DFP) were investigated for the nutrient removal of domestic wastewater. Three sets of IAP and one set of DFP were operated. The fermented settled sludge taken from the primary settling tank was added to two IAP and one DFP as an external electron donor, with one IAP, in which an external carbon source was not added, as a control. All the systems were operated at a sludge retention time of 20 days and a hydraulic retention time of 12 hr. A Higher denitrification rate was observed with the fermented settled sludge for the denitrification compared to the process without the addition of the organic source. The result indicates that the fermented acid from the primary domestic sludge has been proved to be an excellent electron donor for denitrification and biological phosphorus removal with IAP and DFP in treating relatively low C/N ratio(Carbon / Nitrogen ratio) wastewater. Phosphate accumulating organisms have a capability of competing with denitrifiers in the presence of volatile organic acids under anoxic conditions.

A Critical Note on the Electric Field in Direct and Alternating Current and Its Consciousness

  • Oh, Hung-Kuk
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2000.11a
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    • pp.98-104
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    • 2000
  • The conventional model did not take momentum conservation into consideration when the electron absorbs and emits the photons. II-ray provides momentum conservations on any directions of the entering photons, and also the electrons have radial momentum conservations and fully elastic bouncing between two atoms, in the new atom model. Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, for examples sexual motion, tidal motion, day and night etc. Because the radius of hydrogen atom's electron orbit is the order of 10$^{-11}$ m and the radia of the nucleons in the nucleus are the order of 10$^{-14}$ m and then the converging $\pi$-gamma rays to the nucleus have so great circular momentum, the electron can not have a circular motion. We can say without doubt that any elementary mass particle can have only linear motion, because of the $\pi$-rays'hindrances, nearthenucleus. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The h v is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. Conventional Concept of Electric Field must be extended in the case of the direct and alternating current. Conventional concept is based on coulomb's force while the electric potential in the direct and alternating current is from Gibb's free energy. And also conventional concept has not any consciousness with human being but the latters has a conscious sensibility. The cell emf is from the kinetic energy of the open $\pi$-rays flow through the conducting wire. The electric potential in alternating current is from that the trans-orbital moving of the induced change of magnetic field in the wire produces flows of open $\pi$-rays, which push the rotating electrons on the orbital and then make the current flow. Human consciousness can induce a resonance with the sensibility of the open $\pi$-rays in the electric measuring equipment. Specially treated acupunctures with Nasucon is for sending an acupunctural effect from one place to another via space by someone's will power.

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On the silicon nitride film formation and characteristic study by chemical vapor deposition method using electron cyclotron resonance plasma (전자 싸이클로트론 공명 플라즈마 화학 증착법에 의한 실리콘 질화막 형성 및 특성 연구)

  • 김용진;김정형;송선규;장홍영
    • Journal of Surface Science and Engineering
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    • v.25 no.6
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    • pp.287-292
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    • 1992
  • Silicon nitride thin film (SiNx) was deposited onto the 3inch silicon wafer using an electron cyclotron resonance (ECR) plasma apparatus. The thin films which were deposited by changing the SiH4N2 gas flow rate ratio at 1.5mTorr without substrate heating were analyzed through the x-ray photo spectroscopy (XPS) and ellipsometer measurements, etc. Silicon nitride thin films prepared by the electron cyclotron resonance plasma chemical vapor deposition method at low substrate temperature (<10$0^{\circ}C$) exhibited excellent physical and electrical properties. The very uniform and good quality silicon nitride thin films were obtained. The characteristics of electron cyclotron resonance plasma were inferred from the analyzed results of the deposited films.

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Application of Hypothetical Quantum Scattering Model for the Design of Novel Electroluminescence Device

  • Jang, Hyo-Weon
    • Bulletin of the Korean Chemical Society
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    • v.23 no.6
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    • pp.807-811
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    • 2002
  • We present a hypothetical quantum scattering model to propose a novel electroluminescence device. Adoping with features of solid state semiconductor LED and exciplex laser, the cathode (electrol incoming potential) and anode(electron outgoing potential) are made to correspond to two 1-dimensional resonance supporting potentials, and the light emitting part to an interaction potential in the intermediate region. When an external voltage is applied, the electron flows into the cathode having small work function. Subsequently in flows via LUMO of the " electron incoming potential" loses kinetic energy emitting a photon, then continues to flow via LUMO of the "electron outgoing potential" unlike the conventional LUMO to HOMO transitions occurring in solid state semiconductor LED. In this model, the photon frequency can be controlled by adijusting the applied voltage. The model hopefully could be realized as partially conjugated hydrocarbon chains.

Study of Electronic Money for Korean Finantial Situation (한국 금융구조형 전자화폐 모델에 대한 연구)

  • 최승우;김용득
    • Proceedings of the IEEK Conference
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    • 2001.06e
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    • pp.173-176
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    • 2001
  • In this treatise information communication indust based change phenomenon of payment system of money explain and study and compare way ago value that use electronic comnunity of the world and presented correct electron money model in real condition of our country. Draw payment way that consider particular situation and korean situation and that wi introduce electron money model of the world and analyze merits and demerits and is money here upon. Electron money introduction of smart card way that support all off-line and on-line that I currency and the nearest topology here direction must is insisting and relate in use of this or presenting value of money flowchart and draw the validity and hangup by introducing electronic mono model who is presenting in Kyong-gi Province and Su-won current and go forward group. Proposed suitable electron money system in Korea situation by proposing money form and model of payment system that can satisfy all this at 1 situation and physical special quality of mon by conclusion and clarify flow of the value.

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Photoinduced Electron Transfer in Molecular Photodiode Consisted of Flavin-Viologen Hetero-LB Films (Flavin-Viologen 복합 LB막으로 구성된 분자광다이오드에서의 광유도 전자전달)

  • 김민진;최정우;정성욱;오세용;이원흥;신동명
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.281-284
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    • 1995
  • A molecular photodiode was fabricated with hetero-Langmuir-Blodgett (LB) film consisting of an electron accepter(A) and sensitizer. N-Allyl-N-[3-propylamido-N\",N\"-야(n-octadecyl)]-4,4-bipyridum Dibromide and 7,8-dimethyl-10-dodecyl isoalloxan-zine were used as A and S units, respectively. By aligning hefter-LB film of A/S units on ITO glass with an aluminium thin film, a molecular photodiode with the structure of Metal/Insulator/Metal(MIM) was constructed. Due to excitation by irradiation with a 460nm monochromatic light source, the photo-induced unidirectional flow of electrons in the MIM device could be achieved and was detected as photocurrents. The direction of energy flow was in accordance with the energy level profile across the LB films. The photo switching function was achieved and the rectifying characteristics was obserbed in the molecular devise.

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A study on the characteristics of electron beam resist with addition of organometallic monomer (유기금속의 첨가에 따른 전자빔 레지스트 특성조사)

  • 박종관;이덕출;우호환;이종태;김보열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.152-155
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    • 1994
  • The purpose of this paper is to develope an electron beam resist by the plasma polymerization. Plasma co-polymerized resist was prepared using an interelectrode gas-flow-type reactor. And then delineated pattern in the resist was developed with gas flow type reactor using Ar and O$_2$ gas as etching gas. We study about the effects of discharge power and mixing rate of the copolymerized thin film. The characteristics of molecular structure of thin film was investigated by FT-lR, DSC and GPC, and then was discussed in relation to its quality as a resist.