• 제목/요약/키워드: current-effect

검색결과 10,222건 처리시간 0.04초

콘크리트 중의 철근부식 방지를 위한 외부전원법의 적용 (The Application of Impressed Current System for the Corrosion Control of Reinforcing Steel in Concrete)

  • 문한영;김성수;김홍삼
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.197-202
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    • 1997
  • Recently the interest in the reinforcing steel corrosion due to the use of sea-sand and deicing salt, marine environment, and carbonation in RC structures is increasing, therefore the studies on the corrosion control of reinforcing steel in concrete are vigorously proceeding. In this study, from the viewpoint of electrochemical process of steel corrosion in concrete we applied the impressed current system among the cathodic protections to reinforcing steel in concrete and ascertained the protection effect by half-cell potential, corrosion rate, and depolarization.

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New Fabrication Process of Vertical-Type Organic TFTs for High-Current Drivers

  • Kudo, Kazuhiro;Nakamura, Masakazu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.307-309
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    • 2009
  • We have fabricated vertical-type organic transistors (static induction transistors; SITs) with built-in nano-triode arrays formed in parallel by a colloidal-lithography technique. Using this technique, we could fabricate a microstructure in a lateral direction within a large-scale organic device without relying on photolithography. The organic transistor showed low operating voltages, high current output, and large transconductance.

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방전 가공의 기초적 연구 (A Basic Study on Electrical Discharge Machining)

  • 김해종;마대영;김상현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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    • pp.42-45
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    • 1994
  • In this paper, we will report on the effect of the pointed end shape of an electrode, discharge energy, pulse width and discharge current on machining characteristics. The results obtained are as tollows: 1)As the discharge Energy increases, the diameter and the depth of the discharged crater becomes larger and deeper. 2) The discharge energy is not constant during discharge but varies depending on the pointed end shape of th8 electrode. 3) The shape of crater depends on the pulse width and discharge current.

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Risk Management 관점에서 신재생에너지 투자 (Risk Management and Governmental Investment on New & Renewable Energy)

  • 안은영
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.360-363
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    • 2006
  • Regester & Larkin(2005) suggest the issue and risk lifecycle analysis method in risk management, made up of the potential, emerging, current, crisis, and dormant stages. Investment on New & Renewable Energy is meaningful in effect ive risk management for diminishing or reducing the shock of a energy current, at the potential stage. In this study, we survey the risk of traditional fossil fuel projects and develop the risk analysis model for new & renewable energy projects specially geothermal energy resources and gas-hydrate resources.

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Iontophreotic delivery of vitamine-C-2-phosphate

  • Kim, Su-Youn;Oh, Seaung-Youl
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.411.2-411.2
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    • 2002
  • In order to develope an optimum formulation for iontophoretic delivery of vitamine-C-2 phosphate. we have prepared 3 different formulations using hydrophilic polymers, such as poloxamer, carbo pol and HPMC and iontophoretic flux through skin from these hydrogel formulations was carried out. The effect of current density, drug concentration and current profile on flux was investigated. In-vitro flux study was performed at 36.5$^{\circ}C$, using side-by-side diffusion cell. Full-thickness hairless mouse skin was used for this work. (omitted)

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Current Issues in Wind Engineering: A Review

  • Yong Chul Kim
    • 국제초고층학회논문집
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    • 제12권4호
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    • pp.287-297
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    • 2023
  • This paper briefly discusses current issues in wind engineering, including the enhancement of aerodynamic database and AI-assisted design, aerodynamic characteristics of tall buildings with atypical building shapes, application of computation fluid dynamics to wind engineering, evaluation of aerodynamic force coefficients based on a probabilistic method, estimation of tornadic wind speed (JEF scale) and effect of the Ekman Spiral on tall buildings.

제어체적법에 의한 Ar 아크 플라즈마의 특성 계산 (Numerical calculations of characteristics of Argon arc plasma using the control volume method)

  • 김외동;고광철;강형부
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 C
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    • pp.1404-1406
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    • 1995
  • In this paper, argon gas was used for numerical analysis of an arc in a cutting plasma torch driven by constant current. We established nozzle-constricting type torch domain and calculated steady state characteristics of argon arc plasma using the control volume method(CVM). For simplicity, we assumed that the flow field is laminar and the local thermodynamic equilibrium(LTE) prevails in all domain regions. We also neglected cathode-fall and anode-fall effects. Considering magnetic pinch effect and viscosity effect, we solved the momentum equation. Voltage drop in the arc column due to input current was calculated from the temperature field obtained by the energy balance equation.

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일반화 대칭변환을 이용한 원전 증기발생기 전열관 중심인식 비젼 알고리즘 (A vision algorithm for finding the centers of steam generator tubes using the generalized symmetry transform)

  • 장태인;곽귀일
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.1367-1370
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    • 1997
  • This paper presents a vision algorithm for finding the centers of steam generator tubes using the generalized symmetry transform, which is used for ECT(Eddy Current Test) of steam generator tubes in nuclear power plants. The geometrical properties of the image representing steam generator tubes shows that they have amost circular or somewhat elliptic appearances and each tube has strong symmetry about its center. So we apply the generalized symmetry transform to finding centers of steam geneator tubes. But applying the generalized symmetry transform itself without any modification gives difficulties in obtaining the exact centers of steam generator tubes. But applying the generalized symmetry transform itself without any modification gives difficulties in obtaining the exact centers of tubes due to the shadow effect generated by the local light installed inside steam generator. Therefore we make the generalized symmetry transform modified, which uses a modified phase weight function in getting the symmetry magnitude in order to overcome the misleading effect by the local light. The experimental results indicate that the proposed vision algorithm efficiently recongnizes centers of steam generator tubes.

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STT-MRAM Read-circuit with Improved Offset Cancellation

  • Lee, Dong-Gi;Park, Sang-Gyu
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권3호
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    • pp.347-353
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    • 2017
  • We present a STT-MRAM read-circuit which mitigates the performance degradation caused by offsets from device mismatches. In the circuit, a single current source supplies read-current to both the data and the reference cells sequentially eliminating potential mismatches. Furthermore, an offset-free pre-amplification using a capacitor storing the mismatch information is employed to lessen the effect of the comparator offset. The proposed circuit was implemented using a 130-nm CMOS technology and Monte Carlo simulations of the circuit demonstrate its effectiveness in suppressing the effect of device mismatch.

Degradation Pattern of Black phosphorus Field Effect Transistor

  • 이병철;주민규;진준언;이재우;김규태
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.120.1-120.1
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    • 2015
  • We investigate the degradation pattern of Black phosphorus (BP) field effect transistor (FETs) investigated by using an mechanically exfoliated BP that react O2 and water vapor in ambient condition, degradation. The BP FETs was electrically measured every 20 minutes (1cycle) in the air, the total cycle is 100. We show electrical changes with Mobility, On/off ratio, Current and a significant positive shift in the threshold voltage. We extracted the current level at Vgs-Vth = 0, -10, -20 and fitting with Swiss-cheese model. This model suggested that Swiss-cheese model is well fitted with degradation pattern of BP FETs.

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