• 제목/요약/키워드: Cell current

검색결과 3,988건 처리시간 0.034초

마이크로플라즈마 전류 스위치 및 응용

  • 채결여;김명민;문철희;이상연;이승준
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.433-433
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    • 2010
  • A microplasma current switch (MPCS) for a device operated in a current mode like organic light-emitting diodes (OLEDs), which features matrix addressability and current switching, is presented as well as its architecture and operational principle. The MPCS utilizes the intrinsic memory and conductivity of plasmas to achieve matrix addressability and current switching. We have fabricated a $100\;mm\;{\times}\;100\;mm$ MPCS panel in which its cell pitch is $1080\;{\mu}m\;{\times}\;1080\;{\mu}m$. The matrix addressability and current switching were verified. In addition, the current-voltage (I-V) characteristic of the unit cell was measured when plasmas were ignited. In principle, the scheme of the MPCS is equivalent to that of a double Langmuir probe diagnosing plasma parameters except for their relative dimensions to a plasma volume. Accordingly, the I-V characteristic was analyzed by a double Langmuir probe theory, and the plasma density and electron temperature were estimated from the I-V curve using a collisional double Langmuir probe theory.

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복소임피던스법에 의한 인산형 연료전지용 전해질 매트릭스 특성 (Characteristics of Matrix Retaining Electrolyte in a Phosphoric Acid Fuel Cell Analyzed by A.C. Impedance Spectroscopy)

  • 윤기현;장재혁;허재호;김창수;김태희
    • 한국세라믹학회지
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    • 제32권2호
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    • pp.189-196
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    • 1995
  • Materials retaining electrolyte of a phosphoric acid fuel cell (PAFC) have been prepared with SiC powder to SiC whisker mixing ratios of 1:1, 1:2, 1:3, 1:4, 0:1 by a tape casting method. When 3wt% dispersant (sorbitan monooleate) is added to a matrix, the porosity of the matrix decreases a little while the bubble pressure and area of the matrix increase remarkably in comparison with no dispersant content. Effect of the electrolyte resistance and the polarization resistance on perfomance of a PAFC has been investigated using A.C. impedance spectroscopy. With the increase of whisker content, the electrolyte resistance decreases due to the increase of porosity and acid absorbancy, and the polarization resistance increases due to the increase of surface roughness. The polarization resistance affects current density predominantly at the higher potential than 0.7V becuase the polarization resistance is considrably larger than the electrolyte resistance. Both the electrolyte resistance and the polarization resistance affect current density near 0.7V of the fuel cell operating potential because they have similar values. The electrolyte resistance affects current density predominantly at the lower potential than the fuel cell operating potential because the electrolyte resistance is larger than the polarization resistance.

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Hydrogen Transport through Palladium Foil Placed in Nafion Electrolyte of H2/O2 Fuel Cellsorption

  • Song, Seong-Min;Koo, Il-Gyo;Lee, Woong-Moo
    • 한국수소및신에너지학회논문집
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    • 제12권4호
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    • pp.257-265
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    • 2001
  • Placing a hydrogen conducting, methanol impermeable metallic barrier like palladium (Pd) is a well-known method for preventing methanol crossover through solid polymer electrolyte for direct methanol fuel cells (DMFC). Applying a bias potential between the anode and the barrier can further develop this concept so that the hydrogen transfer rate is enhanced. Since hydrogen diffuses in Pd as atomic form while it moves through nafion electrolyte as ion, it has to be reduced or oxidized whenever it passes the interface formed by Pd and the electrolyte. We performed experiments to measure the hydrogen transport through the Pd membrane placed in Nafion electrolyte of hydrogen/oxygen fuel cell (PEMFC). Applying a bias potential between the hydrogen electrode of the cell and the Pd membrane facilitated the hydrogen passage through the Pd membrane. The results show that the cell current measured with the Pd membrane placed reached almost 40 % the value measured with the cell without Pd membrane. It was found that the current flown through the bias path is only a few percent of the cell current.

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Electrokinetic cell을 이용한 해성점토지반의 개량효과 연구 (Electrokinetic Strengthening of Soft Marine Clays in E/K Cell)

  • 이승원;이영남
    • 한국지반공학회지:지반
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    • 제14권4호
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    • pp.77-90
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    • 1998
  • 본 연구에서는 /K cell(286\times254\times119mm)$을 이용하여 해성점토 지반에서의 electrokinetic 공법에 의한 지반개량효과를 비교 연구하였다. 남해안 해성점토에 대해서 순수 재하시험과 저전압을 이용한 전기삼투시험, 그리고 고전압을 이용한 전기영동시험을 실시한 결과, 저전압 전기삼투에 의한 지반개량 효과가 제일 컸으며, 고전압 전기영동에 의한 지반개량효과는 거의 없는 것으로 나타났다. 또한 전기삼투시험에서는 전류가동시간과 전류밀도가 클수록, 즉 전력소모량이 많을수록 지반 개량효과가 크게 나타났다.

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변형 TEM Cell의 최적 종단 처리를 위한 저항 어레이 망 설계에 관한 연구 (A Study on the Resistor Array Networks for the Optimum Termination of a Modified Large TEM Cell)

  • 이중근;강문수
    • 한국전자파학회논문지
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    • 제7권2호
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    • pp.157-166
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    • 1996
  • 분포 혼합 종단 처리 방식을 채택하고 있는 TEM Cell에 있어서, 내부 도체상의 전류 흐름 및 종단에서의 전류 흐름 해석 방법에 대하여 연구하였다. 회로 해석법을 적용하여 내부 도체 종단부에서의 전류 흐름의 직진성 개선 및 그에 따른 전력 소모를 고려한 최적 종단 저항 네트워크를 설계 하였다. 기존의 각 저항들을 등 간격으로 배치 시켜 구성한 저항 네트워크와 연구결과 제안된 저항 네트워크의 종단 전류 흐름에 대한 수치 해석을 수행하였으며, 두 네트워크를 각각 제작하여 적외선 촬영을 한 결과, 수치 해석 결과와 일치함을 입증하였다.

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전고조파 왜율 분석을 통한 연료전지 스택 고장진단 기술 (Technology of Fuel cell stack fault detection by THDA)

  • 김억수;박현석;강선두;엄정용
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 추계학술대회 초록집
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    • pp.90.1-90.1
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    • 2011
  • This technology is applicable to Electrical vehicle that using Energy from Hydrogen Fueled Cell. Electricity & water is got from chemical reaction between H2 & O2 in stack. This technology is used when fault diagnosis of Fuel cell is needed. It is General method that measure each cell's voltage of stack for fault diagnosis. but, this technology is method of measuring entire voltage of stack. For this reason, fault diagnosis system is simplified and cost of system is lower than previous one. In normal stack condition, characteristic graph of voltage-current has linearity. In fault stack condition, it has non-linearity. we use this characteristic to diagnosis of stack fault. In this technology, Specific frequency current is injected into stack & Stack voltage is measured in response. After that, stack voltage difference is analyzed to diagnosis of stack fault. Presently, Development of current injection module & basic program of THDA is finished. in future we will develop the technology of precise measurement technology about entire stack voltage.

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Development of Bispecific Antibody for Cancer Immunotherapy: Focus on T Cell Engaging Antibody

  • Dain Moon;Nara Tae;Yunji Park;Seung-Woo Lee;Dae Hee Kim
    • IMMUNE NETWORK
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    • 제22권1호
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    • pp.4.1-4.22
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    • 2022
  • In the era of immunotherapeutic control of cancers, many advances in biotechnology, especially in Ab engineering, have provided multiple new candidates as therapeutic immuno-oncology modalities. Bispecific Abs (BsAbs) that recognize 2 different antigens in one molecule are promising drug candidates and have inspired an upsurge in research in both academia and the pharmaceutical industry. Among several BsAbs, T cell engaging BsAb (TCEB), a new class of therapeutic agents designed to simultaneously bind to T cells and tumor cells via tumor cell specific antigens in immunotherapy, is the most promising BsAb. Herein, we are providing an overview of the current status of the development of TCEBs. The diverse formats and characteristics of TCEBs, in addition to the functional mechanisms of BsAbs are discussed. Several aspects of a new TCEB-Blinatumomab-are reviewed, including the current clinical data, challenges of patient treatment, drawbacks regarding toxicities, and resistance of TCEB therapy. Development of the next generation of TCEBs is also discussed in addition to the comparison of TCEB with current chimeric antigen receptor-T therapy.

In-Situ 분석법에 의한 연료전지 특성 연구 (PEMFC Characterization Study by in-situ Analysis Method)

  • 김영민;이종현;임세준;안병기;임태원
    • 한국수소및신에너지학회논문집
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    • 제20권3호
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    • pp.208-215
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    • 2009
  • PEMFC stack power output is needed to be around 100 kW to meet the requirements of automotive application and scaling-up the active area of the stack cells will allow a higher power. In the case of scaling-up the active area of cells, it is difficult to obtain uniform in-plane internal conditions such as temperature, relative humidity and stoichiometry of the feed gas. These ununiformity with the location in the cell would affect both the performance and durability of the stack, so it is important to understand phenomena in the cell for improving them. In this study, the current density, electrochemical resistance and performance distribution measurement was performed to understand the ununiformity in a single cell using in-situ method; (1) Current Density Distribution (CDD) Device and (2) Segmented Cell Fixture. The influence of location of feed gas on the performance of a single cell was experimentally measured and discussed by using a segmented single cell which was composed of 8 compartments. The correlation between the location and performance in a single cell was discussed by these two tools and it was extended between the local characterization and the durability in a MEA by comparing the used cell with a fresh one. It was also studied in terms of electrochemistry by Electrochemical Impedance Spectroscopy.

해상에서의 원유 확산 과정 예측을 위한 격자 기반 이산 사건 및 이산 시간 시뮬레이션 (Cell-based Discrete Event and Discrete Time Simulation for the Prediction of Oil Slick Movement and Spreading in Ocean Environment)

  • 하솔;차주환;구남국;이규열
    • 한국CDE학회논문집
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    • 제17권1호
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    • pp.45-53
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    • 2012
  • In this paper, oil spreading simulation model is proposed for analyzing the oil spreading phenomenon rapidly when the ocean is polluted by the oil from a stranded ship. The space occupied by the ocean is converted into the latticed cell, and the each cell contains the information, such as the quantity of the oil, the temperature of the ocean, and the direction of current and wind. Two states, such as "clean" and "polluted" are defined in the each cell, and the oil in the cell spreads to the neighbor cells by the spreading rules. There are three spreading rules. First, the oil in the certain cell only spreads to the neighbor cells that contain larger oil than the certain cell. Second, the oil evaporates in proportion to the temperature of the ocean at the every time step. Third, the oil spreading property is affected by the direction and the speed of the current and the wind. The oil spreading simulation model of the each cell is defined by using the combined discrete event and discrete time simulation model architecture with the information and the spreading rules in the cell. The oil spreading simulation is performed when the oil of 10,000 kL is polluted in the ocean environment of 300 m by 300 m with various current and wind.

Low Reverse Saturation Current Density of Amorphous Silicon Solar Cell Due to Reduced Thickness of Active Layer

  • Iftiquar, S M;Yi, Junsin
    • Journal of Electrical Engineering and Technology
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    • 제11권4호
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    • pp.939-942
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    • 2016
  • One of the most important characteristic curves of a solar cell is its current density-voltage (J-V) curve under AM1.5G insolation. Solar cell can be considered as a semiconductor diode, so a diode equivalent model was used to estimate its parameters from the J-V curve by numerical simulation. Active layer plays an important role in operation of a solar cell. We investigated the effect thicknesses and defect densities (Nd) of the active layer on the J-V curve. When the active layer thickness was varied (for Nd = 8×1017 cm-3) from 800 nm to 100 nm, the reverse saturation current density (Jo) changed from 3.56×10-5 A/cm2 to 9.62×10-11 A/cm2 and its ideality factor (n) changed from 5.28 to 2.02. For a reduced defect density (Nd = 4×1015 cm-3), the n remained within 1.45≤n≤1.92 for the same thickness range. A small increase in shunt resistance and almost no change in series resistance were observed in these cells. The low reverse saturation current density (Jo = 9.62×10-11 A/cm2) and diode ideality factor (n = 2.02 or 1.45) were observed for amorphous silicon based solar cell with 100 nm thick active layer.