• 제목/요약/키워드: electro-resistance

검색결과 337건 처리시간 0.027초

Cu/Ni/Au 전극을 이용한 일회용 포도당 센서 개발 (Development of the disposable glucose sensor using Cu/Ni/Au electrode)

  • 이영태;이승로
    • 센서학회지
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    • 제15권5호
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    • pp.352-356
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    • 2006
  • In this paper, we developed enzyme electrode of a new form to improve performance of disposable glucose sensor. We could fabricate electrode of Cu/Ni/Au structure which has very low electrical resistance (0.1 $\Omega$) by sticking copper film to plastic film with laminating method and electro-plated nickle and gold on it. The enzyme electrode was completed by immobilizing enzyme on the fabricated electrode. The fabricated glucose sensor has very quick sensing time as 3 seconds, and excellent reproducibility, fabrication yield as well.

Hydroxy Aromatic Polyimide계 광폴리머 표면을 이용한 광배향 TN 셀의 전기광학 특성 (Electro-optic Characteristics on Photoaligned TN Cell using Photopolymer Based Hydroxy Aromatic Polyimide)

  • 이휘원;황정연;최성호;서동학;서대식
    • 한국전기전자재료학회논문지
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    • 제18권10호
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    • pp.924-928
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    • 2005
  • We synthesized the two types of photoalignment material of high thermal resistance with hydroxyl aromatic polyimide, and studied the liquid crystal (LC) aligning capabilities on the photopolymer layers. Also, electro-optical (EO) performances for the twisted-nematic (TN)-liquid crystal display (LCD) photoaligned with linearly polarized UV exposure were investigated. A good LC alignment with UV exposure on the two types of photopolymer surface can be obtained. The Voltage-transmittance (V-T) curve in the photoaligned TN cell with UV exposure was different from two type. The response time of photoaligned TN cell was measured about 21 ms in two alkyl chain and about 15 ms in four alkyl chain.

고내열성 광폴리머 표면을 이용한 광배향 TN 셀의 전기광학 특성의 연구 (Study of Electro-Optical Characteristics on Photoalignment TN Cell using a High Thermal Photopolymer)

  • 이휘원;황정연;남기형;이면길;서동학;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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    • pp.210-213
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    • 2004
  • We synthesized photoalignment material of high thermal resistance with hydroxyl aromatic polyimide, and studied the liquid crystal (LC) aligning capabilities on the photopolymer layers. Also, electro-optical (EO) performances for the twisted-nematic (TN)-liquid crystal display (LCD) photoaligned with linearly polarized UV exposure were investigated. A good LC alignment with UV exposure on the photopolymer surface can be obtained. However, the low pretilt angles were obtained below $1^{\circ}$. The Voltage-transmittance (V-T) curve without backflow bounce in the photoaligned TN cell with UV exposure was observed. The response time of photoaligned TN cell was measured about 24 ms. Finally, The photoaligned TN cell has few hysteresis, and shows the residual DC voltage that is less.

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Development of a User-Friendly Automatic Control System for Electro-Slag Remelting Process

  • Lim, Tae-Gyoon;Reeu, Chang-Woo;Boo, Kwang-Suk
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.97.5-97
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    • 2001
  • This paper presents development of a user-friendly automatic control system for ESR(Electro-Slag Remelting or Refining) process. It is a second-phase refining one, commonly applied to production of high-purity specialty steel. A primarily refined castingot acts as a consumable electrode and melts by the electric resistance heat generated when high current is induced through a slag bath. The quality of product is evaluated by its chemical composition, purity, micro-structure, uniformity, mechanical property, etc. To meet the standards, above all things, the process should be kept sound and the melt rate should track the optimum profile irrespective of environment variations. Current ESR system is manually operated ...

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하프브릿지형 DC-DC 컨버터의 효율특성 비교에 관한 연구 (A study on comparison of efficiency characteristics for half bridge type DC-DC converters)

  • 이광택;안태영;김성철;유병우;봉상철
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2006년도 전력전자학술대회 논문집
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    • pp.356-359
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    • 2006
  • This paper presented the power losses comparison results with the Active clamp Forward, the Asymmetrical half bridge and the Two transistor forward converters. To estimate for conduction losses in the converters, the steady state analysis regard to parasitic resistance and current effective values for main parts of converters was derived. In addition, the theoretical efficiency for the converters with input voltage 400V, output voltage 12V and maximum power 480W was discussed.

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통전 가압 소결된 Co 소결체의 마멸 거동 (Sliding wear behavior of electro-pressure sintered cobalt)

  • 강석하;김태웅;김용석
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 추계학술대회논문집
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    • pp.218-221
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    • 2004
  • Dry sliding wear behavior of electro-pressure sintered Co, $Co-20\;wt.\%$ CuSn and $Co-20\;wt.\%$ WC composites were investigated. Wear tests of the materials were carried out using a pin-on-disk wear tester at various loads of 10N-100N under a constant sliding speed condition of 0.38m/s against glass ($83\%\;SiO_2$) beads. Sliding distances were varied with a range of $100m{\sim}600m$. A scanning electron microscopy was used to examine morphologies of worn surfaces, cross-sections, and wear debris. The $Co-20\;wt.\%$ WC composite had the highest and the $Co-20\;wt.\%$ CuSn composite showed the lowest wear resistance among the tested materials. All specimens exhibited low friction coefficients ranging from 0.12 to 0.4 at the applied load of 100N.

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Micromechanical 시험법과 전기적 고유저항 측정을 이용한 탄소섬유강화복합재료의 계면 물성과 경화거동에 관한 연구 (Interfacial Properties and Curing Behavior of Carbon Fiber/Epoxy Composites using Micromechanical Techniques and Electrical Resistivity Measurement)

  • 이상일;박종만
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2000년도 추계학술발표대회 논문집
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    • pp.17-21
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    • 2000
  • Logarithmic electrical resistivity of the untreated or thin diameter carbon fiber composite increased suddenly to the infinity when the fiber fracture occurred by tensile electro-micromechanical test, whereas that of the ED or thick fiber composite increased relatively broadly up to the infinity. Electrical resistance of single-carbon fiber composite increased suddenly due to electrical disconnection by the fiber fracture in tensile electro-micromechanical test, whereas that of SFC increased stepwise due to the occurrence of the partial electrical contact with increasing the buckling or overlapping in compressive test. Electrical resistivity measurement can be very useful technique to evaluate interfacial properties and to monitor curing behavior of single-carbon fiber/epoxy composite under tensile/compressive loading.

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보강제 변화에 따른 실리콘 고무의 트래킹 열화 특성에 관한 연구 (A Study on Tracking Degradation Properties of Silicone Rubber due to Reinforcing Agent)

  • 이성일
    • 한국전기전자재료학회논문지
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    • 제27권12호
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    • pp.841-846
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    • 2014
  • It found that the maximum temperature of the arc discharge occurred on the Silicone rubber sample significantly decreased with increasing the reinforcing agent. It was confirmed that the current value decreased with increasing the aluminium trihydrate($Al(OH)_3$) and the current value increased with reducing the primary resistance over time. Regarding these results, may be it is because the degradation due to the electro-conductive carbonization was improved and the properties of dielectric breakdown was reduced by the flame retardant reinforcing agent. It found that the electro-conductive carbonized road has not happened by increasing the flame retardant reinforcing agent. Regarding to the arc discharge, this study show that the arc arising near the lower electrode of sample has disappeared.

정전 분무 공정으로 제조된 Fe-Cr-Al 분말 다공체 금속의 고온 산화 특성에 미치는 기공 크기의 영향 (Effect of Cell Size on the High Temperature Oxidation Properties of Fe-Cr-Al Powder Porous Metal Manufactured by Electro-spray Process)

  • 오재성;공영민;김병기;이기안
    • 한국분말재료학회지
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    • 제21권1호
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    • pp.55-61
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    • 2014
  • Fe-Cr-Al powder porous metal was manufactured by using new electro-spray process. First, ultra-fine fecralloy powders were produced by using the submerged electric wire explosion process. Evenly distributed colloid (0.05~0.5% powders) was dispersed on Polyurethane foam through the electro-spray process. And then degreasing and sintering processes were conduced. In order to examine the effect of cell size ($200{\mu}m$, $450{\mu}m$, $500{\mu}m$) in process, pre-samples were sintered for two hours at temperature of $1450^{\circ}C$, in $H_2$ atmospheres. A 24-hour thermo gravimetric analysis test was conducted at $1000^{\circ}C$ in a 79% $N_2$ + 21% $O_2$ to investigate the high temperature oxidation behavior of powder porous metal. The results of the high temperature oxidation tests showed that oxidation resistance increased with increasing cell size. In the $200{\mu}m$ porous metal with a thinner strut and larger specific surface area, the depletion of the stabilizing elements such as Al and Cr occurred more quickly during the high-temperature oxidation compared with the 450, $500{\mu}m$ porous metals.

Electro-Micromechanical시험법을 이용한 섬유 함침 각에 따른 탄소와 SiC 섬유강화 에폭시 복합재료의 계면 손상 감지능 및 평가 (Interfacial Damage Sensing and Evaluation of Carbon and SiC Fibers/Epoxy Composites with Fiber-Embedded Angle using Electro-Micromechanical Technique)

  • Joung-Man Park;Sang-Il Lee;Jin-Woo Kong;Tae-Wook Kim
    • Composites Research
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    • 제16권2호
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    • pp.68-73
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    • 2003
  • Fragmentation 시험법과 전기저항 측정을 통하여 탄소 및 SiC 섬유강화 에폭시 복합재료의 계면물성과 섬유파단에 대한 전기적 감지능을 연구하였다. 섬유 함침 각이 증가함에 따라서 계면전단강도는 감소하였고, 섬유파단에 의한 전기저항도 값이 무한대로 증가하는 시간은 길어졌다. 높은 함침 각에서 전기저항도의 초기 기울기는 급격히 증가한 반면. 낮은 각에서는 점차적으로 증가하였다. 또한 낮은 함침각의 두 섬유 모두에서 stress whitening pattern을 뚜렷하게 관찰할 수 있었지만, 높은 함침 각에서는 그렇지 못했다. 섬유 함침 각이 감소함에 따라서 섬유 파단 간격과 debonding된 길이는 두 섬유 모두에서 증가하였다. 본 연구에서 사용한 electro-micromechanical 시험법은 전도성 섬유강화 복합재료의 섬유 함침 각에 따른 계면 감지능 측정을 위해서 비파괴적 평가방법으로 실행 가능하였다.