• 제목/요약/키워드: Output resistance

검색결과 635건 처리시간 0.032초

인버터 저항 점용접 장치의 PWM제어에 관한 연구 (Study on PWM Control in Inverter Resistance Spot Welding)

  • 권효철;최용범
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2006년도 전력전자학술대회 논문집
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    • pp.169-171
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    • 2006
  • Nowadays, inverter welding is risen in spot welding, because can secure productivity. This study made changed output wave form of inverter welding equipment by several forms and measured electric current that pass to the second of transformer for welding. Purpose of study is finding electric current of most suitable form. Also, studied applies PID control in electric current control of inverter resistance weld device and heightens electric current precision.

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등속성(isokinetic) 운동을 이용한 근력 평가 (The Isokinetic Testing of Muscle Strength Evaluation)

  • 김선엽
    • 대한물리치료과학회지
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    • 제1권1호
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    • pp.203-213
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    • 1994
  • As a new concept of resistive exercise, isokinetic exercise was developed during the late 1960's. In isokinetic exercise, the subject works at a fixed speed aganist variable and totally accommodating resistance. During isokinetic exercise the resistance accommodates the external maintains maximum output throughout the full range of motion. The maximum torque during isokinetic movements is a measure of the muscular force applied in dynamic conditions.

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전송선형 초광대역 FM변별기에서 결합 저항기의 오차가 미치는 영향 (Effects of Coupling Resistor Resistance Discrepancy from Characteristic Impedance on Discriminating Characteristics of Super Wide-Band FM Line Discriminator)

  • 이충웅
    • 대한전자공학회논문지
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    • 제7권4호
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    • pp.1-5
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    • 1970
  • 본 논문에서는 전차선형초광대역 FM 변별기의 결합저항식(변별기에 사용된 전송선의 특성임피단스)와의 오차가 ±10%이내일 때 전송선형 FM 변별기의 입력임피단스와 출력파형의 디스토숀에 미치는 영향을 고찰했다.

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저항 점용접기용 변압기 설계를 위한 Interactive 프로그램 개발 (Welding Transformer Interactive Design Program for Resistance Welding)

  • 박승규;장희석
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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    • pp.343-345
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    • 2005
  • In comparison to general purpose step-up/down transformer, welding transformer for resistance spot welding requires strict design criteria. The major significant specifications include duty cycle, arm length and its geometric configuration(window area) as well as various current/voltage conditions and material properties. This interactive program propose new promising procedure for weldling transformer. Users can input design variables and modify in accordance with graphic Output.

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PMN-PZT 세라믹을 사용한 압전트랜스포머 제작과 특성 (Fabrication and Characteristics of Piezoelectric transformer using PMN-PZT)

  • 류주현;손은영;류규현;윤현상;정희승
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.13-20
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    • 1997
  • In this paper, the voltage step-up ratio, efficiency and input impedance of the PMN-PZT cert- mic transformer(PT) were investigated for the variation of resonant frequency according to lead resistance. The output voltage and voltage step-up ratio are increased with the the increase of load resistance. The efficiency of PT showed the maxinum value of 91% at R$_{L}$ of 500k$\Omega$X>

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Swan-Ganz Catheter를 이용한 심폐기능 이상자의 정확한 Cardiac Output 측정 플랫폼 개발 (Cardiac Output Measurement Platform Development Using Swan-Ganz Catheter in Cardiopulmonary Patients with More Accurate)

  • 정용현;나상신;김영길
    • 한국정보통신학회논문지
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    • 제15권7호
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    • pp.1591-1597
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    • 2011
  • 본 논문에서는 심폐기능에 이상이 있는 중환자의 상태를 진단하거나 치료 방향을 정하기 위하여 심박 출량을 측정하는 플랫폼 구현에 관한 연구로써, 센서가 내장된 Swan-Ganz Catheter를 체내에 삽입 후, 생리식염수를 투입하여 생기는 온도변화량을 열희석법을 이용하여 심박출량을 구하는 방법을 사용한다. Swan-Ganz Catheter는 온도센서와 압력센서를 포함하고 있으며 이를 통해 입력되는 센서 값을 보다 세밀하게 수집한다면 심박출량, 전선 및 폐혈관저항, 산소소모량 등을 보다 정확하게 계산해 낼 수가 있으므로 환자의 상태를 보다 정확하게 진단 및 치료가 가능하게 한다.

Constant Output Power Control Methods for Variable-Load Wireless Power Transfer Systems

  • Liu, Xu;Clare, Lindsay;Yuan, Xibo;Wang, Jun;Wang, Chonglin;Li, Jianhua
    • Journal of Power Electronics
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    • 제18권2호
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    • pp.533-546
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    • 2018
  • This study proposes a comprehensive mathematical model that includes coil-system circuit and loss models for power converters in wireless power transfer (WPT) systems. The proposed model helps in understanding the performance of WPT systems in terms of coil-to-coil efficiency, overall efficiency, and output power capacity and facilitates system performance optimization. Three methods to achieve constant output power for variable-load systems are presented based on system performance analysis. An optimal method can be selected for a specific WPT system by comparing the efficiencies of the three methods calculated with the proposed model. A two-coil 1 kW WPT system is built to verify the proposed mathematical model and constant output power control methods. Experimental results show that when the load resistance varies between 5 and $25{\Omega}$, the system output power can be maintained at 1 kW with a maximum error of 6.75% and an average error of 4%. Coil-to-coil and overall efficiencies can be maintained at above 90% and 85%, respectively, with the selected optimal control method.

분극저항에 의한 온라인 부식속도 측정 시스템에 관한 연구 (Study on an On-line Measurement System of Corrosion Rate by Linear Polarization Resistance)

  • 문전수;이재근;이재봉;박필양
    • Corrosion Science and Technology
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    • 제11권4호
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    • pp.135-140
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    • 2012
  • The linear polarization resistance method is one of the widely used techniques for the corrosion rate monitoring in the water circulating systems of plants. The measurement is simple and rapid, so that a continuous on-line monitoring is possible without any shutdown of plants. A 2-electrode polarization corrosion rate measurement system was installed in a laboratory using a data acquisition board and PC. The signal processing parameters were optimized for the accurate corrosion rate measurement, and the polarization resistance was compensated with the solution resistance measured by the high frequency sine wave signal of an output channel. The precision of corrosion rate data was greatly improved by removing the initial noise signals on measuring the polarization resistance.

A Method of Squeegee pressure Optimization for Mass Production Thick Film Heaters Using SPC and Neural Network

  • Luckchonlatee, Chayut;Chaisawat, Ake
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -1
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    • pp.22-25
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    • 2002
  • The Mass production of ceramic heater has encountered with the estimation for the proper parameters of the printing conditions. This paper presents a method to estimate the squeegee pressure. It uses resistance distribution from the trial run with approximate squeegee pressure which comes from statistical process control (SPC). Then, the resistance distribution and its total resistance are input to the backpropagation neural networks that can recognize resistance's distribution patterns. The value of output network derived from the input value can identify to the appropriate squeegee pressure. The experimental results are demonstrated In ensure the efficiency and the reliability of this method with the accuracy 96.75 percent. Indeed, embedded on this method will aid us to reduce the loss from the normal mass production.

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PV 모듈의 손실 저항 성분을 고려한 I-V 출력 모델링에 관한 연구 (Modelling of I-V Characteristics of PV module with resistance variation)

  • 홍종경;정태희;류세환;원창섭;강기환;안형근;한득영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.177-179
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    • 2008
  • This paper, we proposed the theoretical model which includes series resistance $R_s$ and shunt resistance $R_{sh}$ of single-crystalline PV module and used numerical method based on physics. Series resistance $R_s$ was derived from approach for p-n junction diode instead of established form obtained from the simulator with irradiance changes. Electrical output characteristics for PV modules to count the effect of $R_s$ were then studied. Finally simulation results were compared to experimental data leading to good agreement.

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