• 제목/요약/키워드: Electrical burn

검색결과 95건 처리시간 0.025초

소결공정에서의 완전 소결점 위치 제어에 관한 연구 (A Study on Burnthrough Point Control in Sintering Process)

  • 이상정;김점근;고명삼;권욱현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1985년도 하계학술회의논문집
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    • pp.55-60
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    • 1985
  • A state-space model of a burn through point control system of an industrial sintering process is derived. The model is then used in designing a self-tuning controller which consists of the receding horizon control law and a least-squares prediction algorithm. By applying this adaptive controller to POSCO sintering process IV, satisfactory expermental results have been obtained. Some of these practical results are presented in this paper.

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항공기용 전원분배장치의 전원개폐에 의한 과도전압 특성 연구 (Study for Transient Voltage Characteristic by Power Switching on Aircraft Electrical Master Box)

  • 서영진;지상용;조지형
    • 항공우주시스템공학회지
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    • 제13권5호
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    • pp.24-31
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    • 2019
  • 본 연구에서는 항공기용 전원분배장치에서 발생한 소손현상의 원인을 분석하고 개선 방안을 제안하였다. 항공기용 전원분배장치는 교류와 직류로 분류하며, 두 장비 사이에 정류기가 존재한다. 전원분배 장치의 전원이 켜지고 꺼질 때 전원 보드내의 커패시터가 소손되었다. 주요 원인은 정류기에 내장되어 있는 인덕턴스로 인해 과도한 전압이 발생했기 때문이다. 고장이 발생 할 수 있는 경우를 분류하였다. 그리고 그에 따른 영향성을 분석하였으며, 실험적인 방법을 통해서 해결책을 수립하였다.

A Study on the Transformer Design considering the Inrush Current Reduction in the Arc Welding Machine

  • Kim, In-Gun;Liu, Huai-Cong;Cho, Su-Yeon;Lee, Ju
    • Journal of Magnetics
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    • 제21권3호
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    • pp.374-378
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    • 2016
  • The transformer used in an inverter type arc welding machine is designed to use high frequency in order to reduce its size and cost. Also, selecting core materials that fit frequency is important because core loss increases in a high frequency band. An inrush current can occur in the primary coil of transformer during arc welding and this inrush current can cause IGBT, the switching element, to burn out. The transformer design was carried out in $A_P$ method and amorphous core was used to reduce the size of transformer. In addition, sheet coil was used for primary winding and secondary winding coil considering the skin effect. This paper designed the transformer core with an air gap to prevent IGBT burnout due to the inrush current during welding and proposed the optimum air gap length.

커패시터용 MPPF의 교류전압 인가시 전기적 특성 (The Electrical Characteristics of MPPF for Capacitor Applications under AC condition)

  • 정종욱;곽희로;박중신
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2000년도 학술대회논문집
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    • pp.155-159
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    • 2000
  • This paper describes the self healing characteristics of metalized polypropylene film(MPPF) under ac condition. PDs were generally observed at relatively low voltage, and the PDIVs were differently varied depending on the number of pre-self healing due to void defects. Several pre-self healing events took place at lower voltage than the critical breakdown voltage of PPF. Self healing mainly occurred at pin tips, wrinkle sides, and cross points of wrinkles. The applied voltage at self healing was increased with PPF thickness. The burn out area at self healing was also increased with the applied voltage and PPF thickness. The peak currents in a grounding conductor at self healing was also increased with the applied voltage.

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Expediting venous drainage in large anterolateral thigh flaps for scalp electrical burns in India: two case reports on the use of primary vein grafts for second vein anastomosis

  • Jyotica Jagadish Chawaria;Parvati Ravula;Nazia Tabassum;Srikanth Rangachari
    • Journal of Trauma and Injury
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    • 제36권4호
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    • pp.404-410
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    • 2023
  • Large scalp defects resulting from high-voltage electrical burns require free flaps, preferably skin, to permit optimal coverage and enable future or simultaneous cranial vault reconstruction. The anterolateral thigh permits the harvest of a large area of skin supplied by a reliable perforator. The superficial temporal vessels offer the proximate choice of recipient vessels to enable adequate reach and coverage. The lack of a second vein at this site implies the inability to perform a second venous anastomosis; however, this obstacle can be overcome by using an interposition vein graft, to the neck veins primarily. This assures adequate venous drainage and complete flap survival.

잎상추 수경재배에서 근권 pH와 EC가 무기이온흡수, 광합성, 증산량 및 생육에 미치는 영향 (Effects of pH Level and Electrical Conductivity on Growth, Nutrient Absorption, Transpiration and $CO_2$ assimilation of Leaf Lettuce in Hydroponics)

  • 박미희;심미영;이용범
    • 생물환경조절학회지
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    • 제8권2호
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    • pp.115-124
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    • 1999
  • 본 실험은 상추 수경재배시 지하부 환경요인이 상추의 생육에 미치는 영향을 바탕으로 식물공장에서 활용가능성이 큰 상추의 최적 근권환경을 알아보고자 수행하였다 근권부 환경조건으로는 배양액의 pH와 U를 각각 여러 가지 수준으로 실험하였다. pH 3.0을 제외한 pH 4.0~8.0에서 가시적인 생리장해 없이 양호한 생육을 나타냈으나 광합성, 증산량 및 무기이곤 흡수를 고려한 상추의 최적 배양액 pH는 pH 5.5~6.0였다. 배양액의 전기전도도는 0.8~3.6 mS.$cm^{-1}$ /로 처리하였을 때, 고농도에서는 Ca결핍으로 인한 잎끝마름증이 나타나 품질이 저하되었고 생육과 광합성이 높은 EC 1.2~l.6mS.$cm^{-1}$ /가 최적인 것으로 나타났다. 이런 결과는 상추 식물공장에서 상추의 주년생산, 공장적 대량생산 및 청정생산 등의 효율적인 재배를 하는데 기여 할 수 있을 것으로 보인다.

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즉발감마선에 의한 상용전자소자의 피해현상분석 연구 (The Study of Transient Radiation Effects on Commercial Electronic Devices)

  • 오승찬;이남호;이흥호
    • 전기학회논문지
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    • 제61권10호
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    • pp.1448-1453
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    • 2012
  • In this study, we carried out transient radiation test for identify failure situation by a transient radiation effect on operational amplifier devices. This experiments were carried out using a 60 MeV electron beam pulse of the LINAC(Linear Accelerator) facility in the Pohang Accelerator Laboratory. In this test, we has found that a serious failure as a burn-out effect due to overcurrent on the partial electronic devices.

자외선 센서를 이용한 화재감지기 응용 회로 설계 (Circuit Design of Ultraviolet Flame-Sensor for Fire-Fighting Appliances)

  • 김영민;김종만
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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    • pp.1-5
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    • 2008
  • In this paper, we proposed that when combustible burn with ultraviolet radiation, introduce fire detector with sensor of private-use detectable light energy as ultraviolet in energy of electromagnetic-wave type radiate from flame. This research using ultraviolet flame sensor is pyro-electric ultraviolet sensor based black body radiation theory. To have high sensibility and to gain proper output voltage, it has high responsive performance. This research introduced UV flame detector and proposed method of false alarm reduced to resemble fire. the result proposed the prevention and extinction of fire technique degree, certificated operation of detector.

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병원건물 분산에너지시스템 도입에 따른 경제성분석 (The Basic Study on Economic Evaluation of Distributed Energy System Installed in Hospital)

  • 홍원표;김병수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1136_1138
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    • 2009
  • This paper gives a basic Energy performance data of micro gas turbine and Renewable Energy(BIPV and Solar Collector System) installed in Hospital Building. The efficiency of solar collector and BIPV system was 30%, 10% individually, and lower than micro gas turbines. Micro gas turbines are small gas turbines that burn gaseous and liquid fuels to produce a high-energy exhaust gas and to generate the electrical power. Recently the size range for micro gas turbines is form 30 to 500kW and power-only generation or in combined heat and power(CHP) systems. If micro gas turbine was operated only for electric energy, the efficiency was about 30%, but for combined heat and power, the efficiency was about 90%. Finally, installed in large hospital, Micro gas turbine system was operated to CHP mode, was high-efficiency system than Solar collector and BIPV system.

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가로등 전용 누전 개폐기의 차단효과에 대한 고찰 (Characteristics of Street Lamp Controller with Earth Leakage Contactor)

  • 이성재;신재식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.283-283
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    • 2010
  • Smart street light controller is a product with advance micro controller base for energy saving in conventional street lighting systems. Intelligent Street light controller are specially developed for automation and energy saving in conventional street light systems and lighting systems. It is so designed that it operates on sunrise & sun set timings according to longitude of particular location with facilitate to set month wise civil twilight timings to cope up with all seasons. Dimming (Power down) mode selection switch on/off at fixed times with relay or contactor. Night dimming, staggering and intelligent control reduces burn hours and increases the lifetime of lamps with about 30% and low annual operating cost type base are among the most inexpensive wireless technologies available. Low initial costs As PLC wireless, there is no need to establish cable connection.

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