• 제목/요약/키워드: radiation discharge

검색결과 169건 처리시간 0.03초

평면형 구리 - 탄소 전극의 형태별 재기전압 특성 및 파형 패턴에 관한 연구 (Study on Restriking Transient Voltage Characteristics and Waveform Patterns of Planar Copper-Carbon Electrodes using Forms)

  • 임종민;최충석
    • 한국화재소방학회논문지
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    • 제34권4호
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    • pp.1-6
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    • 2020
  • 본 논문은 직렬 아크 방전이 진행될 때의 전압 및 전류 파형을 실시간 측정하였다. 아크 방전의 방사 패턴을 분석한 결과 간헐적인 방전, 아크의 성장, 발열부의 생성, 플룸의 발생, 적열부 형성 순서로 진행되는 것을 알 수 있었다. 직렬 아크 방진이 진행될 때 전류 및 전압 파형은 정현파와 같은 주기성을 나타냈다. 그리고 + 파형에서 - 파형으로 바뀔 때와 - 파형에서 + 파형으로 바뀔 때 파형의 재기전압이 발생하는 것이 확인되었다. 방전이 진행될 때 1 s 동안에 발생하는 열량은 약 0.317 mJ이고, 600 s 동안에 약 190 mJ의 열이 발생하는 것으로 해석되었다. 그리고 단락 지속시간은 약 1.66 ms인 것으로 해석되었으며, 동일한 주기에서 전압 파형은 49.9 V까지 전위가 상승하는 것을 알 수 있었다. 또한, 방전이 진행될 때 전류의 실효치는 약 1.72 A이고, 최대치는 약 2.53 A로 분석되었다. 그리고 전압의 실효치는 약 42.8 V로 계산되었고, 최대치는 약 208 V로 측정되었다.

Successful Treatment of Feline Nasopharyngeal Lymphoma by Hypofractionated Radiation Therapy After Surgical Debulking in a Cat

  • Sumin Kim;Gunha Hwang;Jin-Yoo Kim;Chi-Oh Yun;Seunghwa Lee;Moonyeong Choi;Joong-Hyun Song;Hee Chun Lee;Tae Sung Hwang
    • 한국임상수의학회지
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    • 제41권2호
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    • pp.117-122
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    • 2024
  • A 3-year-old spayed female Russian blue cat was presented for dyspnea, nasal discharge, and stertorous breathing. Plain thoracic radiography revealed no specific findings. Computed tomography (CT) was performed to differentiate upper airway tract disorders. It revealed the presence of an iso-attenuating mass measuring 10.0 × 7.9 × 15.6 mm, with mild homogeneous contrast enhancement occupying the rostral nasopharynx. The mass was surgically debulked via a longitudinal incision in the soft palate. Histopathological and immunohistochemistry analysis of the surgically excised mass revealed CD3-/CD79a+ B cell lymphoma with an incomplete margin. The patient underwent hypofractionated radiation therapy, receiving a total of 36 Gray (Gy) in 6 Gy fractions over a six-week period. A follow-up CT examination was performed after 27 months of irradiation and the patient was confirmed to have achieved a complete response. There were no complications related to irradiation. The patient was alive for 40 months without recurrence. This study suggests that hypofractionated radiation therapy combined with surgical debulking could be considered as a treatment option for feline nasopharyngeal lymphoma.

오존램프를 이용한 한약재 저장 장치의 특성 연구 (A Study of Characteristic of Oriental Herbal Medicine Storage System using Ozone Lamp)

  • 우성훈;이광식
    • 조명전기설비학회논문지
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    • 제21권1호
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    • pp.98-103
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    • 2007
  • 본 연구에서는 한약재 저장장치를 제작하여 한약재 저장 특성을 연구하였다. 저장장치 내에 있는 램프는 '살균 및 오존선을 방사하는 저압 자외선램프(이하, OZ-Lamp)'이다. 방전에서 발생되는 단파장 자외선의 방사 특징을 이용하여, 살균 및 오존 램프의 역할을 수행하고 있는 OZ-Lamp는 한약재 저장을 위한 용도로 사용된다. 본 연구에서는, 한약재의 고품질 유지를 목적으로 한약재 저장 장치의 오존발생 및 전기적 특성을 연구하였으며, 오존처리, 저장에 따른 한약재의 품질 및 성분 특성을 연구하였다.

원통형 캐비티에서 방출되는 방사 전자파 특성 (Characteristics of Radiated Electromagnetic Fields From A Cylindrical Cavity)

  • 김효균;조준호;임동영;김기채
    • 한국정보통신학회논문지
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    • 제20권2호
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    • pp.237-244
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    • 2016
  • 본 논문에서는 주상변압기의 내부 부분방전에 의한 방사 전자파를 예측하기 위해 원통형 캐비티의 구조 및 크기 변화에 따른 1차측, 2차측 전극의 부싱을 통해 방출되는 방사 전자파 특성을 FDTD 법으로 검토하였다. 그 결과, 원통형 캐비티의 구조에서 1차측 및 2차측 부싱에서 방사되는 방사 전자파를 확인할 수 있었다. 원통형 캐비티 외함의 구조에 대한 방사 전자파의 주파수 특성을 검토하고 제작한 원통형 캐비티의 실험을 통해 이론 계산 결과와 비교 검토하였다.

ELECTRONIC SAFING OF A DIODE LASER ARM-FIRE DEVICE

  • Kenneth E. Willis;Suk Tae Chang
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 1995년도 제4회 학술강연회논문집
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    • pp.171-175
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    • 1995
  • Semiconductor diode lasers that can generate one watt or more of optical energy for tens of milliseconds (quasi continuous wave) are now readily available. Several researchers have demonstrated that this power level, when properly coupled, can reliably initiate pyrotechnic mixtures. This means that the initiator containing the pyrotechnic can be protected against inadvertent initiation from electromagnetic radiation or electrostatic discharge by a conducting Faraday cage surrounding the explosive. Only a small dielectric window penetrates the housing of the initiator, thereby eliminating the conductors necessitated by a bridgewire electroexplosive device. The diode laser itself, however, functions at a low voltage (typically 3 volts) and hence is susceptible to inadvertent function from power supply short circuits, electrostatic discharge or induced RF energy. The rocket motor arm-fire device de-scribed in this paper uses a diode laser, but protects it from unintentional function with a Radio Frequency Attenuating Coupler (RFAC).The RFAC, invented by ML Aviation, a UK company, transfers power into a Faraday cage via magnetic flux, thereby protecting the diode, its drive circuit and the pyrotechnic from all electromagnetic and electrostatic hazards. The first production application of a diode laser and RFAC device was by the Korean Agency for Defense Development.

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광섬유 Mach-Zehnder 간섭계를 이용한 부분방전 초음파 검출특성 (Detecting Characteristics of Ultrasonics Generated by Partial Discharge in Insulating Oil Using the Optical Fiber Mach-Zehnder Interferometer)

  • 이상훈;심승환;이광식;김달우
    • 조명전기설비학회논문지
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    • 제17권4호
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    • pp.50-56
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    • 2003
  • 본 논문에서는 유입변압기 진단을 목적으로 부분방전시 발생하는 여러 가지 물리적 화학적 현상중 초음파를 검출하기 위하여 광섬유 Mach-Zehnder 간섭계를 구성하였다. 구성된 광섬유 센서의 초음파 검출 평가 실험을 실시하고, 절연유 중에 배치한 침-평판전극에 교류 고전압을 인가하여 방전시 발생하는 초음파를 측정하고 퓨리에 변환 및 wavelet 변환을 이용한 데이터 분석 결과를 나타냈다.

고속 전원차단 회로 설계 제작 및 측정 (A Design of High-speed Power-off Circuit and Analysis)

  • 정상훈;이남호;조성익
    • 전기학회논문지
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    • 제63권4호
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    • pp.490-494
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    • 2014
  • In this paper, a design of high-speed power-off circuit and analysis. The incidence of high-dose transient radiation into the silicon-based semiconductor element induces the photocurrent due to the creation of electron-hole pairs, which causes the upset phenomenon of active elements or triggers the parasitic thyristor in the element, resulting in latch-up. High speed power-off circuit was designed to prevent burn-out of electronic device caused by Latch-up. The proposed high speed power-off circuit was configured with the darlington transistor and photocoupler so that the power was interrupted and recovered without the need for an additional circuit, in order to improve the existing problem of SCR off when using the thyristor. The discharge speed of the high speed power interruption circuit was measured to be 19 ${\mu}s$ with 10 ${\mu}F$ and 500 ${\Omega}$ load, which was 98% shorter than before (12.8 ms).

Sterilization of Escherichia coli Based on Nd: YAG Resonator with a Pulsed Xenon Flashlamp

  • Kim, Hee-Je;Kim, Dong-Jo;Hong, Ji-Tae;Xu, Guo-Cheng;Lee, Dong-Gil
    • Journal of Electrical Engineering and Technology
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    • 제6권2호
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    • pp.275-279
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    • 2011
  • Sterilization of Escherichia coli (E. coli) is examined using a unique pulsed ultra-violet (UV) elliptical reactor based on Nd:YAG laser resonator, UV radiation from a pulsed xenon flashlamp. The light from the discharge has a broadband emission spectrum extending from the UV to the infrared region with a rich UV contained. Sterilization method by using the UV light is fast, environment-friendly and it does not cause secondary pollution. A Nd:YAG laser resonator having elliptical shape has advantage of concentrating the radiation of the UV light at two foci as the quart sleeve filled with E. coli. The primary objective of this research is to determine the important parameters such as pulse per second (pps), the applied voltage for sterilizing E. coli by using an UV elliptical reactor. From the experiment result, the sterilization effect of UV elliptical reactor is better than that of UV cylindrical reactor, and it can be 99.9% of sterilization at 800V regardless of the pps within 10 minutes.

Derived Limits for Radiological Protection Against ionizing Radiation Based on ICRP-60 Recommendations

  • Jang, Si-Young;Lee, Byung-Soo
    • Nuclear Engineering and Technology
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    • 제32권4호
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    • pp.350-360
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    • 2000
  • In Korea, the dose limits are reduced and are set at the ICRP-60 iimits. However, derived limits tabulated as MPC in air and water are still specified in Notice No.98-12. There are some discrepancies between the primary dose limits and MPCs in air and water. Therefore, in order to accept ICRP-60 recommendations fully, derived limits such as ALI, DAC, ECL for radiological protection against ionizing radiation based on ICRP-60 recommendations were calculated using modified methods of those of 10 CFR part 20, dose limits and committed effective dose coefficients of the Basic Safety Standards of the IAEA. The derived limits in this study were also compared with those prescribed in 10 CFR part 20 as well as MPCs of Notice No. 98-12 in order to analyze the impact of implementing derived limits on nuclear facilities. ECLs in air and water for the control of radioactive discharge into the environment in this study are shown to have lower values (i.e. more conservative), for most part, than those in Notice No. 98-12. Especially, for uranium elements, ECLs in water are approximately a magnitude in the order of two lower than those in Notice No.98-12.

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자외선/적외선 불꽃감지기 소개 및 오동작 방지를 위한 연구 (Introduction of Ultraviolet/Infrared Flame Detector and Method for False Detection Prevention)

  • 임병현;고낙용;황종선;김영민;김종만
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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    • pp.8-11
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    • 2003
  • We propose that when combustible burn with contain carbon, introduce fire detector with sensor of private-use detectable light energy as infrared and ultraviolet in energy of electromagnetic-wave type radiate from flame, method for correct discrimination to resemble fire produce false alarm of detector such as sun light, hot object radiation, are welding. This research using infrared sensor is pyroelectric infrared sensor based black body radiation theory. Ultraviolet sensor is uv Tron using gas multiplication effect to current discharge and photoelectric effect of metal. To have high sensibility and to gain proper output voltage, it has high responsive performance. This research introduced UV/IR compound type flame detector and proposed method of false alarm reduced to resemble fire. The result propres the prevention and extinction of fire technique degree, certificated operation of detector.

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