• 제목/요약/키워드: Photo multiplier tube

검색결과 27건 처리시간 0.021초

Optical Ozone Monitor Using UV Source

  • Chung, Wan-Young
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2003년도 ICCAS
    • /
    • pp.49-52
    • /
    • 2003
  • Two types of ozone monitors using UV absorption method were tried in consideration of cost of the monitor and precision in measuring. The high concentration ozone monitor for high concentration real time ozone monitoring from ozone generator was composed of a low pressure mercury lamp as UV source, a photo multiplier tube as UV detector and signal processing unit for the most part. This structure could be very useful for low price high concentration ozone monitor due to simple system structure and fairly good monitoring characteristics. The developed system showed good linear output characteristics to ozone in the measuring concentration range of 0.05 and 2 wt.%. For accuracy ambient ozone monitoring in ambient in ppm level, the system composed of a high power pulsed xenon lamp as UV source, an optical spectrometer with a high sensitivity linear CCD array as UV detector and signal processing unit in brief speaking was proposed our study for the first time in the world. The developed system showed good linearity and sensitivity in relative low measuring range between 10ppm and 10,000ppm, and showed some feasibility of high resolution ozone monitor using CCD array as photodetector.

  • PDF

7개 경혈부위에서의 생물광자(Biophoton) 방출량 비교 (Comparing Biophoton Emissions from Seven Acupuncture Points)

  • 김동훈;신광문;정현희;박상현;양준모;소경순;이성묵;소광섭
    • 대한예방한의학회지
    • /
    • 제8권2호
    • /
    • pp.45-53
    • /
    • 2004
  • We measured biophoton emissions from seven acupuncture points of eight healthy subjects. The measured points are the Yintang, the $Danch{\bar{u}}$, the Shinketsu, the left and right $R{\bar{o}}ky{\bar{u}}$ and the left and right Yaotongwue of hands. The photo multiplier tube (H-610805s, Hamamatsu, Japan) has spectral range between 300nm and 650nm. Significantly low emission rate was observed at the Shinketsu where the rate was $3.7\;{\pm}\;1.8\;cps$. On the average the highest emission was from the Yaotongxue points where the rate was $11.3\;{\pm}\;5.4$. The high correlation between the left and right hands, and the low correlation between different points are consistent with previous reports.

  • PDF

가스차단기내 아크의 복사에너지 측정에 관한 연구 (Study on the Measurement of Radiation Energy of the Arc in GCBs)

  • 송기동;오연호;정진교;조용성
    • 전기학회논문지
    • /
    • 제56권12호
    • /
    • pp.2122-2126
    • /
    • 2007
  • A special PM-Tube(Photo Multiplier Tube) that is using the photoelectric effect has been designed and manufactured to measure the radiation energy of arc in a gas circuit breaker(GCB). The PM-Tube, LLG(liquid light guides), ND(neutral density) filter, and a model gas circuit breaker have been combined for the reception and the transmission of the light and a simplified synthetic test facility with the arc energy measuring system has been established. In the case of $SF_6$ gas pressure $5kg.f/cm^2$ and arc length 20mm, the radiation energy increases with the arc current but it tend to be saturated in the above 20kA. Under the arc current 20kA, the total radiation energy has the biggest value around 8kA and was not exceeded 40% of the total arc energy.

광속법을 이용한 기체의 전이계수 측정 (Measurement of the Ionization Coefficient in Gases by the Luminous-flux Method)

  • 백용현;하성철;이복희;김희택;김정섭
    • 대한전기학회논문지
    • /
    • 제34권7호
    • /
    • pp.289-296
    • /
    • 1985
  • The Townsend primary ionization coefficient a was measured by the luminous-flux method using the fact that the intensity of radiant light is proportional to electron density in the townsend discharge domain. The ranges of measurements were 15for He gas and 10

  • PDF

GM Tube 및 NaI(TI) 검출기를 사용한 Wide-Range 방사선 측정 시스템의 설계 (Design of Wide-Range radiation measurement system using GM Tube and NaI(TI) Detector)

  • 라승탁;이주현;이승호
    • 전기전자학회논문지
    • /
    • 제21권2호
    • /
    • pp.146-149
    • /
    • 2017
  • 본 논문에서는 GM Tube 및 NaI(TI) 검출기를 사용한 Wide-Range 방사선 측정 시스템을 제안한다. 제안하는 시스템은 NaI(Tl) 검출기 및 GM Tube의 검출기 신호를 제어, 계수할 수 있게 최적화한 하나의 소형 모듈로 설계한 다. 방사선량은 2개의 검출기를 연동하여 Wide-range인 0.1uSv/h~10mSv/h 구간에서 측정되고, 측정구간이 중복되는 지점인 10uSv/h~100uSv/h에서는 2개의 검출기가 동시에 동작한다. 방사선량은 중첩된 방사선 측정 가능 구간에 대해 적정한 구간에서 해당 검출기 기능의 On/Off를 제어하는 Wide-Range 방사선 측정 알고리즘을 이용하여 선택 적용하였다. 제안된 시스템의 성능을 평가하기 위하여 공인시험기관에서 실험한 결과, 각 구간별로 측정 불확도가 ${\pm}7.5%$로 측정되어 국제 표준인 ${\pm}15%$ 이하에서 정상동작 됨이 확인되었다.

CsI:Gd 결정 육성과 섬광 특성 (Crystal Growth and Scintillation Properties of CsI:Gd)

  • 천종규;김성환;김홍주
    • 센서학회지
    • /
    • 제21권4호
    • /
    • pp.293-297
    • /
    • 2012
  • CsI:Gd crystal was grown by the Bridgeman method and its scintillation properties were investigated. The wavelength peak of the luminescence spectrum for the crystal excited by X-ray was 419 nm. The range of the spectrum was from 300 nm to 800 nm. The spectrum well matched to the quantum efficiency of a typical bi-alkali photo-multiplier tube(PMT). An energy resolution of 48.2 % was obtained for 662 keV ${\gamma}$-rays of $^{137}Cs$. The three decay times were obtained as a fast(557.4 ns, 42.2 %), intermediate (1.78 ${\mu}s$, 29.7 %) and slow (5.43 ${\mu}s$, 28.1 %) components, respectively.

불평등전극계에서 뇌임펄스전압에 대한 $N_2$기체의 절연파괴 특성 (The breakdown characteristics of $N_2$ gas with lightning impulse voltage in the non-uniform electrode)

  • 이복희;이봉;조정현
    • 한국조명전기설비학회:학술대회논문집
    • /
    • 한국조명전기설비학회 2008년도 춘계학술대회 논문집
    • /
    • pp.301-304
    • /
    • 2008
  • This paper presents the experimental results on breakdown characteristics in $N_2$ gas under non-uniform electric fields caused by both the positive and negative lightning impulse voltages. $N_2$ gas have an advantage of eco-friendly and cost reduction, and safety aspects. In order to analyze the impulse pre-breakdown processes in $N_2$ gas, we carried out measurements and observations of the impulse breakdown voltages, pre-breakdown current and luminous signals. They were measured by a voltage divider, a shunt and a photo-multiplier tube, respectively. Additionally, the characteristics of discharge channels were observed by high speed cameras. The breakdown voltages in the positive polarity was lower than those in the negative polarity.

  • PDF

불평등전장에서 $SF_6$$SF_6/N_2$ 혼합기체의 뇌임펄스 전압에 대한 코로나 방전특성 (Characteristics of lightning impulse corona discharges under non-uniform electric fields in $SF_6$ and $SF_6/N_2$ mixtures)

  • 이복희;오성균
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.129-132
    • /
    • 2004
  • This paper presents an experimental study on the prebreakdown characteristics in $SF_6/N_2$ mixtures under non-uniform electric fields when subjected to the positive and negative lightning impulse voltages. $SF_6/N_2$ mixtures have a merit of an environmental aspect and cost reduction, and safty aspects. In order to analyze the prebreakdown processes in $SF_6/N_2$ mixtures stressed by impulse voltages, prebreakdown current and light were observed by a shunt with high sensitivity and a photo-multiplier tube, respectively. Additionally, characteristics of luminous events in flashovers were discussed.

  • PDF

소노루미네센스를 이용한 액체정합층의 고출력 초음파에너지 전달특성 평가 (Evaluation of high power ultrasonic energy transmission characteristics of a liquid matching layer by using sonoluminescence)

  • 김정순;김해운;손진영;김무준
    • 한국음향학회지
    • /
    • 제40권5호
    • /
    • pp.408-416
    • /
    • 2021
  • 초음파 분산에 있어서 초음파의 방사면이 시료에 직접 닿는 것을 피하기 위해 액체시료는 유리용기에 의해 분리되어 음향매질에 의해 초음파 에너지를 받는다. 이와 같이 다층구조로 이루어진 음향시스템에서 초음파에너지의 전달효율은 중요한 요소이다. 본 연구에서는 다층구조로 이루어진 음향시스템에 있어서 프로필렌글리콜 용액을 액체정합층으로 사용하여 초음파에너지 전달효율을 개선하는 방법을 제안하였다. 제안된 방법에서는 란주반형 초음파 트랜스듀서와 루미놀용액과의 사이에 프로필렌글리콜 용액을 액체정합층 매질로 채우고, 초음파트랜스듀서로부터 방사되는 강력초음파의 비선형현상에 의해 발광되는 루미놀용액의 발광정도를 광전증폭관을 이용하여 관측하여 루미놀용액으로의 초음파에너지 전달 효율을 조사하였다. 프로필렌글리콜 농도변화에 따른 초음파에너지 전달정도를 측정하였고, 그 결과 프로필렌글리콜 용액의 농도가 증가함에 따라 정합효과는 증가하는 반면 음향감쇠가 증가함을 알 수 있었다. 이들 두 상충되는 조건이 절충되는 최적의 농도가 존재함을 확인할 수 있었으며, 프로필렌글리콜 용액의 최적 농도를 실험적으로 결정할 수 있었다.

배연가스의 $NO_x$제거용 코로나 방전장치에서 OH 발광 스펙트럼 측정 및 관련 반응 연구 (Study on the Measurement of Emission Spectrum and Reaction Mechanism of OH Radical in the Nitrogen Corona Discharge System for Removal of $NO_x$ in Flue Gas)

  • 박철웅;한재원;신동남
    • 한국연소학회지
    • /
    • 제4권1호
    • /
    • pp.27-38
    • /
    • 1999
  • We constructed a wire-cylinder type pulsed corona discharge system for $NO_x$ removal, which was operated in room temperature. A emission spectrometer was built with a boxcar averager and monochrometer equipped with photo-multiplier tube detector. The sensitivity of the emission spectrometer was greatly improved by synchronizing the emission spectrometer with pulsed corona discharge system using a triggered spark-gap switch. $N_2$ spectrum($c^3{\Pi}_u{\rightarrow}X^1{\Sigma}_g{^+}$) was measured in the range of 300 - 450 nm and oxidizing OH radical emission($A^2{\Sigma}^+{\rightarrow}X^2{\Pi}$) was measured in case $N_2$ was supplied with water bubbling. As wet gas composition of inlet $N_2$ supplied in the discharge system increased, the intensity of OH emission was increased and saturated at wet gas composition 50%. We also investigated additive effect of $C_2H_4,\;H_2O,\;H_2O_2$ on the intensity of OR emission and $NO/NO_2/NO_x$ reduction and analysed the related reaction mechanism in corona discharge process. $H_2O_2$ additive increased the intensity of OH emission and $NO/NO_x$ reduction.

  • PDF