• 제목/요약/키워드: Radiation Measurement

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Photo diode에 의한 일사량 측정(관개배수 \circled2) (Measurement of radiation using photo diodes)

  • 이남호;김기복;백성호
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2000년도 학술발표회 발표논문집
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    • pp.200-205
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    • 2000
  • The purpose of this study is to develop an economical radiation sensor using photo diodes. An electronic circuit was developed. The behavior of the radiation sensor was evaluated by increasing number of photo diodes. The sensor became more reliable by the increase in number of photo diodes. It was showed that the photo diodes sensor would be applicable.

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한국의 세 개의 다른 식생기능형태에서의 순복사 추정 논문에 대한 의견 (Comment on "Estimation of Net Radiation in Three Different Plant Functional Types in Korea")

  • 강민석;김준
    • 한국농림기상학회지
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    • 제11권3호
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    • pp.118-122
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    • 2009
  • Net Radiation ($R_N$) is the major driving force for biophysical and biogeochemical processes in the terrestrial ecosystems, which is one of the most critical variables in both measurement and modeling. Despite its importance, there are only 10 weather stations conducting $R_N$ measurements among the 544 stations operated by Korea Meteorological Administration (KMA; KMA, 2008). The measurement of incoming shortwave radiation ($R_S{\downarrow}$) is, however, conducted at 22 stations while that of sunshine duration is conducted at all the manned stations. In this context, the recent research for estimating $R_N$ using $R_S{\downarrow}$ in Korean peninsula by Kwon (2009) is of great worth. The author used a linear regression and the radiation balance methods. We generally agree with the author that, in terms of simplicity and practicality, both methods show reliable applicability for estimating $R_N$. We noted, however, that the author's experimental method and analysis need some clarification and improvement, that are addressed in the following perspectives: (1) the use of daily integrated data for regression, (2) the use of measured albedo, (3) the use of linear coefficients for whole year data, (4) methodological improvement, (5) the use of sunshine duration, and (6) the error assessment.

인듐안티모나이드(InSb) 소자를 이용한 적외선 방사온도 계측시스템의 개발연구 (Development of Radiation Thermometer using InSb Photo-detector)

  • 황병옥;이원식;장경영
    • 한국정밀공학회지
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    • 제12권7호
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    • pp.46-52
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    • 1995
  • This paper proposes methodologies for the development of radiation thermometer using InSb photo-detector of which spectral sensitivity is excellent over the wave length range of 2 .mu. m .approx. 5 .mu. m. The proposed radiation thermometer has broad measurement range from normal to high, up to more than 1000 .deg. C, with high accuracy, and can measure temperature on the material surface or heat emission noncontactely with high speed. Optical system was consisted of two convex lens with foruslength of 15.2mm for infrared lay focusing, Ge filter to cut the short wave length components and sapphire filter to cut the long wave length components. The cold shielded was installed in the whole surface of the light-absorbing element to remove the error- mometer, calibration using black body furnace which has temperature range of 90 .deg. C .approx. 1100 .deg. C was carried out, and temperature calaibration curve was obtained by exponential function curvefitting. The result shows maximum error less than 0.24%(640K .+-. 1.6K) over the measurement range of 90 .deg. C .approx. 700 .deg. C, and from this result the usefulness of the developed thermometer has been confirmed.

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이동형 X선 장치 차폐도구 제작을 통한 표면선량 분포 측정 (Measurement of Skin Dose Distribution for the Mobile X-ray Unit Collimator Shielding Device)

  • 홍선숙;김득용
    • 대한디지털의료영상학회논문지
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    • 제12권1호
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    • pp.5-8
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    • 2010
  • Opened a court in February 10, 2006, a rule of safety management of the diagnosis radiation system was promulgated for safety of the radiation worker, patients and patients' family members. The purpose of this rule is to minimize the risk of being exposed to radiation during the process of handling X-ray. For this reason, we manufactured shielding device of mobile X-ray unit collimator for diminution of skin dose. Shielding device is made to a thickness of Pb 0.375mm. For portable chest radiography, we measured skin dose 50cm from center ray to 200cm at intervals of 20cm by Unfors Xi detector. As a result, a rule of safety management of the diagnosis radiation system has been strengthened. But there are exceptions, such as ER, OR, ICU to this rule. So shielding device could contribute to protect unnecessary radiation exposure and improve nation's health.

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Measurement of Bremsstrahlung Radiation with Electron Beam Energy

  • Srivastava, R.P.;Chaurasia, P.P.;Prasiko, G.;Jha, A.K.
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.235-236
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    • 2002
  • A Klystron powered dual photon energy electron linear accelerator 2300 C/D from Varian Associates has been installed in our center. From the radiological safety view as well as treatment planning, the output (contamination) of Bremsstrahlung Radiation with electron beam energy determined accurately. It has been found 0.5% to 4.7% with increasing the electron beam energy which is the clinically not much significant in the treatment of the malignant diseases with the treatment of electron beam.

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접수 원통형 구조물의 표면 진동속도를 이용한 총 방사음향파워 계산 (Estimation of Total Acoustic Radiation Power of Submerged Circular Cylindrical Structure Using Surface Vibration Velocity)

  • 한승진;이종주;강명환;배수룡;정우진
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.236-239
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    • 2014
  • Most naval underwater weapon system can be simplified to a circular cylindrical structure which has vibrating machineries inside. In order to predict efficiently the total acoustic radiation power of cylindrical structure, surface velocity is measured and radiation efficiency of surface element is calculated. Then, they are substituted to the surface pressure in the simplified Helmholtz integral equation which assumes acoustic far-field and plane-wave approximation at the surface. Surface velocity and total acoustic radiation power for a submerged cylinder are measured in water-tank. In this example, it is found that total acoustic power output obtained from the prediction is in good agreement with that of measurement in mid-high frequency range.

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자외성 페라이트 진동자의 지향특성에 대하여 (Radiation Pattern of the Vibrox Transducer)

  • 신형일
    • 한국항해학회지
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    • 제4권2호
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    • pp.1-6
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    • 1980
  • Computer simulation results on the radiation pattern of an ultrasonic beam by the plurall arrangement of the transducers were reported by Sin (1979). This paper describes on the measurement of radiation pattern in case of one vibrox transducer and two vibrox transducers by varying the interval between the transducers. The measured results obtained are as follows; 1. Radiation wave of ultrasonic transducer is propagated to diffuse with spherical wave from center of transducer. 2. In case of one vibrox transducer, the greater the length of transducer, the sharper becomes the radiation pattern. 3. In case of two vibrox transducers, the maine lobe is revealed at the center of two transducers, it is shown difficult to make control freely of radiation pattern by varying merely the interval of transducers.

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Efficacy Evaluation of Alpha/Beta Radioactivity Screening in Urine Samples using Liquid Scintillation Counting

  • Ki Hoon Kim;Jae Seok Kim;Won Il Jang;Seokwon Yoon
    • 방사선산업학회지
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    • 제18권2호
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    • pp.101-107
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    • 2024
  • Rapid screening for internal contamination by alpha- and beta-emitting radionuclides is essential in situations involving radiation workers or radiation accidents. This study focused on the use of urine samples and liquid scintillation counting to quickly and accurately assess contamination. Calibration of the alpha and beta detection areas ensured precise measurement results. The major radionuclides recommended for surveillance during accidents were also considered. This study evaluated the effectiveness of the method by examining various parameters, including the limit of detection, linearity, sensitivity, selectivity, accuracy, ruggedness, and blind test sample analysis. The liquid scintillation counting method is an effective tool for screening urinary samples to detect alpha- and beta-emitting radionuclides, particularly during radiation emergencies, despite some limitations in precision.

CMOS 이미지 센서를 사용한 방사선 측정에 관한 연구 (A Study On Radiation Detection Using CMOS Image Sensor)

  • 이주현;이승호
    • 전기전자학회논문지
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    • 제19권2호
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    • pp.193-200
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    • 2015
  • 본 논문에서는 CMOS 이미지 센서를 사용한 방사선 측정 알고리즘 및 장치의 구성을 제안한다. CMOS 이미지 센서를 사용한 방사선 측정 알고리즘은 CMOS 이미지 센서에 입사된 방사선 입자 판별 알고리즘과 CMOS 이미지 센서로 매초 수 십장의 이미지에 입사된 방사선 입자에 대한 픽셀 수의 누적 및 평균을 기준으로 하는 방사선 수치 측정 알고리즘을 사용한다. CMOS 이미지 센서에 입사된 방사선 입자 판별 알고리즘은 입사된 방사선 입자의 이미지를 R, G, B로 분할하고 각각의 이미지에 대해 명암 및 백그라운드와 입자를 구별할 수 있는 임계값 설정 조정을 통하여 측정한다. 방사선 수치 측정 알고리즘은 설정된 주기에 따른 CMOS 이미지 센서로 매초 수 십장의 이미지에 입사된 방사선 입자수를 누적 저장, 평균을 통하여 방사선 수치를 측정한다. 제안된 알고리즘의 검증을 위한 하드웨어 장치는 CMOS 이미지 센서 및 이미지 시그널 프로세서부, 제어부, 전원회로부, 디스플레이부 등으로 구성된다. 제안된 CMOS 이미지 센서를 사용한 방사선 측정에 관하여 실험한 결과는 다음과 같다. 첫 번째로 저가의 CMOS 이미지 센서를 사용하여 방사선 입자 판별 측정 실험을 통해 고가의 GM Tube의 측정 구간별 특성과 대체로 유사한 특성을 나타낼 수 있음을 확인할 수 있었다. 두 번째로 저가의 CMOS 이미지 센서로 방사선 수치 측정 실험을 통해 고가의 GM Tube가 나타내는 선형 특성과 대체로 유사한 특성을 나타냄을 확인할 수 있었다.