• 제목/요약/키워드: sensitive measurement

검색결과 840건 처리시간 0.072초

PSP를 이용한 노즐벽면의 압력해석 (Pressure Analysis on the nozzle wall with PSP)

  • 김기수;배영우;이재우;변영환
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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    • pp.409-412
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    • 2005
  • 본 논문에서는 Pressure Sensitive Paint(이하 PSP)를 이용한 M=2.5 초음속 풍동의 노즐 벽면 압력 측정 과정을 보여주고, NASA Lewis Research Center에서 유사한 조건에서 수행한 실험결과와 비교하였다.

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Design of a Sensitive ac Magnetic Susceptibility

  • D. K. Oh;Lee, Cheol-Eui;J.I. Jin;S. J. Noh
    • Journal of Magnetics
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    • 제2권2호
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    • pp.55-57
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    • 1997
  • A mutual-inductance bridge type ac magnetic susceptibility measurement system was built in our laboratory. With addition of a phase-sensitive prestage, it was simple to implement and provided a high signal-to-noise (S/N) ratio.

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변위측정을 위한 선형 CCD 센서와 PSD 센서의 성능 비교에 관한 연구 (Study on Comparing the Performance of Linear CCD sensor with PSD sensor for Distance Measurement)

  • 신명관;박기환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 D
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    • pp.2167-2169
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    • 2004
  • The main concern for a displacement measurement is the performance of a sensor such as speed, resolution, accuracy and so on. The mainly used sensors are a linear CCD(charge coupled device) and a PSD(position sensitive detection) as a non-contact type. The output value of a linear CCD is so sensitive to a temperature change that it needs a cooling device. Additionally, because of its structural problem, there are some limits in resolution and speed, and it needs a complex image processing algorithm. Also, PSD has some disadvantages like sensitivity to environmental lights and nonlinearities. Like this, a linear CCD and PSD have their own characteristics and if we know them well, we can choose the one of the two sensors properly in some applications according to purposes. In this paper, I performed which one is superior to the other among the two sensors in terms of accuracy, resolution, measurement speed, signal to noise ratio.

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RADIATION SAFETY STUDIES AT TOHOKU UNIVERSITY CYRIC

  • Yamadera M. Baba A.;Miura T.;Aoki T.;Hagiwara M.;Kawata N.
    • Journal of Radiation Protection and Research
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    • 제26권3호
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    • pp.231-236
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    • 2001
  • A brief introduction is presented on the radiation safety studies at Tohoku University Cyclotron & Radioisotope Center. Studies on two subject are described; (1) measurement of the thick target neutron yield and radioisotope production / activation cross section for ten's of MeV neutrons and ions using K=110 Tohoku University cyclotron to provide basicdata for accelerator shielding, and (2) development of techniques for high sensitive radiation detection and profile measurement using an Imaging Plate which is a high sensitive two-dimensional radiation sensor. Application of the Imaging Plate techniques to localization of very weak radioactivity and to neutron profile measurement is described.

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Does National Distance Affect Different Industries in Different Ways? A Test of the Ghemawat CAGE Model

  • Kim, Hak Cho;Kwon, Jong-Wook;Zhou, Zhibin;Heo, Ji Hyun
    • Journal of Korea Trade
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    • 제23권7호
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    • pp.13-33
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    • 2019
  • Purpose - This study empirically investigated whether national distances (Cultural, Administrative, Geographic and Economic distance) have different effects on industries in different ways. Design/methodology - The empirical model utilized industry level export trade data to examine the differentiated effects of each national distance. By using direct measurement and covering 75 countries, this paper analyzes the effect of distances in different industries. More specifically, this study classified the industries into a more-sensitive/less-sensitive scale. Findings - The empirical results showed the complicated impacts of national distances on trade. Trade in industries that are more sensitive to cultural and administrative distances was not decreased as greatly as trade in industries that are less sensitive to cultural and administrative distances. Also, industries that are more sensitive to geographic distance showed a stronger negative impact on trade than less sensitive industries. Lastly, economic distance decreased trade for industries that are more sensitive to economic distance, while economic distance did not significantly increase trade for industries that are less sensitive to economic distance. Originality/value - As the first study to empirically find out whether national distance has different effects on industries, this study updated the measurements of national distance.

청년층과 노인층의 행동활성화체계 및 행동억제체계 민감도에 따른 뇌파의 1/f 스케일링 분석 (1/f scaling exponent of EEG depending on different sensitivities of behavioral activation and inhibition systems for young and elderly groups)

  • 진승현;김원식;노기용
    • 감성과학
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    • 제8권4호
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    • pp.415-422
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    • 2005
  • 본 연구에서는 행동활성화체계(Behavioral Activation System : BAS)와 행동억제 체계(Behavioral Inhibition System : BIS)의 성향이 청년층과 노인층의 뇌파 특성에 차이를 보이는지를 조사하였다. 실험은 19명의 청년층과 31명의 노인층을 대상으로 하여 이루어졌고, 안정 상태의 양측 전전두엽 뇌파를 측정하였다. 분석은 비선형 지수 중 하나인 1/f스케일링 지수를 사용하였다. 그 결과, BAS 성향에서 1/f스케일 지수가 유의한 차이를 보였다. 즉, 좌측 전전두엽(Fpl)에서는 청년층의 1/f스케일 지수가 노인층의 1/f스케일 지수보다 통계적으로 유의하게 높은 값을 보였고, 우측 전전두엽(Fp2)에서도 청년층이 노인층에 비해 높은 1/f스케일 지수를 나타내는 경향을 보였다. 1/f 스케일 지수가 클수록 복잡도는 감소하고, 반면 확률분포에 관련된 정보의 양은 증가하는 것으로 해석 가능하다. 본 연구를 통해, 주관적 평가 결과로서 행동 활성화체계가 강한 성향을 가진 경우, 노인층은 청년층에 비해 양측 전전두엽의 복잡도가 높은 상태임을 알 수 있다 본 연구의 결과는 BAS성향과 연령 사이의 연관성에 대한 가능성을 시사한다.

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임상가를 위한 특집 3 - 교합력 측정의 방법과 임상적 적용 (The methods for occlusal force measurement and their clinical applicatio)

  • 박지만;허성주;전윤식
    • 대한치과의사협회지
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    • 제50권1호
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    • pp.22-30
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    • 2012
  • The methods for the occlusal force measurement have long been developed. The occlusal analyzing equipment utilizing the pressure-sensitive film (Prescale) is useful for the assessment and comparison among large group of patients. On the other hand, the apparatus which uses the grid-based sensor sheet (T-scan) can be a useful assistant for acquiring the well-balanced occlusion. The device that can process the electrical input from the strain gauge which is attached to the tooth surface can collect the dynamic data of actual masticatory force. This device has been developed for the measurement of actual mastication with the food bolus and it can be a useful method for the comparison before and after the restorative treatment. Occlusal force measurement can be applied for the analysis of therapeutic action, diagnosis of crack- tooth syndrome, temporomandibul ar disease, and idiopathic implant loosening.

ITO막의 두께 제어를 위한 투과율 측정 (Transmittance measurement for thickness control of ITO layer)

  • 박정규;이무영
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.213-213
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    • 2000
  • A sensor system which can measure the transmittance of ITO(Indium Tin Oxide) layed glass is proposed. The sensor system includes a single wavelength laser beam source, photo diodes and electronic circuit processing sensor signal. The wavelength of laser is 543.5 m, this is most sensitive wavelength to photopic and scotopic vision. We applied the sensor to measure transmittance of ITO layer on general manufacturing environment and verified the effectiveness of sensor through experimental measurement.

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Measurements of low dose rates of gamma-rays using position-sensitive plastic scintillation optical fiber detector

  • Song, Siwon;Kim, Jinhong;Park, Jae Hyung;Kim, Seunghyeon;Lim, Taeseob;Kim, Jin Ho;Kim, Sin;Lee, Bongsoo
    • Nuclear Engineering and Technology
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    • 제54권9호
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    • pp.3398-3402
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    • 2022
  • We fabricated a 15 m long position-sensitive plastic scintillation optical fiber (PSOF) detector consisting of a PSOF, two photomultiplier tubes, four fast amplifiers, and a digitizer. A single PSOF was used as a sensing part to estimate the gamma-ray source position, and 137Cs, an uncollimated solid-disk-type radioactive isotope, was used as a gamma-ray emitter. To improve the sensitivity, accuracy, and measurement time of a PSOF detector compared to those of previous studies, the performance of the amplifier was optimized, and the digital signal processing (DSP) was newly designed in this study. Moreover, we could measure very low dose rates of gamma-rays with high sensitivity and accuracy in a very short time using our proposed PSOF detector. The results of this study indicate that it is possible to accurately and quickly locate the position of a very low dose rate gamma-ray source in a wide range of contaminated areas using the proposed position-sensitive PSOF detector.