| Project/Area Number |
60580182
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Nuclear engineering
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| Research Institution | Kyoto Institute of Technology |
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Principal Investigator |
KANAMORI Hitoshi Kyoto Institute of Technology , Professor, 工芸学部, 教授 (70027770)
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| Co-Investigator(Kenkyū-buntansha) |
MATSUMOTO Masao Osaka Prefectural Technical College , Associate Professor, 助教授 (50149944)
NAKAMORI Nobuyuki Kyoto Institute of Technology , Research Associate, 工芸学部, 助手 (20107353)
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| Project Period (FY) |
1985 – 1986
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| Project Status |
Completed (Fiscal Year 1986)
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| Budget Amount *help |
¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1986: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1985: ¥700,000 (Direct Cost: ¥700,000)
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| Keywords | Medical x-ray imaging / Patient exposure / 画質 / X線スペクトル |
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| Research Abstract |
In diagnostic radiography, a large x-ray tube current value of hundreds mA is required. Therefore, in measuring x-ray spectra with the factors used in diagnostic radiography, a germanium detector receives too large photon fluence rate which causes great error due to the pile up phenomenon. We have developed low capacity cables, and reduced the photon fluence rate by decreasing the tube current to less than a few mA without changing the high voltage waveforms. Then the measurement of the x-ray spectra with diagnostic radiographic factors was readily performed.
Photon spectra were measured for various tube-voltage ripple rates, and various object thickness of aluminum and acrylic resin at 70 kV. The photon spectra were converted to energy spectra and exposure spectra, and then attenuation curves were obtained.
Dependence of relative exposures at surface position of objects and mAs values on high-voltage ripple-rate was estimated using X-ray spectra, spectral speeds of the six screen-film systems, exposure attenuation curves, and speed attenuation curves. It has been verified quantitatively that 3-phase X-ray units are better than single-phase X-ray units from the view points of patient exposure and image quality in diagnostic radiology.
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