| Project/Area Number |
11650419
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Measurement engineering
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| Research Institution | Tokyo University of Agriculture and Technology |
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Principal Investigator |
YAMADA Akira Tokyo University of Agriculture and Technology, Graduate School of Bio-Applications & Systems, Associate Professor, 大学院・生物システム応用科学研究科, 助教授 (20159213)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2000: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1999: ¥2,800,000 (Direct Cost: ¥2,800,000)
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| Keywords | Ultrasonic CT / Acoustic inverse scattering / Modified linearization approximation / Image reconstruction / Diffraction tomography / Sound speed and attenuation image / Circular arc observation / Backward prop. Rytov approximation / 音速画像 / 3次元画像 |
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| Research Abstract |
A technique was developed for reconstructing sound speed and attenuation quantitative computerized tomographic images of biological tissues based on the modified linearization inverse scattering analysis. So far, there was a problem that large sound speed contrast (less than 10 %) of the biological tissues violates the weak scattering linearization approximation conditions and causes crosstalk errors in the reconstructed attenuation image. In addition, attenuation scattering wave components were very small compared to that of sound speed, hence the measurement noise contamination was inevitable in the attenuation image. In this paper, following methodologies were introduced to resolve the problems. (1)Modified linearization method based on the backward propagation Rytov approximation was examined based on the combination of the inverse and forward scattering, analysis to compensate the errors in the attenuation image. (2)The circular arc data observation was made in place of the conventional straight line observation. It was demonstrated that optimal selection of the circular observation distance and angular observation aperture made it possible to avoid the spurious edge wave interference and improve the robustness against the measurement noise. Through simulation and/experiment test examinations, it was verified that attenuation image with good quantitative precision was successfully reconstructed.
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