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Yoshio Machida
Researcher at Tohoku University
Publications - 22
Citations - 270
Yoshio Machida is an academic researcher from Tohoku University. The author has contributed to research in topics: Imaging phantom & Image noise. The author has an hindex of 8, co-authored 22 publications receiving 222 citations.
Papers
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Journal ArticleDOI
Photon starvation artifacts of X-ray CT: their true cause and a solution
TL;DR: A new scheme of local raw data filtering is proposed, which consists of reverting log-converted raw data to a form that is equivalent to pre-log detector data and, with this method, not only fine streaks, but also thick streaks are removed effectively.
Journal ArticleDOI
Deriving the modulation transfer function of CT from extremely noisy edge profiles.
Issei Mori,Yoshio Machida +1 more
TL;DR: A technique for rendering the ESF method robust to image noise is described, and the MTF obtained by the method is sufficiently consistent with the theoretical MTF, even when the CNR is as low as 2.5%.
Journal ArticleDOI
Synthesis of Gd2O3 nanoparticles for MRI contrast agents
N. Sakai,L. Zhu,A. Kurokawa,H. Takeuchi,S. Yano,T. Yanoh,N. Wada,Shu Taira,Yoshiyuki Hosokai,Akihito Usui,Yoshio Machida,Haruo Saito,Yuko Ichiyanagi +12 more
TL;DR: In this article, Gd2O3 nanoparticles were synthesized by using the original method for application as MRI contrast agents, and the sample diameters were controlled in the range 18-66 nm by adjusting the annealing temperature between 773 and 1273 K in air or in an Ar atmosphere.
Journal ArticleDOI
Method of SNR determination using clinical images
Akio Ogura,Tosiaki Miyati,Masato Kobayashi,Hiroshi Imai,Kouzou Shimizu,Toshio Tsuchihashi,Tsukasa Doi,Yoshio Machida +7 more
TL;DR: In this paper, the authors investigated the possibility of a subtraction method using clinical images and the accuracy of standard deviation (SD) of clinical images for optimum ROI, which was not possible to use the air-signal method.
Journal ArticleDOI
[Signal-to-noise ratio measurement in parallel MRI with subtraction mapping and consecutive methods].
Hiroshi Imai,Tosiaki Miyati,Akio Ogura,Tsukasa Doi,Toshio Tsuchihashi,Yoshio Machida,Masato Kobayashi,Kouzou Shimizu,Yoshihiro Kitou +8 more
TL;DR: Two methods are proposed to obtain a more detailed determination of SNR in parallel imaging and to calculate the geometry factor, which agrees with those of the consecutive method.