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Utsunomiya-shi, Japan

Raytech Inc. | Date: 2015-06-30

Microwave transmission apparatus for delivering radio programs and messages.

Kanno I.,Kyoto University | Minami Y.,Kyoto University | Minami Y.,Toshiba Corporation | Imamura R.,Kyoto University | And 7 more authors.
Journal of Nuclear Science and Technology | Year: 2011

To enable practical computed tomography (CT) that uses the energy information of X-rays, the ''transXend detector'' was developed to provide energy information about incident X-rays by measuring them as an electric current. The transXend detector requires a spectrum survey method in the unfolding process for measuring the energy distribution of incident X-rays, when the response functions of segment detectors have nearly the same behavior. When employing various scintillators with different effective atomic numbers and densities as the substrates of the segment detectors, better convergence is obtained in the unfolding process by using only one initial guess spectrum. Additionally, less dose exposure is possible when using the transXend detector with various segment detectors, compared with the transXend detector that consists of the segment detectors with the same substrate. © 2011 Atomic Energy Society of Japan.

Imamura R.,Kyoto University | Mikami K.,Kyoto University | Minami Y.,Kyoto University | Minami Y.,Fuji Electric Co. | And 5 more authors.
Journal of Nuclear Science and Technology | Year: 2010

The computed tomography (CT) values obtained by the energy subtraction method with a transXend detector, which measured X-rays as current and gave the corresponding X-ray energy information, show the disadvantage that the CT values are dependent on the thickness of a homogeneous phantom. In order to obtain constant CT values for a uniform material, a new unfolding method is proposed using variable response functions of the transXend detector according to the X-ray path length in the phantom. The CT values measured using the new unfolding method are discussed with respect to the energy range used in the unfolding process, the number of segment detectors, and the substrate of the segment detectors. © Atomic Energy Society of Japan.

Minami Y.,Kyoto University | Imamura R.,Kyoto University | Kanno I.,Kyoto University | Ohtaka M.,Japan Atomic Energy Agency | And 3 more authors.
Journal of Nuclear Science and Technology | Year: 2011

X-ray computed tomography (CT) using X-ray energy information has been studied by the present authors on acrylic phantoms containing an iodine contrast medium. To observe a human body, however, it is necessary to consider the bone. In this paper, CT measurements were made on a phantom with regions of both iodine and aluminum, which was used as a substitute for the bone. A filtered back-projection method and a maximum likelihood-expectation maximization method were employed for image reconstruction. © Atomic Energy Society of Japan.

Kanno I.,Kyoto University | Imamura R.,Kyoto University | Minami Y.,Kyoto University | Ohtaka M.,Japan Atomic Energy Agency | And 3 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2012

The present authors developed the transXend detector, which measures incident X-rays as current and also gives their energy distribution after an unfolding process with using previously obtained response functions. This detector enables X-ray energy-resolved computed tomography (CT). To incorporate the transXend detector into a third-generation CT scanner, a flat panel detector (FPD) made of CdTe pixels is employed with placing a variable number of aluminum absorbers in front of the FPD. Although changing the number of absorbers can be time consuming, the time necessary to generate a CT image is much less when compared with image acquisition by first-generation CT. © 2011 Elsevier B.V.

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