The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In view of the inherent speckle noise in medical ultrasound images, a novel method is proposed based on the blind deconvolution and the Maximum-Likelihood (ML) filtering. Firstly, the point spread function (PSF) is blindly estimated based on the complex-cepstrum filtering; then the PSF is input into a Wiener Filter in order to recover the tissue reflectivity. Secondly, the reflectivity is reasonably...
This work presents an approach to extend the dynamic range of X-ray flat-panel detectors for cone-beam micro-CT by using two different acquisitions of the same sample, taken at two different X-ray photon fluxes with the same X-ray beam peak energy and filtration. Photon flux for the first scan is chosen as the maximum possible value not saturating the detector in the low attenuation areas. The second...
In this work we compare images obtained from different list-mode reconstruction algorithms for PET data. Our analysis is based on list-mode data generated from a Geant4 simulation of the Jaszczak phantom. The first issue addressed is the influence of the raytracer used during reconstruction on the quality of the resulting images. We find that the Wu anti-aliased raytracer leads to better images than...
An accurate system model is essential for reconstructing high-resolution images. While the system response of a positron emission tomography (PET) system can be measured directly, the process is often difficult to perform and time-consuming. Here we propose a maximum likelihood method for estimating the detector response from projections of a point source at a set of radial locations in the field...
An accurate system model is essential for reconstructing high-resolution images. While the system response of a positron emission tomography (PET) system can be measured directly, the process is often difficult to perform and time-consuming. Here we propose a maximum likelihood method for estimating the detector response from projections of a point source at a set of radial locations in the field...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.