introduction echo-planar imaging (epi) is a group of fast data acquisition methods commonly used in fmri studies. it acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. a well-known problem with epi is that it is more sensitive to distortions due to the used encoding scheme. source of distortion is inhomogeneity in the static b0 field that ...

abtract background: in nuclear medicine, phantoms are mainly used to evaluate the overall performance of the imaging systems and practically there is no phantom exclusively designed for the evaluation of the software performance.  in this study the hoffman brain phantom was used for quantitative evaluation of reconstruction techniques. the phantom is modified to acquire tomographic and planar i...

density functional theory (dft) calculations were performed to investigate the properties of planar, tubular and conical forms of silicon nanostructures. the evaluated parameters including averaged bond lengths, binding energies, gap energies and dipole moments were then evaluated for the optimized models of study. the results indicated that the bond lengths between silicon atoms are different ...

Density functional theory (DFT) calculations were performed to investigate the properties of planar, tubular and conical forms of silicon nanostructures. The evaluated parameters including averaged bond lengths, binding energies, gap energies and dipole moments were then evaluated for the optimized models of study. The results indicated that the bond lengths between silicon atoms are different ...

Density functional theory (DFT) calculations were performed to investigate the properties of planar, tubular and conical forms of silicon nanostructures. The evaluated parameters including averaged bond lengths, binding energies, gap energies and dipole moments were then evaluated for the optimized models of study. The results indicated that the bond lengths between silicon atoms are different ...

G-frames are natural generalizations of frames which provide more choices on analyzing functions from frame expansion coefficients. First, they were defined in Hilbert spaces and then generalized on C*-Hilbert modules. In this paper, we first generalize the concept of g-frames to Hilbert modules over pro-C*-algebras. Then, we introduce the g-frame operators in such spaces and show that they sha...