Efektywny algorytm obrazowania w tomografii ultradźwiękowej i radiowej dla zagadnień dwuwymiarowych

A New Concept of Discretization Model for Imaging Improving in Ultrasound Transmission Tomography

“…the standard circular pixel and the increased circular pixel, the distribution practically did not differ much. In previous works [11,13] for noise free signal correctness of the novel discretisation was proved. To demonstrate the advantages of pixel enlargement, a synthetic signal with 5% noise was considered, as shown in Fig.…”

“…4. The 32 sensors fixed on the perimeter of the region were considered as it was done in our previous works see for example [13]. The Algebraic Reconstruction Technique (ART) was used to formulate the system of algebraic equations [1-6, 8-10] solved by Singular Value Decomposition (SVD) [7].…”

“…The discretisation model with circle space elements [12,14,15] instead of classical square pixels or cuboid voxels simplifies numerical calculations on the one hand [13], but on the other hand causes complications. Under assumption that the rays have infinitely thin, some rays passing through square pixels or cubic voxels do not pass through their circularspherical equivalents.…”

The Chances of Precision Enhance for Ultrasonic Imaging

“…The first approach depends on the solution of the underdetermined system of equations with the aid of FOCUSS algorithm [4]. On the base of numerical experiments, one can say [16], that too deep under-determination of the system of equations has a bad influence on the quality of the solution. One can expect nice results if the number of unknowns is less than two times bigger than the number of observations.…”

“…Theoretical basis of developed algorithm interested readers could find in the monography [6]. Some interesting details are presented in the paper [16]. It is worth to stress that according to the simplifying assumptions the reflection rays will not be taken into account.…”