Sökning: "Iterative reconstruction algorithms"
Visar resultat 1 - 5 av 16 avhandlingar innehållade orden Iterative reconstruction algorithms.
1. Combining analytical and iterative reconstruction in helical cone-beam CT
Sammanfattning : Contemporary algorithms employed for reconstruction of 3D volumes from helical cone beam projections are so called non-exact algorithms. This means that the reconstructed volumes contain artifacts irrespective of the detector resolution and number of projection angles employed in the process. LÄS MER
2. Algebraic Reconstruction Methods
Sammanfattning : Ill-posed sets of linear equations typically arise when discretizing certain types of integral transforms. A well known example is image reconstruction, which can be modeled using the Radon transform. After expanding the solution into a finite series of basis functions a large, sparse and ill-conditioned linear system occurs. LÄS MER
3. The Use of Landweber Algorithm in Image Reconstruction
Sammanfattning : Ill-posed sets of linear equations typically arise when discretizing certain types of integral transforms. A well known example is image reconstruction, which can be modelled using the Radon transform. After expanding the solution into a finite series of basis functions a large, sparse and ill-conditioned linear system arises. LÄS MER
4. Iterative Filtered Backprojection Methods for Helical Cone-Beam CT
Sammanfattning : State-of-the-art reconstruction algorithms for medical helical cone-beam Computed Tomography (CT) are of type non-exact Filtered Backprojection (FBP). They are attractive because of their simplicity and low computational cost, but they produce sub-optimal images with respect to artifacts, resolution, and noise. LÄS MER
5. Low kilovoltage computed tomography to reduce contrast medium dose in patients at risk of acute kidney injury
Sammanfattning : Background: Patients with reduced renal function may be at risk of contrast medium-induced acute kidney injury (CI-AKI) following intravenous iodine contrast medium (CM) enhanced computed tomography (CT). Reducing the CM dose may reduce this risk. LÄS MER