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Showing 1 to 14 of 14 for “"Iterative reconstruction algorithms"”.
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Iterative Reconstruction Algorithms for Polyenergetic X-ray Computerized Tomography
A reconstruction algorithm in computerized tomography is a procedure for reconstructing the attenuation coefficientscient, a real-valued function associated with the object of interest, from the measured projection data. Generally speaking, reconstruction algorithms in CT fall into two categories: …
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Modeling and Development of Iterative Reconstruction Algorithms in Emerging X-ray Imaging Technologies
… radiation doses associated with use of analytic reconstruction methods in DPCT, we analyze the numerical and statistical properties of two classes of discrete imaging models that form the basis for iterative image reconstruction. Secondly, to improve image quality in grating-based phase-contrast …
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The Software and Hardware Acceleration for Interior Tomography
… and high-speed imaging characteristic. The iterative reconstruction algorithms are becoming more important since they can reconstruct better image qualities from incomplete projection data compared to analytical reconstruction algorithms. Iterative reconstruction algorithms also allow more …
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Fast Backprojection Algorithms for Divergent Beam Tomography
The use of hierarchical backprojection algorithms in divergent beam tomography is found to have good image quality while providing a speedup of 10--80 times over the conventional backprojection algorithm. These fast algorithms will be important when moving to higher resolution images or utilizing …
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Reconstruction of Functions From Non-uniformly Distributed Sampled Data in Shift-Invariant Frame Subspaces
… research is to study and implement efficient iterative reconstruction algorithms. Iterative reconstruction algorithms are used to reconstruct bandlimited signals in shift-invariant L2 subspaces from a set of non-uniformly distributed sampled data. The Shannon-Whittaker reconstruction formula …
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Algebraic Reconstruction Methods for Complex Geometry Components
… cabinet systems are capable of acquisition and reconstruction of Cone Beam CT (CBCT) data utilising reconstruction algorithms such as the FDK, which are mathematically based on traditional FBP. While these algorithms are computationally efficient, limitations in the acquisition make inspection …
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Development and Implementation of Fully 3D Statistical Image Reconstruction Algorithms for Helical CT and Half-Ring PET Insert System
… high computational cost, statistical iterative reconstruction algorithms are known to reconstruct high-quality images from noisy tomographic datasets. The overall goal of this work is to design statistical reconstruction software for clinical x-ray CT scanners, and for a novel PET …
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Iterative reconstruction as a novel method of radiation dose reduction at computed tomography in patients with Crohn's disease
… limitation with conventional CT raw data reconstruction was the inherent coupling of administered radiation dose with observed image noise – the lower the radiation dose, the noisier the image. The renaissance, rediscovery and refinement of iterative reconstruction removes this limitation …
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Optimization of image quality and radiation dose in neuroradiological computed tomography
… with new post-processing image filters and iterative reconstruction (IR) algorithms that improve image quality and allow for reduced radiation doses. Implementation of new methods in clinical routine requires prior validation in phantoms and clinical feasibility studies including …
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Development of Spect and Ct Tomographic Image Reconstruction
… to the advancement of statistically-based iterative reconstruction algorithms and protocols for both SPECT and micro CT data. Major contributions of this work to SPECT reconstruction include formulation and implementation of fully three-dimensional voxel-based system matrix in …
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System Optimization and Iterative Image Reconstruction in Photoacoustic Computed Tomography for Breast Imaging
… (3D) object such as the breast, iterative reconstruction algorithms are often utilized to alleviate the need to collect densely sampled measurement data hence a long scanning time. However, the heavy computation burden associated with iterative algorithms largely hinders its …
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The Reconstruction of Binary Images in Discrete Tomography by Using the Binary Steering Scheme
<p>We propose and study the reconstruction of large binary images in discrete tomography (DT) by applying the binary steering scheme to the block-iterative projections methods for solving an underdetermined linear system Ax = b. Three algorithms: Algebraic Reconstruction Technique (ART) Algorithm, …
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Robust Treatment Planning and Robustness Evaluation for Proton Therapy of Head and Neck Cancer
… the patient CT dose such as dual-energy CT and iterative reconstruction algorithms, are needed to confirm the presented findings. Additionally, the aRO approach applied to other body sites and entities might also be investigated. In near future, further in-room imaging methods such as cone-beam …
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Development of stopping rule methods for the MLEM and OSEM algorithms used in PET image reconstruction
… of stopping rule methods for the MLEM and OSEM algorithms used in image reconstruction positron emission tomography (PET). The development of the stopping rules is based on the study of the properties of both algorithms. Analyzing their mathematical expressions, it can be observed that the pixel …