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Page 7862 of Mathematical Reviews Vol. , Issue 99k [page]

1999 Mathematical Reviews  
The author discusses how the qualities of box splines can be utilized for image reconstruction in computerized tomography.  ...  Summary: “The quadratic geometric Hermite interpolant (GHI) as introduced by K. H. HOllig and J. Koch [Comput. Aided Geom.  ... 

A geometric approach to quadratic optimization: an improved method for solving strongly underdetermined systems in CT§

Dan Gordon, Rawia Mansour
2007 Inverse Problems in Science and Engineering  
The problem of image reconstruction from projections in computerized tomography, when cast as a system of linear equations, leads to an inconsistent system.  ...  Hence, a common approach to this problem is to seek a solution that minimizes some optimization criterion, such as minimization of the residual (least-squares solution) by quadratic optimization.  ...  Acknowledgments The authors wish to thank Rachel Gordon for her help and advice. Thanks are also due to the anonymous reviewers for their helpful comments.  ... 
doi:10.1080/17415970600952078 fatcat:gljw6giuurhlvpb7xutqzv47ty

Parameter optimization of relaxed Ordered Subsets Pre-computed Back Projection (BP) based Penalized-Likelihood (OS-PPL) reconstruction in limited-angle X-ray tomography

Shiyu Xu, Henri Schurz, Ying Chen
2013 Computerized Medical Imaging and Graphics  
A Pre-computed Back Projection based Penalized-Likelihood (PPL) method is proposed in the strategy to generate consistent image quality.  ...  This paper presents a two-step strategy to provide a quality-predictable image reconstruction.  ...  Part of the simulation and algorithm implementations in this paper is based on their previous work. This work is supported by grant NIH/NCI R01 CA134598-01A1.  ... 
doi:10.1016/j.compmedimag.2013.04.005 pmid:23707552 fatcat:vmdpbqm4ejgqniwow22rpfwpxa

Page 3609 of Mathematical Reviews Vol. , Issue 90F [page]

1990 Mathematical Reviews  
This technique is seen to be analogous to the back projection technique of D. E. Kuhl and R. Q. Edwards [Radiology 91 (1968), no. 5, 975-983] used in computerized tomography.  ...  In particular, point sets on an a xb grid are treated. Also, in this case, the algorithm is shown to be not optimal in the general BDTM.  ... 

Tomography by Fourier synthesis [article]

Pierre Maréchal, Abdelhadi Elasmai
2014 arXiv   pre-print
We consider a particular approach to the regularization of the inverse problem of computerized tomography. This approach is based on notions pertaining to Fourier synthesis.  ...  It refines previous contributions, in which the preprocessing of the data was performed according to the Fourier slice theorem.  ...  Finally, in Section 4, we prove the numerical feasibility of our approach by means of reconstructions in emission tomography, in which the evolution towards realistic projectors made it necessary to give  ... 
arXiv:1401.7456v1 fatcat:dz7dgrhnzzblre6fa47z57a7ce

Automatic Extraction of Complex 3D Structures Application to the Inner Ear Segmentation from Cone Beam CT Digital Volumes [article]

Florian Beguet, Jean-Luc Mari, Thierry Cresson, Matthieu Schmittbuhl, Jacques A. De Guise
2018 Eurographics Workshop on 3D Object Retrieval, EG 3DOR  
A geometric rigid adjustment allows a close fit to inner ear boundaries. Finally, a Laplacian mesh deformation method is used to iteratively refine the mesh.  ...  We apply this approach to the inner ear reconstruction of Cone Beam CT(CBCT) 3D data. The proposed method is based on a single prior shape initialization followed by two steps.  ...  However, Cone beam computerized tomography (CBCT) presents the advantage of having a shorter acquisition time and a higher spatial resolution while exposing patients to less ionizing radiation than conventional  ... 
doi:10.2312/3dor.20181048 fatcat:mxabvm76f5ag5du6p3bnkqhodq

The role of medical physicists and the AAPM in the development of treatment planning and optimization

Colin G. Orton, Thomas R. Bortfeld, Andrzej Niemierko, Jan Unkelbach
2008 Medical Physics (Lancaster)  
It is shown that medical physicists have played a vital role in the creation of innovative treatment planning techniques throughout the past century, most significantly since the advent of computerized  ...  tomography for three-dimensional ͑3D͒ imaging and high-powered computers capable of 3D planning and optimization.  ...  One can, therefore, say that medical physicists have used computerized optimization in IMRT as a tool to handle the large number of variables.  ... 
doi:10.1118/1.2990777 pmid:19070225 fatcat:qy5eonozfrbejnvpibk2a32ppu

Computerized Generation and Finite Element Stress Analysis of Endodontic Rotary Files

Victor Roda-Casanova, Álvaro Zubizarreta-Macho, Francisco Sanchez-Marin, Óscar Alonso Ezpeleta, Alberto Albaladejo Martínez, Agustín Galparsoro Catalán
2021 Applied Sciences  
In this study, an automated procedure is proposed for the computerized generation and finite element analysis of endodontic rotary files under bending and torsional conditions.  ...  Conclusions: The automated procedure allows an accurate description of the geometry of the endodontic file to be obtained based on its design parameters as well as a finite element model of the endodontic  ...  In another approach [22] , the geometry of the endodontic file is obtained from a tomography scanner.  ... 
doi:10.3390/app11104329 fatcat:2p732yva3nejhiann4hkdjwuj4

FittingC2Continuous Parametric Surfaces to Frontiers Delimiting Physiologic Structures

Jason D. Bayer, Matthew Epstein, Jacques Beaumont
2014 Computational and Mathematical Methods in Medicine  
Process performance is assessed with the reconstruction of a geometric model of mouse heart ventricles from a computerized tomography scan.  ...  We present a technique to fitC2continuous parametric surfaces to scattered geometric data points forming frontiers delimiting physiologic structures in segmented images.  ...  BCS110013 to Jacques Beaumont, and in part by the French Government through the Agence National de la Recherche (http://www .agence-nationale-recherche.fr/) program "Investissements d'avenir" with Grant  ... 
doi:10.1155/2014/278479 pmid:24782911 pmcid:PMC3982317 fatcat:3mkjh4l4rnbc3loc5z256p73wa

A Memetic Algorithm for Binary Image Reconstruction [chapter]

Vito Di Gesù, Giosuè Lo Bosco, Filippo Millonzi, Cesare Valenti
2008 Lecture Notes in Computer Science  
The algorithm generates by network flows a set of initial images according to two of the input projections and lets them evolve toward a solution that can be optimal or close to the optimum.  ...  Switch and compactness operators improve the quality of the reconstructed images which belong to a given generation, while the selection of the best image addresses the evolution to an optimal output.  ...  Introduction Discrete tomography (DT) is a particular case of computerized tomography that deals with structures which have a few internal density values (usually a couple), and sometimes it is possible  ... 
doi:10.1007/978-3-540-78275-9_34 fatcat:dgkz7rg5bfh2zkav4wqalszabi

From analytic inversion to contemporary IMRT optimization: Radiation therapy planning revisited from a mathematical perspective

Yair Censor, Jan Unkelbach
2012 Physica medica (Testo stampato)  
This 1 builds a bridge from historic work on IMRT planning to contemporary research in the context of Intensity-Modulated Arc Therapy (IMAT).  ...  In the second part of the paper, we review another fundamental question which has been subject to debate from the beginning of IMRT until the present day: The rotation therapy approach versus fixed angle  ...  We are grateful to the anonymous referees whose insightful comments on earlier versions helped us to improve this paper and to the Editor Fridtjof Nüsslin for his unusual encouragement throughout the evaluation  ... 
doi:10.1016/j.ejmp.2011.04.002 pmid:21616694 pmcid:PMC3164927 fatcat:i4hrzfkpzndbho7cgolsm2bqka

Cost- and time-effective three-dimensional bone-shape reconstruction from X-ray images

Murat Gunay, Mun-Bo Shim, Kenji Shimada
2007 International Journal of Medical Robotics and Computer Assisted Surgery  
The sequential quadratic programming (SQP) is used to solve this multi-dimentional optimization problem.  ...  Conventionally such shape data is extracted from volumetric data sets, obtained by three-dimensional sensors, such as computerized tomography (CT) and magnetic resonance imaging (MRI).  ...  Acknowledgements The authors would like to thank Mr Tomotake Furuhata, Research Associate at the Computer Integrated Engineering Laboratory, for his continuous support and technical assistance; and Dr  ... 
doi:10.1002/rcs.162 pmid:18200623 fatcat:bberepkmejavfisfzhhsntlvsu

STRESS ANALYSIS OF THE RADIAL HEAD REPLACEMENT IN AN ELBOW ARTICULATION

P. Hlavon, V. Fuis, T. Navrat, Z. Florian
2007 Journal of Biomechanics  
The influence of friction and material characteristics of bone tissue and cartilage on changes in contact pressure (and therefore to the abrasion) were analyzed using those models.  ...  The geometrical and computational models of radial head replacements and elbow joint were created.  ...  Acknowledgments At present, this project was supported and solved as a part of the grant by the Czech Science Foundation 101/05/0136 Clinical Biomechanical Problems of Big Human Joints, and research project  ... 
doi:10.1016/s0021-9290(07)70622-x fatcat:ygqpt5or6rgj5hrfw7gqb2jley

External fixator configurations in tibia fractures: 1D optimization and 3D analysis comparison

Luis M. Roseiro, M. Augusta Neto, Ana Amaro, Rogerio P. Leal, Miguel C. Samarra
2014 Computer Methods and Programs in Biomedicine  
Optimal design is performed with respect to the assembly of fixator components using a genetic algorithm.  ...  geometrical features can lead to an improvement on the stability of the external fixator.  ...  The 3D tibia geometry is obtained from a human tibia using computerized axial tomography (CAT Scan).  ... 
doi:10.1016/j.cmpb.2013.09.018 pmid:24176414 fatcat:vq575lqec5bg5dd6i3ok6drmka

Registration of renal SPECT and 2.5D US images

Francisco J. Galdames, Claudio A. Perez, Pablo A. Estévez, Claudio M. Held, Fabrice Jaillet, Gabriel Lobo, Gilda Donoso, Claudia Coll
2011 Computerized Medical Imaging and Graphics  
All exams were taken at the San Juan de Dios hospital in Santiago, Chile.  ...  The main goal of this study is the registration of renal SPECT (Single Photon Emission Computerized Tomography) and 2.5D US (Ultrasound) images.  ...  Levenberg-Marquardt algorithm, optimized by the distance transform, was used for the minimization of the quadratic distance.  ... 
doi:10.1016/j.compmedimag.2011.02.003 pmid:21371860 fatcat:k7ul6jrkgndhvfftor2ncaqnai
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