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Deformable models in medical image analysis: a survey

Tim McInerney, Demetri Terzopoulos
1996 Medical Image Analysis  
shape representation, matching, and motion tracking.  ...  They have proven to be effective in segmenting, matching, and tracking anatomic structures by exploiting (bottom-up) constraints derived from the image data together with (top-down) a priori knowledge  ...  TM is grateful for the financial support of an NSERC postgraduate scholarship. DT is a fellow of the Canadian Institute for Advanced Research.  ... 
doi:10.1016/s1361-8415(96)80007-7 pmid:9873923 fatcat:pb3ros6vcbdhte4ifj7xnbqnfe

Magnetic resonance measurement of transient shear wave propagation in a viscoelastic gel cylinder

P.V. Bayly, P.G. Massouros, E. Christoforou, A. Sabet, G.M. Genin
2008 Journal of the mechanics and physics of solids  
The technique employs tagged magnetic resonance imaging (MRI) synchronized to periodic impact excitation of a bulk specimen.  ...  A magnetic resonance measurement technique was developed to characterize the transient mechanical response of a gel cylinder subjected to angular acceleration.  ...  Hood, and Richard Nagel for technical support.  ... 
doi:10.1016/j.jmps.2007.10.012 pmid:18568090 pmcid:PMC2435052 fatcat:ajuv3vbhffanfnsqkb5e3lmugi

MRI-based technique for determining nonuniform deformations throughout the volume of articular cartilage explants

C.P. Neu, M.L. Hull, J.H. Walton, M.H. Buonocore
2005 Magnetic Resonance in Medicine  
The custom pulse sequence incorporated the "delays alternating with nutations for tailored excitation" (DANTE) pulse sequence to apply tags.  ...  The error analysis using the phantom material indicated that deformations can be determined with an error, defined as the strain precision, better than 0.83% strain.  ...  Marc Geers, Eindhoven University of Technology, The Netherlands, for providing his custom strain measurement code, and Laura Melton for her assistance in harvesting the cartilage explant.  ... 
doi:10.1002/mrm.20343 pmid:15678528 fatcat:xx35ft6lkzecpka5kqksvlvbc4

Automatic alignment of standard views in 3D echocardiograms using real-time tracking

Fredrik Orderud, Hans Torp, Stein Inge Rabben, Stephen A. McAleavey, Jan D'hooge
2009 Medical Imaging 2009: Ultrasonic Imaging and Signal Processing  
The main goal of this thesis has been to explore the possibilities of using state estimation methods for segmentation and tracking of structures in volumetric data with deformable models.  ...  The ability of using non-iterative estimators, such as the Kalman filter, for fitting deformable models to image structures would radically reduce the computationally effort required for performing a 3D  ...  and Technology (NTNU) for access to the datasets used.  ... 
doi:10.1117/12.805380 fatcat:yyzsi6dvsrhclhmqjo5axjigqi

A remeshed vortex method for mixed rigid/soft body fluid–structure interaction [article]

Yashraj Bhosale, Tejaswin Parthasarathy, Mattia Gazzola
2020 arXiv   pre-print
We outline a 2D algorithm for solving incompressible flow--structure interaction problems for mixed rigid/soft body representations, within a consistent framework based on the remeshed vortex method.  ...  Through these illustrations, we showcase the ability of our solver to robustly deal with different constitutive models and boundary conditions, solve disparate multi-physics problems and achieve faster  ...  CBET-1846752 (MG) and by the Blue Waters project (OCI-0725070, ACI-1238993), a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications.  ... 
arXiv:2011.09669v1 fatcat:reqh4fmylzfirarfax3vwtiuby

Chaotic mixing and transport in wavy Taylor–Couette flow

Alp Akonur, Richard M. Lueptow
2002 Physica D : Non-linear phenomena  
The results show how mixing is enhanced with increasing rotating Reynolds number as a consequence of increased stretching and folding that occurs in meridional, latitudinal, and circumferential surfaces  ...  The axial particle transport increases with the rotating Reynolds number as a consequence of stretching and folding within the vortices and the axial transport between vortices, both related to the waviness  ...  In order to validate the particle tracking code, particles were tracked in a mathematically generated velocity field that was mapped on to a three-dimensional polar grid with spacing similar to the experimental  ... 
doi:10.1016/s0167-2789(02)00529-8 fatcat:h5rsidv6mbfofdt2oh2kzxcfwi

Robustness of target dose coverage to motion uncertainties for scanned carbon ion beam tracking therapy of moving tumors

John Gordon Eley, Wayne David Newhauser, Daniel Richter, Robert Lüchtenborg, Nami Saito, Christoph Bert
2015 Physics in Medicine and Biology  
We modeled various deviations from perfect tracking that could arise due to uncertainty in organ motion and limited precision of a scanned ion beam tracking system.  ...  To accomplish this, we simulated beam tracking for moving targets in both water phantoms and a sample of lung cancer patients using a research treatment planning system.  ...  Acknowledgments We thank George Starkschall for helpful scientific discussions regarding uncertainties in lung motion.  ... 
doi:10.1088/0031-9155/60/4/1717 pmid:25650520 pmcid:PMC4384336 fatcat:jowfrujdrjds7fxqfrtx7mdjeq

Quantitative Imaging Methods for the Development and Validation of Brain Biomechanics Models

Philip V. Bayly, Erik H. Clayton, Guy M. Genin
2012 Annual Review of Biomedical Engineering  
Modeling and simulation hold promise for illuminating the mechanisms of traumatic brain injury (TBI) and for developing preventive devices and strategies.  ...  First, they must capture the biomechanics of the brain as both a material and a structure, including the mechanics of brain tissue and its interactions with the skull.  ...  Owing to limited space, this review omits many relevant studies; we regret and apologize for these omissions. LITERATURE CITED  ... 
doi:10.1146/annurev-bioeng-071811-150032 pmid:22655600 pmcid:PMC3711121 fatcat:47s3wfpuuvdbdkjvarssnxsidq

Evolution of an eroding cylinder in single and lattice arrangements

James N. Hewett, Mathieu Sellier
2017 Journal of Fluids and Structures  
A cylinder is then modelled within an infinite array of other cylinders by simulating a repeating unit cell and their profile evolution is studied.  ...  A similar terminal form is discovered for large cylinder spacings with consistent flow conditions and an intermediate profile was found with a closely packed lattice before reaching the common terminal  ...  Figure 2 : 2 Lattice of cylinders are shown for both the (a) sparsely spaced (L/2a 0 = 8) and (b) closely packed (L/2a 0 = 4) configurations with their respective repeating computational unit cells used  ... 
doi:10.1016/j.jfluidstructs.2017.01.011 fatcat:bbumvrvknbfgzkb3kxjxqssomm

Recent developments in single-molecule DNA mechanics

Zev Bryant, Florian C Oberstrass, Aakash Basu
2012 Current Opinion in Structural Biology  
Acknowledgements We thank Jan Lipfert, Maxim Sheinin, Ralf Seidel, Mark Bathe, Erwin Peterman, Hendrik Dietz, and John Marko for helpful discussions and for providing data and images.  ...  A.B. is supported by a Stanford Bio-X graduate fellowship, F.C.O. is supported by a Swiss National Science Foundation fellowship, and Z.B. is supported by a Pew Scholars Award.  ...  Extension is measured from the focal depth z, while angle is measured by tracking xy motion constrained to a circular orbit about the DNA axis.  ... 
doi:10.1016/ pmid:22658779 pmcid:PMC3726534 fatcat:fzoxs55fczcfpg5ha66q3ttrrm

The flow-induced vibration of an elliptical cross-section at varying angles of attack

J.S. Leontini, M.D. Griffith, D. Lo Jacono, J. Sheridan
2018 Journal of Fluids and Structures  
This aspect ratio is large enough so that the deformation from a circular cylinder is obvious, but not so large that the geometry is not related to the cylinder.  ...  However, for large angles, where the body is far from symmetric with respect to the wake centreline, the flow can be markedly different with distinct asymmetric modes, including one which is period-doubled  ...  Thompson for providing the spectral-element code used for the simulations.  ... 
doi:10.1016/j.jfluidstructs.2017.12.013 fatcat:54davvzydvf4te7ktrzoynnqce

Starting flow through nozzles with temporally variable exit diameter

2005 Journal of Fluid Mechanics  
A dimensionless temporal parameter is derived in order to track the vortex formation process for the various classes of nozzle motion.  ...  Kinematic models of the starting flows are used to accurately predict the fluid circulation produced by the vortex generators, and to emphasize the special role of the nozzle boundary layer in dictating  ...  The authors acknowledge enlightening and informative discussions with M. H. Dickinson, M. Milano, T. S. Pottebaum, A. E. Staples and J. J. Allen. We also thank  ... 
doi:10.1017/s002211200500515x fatcat:43vekdhyrrgghjbvhtn22tt2yi

On the Mechanism of Large Amplitude Flapping of Inverted Foil in a Uniform Flow [article]

P. S. Gurugubelli, R. K. Jaiman
2017 arXiv   pre-print
An elastic foil interacting with a uniform flow with its trailing edge clamped, also known as the inverted foil, exhibits a wide range of complex self-induced flapping regimes such as large amplitude flapping  ...  Due to the absence of vortex shedding process in the low-Re regime, the inverted foil no longer exhibits the periodic flapping.  ...  The LAF of inverted foil with a splitter closely resemble the VIV of an elastically mounted circular cylinder.  ... 
arXiv:1711.01065v1 fatcat:ee6fnyj3yjbf5ogoybjimnccja

Shape from depth discontinuities under orthographic projection

Douglas Lanman, Daniel Cabrini Hauagge, Gabriel Taubin
2009 2009 IEEE 12th International Conference on Computer Vision Workshops, ICCV Workshops  
We present a new method for reconstructing the 3-D surface of an opaque object from the motion of its depth discontinuities, when viewed under orthographic projection as the object undergoes rigid rotation  ...  A novel shape completion scheme is introduced to fill in gaps in the recovered surface, which would otherwise be impossible to reconstruct from the motion of the depth discontinuities alone.  ...  For this model, consider the case of a cylinder of radius r separated from the rotation axis by a distance R (with its symmetry axis parallel to the rotation axis).  ... 
doi:10.1109/iccvw.2009.5457427 dblp:conf/iccvw/LanmanHT09 fatcat:w3uqlls77jcanliqh3e2gqq75i

Simulation of the Doi–Edwards model in complex flow

A. P. G. van Heel, M. A. Hulsen, B. H. A. A. van den Brule
1999 Journal of rheology  
Synopsis The Doi-Edwards model is simulated in startup of two-dimensional complex flow. The flow geometry is that of a cylinder confined between two parallel plates.  ...  The second method is a new method which is introduced in this paper. We refer to this approach as the deformation field method. Theoretically the methods are equivalent.  ...  The Doi-Edwards model does not lead to a closed-form equation for the stress tensor.  ... 
doi:10.1122/1.551022 fatcat:5p5irkooonfjpn7bccxiv2ldla
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