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An Accelerating Numerical Computation of the Diffusion Term in a Nonlocal Reaction-Diffusion Equation

Mitică CRAUS, Silviu-Dumitru PAVĂL
2020 Mathematics  
In this paper we propose and compare two methods to optimize the numerical computations for the diffusion term in a nonlocal formulation for a reaction-diffusion equation.  ...  While the first algorithm (sequential) is used as a baseline for performance measurement, the second algorithm (parallel) is implemented using two different memory-sharing parallelization technologies:  ...  method for a nonlocal reaction-diffusion model applied to a 2D input domain.  ... 
doi:10.3390/math8122111 fatcat:qmd35qskdbb2hm3ijvzrgtv6pi

Adaptively Tuned Iterative Low Dose CT Image Denoising

SayedMasoud Hashemi, Narinder S. Paul, Soosan Beheshti, Richard S. C. Cobbold
2015 Computational and Mathematical Methods in Medicine  
However, the parameter selection is typically performed in an ad hoc manner, which can cause the algorithms to converge slowly or become trapped in a local minimum.  ...  By combining NCRE with the fundamentals of block matching and 3D filtering (BM3D) approach, a new iterative CT image denoising method is proposed.  ...  The input for this step, which is a hard thresholding block, is the 3D noisy wavelet coefficients of similar patches located by block matching applied to the available noisy image.  ... 
doi:10.1155/2015/638568 pmid:26089972 pmcid:PMC4458284 fatcat:ljnw2t6aerh5laudegicqm7354

An interactive ImageJ plugin for semi-automated image denoising in electron microscopy

Joris Roels, Frank Vernaillen, Anna Kremer, Amanda Gonçalves, Jan Aelterman, Hiêp Q. Luong, Bart Goossens, Wilfried Philips, Saskia Lippens, Yvan Saeys
2020 Nature Communications  
The recent advent of 3D in electron microscopy (EM) has allowed for detection of nanometer resolution structures.  ...  We present DenoisEM: an interactive and GPU accelerated denoising plugin for ImageJ that ensures fast parameter tuning and processing through parallel computing.  ...  We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan X Pascal GPU used for this research.  ... 
doi:10.1038/s41467-020-14529-0 pmid:32034132 fatcat:zxioou6pw5hjhpnzbp6crmhvqm

Efficient Solutions for Nonlocal Diffusion Problems Via Boundary-Adapted Spectral Methods

Siavash Jafarzadeh, Adam Larios, Florin Bobaru
2020 Journal of Peridynamics and Nonlocal Modeling  
We introduce an efficient boundary-adapted spectral method for peridynamic transient diffusion problems with arbitrary boundary conditions.  ...  To test the performance of our approach we compare the computational results with analytical solutions of the nonlocal problem.  ...  Choosing the number of spatial nodes to be a power of two (N = 2 P ) has certain benefits in parallelization of FFT algorithms [44] .  ... 
doi:10.1007/s42102-019-00026-6 fatcat:ykqkg6vm5rdy7ez4libbafurfq

Nonlocal Regularized Algebraic Reconstruction Techniques for MRI: An Experimental Study

Xin Li
2013 Mathematical Problems in Engineering  
Using a continuous-to-discrete model, we experimentally study the application of ART into MRI reconstruction which unifies previous nonuniform-fast-Fourier-transform- (NUFFT-) based and gridding-based  ...  A resolution-consistent extension of NR-ART is developed and shown to effectively suppress the artifacts arising from frequency extrapolation.  ...  We do need a new nonlinear sampling theorem for the continuous-to-discrete model (in contrast to the one established for discrete-to-discrete model in CS theory [56, 57] ).  ... 
doi:10.1155/2013/192895 fatcat:h4qf22paorccnh4rrvhx4nzm7e

RGB-D Human Action Recognition of Deep Feature Enhancement and Fusion Using Two-Stream ConvNet

Yun Liu, Ruidi Ma, Hui Li, Chuanxu Wang, Ye Tao, Giovanni Diraco
2021 Journal of Sensors  
Proposed Nonlocal-stgcn (S-Stream) based on skeleton data, by adding nonlocal to obtain dependency relationship between a wider range of joints, to provide more rich skeleton point features for the model  ...  stream information is fused to realize action recognition.  ...  For time domain, the dilated settings for the slow and fast paths are 2 and 5; for spatial domain, it randomly crops 224 × 224 pixels from video.  ... 
doi:10.1155/2021/8864870 fatcat:rauuog3apfhvznytbp5v5uaexe

Digital Path Approach Despeckle Filter for Ultrasound Imaging and Video

Marek Szczepański, Krystian Radlak
2017 Journal of Healthcare Engineering  
domain.  ...  The experimental results prove that the proposed algorithm provides the comparable results with the state-of-the-art techniques for multiplicative noise removal in ultrasound images and it can be applied  ...  According to the works presented in [3] [4] [5] , one of the most promising results for ultrasound images was obtained with algorithms based on anisotropic diffusion techniques [6] and the idea of nonlocal  ... 
doi:10.1155/2017/9271251 pmid:29118965 pmcid:PMC5651154 fatcat:5hhg2pz7ynaztkw6rpugeylnzq

Nonlocal-Closure Schemes for Use in Air Quality and Environmental Models [chapter]

Dragutin Mihailovic, Ana Firanj
2010 Air Quality  
work described here has been funded by the Serbian Ministry of Science and Technology under the project "Study of climate change impact on environment: Monitoring of impact, adaptation and moderation", for  ...  When coupled to 3D models, single-column models can provide detailed and accurate simulations of the ABL structure as well as mixing processes.  ...  very similar to the ACM algorithm [Eqs  ... 
doi:10.5772/9759 fatcat:rpf7lo4eyfav3bs6v2sojsrsje

Computational modeling of pitting corrosion

Siavash Jafarzadeh, Ziguang Chen, Florin Bobaru
2019 Corrosion reviews  
This paper presents a critical review of the computational models for pitting corrosion.  ...  We conclude the paper with a discussion of open areas for future developments.  ...  in a discrete domain Peridynamic nonlocal diffusion equation Cahn-Hilliard equation Numerical method employed Mostly FEM FVM Algorithms based on transition rules Meshfree discretization  ... 
doi:10.1515/corrrev-2019-0049 fatcat:gr274w4xnjecxnlspldauwp6te

Denoising of DT-MR Images with an Iterative PCA

U. Sreelakshmi Priya, Jyothisha J. Nair
2015 Procedia Computer Science  
So our work aims to denoise the Diffusion Tensor MR images with better visual quality.  ...  During MR image acquisition the emitted energy is converted to image by using some mathematical models, and this may cause addition of noise. Therefore we need to denoise the image.  ...  ACKNOWLEDGMENT Our sincere gratitude to Dr. M.R Kaimal, Chairman, Department of Computer Science, for his valuable suggestions and also to Dr.  ... 
doi:10.1016/j.procs.2015.08.079 fatcat:dptqhcgwt5h23a6qos5oh5tdca

GPU-accelerated denoising of 3D magnetic resonance images

Mark Howison, E. Wes Bethel
2014 Journal of Real-Time Image Processing  
The raw computational power of GPU accelerators enables fast denoising of 3D MR images using bilateral filtering, anisotropic diffusion, and non-local means.  ...  And what tuning is necessary to achieve optimal performance on a modern GPU?  ...  Acknowledgements Thanks to Dani Ushizima, Alex Cunha, and Owen Carmichael for their comments and input on earlier versions of this study, and to D.  ... 
doi:10.1007/s11554-014-0436-8 fatcat:z7uv7fqlezgljpu5cvhu6h4sym

Efficient quadrature rules for finite element discretizations of nonlocal equations [article]

Eugenio Aulisa, Giacomo Capodaglio, Andrea Chierici, Marta D'Elia
2021 arXiv   pre-print
In this paper we design efficient quadrature rules for finite element discretizations of nonlocal diffusion problems with compactly supported kernel functions.  ...  Furthermore, we demonstrate the good scaling properties of the parallel implementation of the adaptive algorithm and we compare the proposed method with recently developed techniques for efficient finite  ...  These differences in memory allocation and CPU time indicate that a parallel implementation of the nonlocal assembly is vital to make nonlocal models a preferred and viable modeling option.  ... 
arXiv:2101.08825v1 fatcat:us7wjn4webfujjbrrmeplq25k4

Patch Group Based Nonlocal Self-Similarity Prior Learning for Image Denoising

Jun Xu, Lei Zhang, Wangmeng Zuo, David Zhang, Xiangchu Feng
2015 2015 IEEE International Conference on Computer Vision (ICCV)  
PGs are extracted from training images by putting nonlocal similar patches into groups, and a PG based Gaussian Mixture Model (PG-GMM) learning algorithm is developed to learn the NSS prior.  ...  In this paper, we propose a patch group (PG) based NSS prior learning scheme to learn explicit NSS models from natural images for high performance denoising.  ...  [12] constructed 3D cubes of nonlocal similar patches and conducted collaborative filtering in the sparse 3D transform domain.  ... 
doi:10.1109/iccv.2015.36 dblp:conf/iccv/XuZZZF15 fatcat:lvdqnp46qnhtvjqggic3tnd4oi

Induced homomorphism: Kirchhoff's law in photonics

Shuai Sun, Mario Miscuglio, Xiaoxuan Ma, Zhizhen Ma, Chen Shen, Engin Kayraklioglu, Jeffery Anderson, Tarek El Ghazawi, Volker J. Sorger
2021 Nanophotonics  
When solving, modeling or reasoning about complex problems, it is usually convenient to use the knowledge of a parallel physical system for representing it.  ...  Here, we argue that in absence of a straightforward parallelism a homomorphism can be induced.  ...  For mimicking a 3 × 3 FDM mesh a 5 × 5 photonic mesh is fabricated and tested, in which the additional nodes on the sides of the domain are used for reading/applying the optical power at the boundary.  ... 
doi:10.1515/nanoph-2020-0655 fatcat:krkytj4ef5a2bfagrbuj7m2vu4

Graphics processing units-accelerated adaptive nonlocal means filter for denoising three-dimensional Monte Carlo photon transport simulations

Yaoshen Yuan, Leiming Yu, Zafer Doğan, Qianqian Fang
2018 Journal of Biomedical Optics  
We develop a GPU-accelerated adaptive nonlocal means (ANLM) filter to denoise MC simulation outputs.  ...  The Monte Carlo (MC) method is widely recognized as the gold standard for modeling light propagation inside turbid media.  ...  Massively parallel MC algorithms have been proposed for simple homogeneous, 11 layered, 12 and threedimensional (3-D) heterogeneous media.  ... 
doi:10.1117/1.jbo.23.12.121618 pmid:30499265 pmcid:PMC7057723 fatcat:cbobqf3s25gmnaqgruxmjycu5m
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