English
Related papers

Related papers: Least Squares Finite Element Method for Hepatic Si…

200 papers

Flow in fractured porous media represents a challenge for discretization methods due to the disparate scales and complex geometry. Herein we propose a new discretization, based on the mixed finite element method and mortar methods. Our…

Numerical Analysis · Mathematics 2017-07-18 Wietse M. Boon , Jan M. Nordbotten , Ivan Yotov

This paper studies a model of two-phase flow with an immersed material viscous interface and a finite element method for numerical solution of the resulting system of PDEs. The interaction between the bulk and surface media is characterized…

Numerical Analysis · Mathematics 2021-06-08 Maxim Olshanskii , Annalisa Quaini , Qi Sun

We propose a hemodynamic reduced-order model bridging macroscopic and meso-scopic blood flow circulation scales from arteries to capillaries. In silico tree like vascular geometries, mathematically described by graphs, are synthetically…

Medical Physics · Physics 2019-07-29 Olivier Adjoua , Stéphanie Pitre-Champagnat , Didier Lucor

Cerebral blood flow and perfusion can be estimated using tracer dilution experiments. Accurate estimation of blood flow parameters is a crucial part of medical imaging for effective diagnosis and treatment. This study explores two themes:…

Medical Physics · Physics 2024-02-29 Ishmael N. Amartey , Andreas A. Linninger , Thomas Ventimiglia

The increasing application of cardiorespiratory simulations for diagnosis and surgical planning necessitates the development of computational methods significantly faster than the current technology. To achieve this objective, we leverage…

Numerical Analysis · Mathematics 2024-03-21 Mahdi Esmaily , Dongjie Jia

In this study, we develop computational models and methodology for accurate multi-component-flow simulation in under-resolved multi-scale porous structures. It is generally impractical to fully resolve the flow in porous structures with…

We present a non-conforming least squares method for approximating solutions of second order elliptic problems with discontinuous coefficients. The method is based on a general Saddle Point Least Squares (SPLS) method introduced in previous…

Numerical Analysis · Mathematics 2019-04-01 Constantin Bacuta , Jacob Jacavage

Many studies regarding the vasculature of biological tissues involve the segmentation of the blood vessels in a sample followed by the creation of a graph structure to model the vasculature. The graph is then used to extract relevant…

Computer Vision and Pattern Recognition · Computer Science 2024-06-21 João Pedro Parella , Matheus Viana da Silva , Cesar Henrique Comin

It is shown that the computational efficiency of the discrete least-squares (DLS) approximation of solutions of stochastic elliptic PDEs is improved by incorporating a reduced-basis method into the DLS framework. The goal is to recover the…

Numerical Analysis · Mathematics 2017-11-09 Max Gunzburger , Michael Schneier , Clayton Webster , Guannan Zhang

Clinically useful proton Computed Tomography images will rely on algorithms to find the three-dimensional proton stopping power distribution that optimally fits the measured proton data. We present a least squares iterative method with many…

Medical Physics · Physics 2021-05-12 Don F. DeJongh , Ethan A. DeJongh

Least squares estimation, a regression technique based on minimisation of residuals, has been invaluable in bringing the best fit solutions to parameters in science and engineering. However, in dynamic environments such as in Geomatics…

Computational Engineering, Finance, and Science · Computer Science 2018-04-17 C. P. E. Agbachi

In this paper, we consider multipoint flux mixed finite element discretizations for slightly compressible Darcy flow in porous media. The methods are formulated on general meshes composed of triangles, quadrilaterals, tetrahedra or…

Numerical Analysis · Mathematics 2018-11-07 Andrés Arrarás , Laura Portero

A pore-scale model is introduced for two-phase flow in dense packings of polydisperse spheres. The model is developed as a component of a more general hydromechanical coupling framework based on the discrete element method, which will be…

Soft Condensed Matter · Physics 2016-01-06 Chao Yuan , Bruno Chareyre , Félix Darve

A new slender-body theory for viscous flow, based on the concepts of dimensional reduction and hyperviscous regularization, is presented. The geometry of flat, elongated, or point-like rigid bodies immersed in a viscous fluid is…

Fluid Dynamics · Physics 2016-03-23 Giulio G. Giusteri , Eliot Fried

Given a set of response observations for a parametrized dynamical system, we seek a parametrized dynamical model that will yield uniformly small response error over a range of parameter values yet has low order. Frequently, access to…

Numerical Analysis · Mathematics 2018-08-20 Alexander Grimm , Christopher Beattie , Zlatko Drmač , Serkan Gugercin

We present an algorithm for the numerical solution of the equations governing combustion in porous inert media. The discretization of the flow problem is performed by the mixed finite element method, the transport problems are discretized…

Numerical Analysis · Mathematics 2016-09-01 Peter Knabner , Gerhard Summ

An accurate steatosis quantification with pathology tissue samples is of high clinical importance. However, such pathology measurement is manually made in most clinical practices, subject to severe reader variability due to large sampling…

Computer Vision and Pattern Recognition · Computer Science 2018-06-26 Mousumi Roy , Fusheng Wang , George Teodoro , Miriam B Vos , Alton Brad Farris , Jun Kong

We provide a framework for the numerical approximation of distributed optimal control problems, based on least-squares finite element methods. Our proposed method simultaneously solves the state and adjoint equations and is $\inf$--$\sup$…

Numerical Analysis · Mathematics 2023-08-03 Thomas Führer , Michael Karkulik

We describe a simple Importance Sampling strategy for Monte Carlo simulations based on a least squares optimization procedure. With several numerical examples, we show that such Least Squares Importance Sampling (LSIS) provides efficiency…

Physics and Society · Physics 2008-12-10 Luca Capriotti

We are interested in a reduced order method for the efficient simulation of blood flow in arteries. The blood dynamics is modeled by means of the incompressible Navier-Stokes equations. Our algorithm is based on an approximated…

Numerical Analysis · Mathematics 2021-04-07 Luca Pegolotti , Martin Pfaller , Alison Marsden , Simone Deparis