Publications related to Stiffness matrix

Explicit Stabilized Multirate Method For Stiff Differential Equations

Stabilized Runge???Kutta methods are especially efficient for the numerical solution of large systems of stiff nonlinear differential equations because they are fully explicit. For semi-discrete parabolic problems, for instance, stabilized Runge???Kutta me ...

AMER MATHEMATICAL SOC2022

Explicit Stabilized Multirate Method For Stiff Stochastic Differential Equations

Assyr Abdulle, Giacomo Rosilho De Souza

Stabilized explicit methods are particularly efficient, for large systems of stiff stochastic differential equations (SDEs) due to their extended stability domain. However, they lose their efficiency when a severe stiffness is induced by very few "fast" de ...

SIAM PUBLICATIONS2022

Load cell with adjustable stiffness based on a preloaded T-shaped flexure pivot

Simon Nessim Henein, Charles Baur, Loïc Benoît Tissot-Daguette, Michal Stanislaw Smreczak

In this paper, we present a new flexure-based load cell with adjustable stiffness designed for force sensors with extended force range and respective measuring resolution. This novel monolithic mechanism consists of a T-shaped flexure pivot combined with a ...

euspen2021

Variable Stiffness Folding Joints for Haptic Feedback

Jamie Paik, Fabio Zuliani

Origami robots composed of rigid parts with flexible joints have inherent compliance that enables deployment and reconfiguration for various shape adaptations. The major drawback of such mechanical compliance is its intrinsic softness and lack of controlla ...

IEEE2021

Immersed boundary-conformal isogeometric method for linear elliptic problems

Annalisa Buffa, Pablo Antolin Sanchez, Xiaodong Wei

We present a novel isogeometric method, namely the Immersed Boundary-Conformal Method (IBCM), that features a layer of discretization conformal to the boundary while employing a simple background mesh for the remaining domain. In this manner, we leverage t ...

2021

Fast assembly of Galerkin matrices for 3D solid laminated composites using finite element and isogeometric discretizations

Pablo Antolin Sanchez

This work presents a novel methodology for speeding up the assembly of stiffness matrices for laminate composite 3D structures in the context of isogeometric and finite element discretizations. By splitting the involved terms into their in-plane and out-of ...

2020

A Computational Comparison Between Isogeometric Analysis and Spectral Element Methods: Accuracy and Spectral Properties

Alfio Quarteroni, Ondine Gabrielle Chanon

In this paper, we carry out a systematic comparison between the theoretical properties of Spectral Element Methods and NURBS-based Isogeometric Analysis in its basic form, that is in the framework of the Galerkin method, for the approximation of the Poisso ...

SPRINGER/PLENUM PUBLISHERS2020

Microstructural simulation and measurement of elastic modulus evolution of hydrating cement pastes

Karen Scrivener, Cyrille Dunant, Arnaud Charles Albert Muller, Arnaud Müller

Predicting the evolution of stiffness in cement paste requires linking morphological properties of the microstructure to the evolution of mechanical properties. Measures are typically difficult to obtain with sufficient time resolution to capture the trans ...

Pergamon-Elsevier Science Ltd2020

Elastic properties of self-organized nanogratings produced by femtosecond laser exposure of fused silica

Yves Bellouard, Pieter Vlugter

Under certain exposure conditions, a femtosecond laser beam focused in the bulk of fused silica leads to the formation of self-organized structures consisting of a series of “nanolayers,” parallel to one another. Remarkably, this laser-induced nanoscale an ...

2020

Random extrapolation for primal-dual coordinate descent

Volkan Cevher, Ahmet Alacaoglu

We introduce a randomly extrapolated primal-dual coordinate descent method that adapts to sparsity of the data matrix and the favorable structures of the objective function. Our method updates only a subset of primal and dual variables with sparse data, an ...

JMLR-JOURNAL MACHINE LEARNING RESEARCH2020

System and method for performing isogeometric analysis and finite element analysis using h-splines

Michaël Unser, Zsuzsanna Püspöki, Daniel Andreas Schmitter

A method for performing H-spline compatible isogeometric analysis (IGA) on a geometric object, the method being performed on a computer device having a memory, the method including the steps of creating an analysis suitable geometry (ASG) using H-splines f ...

2019

Reducing uncertainties in energy dissipation measurements in atomic force spectroscopy of molecular networks and cell-adhesion studies

Georg Fantner, Blake William Erickson, Soma Biswas, Samuel Mendes Leitão, Quentin Antoine Marie Theillaud

Atomic force microscope (AFM) based single molecule force spectroscopy (SMFS) is a valuable tool in biophysics to investigate the ligand-receptor interactions, cell adhesion and cell mechanics. However, the force spectroscopy data analysis needs to be done ...

Nature Research2018

An Analytical Model for Beam Flexure Modules Based on Timoshenko Beam Theory

Simon Nessim Henein, Mohammad Hussein Kahrobaiyan, Mohamed Gamal Abdelrahman Ahmed Zanaty

Short beams are the key building blocks in many compliant mechanisms. Hence, deriving a simple yet accurate model of their elastokinematics is an important issue. Since the Euler-Bernoulli beam theory fails to accurately model these beams, we use the Timos ...

2017

A new formulation for imposing Dirichlet boundary conditions on non-matching meshes

Jean-François Molinari, Alejandro Marcos Aragon, Aurelia Isabel Cuba Ramos

Generating matching meshes for problems with complex boundaries is often an intricate process, and the use of non-matching meshes appears as an appealing solution. Yet, enforcing boundary conditions on non-matching meshes is not a straightforward process, ...

Wiley-Blackwell2015

Printing low-voltage dielectric elastomer actuators

Herbert Shea, Samuel Rosset, Alexandre Poulin

We demonstrate the fabrication of fully printed thin dielectric elastomer actuators (DEAs), reducing the operation voltage below 300V while keeping good actuation strain. DEAs are soft actuators capable of strains greater than 100% and response times below ...

AIP American Institute of Physics2015

Magneto-mechanical actuation of ferromagnetic shape memory alloy/epoxy composites

Véronique Michaud, Susanne Glock, Luis Pablo Canal Casado

Ferromagnetic shape memory alloys (MSMA) exhibit magnetic field- and stress-induced twinning when processed into single crystals, but are brittle and difficult to shape. Embedding slender single crystalline MSMA elements into a polymer matrix can thus prov ...

2015

Mathematical modelling of active contraction in isolated cardiomyocytes

Alfio Quarteroni, Ricardo Esteban Ruiz Baier, Simone Rossi, Aymen Laadhari

We investigate the interaction of intracellular calcium spatio-temporal variations with the self-sustained contractions in cardiac myocytes. A consistent mathematical model is presented considering a hyperelastic description of the passive mechanical prope ...

Oxford University Press2014

Finite volume element approximation of an inhomogeneous Brusselator model with cross-diffusion

Ricardo Esteban Ruiz Baier

This paper is concerned with the study of pattern formation for an inhomogeneous Brusselator model with cross-diffusion, modeling an autocatalytic chemical reaction taking place in a three-dimensional domain. For the spatial discretization of the problem w ...

Elsevier2014

Convergence of quasi-optimal Stochastic Galerkin methods for a class of PDES with random coefficients

Fabio Nobile, Lorenzo Tamellini

In this work we consider quasi-optimal versions of the Stochastic Galerkin method for solving linear elliptic PDEs with stochastic coefficients. In particular, we consider the case of a finite number

N

of random inputs and an analytic dependence of the s ...

2014

An active strain electromechanical model for cardiac tissue

Alfio Quarteroni, Fabio Nobile, Ricardo Esteban Ruiz Baier

We propose a finite element approximation of a system of partial differential equations describing the coupling between the propagation of electrical potential and large deformations of the cardiac tissue. The underlying mathematical model is based on the ...

Wiley2012