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Mechanical aspects of growth in soft tissues

D. Ambrosi, F. Guana (2004)

Bollettino dell'Unione Matematica Italiana

In the last years many efforts have been devoted to understand the stressmodulated growth of soft tissues. Recent theoretical achievements suggest that a component of the stress-growth coupling is tissue-independent and reads as an Eshelby-like tensor. In this paper we investigate the mathematical properties and the qualitative behavior predicted by equations that specialize that model under few simple assumptions. Equations strictly deduced from a dissipation principle are compared with heuristic...

Mesh r-adaptation for unilateral contact problems

Pierre Béal, Jonas Koko, Rachid Touzani (2002)

International Journal of Applied Mathematics and Computer Science

We present a mesh adaptation method by node movement for two-dimensional linear elasticity problems with unilateral contact. The adaptation is based on a hierarchical estimator on finite element edges and the node displacement techniques use an analogy of the mesh topology with a spring network. We show, through numerical examples, the efficiency of the present adaptation method.

Mesoscopic description of boundary effects in nanoscale heat transport

F.X. Àlvarez, V.A. Cimmelli, D. Jou, A. Sellitto (2012)

Nanoscale Systems: Mathematical Modeling, Theory and Applications

We review some of the most important phenomena due to the phonon-wall collisions in nonlocal heat transport in nanosystems, and show how they may be described through certain slip boundary conditions in phonon hydrodynamics. Heat conduction in nanowires of different cross sections and in thin layers is analyzed, and the dependence of the thermal conductivity on the geometry, as well as on the roughness is pointed out. We also analyze the effects of the roughness of the surface of the pores on the...

Metodo della differenza ali'indietro e determinazione dei moduli tangenti per analisi evolutive elastoplastiche a passi finiti

Umberto Perego (1988)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

Si discute l'applicazione di un procedimento per "differenza all'indietro" ("backward difference") all'integrazione numerica nel tempo di leggi costitutive elastoplastiche e se ne esaminano alcuni aspetti peculiari. Con riferimento a modelli costitutivi isotropi per i quali le funzioni di snervamento dipendono dall'invariante primo delle tensioni, dall'invariante secondo del deviatore delle tensioni e da opportune variabili interne, si ricavano le relazioni non lineari implicite in termini di incrementi...

Microlocal analysis and seismic imaging

Christiaan Stolk (2003/2004)

Séminaire Équations aux dérivées partielles

We study certain Fourier integral operators arising in the inversion of data from reflection seismology.

Microscopic Modelling of Active Bacterial Suspensions

A. Decoene, S. Martin, B. Maury (2011)

Mathematical Modelling of Natural Phenomena

We present two-dimensional simulations of chemotactic self-propelled bacteria swimming in a viscous fluid. Self-propulsion is modelled by a couple of forces of same intensity and opposite direction applied on the rigid bacterial body and on an associated region in the fluid representing the flagellar bundle. The method for solving the fluid flow and the motion of the bacteria is based on a variational formulation written on the whole domain, strongly...

Minimization of a convex quadratic function subject to separable conical constraints in granular dynamics

Pospíšil, Lukáš, Dostál, Zdeněk (2015)

Programs and Algorithms of Numerical Mathematics

The numerical solution of granular dynamics problems with Coulomb friction leads to the problem of minimizing a convex quadratic function with semidefinite Hessian subject to a separable conical constraints. In this paper, we are interested in the numerical solution of this problem. We suggest a modification of an active-set optimal quadratic programming algorithm. The number of projection steps is decreased by using a projected Barzilai-Borwein method. In the numerical experiment, we compare our...

Minimizers with topological singularities in two dimensional elasticity

Xiaodong Yan, Jonathan Bevan (2008)

ESAIM: Control, Optimisation and Calculus of Variations

For a class of 2-D elastic energies we show that a radial equilibrium solution is the unique global minimizer in a subclass of all admissible maps. The boundary constraint is a double cover of S 1 ; the minimizer u is C 1 and is such that det u vanishes at one point.

Minimizers with topological singularities in two dimensional elasticity

Jonathan Bevan, Xiaodong Yan (2010)

ESAIM: Control, Optimisation and Calculus of Variations

For a class of 2-D elastic energies we show that a radial equilibrium solution is the unique global minimizer in a subclass of all admissible maps. The boundary constraint is a double cover of S1; the minimizer u is C1 and is such that det u vanishes at one point.


Currently displaying 41 – 60 of 114