106 citations · 291 across the 16 of their papers we have counts for
17 papers
Uniqueness for Some Mixed Problems of Nonlinear Elastostatics
Phoebus Rosakis
We show that certain mixed displacement/traction problems (including live pressure tractions) of nonlinear elastostatics that are solved by a homogeneous deformation, admit no othe…
Sharp-interface limits for brittle fracture via the inverse-deformation formulation
Timothy J. Healey, Roberto Paroni, Phoebus Rosakis
We derive sharp-interface models for one-dimensional brittle fracture via the inverse-deformation approach. Methods of Gamma-convergence are employed to obtain the singular limits…
Compressive Instabilities Enable Cell-Induced Extreme Densification Patterns in the Fibrous Extracellular Matrix: Discrete Model Predictions
Chrysovalantou Kalaitzidou, Georgios Grekas, Andreas Zilian +2
Through modelling and simulations we show that material instabilities play a dominant role in the mechanical behavior of the fibrous collagen Extracellular Matrix (ECM), as observe…
A Deep Learning Approach to Nonconvex Energy Minimization for Martensitic Phase Transitions
Xiaoli Chen, Phoebus Rosakis, Zhizhang Wu +1
We propose a mesh-free method to solve nonconvex energy minimization problems for martensitic phase transitions and twinning in crystals, using the deep learning approach. These pr…
Machine Learning for the edge energies of high symmetry Au nanoparticles
Emmanouil Pervolarakis, Georgios A. Tritsaris, Phoebus Rosakis +1
We present data-driven simulations for gold nanostructures, and develop a model that links total energy to geometrical features of the particle, with the ultimate goal of deriving…
The inverse-deformation approach to fracture
Phoebus Rosakis, Timothy J. Healey, Ugur Alyanak
We propose a one-dimensional, nonconvex elastic constitutive model with higher gradients that can predict spontaneous fracture at a critical load via a bifurcation analysis. It ove…
Rethinking Case Fatality Ratios for COVID-19 from a data-driven viewpoint
Phoebus Rosakis, Maria Marketou
The case fatality ratio (CFR) for COVID-19 is difficult to estimate. One difficulty is due to ignoring or overestimating time delay between reporting and death. We claim that all o…
Approximations of energy minimization in cell-induced phase transitions of fibrous biomaterials: -convergence analysis
Georgios Grekas, Konstantinos Koumatos, Charalambos Makridakis +1
We consider a model of energy minimization arising in the study of the mechanical behavior caused by cell contraction within a fibrous biological medium. The macroscopic model is b…
Cells exploit a phase transition to mechanically remodel the fibrous extracellular matrix
Georgios Grekas, Maria Proestaki, Phoebus Rosakis +3
Through mechanical forces, biological cells remodel the surrounding collagen network, generating striking deformation patterns. Tethers-tracts of high densification and fiber align…
A Minimal Mechanosensing Model Predicts Keratocyte Evolution on Flexible Substrates
Zhiwen Zhang, Phoebus Rosakis, Thomas Y. Hou +1
A mathematical model is proposed for shape evolution and locomotion of fish epidermal keratocytes on elastic substrates. The model is based on mechanosensing concepts: cells apply…
The Interfacial Energy of a Phase Boundary via a Lattice-Cell Average Approach
Phoebus Rosakis
The calculation of the discrete atomistic energy of a crystal near the continuum limit encounters difficulties caused by the geometric discrepancy between the continuum region occu…
A Model for Compression-Weakening Materials and the Elastic Fields due to Contractile Cells
Phoebus Rosakis, Jacob Notbohm, Guruswami Ravichandran
We construct a homogeneous, nonlinear elastic constitutive law, that models aspects of the mechanical behavior of inhomogeneous fibrin networks. Fibers in such networks buckle when…
Microbuckling of Fibrin Provides a Mechanism for Cell Mechanosensing
Jacob Notbohm, Ayelet Lesman, Phoebus Rosakis +2
Biological cells sense and respond to mechanical forces, but how such a mechanosensing proccess takes place in a nonlinear inhomogeneous fibrous matrix remains unknown. We show tha…
On atomistic-to-continuum couplings without ghost forces in three dimensions
Charalambos Makridakis, Dimitrios Mitsoudis, Phoebus Rosakis
In this paper we construct energy based numerical methods free of ghost forces in three dimensional lattices arising in crystalline materials. The analysis hinges on establishing a…
New Solutions for Slow Moving Kinks in a Forced Frenkel-Kontorova Chain
Phoebus Rosakis, Anna Vainchtein
We construct new traveling wave solutions of moving kink type for a modified, driven, dynamic Frenkel-Kontorova model, representing dislocation motion under stress. Formal solution…
Continuum Surface Energy from a Lattice Model
Phoebus Rosakis
We investigate connections between the continuum and atomistic descriptions of deformable crystals, using certain interesting results from number theory. The energy of a deformed c…
Direct experimental measurement of the speed-stress relation for dislocations in a plasma crystal
V. Nosenko, G. E. Morfill, P. Rosakis
The speed-stress relation for gliding edge dislocations was experimentally measured for the first time. The experimental system used, a two-dimensional plasma crystal, allowed obse…