in this paper we study isotropic lagrangian submanifolds , in complex space forms . it is shown that they are either totally geodesic or minimal in the complex projective space , if . when , they are either totally geodesic or minimal in . we also give a classification of semi-parallel lagrangian h-umbilical submanifolds.

The stability theories energetically associated with different finite strain measures are equivalent if the tangential moduli are transformed as a function of the stress. However, for homogenized soft-in-shear composites, they can differ greatly if the material is in small-strain and constant elastic moduli measured in small-strain tests are used. Only one theory can then be correct. The preced...

W present a new adaptive reconnection-based arbitrary Lagrangian Eulerian: A-ReALE method. The main elements in a A-ReALE method are: An explicit Lagrangian phase on arbitrary polygonal mesh in which the solution and positions of grid nodes are updated; a rezoning phase in which a new grid is defined number of mesh cells, their location and connectivity (it is based on using Voronoi tessellatio...

A micro/nano-scale computational contact mechanics model is proposed to study the adhesive contact between deformable bodies. To model adhesive contact, an interatomic interaction potential is incorporated into the framework of nonlinear continuum mechanics. The ensuing contact model is cast into an efficient finite element formulation which is implemented using an updated Lagrangian approach. ...

A technique for maintaining the positive definiteness of the matrices in the quasi-Newton version of the SQP algorithm is proposed. In our algorithm, matrices approximating the Hessian of the augmented Lagrangian are updated. The positive definiteness of these matrices in the space tangent to the constraint manifold is ensured by a so-called piecewise line-search technique, while their positive...

A novel non-linearly explicit second-order accurate L-stable computational methodology for integrating the non-linear equations of motion without non-linear iterations during each time step, and the underlying implementation procedure is described. Emphasis is placed on illustrative non-linear structural dynamics problems employing both total/updated Lagrangian formulations to handle finite def...

We propose an efficient numerical algorithm for computing deformations of ‘very’ soft tissues (such as the brain, liver, kidney etc.), with applications to real-time surgical simulation. The algorithm is based on the finite element method using the total Lagrangian formulation, where stresses and strains are measured with respect to the original configuration. This choice allows for pre-computi...

Augmented Lagrangian methods are effective tools for solving large-scale nonlinear programming problems. At each outer iteration a minimization subproblem with simple constraints, whose objective function depends on updated Lagrange multipliers and penalty parameters, is approximately solved. When the penalty parameter becomes very large the subproblem is difficult, therefore the effectiveness ...

We present an updated analysis of meson-baryon sigma terms in the per-turbative chiral quark model, which is based on effective chiral Lagrangian. The new feature concerns the inclusion of excited states in the quark prop-agator. Its influence on meson loops is shown to lead in particular for the pion-nucleon sigma term to an enhancement relevant for the current evaluation of this quantity. We ...

In this work we address the problem of numerically simulating the Friction Stir Welding process. Due to the special characteristics of this welding method (i.e., high speed of the rotating pin, very large deformations, etc.) finite element methods encounter several difficulties. Meshless methods somewhat alleviate this problems, allowing for an updated Lagrangian framework in the simulation. Ac...