Weak formulations in Analytical Dynamics are developed, paralleling the variational methods in elastostatics, and including a fundamental yet novel approach for treating constraints (both holonomic and nonholonomic). A general three-field approach is presented, in which the momentum balance conditions, the compatibility conditions between displacement and velocity, the constitutive relations an...

We present a family of pairs of finite element spaces for the unaltered Hellinger–Reissner variational principle using polynomial shape functions on a single triangular mesh for stress and displacement. There is a member of the family for each polynomial degree, beginning with degree two for the stress and degree one for the displacement, and each is stable and affords optimal order approximati...

in classical mechanics, considering hook’s law stress is a linear function of strain. while in strain gradient theory stress is a function of strain and strain differentials. in this paper, novel formulation relating stress and strain and also new boundary conditions are derived based on minimum potential energy principle. in strain gradient theory a length coefficient parameter is defined. thi...

This paper presents a novel hybrid FEM-based approach for nonlinear buckling analysis of truss with initial length imperfection. The contribution deals establishing two types finite element (perfection and imperfection element) considering large displacement based on formulation mixed formulation. Therefore, the global equation system is developed by assembling perfection elements. incremental-...

1. Abstract We propose a novel approach for the analysis of cohesive crack propagation in elastic media. Unlike all existing methods that move from continuous displacement formulations that are properly enriched to handle the discontinuity, see e.g. the extended finite element method (XFEM) or the embedded discontinuity approaches, inherently discontinuous displacements and H(div,Ω) stresses in...

A set of equilibrium equations for a biphasic polymer gel are considered with the end purpose of studying stress and deformation in confinement problems encountered in connection with biomedical implants. The existence of minimizers for the gel energy is established first. Further, the small-strain equations are derived and related to the linear elasticity equations with parameters dependent on...

the objective of the present study was to prepare controlled release formulation of moxifloxacin hydrochloride ocular nanoparticles. the nanoparticles were prepared by solvent displacement method using eudragit rl 100 as a polymer. different formulations were prepared by varying the ratios of drug and polymer and varying the ratios of organic and aqueous phase. the formulations were evaluated i...

A node-based smoothed finite element method (NS-FEM-T3) using triangular elements and a n-sided polygonal edge-based smoothed FEM (nES-FEM) using polygonal elements is combined to give the smoothed coupled NS/nES-FEM for dynamic analysis of twodimensional (2D) fluid–solid interaction problems based on the pressure–displacement formulation. In the present method, the NS-FEM-T3 is used for the fl...

A direct formulation of linear elasticity cell complexes based on discrete exterior calculus is presented. The primary unknowns are displacements, represented by a primal vector-valued 0 -cochain. Displacement differences and internal forces 1 -cochain dual 2 -cochain, respectively. macroscopic constitutive relation enforced at -cells with the help musical isomorphisms mapping cochains to smoot...