Effect of gravity on visco-elastic surface waves in solids involving time rate of strain and stress of higher order.
Effect of imperfections and damping on the type of nonlinearity of circular plates and shallow spherical shells.
Effective computation of restoring force vector in finite element method
We introduce a new way of computation of time dependent partial differential equations using hybrid method FEM in space and FDM in time domain and explicit computational scheme. The key idea is quick transformation of standard basis functions into new simple basis functions. This new way is used for better computational efficiency. We explain this way of computation on an example of elastodynamic equation using quadrilateral elements. However, the method can be used for more types of elements and...
Effects of In-plane Elastic Stress and Normal External Stress on Viscoelastic Thin Film Stability
Motivated by recent experiments on the electro-hydrodynamic instability of spin-cast polymer films, we study the undulation instability of a thin viscoelastic polymer film under in-plane stress and in the presence of either a close by contactor or an electric field, both inducing a normal stress on the film surface. We find that the in-plane stress affects both the typical timescale of the instability and the unstable wavelengths. The film stability...
Effects of variations in nonlinear damping coefficients on the parametric vibration of a cantilever beam with a lumped mass.
Efficient application of e-invariants in finite element method for an elastodynamic equation
We introduce a new efficient way of computation of partial differential equations using a hybrid method composed from FEM in space and FDM in time domain. The overall computational scheme is explicit in time. The key idea of the suggested way is based on a transformation of standard basis functions into new basis functions. The results of this matrix transformation are e-invariants (effective invariants) with such suitable properties which save the number of arithmetical operations needed for a...
Eigenfrequencies of generally restrained beams.
Eigenvalue approximations by mixed methods
Elastic wave propagation in parallel: the Huygens' approach.
The use of parallel computers makes it feasible to simulate elastic waves throughout large heterogeneous structures, and new domain decomposition methods can be used to increase their efficiency and decrease the computing time spent in the simulation. In this paper we introduce a simple parallel algorithm for the propagation of elastic waves in complex heterogeneous media after a finite element discretization. This method performs more efficiently than classic domain decomposition techniques based...
Elastodynamic singular points and their applications.
Energy methods for curved composite beams with partial shear interaction
This paper presents a derivation of the Rayleigh- Betti reciprocity relation for layered curved composite beams with interlayer slip. The principle of minimum of potential energy is also formulated for two-layer curved composite beams and its applications are illustrated by numerical examples. The solution of the presented problems are obtained by the Ritz method. The applications of the Rayleigh-Betti reciprocity relation proven are illustrated by some examples.
Energy of the harmonics in a vibrating string after the impact of a hammer
In questa Nota vengono usati alcuni risultati precedentemente ottenuti - v. [4] e [5] - riguardanti l'urto di un martelletto rigido e di una corda elastica. Da essi possono dedursi le condizioni della corda - deformazione e atto di moto - all'istante in cui essa rimane libera dall'influenza del martelletto. È dunque possibile determinare mediante l'analisi di Fourier, i valori delle energie delle varie armoniche, i quali, com'è ben noto, determinano il timbro del suono emesso dalla corda (timbro...
Engergy decay for the quasilinear wave equation with viscosity.
Erratum of article “Reduced-order Unscented Kalman Filtering with application to parameter identification in large-dimensional systems”
Erratum of article “Reduced-order Unscented Kalman Filtering with application to parameter identification in large-dimensional systems”
Esistenza e unicità della soluzione nella statica di solidi termoelastici incomprimibili
In this work we prove that the thermoelastic equilibrium problem in the context of the linear theory for thermoelastic incompressible solids has one and only one solution.
Estensione a leggi costitutive a variabili interne dei teoremi di inadattamento in dinamica strutturale elastoplastica
Si considera il problema del mancato adattamento in campo dinamico per strutture elasto-plastiche incrudenti. Si dimostrano una condizione necessaria ed una sufficiente per il verificarsi di fenomeni di inadattamento (plasticità alternata o collasso incrementale) estendendo risultati precedenti ad un'ampia classe di modelli costitutivi a variabili interne in grado di rappresentare comportamenti incrudenti non lineari.
Étude d'un modèle hyperbolique en dynamique des câbles
Exact controllability of vibrations of thin bodies.
Existence and asymptotic stability for viscoelastic problems with nonlocal boundary dissipation
We consider the damped semilinear viscoelastic wave equation with nonlocal boundary dissipation. The existence of global solutions is proved by means of the Faedo-Galerkin method and the uniform decay rate of the energy is obtained by following the perturbed energy method provided that the kernel of the memory decays exponentially.