All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 2 Next

Displaying 21 – 40 of 48

Showing per page

On some composite schemes of time integration in structural dynamics

Vala, Jiří (2019)

Programs and Algorithms of Numerical Mathematics

Numerical simulations of time-dependent behaviour of advances structures need the analysis of systems of partial differential equations of hyperbolic type, whose semi-discretization, using the Fourier multiplicative decomposition together with the finite element or similar techniques, leads to large sparse systems of ordinary differential equations. Effective and robust methods for numerical evaluation of their solutions in particular time steps are required; thus still new computational schemes...

On the Cauchy problem in linear viscoelasticity

Pasquale Renno (1983)

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

Con riferimento all’operatore integrodifferenziale della viscoelasticità lineare nella formulazione creep, si determina la soluzione fondamentale E in corrispondenza di un’arbitraria funzione di memoria. Di conseguenza viene risolto esplicitamente il problema di Cauchy relativo al moto unidimensionale di un sistema viscoelastico ℬ , omogeneo ed isotropo, determinato da dati iniziali e storia di stress comunque prefissati. Successivamente, nell’ambito di opportune ipotesi di memoria labile, si dimostrano...

On the domain of influence in thermoelasticity of bodies with voids

Marin Marin (1997)

Archivum Mathematicum

The domain of influence, proposed by Cowin and Nunziato, is extended to cover the thermoelasticity of bodies with voids. We prove that for a finite time t > 0 the displacement field u i , the temperature θ and the change in volume fraction σ generate no disturbance outside a bounded domain B t .

On the dynamical behaviour of plates in unilateral contact with an elastic foundation: a finite element approach.

Luigi Ascione, Domenico Bruno, Renato S. Olivito (1984)

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

In questo lavoro viene studiato il comportamento dinamico di una piastra vincolata monolateralmente su una fondazione elastica alla Winkler. Si presentano alcuni risultati numerici ottenuti mediante discretizzazione agli elementi finiti. Tali risultati mettono in luce l'influenza di alcuni fattori tipici come le funzioni di forma, il parametro di mesh e l'ampiezza dell'intervallo con cui si realizza l'integrazione nel tempo delle equazioni del moto. Si istituiscono infine dei confronti con risultati...

On the history of suspension bridge theory

T. Malcolm Charlton, Placido Cicala (1991)

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

A linearized formulation of the elastic theory of suspension bridges is confronted with early investigations in the field. For decades, the structure was schematized as a beam (deck or girder) relieved by a one parameter distribution of forces exerted by the cable, disregarding the influence of beam deflection on that distribution as given by the linearized approach. An anonymous note presented the essential conclusions of this theory anticipating results of investigations following the methods...

On the mechanical behaviour of laminated curved beams: a simple model which takes into account the warping effects

Luigi Ascione, Fernando Fraternali (1990)

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

A mechanical one-dimensional model which describes the dynamical behaviour of laminated curved beams is formulated. It is assumed that each lamina can be regarded as a Timoshenko's beam and that the rotations of the cross sections can differ from one lamina to another. The relative displacements at the interfaces of adjacent laminae are assumed to be zero. Consequently the model includes a shear deformability, due to the warping of the cross beam section consequent to the variability of the laminae...

On the optimal control problem governed by the equations of von Kármán. II. Mixed boundary conditions

Igor Bock, Ivan Hlaváček, Ján Lovíšek (1985)

Aplikace matematiky

A control of the system of Kármán's equations for a thin elastic plate is considered. Existence of an optimal transversal load and optimal stress function, respectively, is proven. The set of admissible functions is chosen in a way guaranteeing the unique solvability of the state problem. The differentiability of the state function with respect to the control variable, uniqueness of the optimal control and some necessary conditions of optimality are discussed.

On the optimal control problem governed by the equations of von Kármán. I. The homogeneous Dirichlet boundary conditions

Igor Bock, Ivan Hlaváček, Ján Lovíšek (1984)

Aplikace matematiky

A control of the system of nonlinear Kármán's equations for a thin elastic plate with clamped edge is considered. The transversal loading plays the role of the control variable. The set of admissible controls is chosen in a way guaranteeing the unique solvability of the state function with respect to the control variable is proved. A disscussion of uniqueness of the optimal control and some necessary conditions of optimality are presented.

On the solution of boundary value problems for sandwich plates

Igor Bock, Ivan Hlaváček, Ján Lovíšek (1986)

Aplikace matematiky

A mathematical model of the equilibrium problem of elastic sandwich plates is established. Using the theory of inequalities of Korn's type for a general class of elliptic systems the existence and uniqueness of a variational solution is proved.

Currently displaying 21 – 40 of 48