Search results for "classical"
showing 10 items of 2294 documents
An equivalent single-layer model for magnetoelectroelastic multilayered plate dynamics
2012
Abstract An equivalent single-layer model for the dynamic analysis of magnetoelectroelastic laminated plates is presented. The electric and magnetic fields are assumed to be quasi-static and the first-order shear deformation theory is used. The formulation of the model provides for a preliminary fulfillment of the electro-magnetic governing equations, which allows to determine the electric and magnetic potential as functions of the mechanical variables. Then, by using this result, the equations of motion are written leading to the problem governing equations. They involve the same terms of the elastic dynamic problem weighted by effective stiffness coefficients, which take the magneto-elect…
Nonlinear vibrations of elastic beams with external general visco-elastic devices
2011
Vibration damping for slender beams is achieved by applying devices at external points. The latter consist of general single visco-elastic springpot elements. An approximate nonlinear boundary value problem is found in frequency domain that holds for moderately large vibrations or for linear beams with external nonlinear devices, both in the vicinity of primary resonances. The interaction force of a so-called springpot element is expressed as a sum of two separate forces: the first develops due to the external loading function at the device location, and the second contribution arises due to an imposed time-harmonic support excitation with no other external forces acting on the structure. F…
Travelling Strings, Beams, Panels, Membranes and Plates
2013
In this chapter, we will introduce in a general manner some of the most common models for axially travelling materials, which will be used in the rest of the book. We will introduce the linear models of travelling strings, panels, and plates. It will be assumed that the material is thin, i.e. its planar dimensions are much larger than its thickness. We will work in the small displacement regime, that is, with linear models approximating the behaviour of the system near the trivial equilibrium. As is well known in the theory of elasticity, this approximation allows for a decoupling of the in-plane and out-of-plane components in the dynamics of the system. We will concentrate on small out-of-…
Effects of different lower-limb sensory stimulation strategies on postural regulation-a Systematic review and metaanalysis
2017
Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high-pooled effect sizes (Unbiased (Hedges' g) standardized mean differences (SMD) = 0.31-0.66) were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS), in three populations (i.e., healthy young adults, older adults, and individuals with low…
Bach fra le stelle
2014
Il testo costituisce la postfazione del volume di Ramin Bahrami "Il suono dell'Occidente. Le opere musicali che hanno fatto la nostra civiltà" (Mondadori 2014) e prende le mosse dal concetto di "Enciclopedia" per tracciare una riflessione storico-musicologica sulle 14 composizioni che Ramin Bahrami ssume quali imprescindibili punti di riferimento per una visione d'insieme della cultura musicale occidentale: da Monteverdi fino a Schoenberg, passando per Vivaldi, Bach, Wagner, Verdi, Mahler, Rakhmaninov e Stravnsky.
Spunti di classicismo nei monumenti siciliani ai caduti della Prima Guerra Mondiale
2021
Dopo la conclusione della Prima Guerra Mondiale, tutti i comuni italiani cominciarono a erigere monumenti celebrativi in onore dei soldati morti nell’immane conflitto. Un aspetto meritevole di speciale attenzione, in queste opere commemorative, è l’utilizzo molto rilevante di forme ed elementi derivati dall’antichità greca e romana. Singole iconografie e singoli schemi tipologici, opportunamente rielaborati, potevano infatti adattarsi anche ai nuovi contesti celebrativi e ne rafforzavano il significato. La Sicilia sembra essere un buon case study per mostrare le potenzialità di un’analisi di questo genere: nei centri abitati di questa regione, come in tutto il territorio nazionale, sono pre…
OpenMolcas: From Source Code to Insight
2019
In this article we describe the OpenMolcas environment and invite the computational chemistry community to collaborate. The open-source project already includes a large number of new developments realized during the transition from the commercial MOLCAS product to the open-source platform. The paper initially describes the technical details of the new software development platform. This is followed by brief presentations of many new methods, implementations, and features of the OpenMolcas program suite. These developments include novel wave function methods such as stochastic complete active space self-consistent field, density matrix renormalization group (DMRG) methods, and hybrid multico…
Fast relaxation phenomena and slow mode in extended thermodynamics of superfluids
2003
A macroscopic monofluid model of liquid helium II which is based on extended thermodynamics was formulated in previous works, both in the presence and in the absence of dissipative phenomena. In all these studies, the time evolution of the nonequilibrium stress tensor was neglected, putting the relaxation times @t"0 and @t"2 of the nonequilibrium pressure and of the stress deviator equal to zero. In this work, the time evolution of these fields is not neglected and the complete model with 14 fields is studied, in the linear approximation. The propagation of waves is studied and a dispersion relation of degree 14 is obtained. The solutions of this equation are carried out, perturbing the sol…
Spatio-temporal Characteristics of THz Emission at the Subwavelength Scale via Optical Rectification
2011
Highly localized THz emission via optical rectification in thin nonlinear crystals is a promising method for subwavelength microscopy. We present here the peculiar THz spatio-temporal characteristics induced by the non-paraxial generation regime.
Wave propagation in anisotropic turbulent superfluids
2013
In this work, a hydrodynamical model of Superfluid Turbulence previously formulated is applied to study how the presence of a non-isotropic turbulent vortex tangle modifies the propagation of waves. Two cases are considered: wave front parallel and orthogonal to the heat flux. Using a perturbation method, the first-order corrections due to the presence of the vortex tangle to the speeds and to the amplitudes of the first and second sound are determined. It is seen that the presence of the quantized vortices couples first and second sound, and the attenuation of second sound is proportional to the line density L if the wave propagates orthogonal to the heat flux, while it is proportional to …