Search results for "DAMP"
showing 10 items of 260 documents
Promuovere l’inclusione attraverso il Programma Motorio Abilità Diverse
2023
Gli studi svolti nell’ambito delle neuroscienze, delle scienze motorie e le conseguenti applicazioni didattiche, hanno posto in evidenza la necessità di avviare processi di progettazione e organizzazione dei contenuti, delle modalità organizzative e delle metodologie in educazione fisica e nell’avviamento allo sport, per integrare e modulare fattori inerenti la quantità inclusiva e promuovere pratiche adattive e preventive per raggiungere sempre più persone con diverse esigenze. Le politiche nazionali e sovranazionali, attraverso il PNRR, sottolineano come l’educazione motoria rivesta un ruolo privilegiato per contrastare i fenomeni dell’esclusione e della marginalizzazione, nel periodo com…
Parameter tuning for nacelle-based passive structural control of a spar-type floating wind turbine
2013
This paper deals with the modeling and parameter tuning of a spar-type floating wind turbine with a tuned mass damper (TMD) installed in nacelle. Firstly, a mathematical model for the system surge-heave-pitch motion is established based on first principles. Secondly, different parameter tuning methods are adopted to find the optimal TMD parameters for load reduction. Thirdly, nonlinear wind turbine simulations with different designs are conducted under different wind and wave conditions. The results show that TMD with small spring and damping coefficients will help to produce much load reduction in above rated condition. However, it may deteriorate system performance when the turbine is wor…
Elements Design of the Equipment for the Closing of Shock Absorbers through the Rolling Method
2015
The objective of this paper is the design of some elements of equipment for the closing of shock absorbers through the rolling method with a wide range of tank tube lengths and also of the functional structure of the equipment with the shifting/settlement of the damper in the sertization process. Closing damper device is intended by the deflection of the upper reservoir tube. In the paper, the author present his concerns regarding the study and design (parts CAD, the crimping devices) of this equipment which use this proposed technology [1, 2] for the crimping rolling method for shock absorbers reservoir cylinders.
MODELING TORQUE TRANSMISSIBILITY FOR AUTOMOTIVE DRY CLUTCH ENGAGEMENT
2008
The dry clutch is a fundamental component in many automotive drivelines. For instance, the clutch torque transmissibility characteristic severely influences gearshift performance in automated manual transmissions. In this paper a novel model of the torque transmissibility of dry clutches is proposed. The dependence of the transmissibility characteristic on wear, slip speed and friction pads geometry and the influence of the diaphragm spring, the flat spring and the torsional damper springs is taken into account and pointed out. The sensitivity of a clutch engagement control scheme with respect to the clutch characteristic uncertainties is analyzed.
Probabilistic response of linear structures equipped with nonlinear dampers devices (PIS method)
2008
Passive control introducing energy absorbing devices into the structure has received considerable attention in recent years. Unfortunately the constitutive law of viscous fluid dampers is highly nonlinear, and even supposing that the structure behaves linearly, the whole system has inherent nonlinear properties. Usually the analysis is performed by a stochastic linearization technique (SLT) determining a linear system equivalent to the nonlinear one, in a statistical sense. In this paper the effect of the non-Gaussianity of the response due to the inherent nonlinearity of the damper device will be studied in detail via the Path Integral Solution (PIS) method. A systematic study is conducted…
Lock-In Signal Post-Processing Techniques in Infra-Red Thermography for Materials Structural Evaluation
2013
This paper describes the potential of off-line thermographic signal processing by means of Lock-In Correlation algorithms, in order to implement structural health monitoring and stress analysis techniques. Thermal datasets acquired by infrared thermocameras are locked-in and correlated numerically with opportune reference signals, and amplitude and phase values of various harmonics retrieved by means of a Fast Fourier Transform and time averaging based filtering. This information is then processed for NDT defect probing and for evaluating the Thermoelastic Effect induced temperature changes. Two case studies in particular are discussed, implementing the proposed signal lock-in processing: a…
Quantitative thermoelastic stress analysis by means of low-cost setups
2020
Abstract A low-cost Thermoelastic Stress Analysis (TSA) experimental setup is proposed which uses an ordinary micro-bolometer and in-house developed signal processing scripts. The setup is evaluated by analysing the thermoelastic signal from a tensile and a SENT specimen made of stainless steel AISI 304L, and the bolometer performances are compared with those of a state of the art photon detector. Signal processing is based on off-line cross-correlation, using a self-reference signal which is retrieved from the acquired thermal data. Procedures are in particular developed to recognise, quantify and correct errors due to spectral leakage and loss of streamed frames. The thermoelastic signal …
A FEM piezoelectric beam model for damping circuit analysis
2013
A finite element, developed for straight generally layered smart beam, is used to investigate vibration damping capability of circuit elements. First, the electric state is analytically condensed to kinematical quantities and the mechanical model is then written for shear deformable Timoshenko’s beam including the effects of electro-elastic couplings stacking sequence. The contributions of the external electric loads on both the equivalent stiffness properties and the equivalent mechanical boundary conditions are also taken into account. The finite element is formulated by using Hermite shape functions, which depend on parameters representative of the staking sequence through the equivalent…
Modified Landau levels, damped harmonic oscillator and two-dimensional pseudo-bosons
2010
In a series of recent papers one of us has analyzed in some details a class of elementary excitations called {\em pseudo-bosons}. They arise from a special deformation of the canonical commutation relation $[a,a^\dagger]=\1$, which is replaced by $[a,b]=\1$, with $b$ not necessarily equal to $a^\dagger$. Here, after a two-dimensional extension of the general framework, we apply the theory to a generalized version of the two-dimensional Hamiltonian describing Landau levels. Moreover, for this system, we discuss coherent states and we deduce a resolution of the identity. We also consider a different class of examples arising from a classical system, i.e. a damped harmonic oscillator.
Non-stationary pre-envelope covariances of non-classically damped systems
1991
Abstract A new formulation is given to evaluate the stationary and non-stationary response of linear non-classically damped systems subjected to multi-correlated non-separable Gaussian input processes. This formulation is based on a new and more suitable definition of the impulse response function matrix for such systems. It is shown that, when using this definition, the stochastic response of non-classically damped systems involves the evaluation of quantities similar to those of classically damped ones. Furthermore, considerations about non-stationary cross-covariances, spectral moments and pre-envelope cross-covariances are presented for a monocorrelated input process.