63 research outputs found
Newton and Bouligand derivatives of the scalar play and stop operator
We prove that the play and the stop operator possess Newton and Bouligand
derivatives, and exhibit formulas for those derivatives. The remainder estimate
is given in a strenghtened form, and a corresponding chain rule is developed.
The construction of the Newton derivative ensures that the mappings involved
are measurable
Newton and Bouligand derivatives of the scalar play and stop operator
We prove that the play and the stop operator possess Newton and Bouligand derivatives, and exhibit formulas for those derivatives. The remainder estimate is given in a strengthened form, and a corresponding chain rule is developed. The construction of the Newton derivative ensures that the mappings involved are measurable
Hopf bifurcations and simple structures of periodic solution sets in systems with the Preisach nonlinearity
We survey a number of recent results and suggest some new ones on periodic solutions of systems with hysteresis. The main focus of this work is the situation when simple one-parameter structures of periodic regimes appear. We consider forced oscillations, cycles of autonomous systems and Hopf bifurcations from the equilibrium and from infinity
On the Mróz Model
We treat the mathematical properties of the one parameter version of the Mróz model for plastic flow. We present continuity results and an energy inequality for the hardening rule and discuss different versions of the flow rule regarding their relation to the second law of thermodynamics
Asymptotic stability of continual sets of periodic solutions to systems with hysteresis
We consider hysteresis perturbations of the system of ODEs which has an asymptotically stable periodic solution . It is proved that if the oscillation of the appropriate projection of is smaller than some threshold number defined by the hysteresis nonlinearity, then the perturbed system has a continuum of periodic solutions with a rather simple structure in a vicinity of . The main result is the theorem on stability of this continuum
Some analytical properties of the multidimensional continuous Mróz model of plasticity
We study the geometrical structure of memory induced by the continuous multidimensional Mr'oz model of plasticity. The results are used for proving the thermodynamic consistency of the model and composition and inversion formulas for input - memory state - output operators. We also show an example of nonuniqueness of solutions to a simple initial value problem involving the Mr'oz operator
Stochastic Hysteresis and Resonance in a Kinetic Ising System
We study hysteresis for a two-dimensional, spin-1/2, nearest-neighbor,
kinetic Ising ferromagnet in an oscillating field, using Monte Carlo
simulations and analytical theory. Attention is focused on small systems and
weak field amplitudes at a temperature below . For these restricted
parameters, the magnetization switches through random nucleation of a single
droplet of spins aligned with the applied field. We analyze the stochastic
hysteresis observed in this parameter regime, using time-dependent nucleation
theory and the theory of variable-rate Markov processes. The theory enables us
to accurately predict the results of extensive Monte Carlo simulations, without
the use of any adjustable parameters. The stochastic response is qualitatively
different from what is observed, either in mean-field models or in simulations
of larger spatially extended systems. We consider the frequency dependence of
the probability density for the hysteresis-loop area and show that its average
slowly crosses over to a logarithmic decay with frequency and amplitude for
asymptotically low frequencies. Both the average loop area and the
residence-time distributions for the magnetization show evidence of stochastic
resonance. We also demonstrate a connection between the residence-time
distributions and the power spectral densities of the magnetization time
series. In addition to their significance for the interpretation of recent
experiments in condensed-matter physics, including studies of switching in
ferromagnetic and ferroelectric nanoparticles and ultrathin films, our results
are relevant to the general theory of periodically driven arrays of coupled,
bistable systems with stochastic noise.Comment: 35 pages. Submitted to Phys. Rev. E Minor revisions to the text and
updated reference
On the Moving Preisach Model
It is shown that the moving model, which is a variant of the Preisach model for hysteresis, possesses the wiping out property and is continuous in C[0,T] under natural assumptions
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