This paper deals with mathematical models of magnetic hysteresis implemented by assembling hysterons of play and stop type. A procedure for the identification of these models is described, and their behaviors are compared to experimental results. A comparison to the Preisach and Prandtl-Ishlinskii models is performed.:It is shown that the Play-Type Model is a possible alternative to Preisach's algorithm, whereas the Stop-Type Model is apt to represent the inverse of Preisach's operator. Simulations adopting both models are reported and compared to experimental data, Moreover, an application to the analysis of a ferroresonant circuit is studied, both numerically and experimentally

PACS. 41.20.Cv Electrostatics; Piezoelectricity and electrostriction,

In this paper the equivalent sources methods, written in terms both of the actual and of the external field, are used for the computation of the total force in two-dimensional axisymmetric problems. A Finite Element modeling of the magnetizing currents as field sources is presented in order to improve the formulations using the external field. The numerical accuracy of all the proposed formulae is thoroughly checked on linear and nonlinear test examples.

Summary. --A phenomenological model which represents a possible alternative to the well-known Preisach's model of magnetic hysteresis is here presented. The main feature of the proposed model, which differentiates it from Preisach's one, is that the individual elementary ,~particles,, are not themselves hysteretic; it is the mechanism by which the state of these particles is modified that introduces hysteretic behaviour. The model appears to be computationally less cumbersome than Preisach's one, while having the same application range.PACS 74.20 -Superconductivity. Theory.

The paper presents a thermodynamic derivation of the most general expressions for the force density, the electromagnetic surface traction, and the polarization work in an electrically or magnetically polarized solid, which is totally based on a continuum description. The notion of internal stress in polarized materials is discussed.PACS 77.60 -Piezoelectricity and electrostriction. PACS 75.80 -Magnetomechanical and magnetoelectric effects, magnetostriction. PACS 83.20 -Constitutive relations.