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A magnetostriction phenomenological model able to include the effects of varying mechanical load is presented. The model exploits the formalism of the classical Preisach model and is therefore easy to implement, well behaved, and easy to identify. Experimental results over a real actuator showing the promising performances of the approach are provided. Index Terms--Actuators, hysteresis, internal stress, magnetostriction.

In this paper, the design of the one-cycle controller of a single-stage inverter for photovoltaic applications is carried out by means of a multiobjective strategy to optimize inverter performance at both high and low insolation levels. Design constraints that account for different weather conditions are adopted. The optimization algorithm also provides useful information concerning the system sensitivity with respect to each of the controller parameters. This allows the design of a maximum power point tracking perturb and observe controller that significantly improves inverter performance. Experimental measurements confirm the predictions of theoretical and simulation results. Index Terms--Maximum power point tracking (MPPT) techniques, one-cycle control (OCC), photovoltaic (PV) inverter.

This paper proposes the analysis and application of the Preisach inverse, which is implemented in a very simple fashion, and allows applying them easily into electromagnetic codes formulated in terms of a vector potential. Such an algorithm has been proposed in real-time control of hysteretic systems but never in the numerical analysis of devices employing ferromagnetic materials. Such a model has also been compared to other Preisach-based models. Their properties are briefly discussed and accurate analyses of their performances are reported, both in terms of accuracy and computational efficiency. Index Terms--Inverse, Preisach model, pseudoinverse.

This paper analyzes the performances of an embedded closed-loop control system with a compensated magnetostrictive actuator (e.g., a Terfenol-D based device) for micropositioning tasks. The control system and the compensation algorithm are implemented, as a standalone application, on a microcontroller. The embedded application and its performance in terms of tracking error reduction is evaluated with respect to both open and closed loop configurations. The uncompensated case is used as a reference. Index Terms--Compensation, feedback, hysteresis, magnetostrictive actuators.

The banking crises which have affected a number of industrial nations and the financial problems they encountered were examined from the perspectives of international finance, the economics of regulation and public policy. It was concluded that proper internal and external governance does not ensure complete stability in banking. Market discipline may falter if market participants do not have sufficient information. While additional regulatory arrangements are called for in market failures, the protection which they provide should be evaluated and the economic costs of bail-outs should not be excessive.

The article discusses a recently devised device, which can be employed for the magnetostrictive energy harvesting purpose from environmental vibrations. Several other models that can be used for the same purpose are also presented.

The generalization of a stress-dependent magnetostriction phenomenological model, which has used a classical Preisach operator and a memoryless bivariate function, is described. It is shown that the operator is affected by the applied stress even if the structure of the model is simple and this property is important as the model can catch real magnetostrictive behavior in the presence of complex time evolutions of both the variables, current and stress.

A model is used for describing the energy harvesting in magnetostriction devices and the effects of hysteresis are highlighted and compared to the predictions of the linear modeling. The coupling of the model to the circuit equations has led to the differential equation with hysteresis and numerical tests are conducted to show the effect of a magnetic field bias on the generated electric power.

Background: Cardiac magnetic resonance (CMR) is essential for diagnosing cardiomyopathy, serving as the gold standard for assessing heart chamber volumes and tissue characterization. Hemodynamic forces (HDF) analysis, a novel approach using standard cine CMR images, estimates energy exchange between the left ventricular (LV) wall and blood. While prior research has focused on peak or mean longitudinal HDF values, this study aims to investigate whether unsupervised clustering of HDF curves can identify clinically significant patterns and stratify cardiovascular risk in non-ischemic LV cardiomyopathy (NILVC)., Methods and Results: A retrospective cohort of 279 patients with NILVC who underwent cardiac CMR at Vall d'Hebron University Hospital (Barcelona) was examined. Unsupervised clustering of longitudinal and transversal HDF curves was performed using Dynamic Time Warping for dissimilarity measurement and the Partitioning Around Medoids algorithm. Outcomes were defined as a composite of cardiovascular mortality, heart failure hospitalization, and ventricular arrhythmias. Median age was 65[57.0;74.0] years, with 27.2% females and 35.5% showing late gadolinium enhancement (LGE). Unsupervised clustering identified three distinct clusters, delineating risk groups with worsening LA and LV function, indicating a stepwise increase in cardiovascular risk profile. Over a median follow-up of 40 months, 60 patients experienced the composite outcome. After adjusting for LGE, LVEF and LV size, clusters 2 and 3 demonstrated a significantly higher risk of adverse events (both p<0.05) compared to cluster 1., Conclusion: Analyzing both longitudinal and transversal HDF throughout the cardiac cycle enables the identification of distinct phenotypes with prognostic value beyond ejection fraction and LGE in NILVC patients., (© The Author(s) 2025. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)