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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.

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.)