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This paper aims to study unstructured-partial element equivalent circuit (PEEC) method for modelling electromagnetic regions with surface impedance condition (SIBC) is proposed. Two coupled circuits representations are used for solving both electric and/or magnetic effects in thin regions discretized by a finite element surface mesh. The formulation is applied in the context of low frequency problems with volumic magnetic media and coils. Non simply connected regions are treated with fundamental branch independent loop matrices coming from the circuit representation.

Because of the use of Whitney face elements, two coupled circuits representations are used for solving both electric and/or magnetic effects in thin regions discretized by a finite element surface mesh. The air is not meshed.

The new surface impedance formulation enables the modeling of volume conductive regions to efficiently simulate various devices with only a surface mesh.

The propagation effects are not taken into account in the proposed formulation.

The formulation is original and is efficient for modeling non simply connected conductive regions with the use of SIBC. The unstructured PEEC SIBC formulation has been validated in presence of volume magnetic nonconductive region and compared with a SIBC FEM approach. The computational effort is considerably reduced in comparison with volume approaches.

The purpose of this paper is to present a design method for induction machines including a three-phase damper winding for noise and vibrations reduction.

In the first part, the principle of the damper winding is recalled. The second part presents the iterative design method which is applied on a 4-kW pulse width modulation (PWM)-fed induction machine to study the impact of the additional winding on the geometry. In the third part, the finite-element method is used to validate the designed geometry and highlight the harmonic flux density reduction. Finally, some experimental results are given.

The study shows that the impact of the additional three-phase winding on the geometry and weight of the machine is low. Moreover, the proposed noise reduction method allows one to reduce the total noise level of a PWM-fed induction machine up to 8.5 dBA.

The originality of the paper concerns the design and characterization of a three-phase damper winding for a noiseless induction machine. The principle of this proposed noise reduction method is new and has been patented.

The present article analyses the effects of cross-border mergers and acquisitions (CBM&As) on targets' total factor productivity (TFP), employment, wages and intangible-asset investment. The author investigates whether the impact of CBM&As differs depending on the origin of the investing multinational (MNE). The author distinguishes between CBM&As from European countries, other developed countries and emerging countries.

The author makes use of a unique firm-level data set of foreign direct investment in the French manufacturing sector. The authors applies propensity score matching and difference in differences to estimate the effect of CBM&As.

The results show that the consequences of CBM&As differ strongly depending on the origin. CBM&As from European MNEs have a positive impact on TFP, wages and intangible-asset investment, and those from emerging countries seem to increase wages and intangible-asset investments. In contrast, CBM&As that originate from MNEs from other developed countries do not have a significant effect.

This article contributes to the growing literature on the effects of foreign direct investment that highlights the relevance of accounting for the MNEs' origin. In particular, it is the first to address the impact of emerging-country MNEs' CBM&As in Europe.

This paper presents a computer‐aided design (CAD) tool for the design of isolated dc‐dc converters.

This tool, developed in Matlab environment, is based on multiobjective optimization (MO) using genetic algorithms. The Elitist Nondominated Sorting Genetic Algorithm is used to perform search and optimization whereas analytical models are used to model the power converters. The design problem requires minimizing the weight, losses and cost of the converter while ensuring the satisfaction of a number of constraints. The optimization variables are, as for them, the operating frequency, the current density, the maximum flux density, the transformer dimensions, the wire diameter, the core material, the conductor material, the converter topology (among Flyback, Forward, Push‐Pull, half‐bridge and full‐bridge topologies), the number of semiconductor devices associated in parallel, the number of cells associated in series or parallel as well as the kinds of input and output connections (serial or parallel) of these cells. Finally, the design of an auxiliary railway power supply is presented and discussed.

The results show that such tool to design dc‐dc power converters presents several advantages. In particular, it proposes to the designer a set of solutions – instead of a single one – so that he can choose a posteriori which solution best fits the application under consideration. Moreover, interesting solutions not considered a priori can be found with this tool.

To the best of the authors’ knowledge, such a CAD tool including a MO procedure taking several topologies into account has not been suggested so far.