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The purpose of this paper is to investigate the influence of measurement uncertainties and the environment characteristics themselves on the desired field uniformity (FU) in reverberation chambers (RCs) by means of state-of-the-art global sensitivity analysis techniques. There are many quantities to describe the FU. The authors attempted to inspect many of the most important ones in two different orientations of the stirrer (horizontal, vertical).

Surrogate modelling techniques are involved to compute the Sobol’ indices efficiently with a modest number of required electromagnetic (EM) simulations. This can be only achieved if the behaviour of an appropriately chosen output quantity is predictable in such a way, which enables to extract useful information. Therefore, this choice should be made with extra care of the stochastic fluctuations, which have to be as low as possible. To this end, in this paper, various figures of merit are investigated.

This method can provide useful knowledge in the lower frequency range, where the ideal properties of the EM field in RCs cannot be established, and the importance of the setup parameters can vary from configuration to configuration.

Considering the current research tendencies related to RCs, the application of the method of Sobol’ indices to RCs is unique, which has only been done by the authors of this work so far. The main contribution presented in the paper is the thorough investigation of the effect of configuration parameters on the statistical properties of RCs through many output quantities describing the FU.

Global sensitivity analysis (SA) by means of Sobol’ indices enhanced with different surrogate modeling techniques is performed in this work. The purpose is to investigate the influence of measurement uncertainties and the environment characteristics themselves on the desired field uniformity in reverberation chambers (RCs). This yields an efficient apparatus for the stirring and chamber design process.

The technique of Sobol’ indices, as a candidate of global SA methods, is suitable for high fluctuations due to its robustness, which can be addressed to the stochastic nature of the RC environment. The aim of using surrogate modeling techniques is to compute the indices efficiently with a moderate number of required simulations. The powerfulness of this approach is introduced in a simple numerical example in which the physical phenomena can be identified more straightforwardly.

This method can provide useful knowledge in the lower frequency range, where the ideal properties of the electromagnetic field in RCs cannot be established, and the importance of the setup parameters can vary from configuration to configuration. In addition, it can serve as a basis for setup adaptation during parallelized electromagnetic compatibility tests, which would result in a more time- and cost-saving option in industrial applications in the future.

Despite the previous attempts, a profound investigation of multiple setup parameters is still a hot topic. The main contribution of this work is the extension of the application area of the method of Sobol’ indices to RCs, which has not been done so far.

The electromagnetic modeling of inductively coupled, resonant wireless power transfer (WPT) is dealt with. This paper aims to present a numerically efficient simulation method.

Recently, integral equation formulations have been proposed, using piecewise constant basis functions for the series expansion of the current along the coil wire. In the present work, this scheme is improved by introducing global basis functions.

The use of global basis functions provides a stronger numerical stability and a better control over the convergence of the simulation; moreover, the associated computational cost is lower than for the previous schemes. These advantages are demonstrated in numerical examples, with special attention to the achievable efficiency of the power transfer.

The method can be efficiently used, e.g., in the optimal design of resonant WPT systems.

The presented computation scheme is original in the sense that global series expansion has not been previously applied to the numerical simulation of resonant WPT.

To propose a novel method for defect reconstruction in electromagnetic non‐destructive testing (NDT).

The inversion method is based on an optimized database that contains the measured signals for some predefined defect prototypes. The database is supported by an anisotropic simplex mesh, which has been generated adaptively in the abstract n‐dimensional space, spanned by the model parameters of the defect type. The actual reconstruction reduces to a mesh search and interpolation. The described theory is demonstrated in the paper by a solved NDT test problem.

We have realized that in addition to sole defect reconstruction, the database provides meta‐information about the quality of the inversion, the suitability of the chosen defect model parameters, as well as the capabilities of the testing experiment.

Defect models having several parameters require a sophisticated mesh generation algorithm, which works in higher dimensions.

In the authors' opinion the mesh database approach offers a totally new point of view of a given inverse problem, and may help in the better understanding of its nature.

The purpose of this paper is to provide a new methodology for the characterization of a defect by eddy‐current testing (ECT). The defect is embedded in a conductive non‐magnetic plate and the measured data are the impedance variation of an air‐cored probe coil scanning above the top of the plate.

The inverse problem of defect characterization is solved by an iterative global optimization process. The strategy of the iterations is the kriging‐based expected improvement (EI) global optimization algorithm. The forward problem is solved numerically, using a volume integral approach.

The proposed method seems to be efficient in the light of the presented numerical results. Further investigation and comparison to other methods are still needed.

This is believed to be the first time when the EI algorithm has been used to solve an inverse problem related to the ECT.

The purpose of this paper is to present a novel eddy-current modeling technique of volumetric defects embedded in conducting plates. This problem is of great interest in electromagnetic non-destructive evaluation and has already been exhaustively studied.

The defect is modeled by a volumetric current dipole density which satisfies an integral equation. The latter is solved by the classical method of moments. The authors propose the use of globally defined, continuous basis functions for the expansion of the current dipole density.

The proposed global expansion provides an improvement of the numerical stability and the performance of the simulation, over classical approaches. The proposed method is tested against both measured and synthetic data obtained by a different defect model.

The new discretisation scheme – in contrast to the classical approaches – does not need the discretisation of the defect volume. This involves numerous advantages that are discussed in the paper.

Three methods are presented for the approximate prediction of losses in laminated transformer cores. The input data of the calculations are the field distribution obtained by a FEM code assuming the laminated core as a homogeneous medium that conductivity is zero in the direction perpendicular to the lamination. These data are processed by the developed methods to obtain an agreeable approximation of the power losses in the transformer plate. For each approach the same benchmark problem is solved to exploit the properties of the approaches. The goal of the presented study is to select the most suitable method that can be used as a postprocessor of a FEM code.

The purpose of this paper is to propose an efficient numerical simulation tool based on FEM, by which the EMC shielding effect characteristics of power cables can be predicted in the 30-1,000 MHz frequency range, as if it would be measured by the absorbing clamp method.

The simulation method is based on decomposition: a 2D axisymmetric RF FE model is used for describing the whole measurement set-up, while a 3D quasi-static FE model is used for the symmetry cell of the shielding layer in order to capture the effect of its fine geometric details.

Comparison with real measurements shows that the shielding characteristics can be reliably predicted this way, with some deviation in the low end of the frequency range though.

This simulation tool can be applied in the design and optimization of braided cable shields to be used in the automotive industry.

Two numerical models are coupled by the novel concept of “equivalent shielding layer”, which is obtained by homogenization.

The purpose of this paper is to accelerate the time‐consuming task of assembling the impedance matrix resulting from the discretization of integral equations by the moment method, accelerated using massively parallel processing scheme.

This paper provides several approaches for the implementation of moment method on compute unified device architecture (CUDA) capable general purpose video cards, as well as giving general implementation design patterns and a good overview on the topic.

The proposed method seems to be efficient in the light of the presented numerical results.

The subject of the paper is an evolving, considerably new aspect among computation techniques which could be of high interest for the scientific community.