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The aim of this article is to draw attention to the importance of open discussion for the proper development of science.

In the phase of the developed market economy we are currently in, the evaluation of each human activity, including scientific work, which is based on an evaluation of the value of the profit it brings. Unfortunately, it does not always work correctly.

The problem will be analyzed using as an example the erroneous (according to the author) use of fractional derivatives in electrical engineering.

To the best of the author’s knowledge, this is the author's original point of view on the problem of improper use of fractional derivatives in electrical engineering.

The presented research proposes a method aimed to improve a case retrieval phase of the case-based reasoning (CBR) system through optimization of feature relevance parameters, i.e. feature weights.

The improvement is achieved by applying the metaheuristic optimization technique, called electromagnetism-like algorithm (EM), in order to appropriately adjust the feature weights used in k-NN classifier. The usability of the proposed EM k-NN algorithm is much broader since it can also be used outside the CBR system, e.g. for solving general pattern recognition tasks.

It is showed that the proposed EM k-NN algorithm improves the baseline k-NN model and outperforms the appropriately tuned artificial neural network (ANN) in the task of predicting the case (data record) output values. The results are verified by performing statistical analysis.

The proposed method is currently adjusted to deal with numerical features, so, as a direction for future work, the variant of EM k-NN algorithm that deals with symbolic or some more complex types of features should be considered.

EM k-NN algorithm can be incorporated as a case retrieval component inside a general CBR system. This is the future direction of the investigation since the authors intend to build a complete specialized CBR system for construction project management. The overall CBR with incorporated EM k-NN will have significant implication in the construction management as it will be able to produce more accurate prediction of viability and the life cycle of new construction projects.

The electromagnetism-like algorithm is applied to the problem of finding feature weights for the first time. EM potential for solving the problem of weighting features lies in its internal structure because it is based on the real-valued EM vectors. The overall EM k-NN algorithm is applied on data sets generated from real construction projects data corpus. The proposed algorithm proved its efficiency as it outperformed baseline k-NN model and ANN. Its applicability in more complex and specialized CBR systems is high since it can be easily added due to its modular (black-box) design.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

There are two conflicting views about electromagnetic phenomena. The first is based on the action between stationary and moving particles of electric charge and the second on energy distributions in electric and magnetic fields. The difference between these approaches is seen most clearly in the roles assigned to the potentials. According to the particle view the potentials convey the force from one particle to another, whereas in the field approach the potentials are system parameters related to the field energy. The article compares the two views and concludes that the particle view faces impossible difficulties because it ascribes local significance to quantities which are unobservable and conflicts with the quantum‐mechanical understanding of charge as a statistical distribution.

The paper presents a historical review, the state of the art and recent advances in the field of computational electromagnetics at leading universities and research institutes in Poland. Contributions made by Polish scientists to the development of fundamental electromagnetism, as well as to computational methods, are emphasized, and some conclusions are drawn regarding expected future developments.

Introduction Depending on the way of teaching process organization the theory of electromagnetic field is considered either as a part of theoretical electrical engineering or as an individual subject. The electromagnetic field theory plays a double role in the education of electric engineers: comprehensive or specialized one. However, the electromagnetic field can be treated from the other point of view. It can be lectured with pointing out the calculation methods or phenomena occurring in “pure” electromagnetic field, and on the other hand, with reference to phenomena occurring in coupled fields, where those fields are affecting non‐living or having objects.

Rectangular conductors play an important role in planar transmission line structures, multiconductor transmission lines, in power transmission and distribution systems, LCL filters, transformers, industrial busbars, MEMs devices, among many others. The precise determination of the inductance of such conductors is necessary for their design and optimization, but no explicit solution for the AC resistance and internal inductances per-unit length of a linear conductor with a rectangular cross-section has been found, so numerical methods must be used. The purpose of this paper is to introduce the use of a novel numerical technique, the proper generalized decomposition (PGD), for the calculation of DC and AC internal inductances of rectangular conductors.

The PGD approach is used to obtain numerically the internal inductance of a conductor with circular cross-section and with rectangular cross-section, both under DC and AC conditions, using a separated representation of the magnetic vector potential in a 2D domain. The results are compared with the analytical and approximate expressions available in the technical literature, with an excellent concordance.

The PGD uses simple one-dimensional meshes, one per dimension, so the use of computational resources is very low, and the simulation speed is very high. Besides, the application of the PGD to conductors with rectangular cross-section is particularly advantageous, because rectangular shapes can be represented with a very few number of independent terms, which makes the code very simple and compact. Finally, a key advantage of the PGD is that some parameters of the numerical model can be considered as additional dimensions. In this paper, the frequency has been considered as an additional dimension, and the internal inductance of a rectangular conductor has been computed for the whole range of frequencies desired using a single numerical simulation.

The proposed approach may be applied to the optimization of electrical conductors used in power systems, to solve EMC problems, to the evaluation of partial inductances of wires, etc. Nevertheless, it cannot be applied, as presented in this work, to 3D complex shapes, as, for example, an arrangement of layers of helically stranded wires.

The PGD is a promising new numerical procedure that has been applied successfully in different fields. In this paper, this novel technique is applied to find the DC and AC internal inductance of a conductor with rectangular cross-section, using very dense and large one-dimensional meshes. The proposed method requires very limited memory resources, is very fast, can be programmed using a very simple code, and gives the value of the AC inductance for a complete range of frequencies in a single simulation. The proposed approach can be extended to arbitrary conductor shapes and complex multiconductor lines to further exploit the advantages of the PGD.

The purpose of this study is to develop an electromagnetic loading method for online measurement of the acoustoelastic coefficients and bus bar plane stress.

A method based on the combination of electromagnetic loading and the acoustoelastic effect is proposed to realize online measurement of acoustoelastic coefficients and plane stress. Electromagnetic loading is performed on the bus bar specimen, and the acoustoelastic coefficients and the bus bar plane stress are obtained by the ultrasonic method. An electromagnetic loading experimental platform is designed to provide electromagnetic force to the metal plate, including an electromagnetic loading module, an ultrasonic testing module and a stress simulation module.

The feasibility of the proposed electromagnetic loading method is proved by verification experiments. The acoustoelastic coefficients and plane stress measured using the electromagnetic loading method are more accurate than those measured using the traditional method.

The proposed electromagnetic loading method provides a new study perspective and enables more accurate measurement of the acoustoelastic coefficients and plane stress. The study provides an important basis for evaluating the operation status of electrical equipment.

This paper aims to study the possibility of controlling the electromagnetic stirrer (EMS) is fundamental in a continuous casting line to achieve the desired properties of homogeneity and mechanical strength in the solidified cast.

Coupled electromagnetic (EM) and fluid dynamic (FD) simulations allow to predict the mixing effect on molten metal, in terms of velocity amplitude and shape of the flow. This paper describes the numerical results of EMS effect within a cylindrical crucible, surrounded by a solenoidal inductor, filled with a low melting temperature alloy, i.e. GalInStan.

Induced forces and resulting velocity distribution of the flow of the liquid metal have been calculated depending on varying amplitude and frequency of the supplied current. As expected, at a given amplitude of the current supply, the velocity distribution shows a maximum at a certain frequency while the intensity of electrodynamic forces monotonically increase as the frequency increases

The paper deals with simply models and experiments applied to coupled EM and FD problem, to assess the applied methodology.

This study aims to improve the bat algorithm (BA) performance for solving optimization problems in electrical engineering.

For this task, two strategies were investigated. The first one is based on including the crossover technique into classical BA, in the same manner as in the genetic algorithm method. Therefore, the newly generated version of BA is called the crossover–bat algorithm (C-BA). In the second strategy, a hybridization of the BA with the Nelder–Mead (NM) simplex method was performed; it gives the NM-BA algorithm.

First, the proposed strategies were applied to solve a set of two standard benchmark problems; then, they were applied to solve the TEAM workshop problem 25, where an electromagnetic field was computed by use of the 2D non-linear finite element method. Both optimization algorithms and finite element computation tool were implemented under MATLAB.

The two proposed optimization strategies, C-BA and NM-BA, have allowed good improvements of classical BA, generally known for its poor solution quality and slow convergence rate.