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This paper aims to describe a new concept of transformer based on the displacement current. The paper shows how this idea can be translated into reality and presents an example of a working design.

The authors replace the primary winding of the transformer with a capacitor. The displacement current between the capacitor plates induces a magnetic flux in the core. This flux in turn induces electromotive force in the classical secondary winding.

The basic mathematical aspects illustrated by results obtained from a simulation developed using a commercial software ANSYS-HFSS are given. The saturation of the magnetic core due to the applied high-frequency range is investigated and simulated using a finite difference time domain code implemented in MATLAB. A prototype transformer was built and tested; the obtained results confirm the previous ones from simulations.

A new concept of the single winding transformer was used as a pulse forming circuit.

In the paper establishing the benchmark tests for open boundary problems as it has been done in other branches of electromagnetic field calculations is proposed. Consideration is given to what input and output data should be defined for the benchmark problems. In the appendix one proposal for benchmark problems is presented.

Arthritis, the illness of the bones, is one of the diseases which especially attack the knee joint. Magnetic stimulation is a very promising treatment, although not very clear as to its physical background. Deals with the mathematical simulation of the therapeutical technique, i.e. the magnetic stimulation method. Considers the low‐frequency magnetic field. To consider eddy currents one uses the pair of potentials: electric vector potential T→ and magnetic scalar potential Ω . Since the problem is of low frequency and the electric conductivity of biological tissues is very small, consideration of electric vector potential only is quite satisfactory.

Two new benchmark inverse problems for eddy currents are proposed. The first originates in the optimal design of the tubular inductive heater. The authors’ goal is to offer a simple problem which will check whether new software is able to minimize a multimodal objective function. The second benchmark is a simplified model of a hardening device. The purpose of this problem is to test the ability of the software to deal with different design parameters. This benchmark can be easily extended for more complicated, coupled fields problems. For both benchmarks reference standard solutions are presented. They were obtained using a finite element package for electromagnetics, developed by the authors.

The purpose of this paper is to describe a new concept of a computer system devoted to simulations of electromagnetic fields inside the human body. The main idea is based on application of the cloud computing approach to the electromagnetic simulator for inexperienced operators.

Modular design of the system is based on web technologies. The logic of simulation processes is stored in the form of scenarios consisting of several simple steps.

The authors found that a system based on a predefined, precise scenario will help an inexperienced user to solve realistic EMF simulations using state‐of‐the‐art technology. Highly modular application could be easily extended to the new functionality provided by independent programs (Processors) utilizing any type of a dedicated hardware platform.

The remote computing is known by computer science for its early beginning, but extraordinary growth of the internet network is renewing this term for the whole societies. Nowadays all kinds of applications are moving out of the desktop computers. The concept presented in this paper extends this new approach into realistic EMF simulation software.

The authors have designed a system which is extremely easy to use and thus accessible to everyone. It means that the user front‐end should have low computer hardware requirements and it could be operated by an untrained person. It is assumed that it will be fully usable, even by the first‐time, incidental user.

The presented project is one of the very few examples of utilization of the web‐technologies for numerical simulations. The unusual user interface based on the sequence of predefined steps makes the system appropriate for a wide audience.

The electric stimulation of the vagus nerve is used to obtain therapeutic results in epilepsy, depression and Alzheimer diseases. The purpose of this paper is to show numerical model of stimulation, focusing on the mathematical approach to modeling a phenomenon of neural cells activation and its propagation in the nerve.

The paper presents a model based on the bidomain theory. It uses two continuous, averaged domains which depict the intra‐ and extra‐cellular domains and are connected with the membrane ionic currents. The numerical model uses 3D cylindrical model approximating the anatomical shape of the neck. The simulator is based on a time domain finite element method.

The presented approach allows to model the discrete behaviour of the membrane potential in the macroscopic, realistic model of the nerve. The validation of the parameters with the velocity of activation propagations suggests the strong disscussion on physical interpretation to the bidomain theory parameters. To obtain realistic results the parameters needed to be unrealistic.

The paper presents the combination of bidomain model of neural tissue with the time domain finite element method along with the atributes of bidomain model for realistic modeling of the process of propagtion of activation.

The hybrid optimization tool presented in this paper combines generational genetic algorithms (GA) and variable metric (VM) optimizers. Both GA and VM may deal with the same, parameterized description of the inverse problem and a switch from GA to VM is being made automatically. GA is used to locate a subdomain in the design variables space containing the global minimum of the objective function. This global minimum may be found then, quickly and precisely, with the deterministic optimizer. The crucial concern of the hybrid algorithm design is to switch from stochastic to deterministic algorithm is such a way as to ensure that the global solution will be found in the fastest way. The article is focused on the algorithm which is able to determine whether GA has already found the desired subdomain described above. This algorithm is based on the cluster analysis using seed points and density‐determined hyperspheres.