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The purpose of this paper is to investigate how the new theory on the general systemic yoyos can be plausibly employed to provide novel explanations for some of the well‐known laboratory experiments of physics and how a different theory that is more refined than the currently accepted theories can be established for illustrating phenomena that have not been completely explainable by using the traditional theories.

The general field structures of systemic yoyos, combined with some of the well‐known laboratory observation of physics, are employed as the basic methodology for the current paper.

Owing to the co‐existence of magnetic fields and ring‐shaped negative electric fields, all possible ways for an electromagneton to be fired into a stable, uniform‐intensity magnetic field are investigated. How such an electromagneton could be traveling under the mutual influence of the fields is described with details.

The value of this paper lies on the fact that it points out a brand new and practically applicable theory for looking at some of the well‐recorded phenomena of electromagnetism.

The paper aims to highlight the efficiency of double complex numbers for the complete analysis of the intensity of the electric field produced by power lines.

One set of complex numbers is used to represent all the plane vectors (vector distances) and another set of complex numbers is used to represent all the sinusoidal time varying quantities (electric charges and voltages). The simultaneous representation of vector distances and sinusoidal time varying quantities with complex numbers gives elegant expressions to the electric field vector and simplifies the mathematical relations to a great degree.

General analytical formulas are developed for the direct calculation of all the parameters of the elliptically rotating electric field (rms value, major and minor semi‐axis of the ellipse, angles of the semi‐axes, tracing direction, polarization). The analytical formulas depend on the components of the double complex number.

The proposed method can be applied only on 2D problems, especially power lines where the electric field vector can be expressed as a double complex number.

Double complex numbers are proved in this paper as a very effective mathematical tool for the complete analysis of the electric field produced by power lines. The expression of the electric field vector as a double complex number allows the direct calculation of all the parameters of the electric field with analytical relations.

The purpose of this paper is to reach two goals: one is to generalize the well‐studied theories of electricity and magnetism to the enrichment of deepened understanding of the general systemic yoyo model, and the other is to employ the established yoyo model to provide more refined explanations for some of the known experimental observations in physics.

The general structure and the field characteristics of the general systemic yoyo model are employed as the basis of our exploration in this paper. Then, methods of quantitative analysis are introduced to address some of the problems encountered.

Among several new results, many important concepts, such as ring‐shaped electric fields, cylinders of equal potential intensities, yoyo resistances, yoyo capacitors, etc. are introduced and studied in some detail. Several important Laws in electromagnetic theory, such as Ohm's law, Kirchhoff's laws, etc. are generalized to the case of the general systemic yoyo model. The refined theory is applied to provide theoretical explanations for some laboratory‐observed phenomena that cannot be well illustrated by either Faraday's theory of electromagnetic induction or Lenz's law.

Phenomena related to electricity and magnetism are explained the first time in history by using a unified model: the systemic yoyo model. At the same time, some well established Laws in physics are generalized to scenarios of this general mode with the hope that these new Laws can be applied equally well to natural and social sciences in the coming years.

This paper aims to focus on the finite element method in the frequency domain (FD-FEM) for the transient electric field in the non-sinusoidal steady state under the non-sinusoidal periodic voltage excitation.

Firstly, the boundary value problem of the transient electric field in the frequency domain is described, and the finite element equation of the FD-FEM is derived by Galerkin’s method. Secondly, the constrained electric field equation on the boundary in the frequency domain (FD-CEFEB) is also derived, which can solve the electric field intensity on the boundary and the dielectric interface with high accuracy. Thirdly, the calculation procedures of the FD-FEM with FD-CEFEB are introduced in detail. Finally, a numerical example of the press-packed insulated gate bipolar transistor under the working condition of the repetitive turn-on and turn-off is given.

The FD-CEFEB improves numerical accuracy of electric field intensity on the boundary and interfacial charge density, which can be achieved by modifying the existing FD-FEMs’ code in appropriate steps. Moreover, the proposed FD-FEM and the FD-CEFEB will only increase calculation costs by a little compared with the traditional FD-FEMs.

The FD-CEFEB can directly solve the electric field intensity on the boundary and the dielectric interface with high accuracy. This paper provides a new FD-FEM for the transient electric field in the non-sinusoidal steady state with high accuracy, which is suitable for combined insulation structure with a long time constant.

The purpose of this paper is to estimate the influence of long‐term, whole‐body exposure of rats to strong, static electric field with physical parameters generated nearby high voltage direct current (HVDC) transmission lines on the intensity of reactive oxygen species generation analyzed indirectly, basing on the measurement of malone dialdehyde level, as well as on the activity of enzymatic antioxidant defence system.

In rats exposed to static electric field with intensity of 16, 25 and 35 kV/m, respectively, or sham‐exposed eight hours daily for 56 days, in the obtained plasma, erythrocytes lysates and liver homogenates the activity of some antioxidant enzymes as well as the concentration of malone dialdehyde were determined with use of spectrophotometric and kinetic methods.

It was observed that long‐term exposure of rats to static electric field causes only temporary compensatory changes in the concentration of malone dialdehyde and transient changes in the activity of enzymatic antioxidant system, both in blood and in liver tissue in the form of temporary inhibition of activity of most antioxidant enzymes during exposure cycle, with subsequent compensatory increase in this activity after the end of exposure cycle, enabling maintenance of prooxidant‐antioxidant balance in the organism of experimental animals and inhibition of peroxidation process.

Presented data indicate that construction of air HVDC transmission lines, according to actual compulsory regulations, enables serious health hazards related to persistent disturbances of prooxidant‐antioxidant balance to be avoided.

In the experiment it was confirmed, for the first time, that long‐term exposure to strong static electric field causes transient compensatory changes of prooxidant‐antioxidant balance in living organisms.

To determine the electrical field E₁(t) in spherical and cylindrical gas voids existing in an insulator by considering surface conductivity of gas voids having an electrical permittivity of ε₁ and conductivity of γ₁ for DC and AC situations.

Analytical expressions satisfying Laplace equation for inside and outside of the cylindrical and spherical gas voids in an insulator located in an external electrical field having a definite time dependent character, have been derived by considering the surface conductivity of the gas void. The coefficients included by these analytical expressions have been determined by utilizing the continuity equation of the current on the surface of the voids.

It has been demonstrated that the electrical field remains uniform in spherical and cylindrical gas voids when the surface conductivity of gas void has been considered. It has been determined that the contact charging process of different shaped particles has an exponential characteristic, and some expressions have been derived to determine the time constants of this process for practical purposes.

The results have been applied to the problems about contact charging of semi‐spherical and semi‐cylindrical insulated particles located at a charged surface and problems about the calculation of onset discharging voltage of ionization process in dielectric including gas voids.

For spherical and cylindrical gas voids, the onset discharging voltage corresponding to the ionization process occurring in gas voids has increased by increasing the surface conductivity of the void. For the limit value of the surface conductivity, the voids in the insulator behaves like metal particles distributed into the insulator, for this reason, at the outside of the void, especially in the regions where the voids are close to the electrodes and each other, the electrical field will be non‐uniform and will increase. This situation will cause the ignition of the partial discharge and destroy to the insulator.

The purpose of this paper is numerical calculation of total electric field in oil-paper insulation. Now, there is no effective method to consider the influence of space charges when calculating the total electric field distribution in the main insulation system of the valve-side winding of an ultra-high-voltage direct current converter transformer.

To calculate the total electric field in an oil-paper insulation system, a new simulation method in single-layer oil-paper insulation based on the transient upstream finite element method (TUFEM) is proposed, in which the time variable is considered. The TUFEM is used to calculate the total electric field in an oil-paper insulation system by considering the move law of space charges. The simulation method is verified by comparing the simulation results to the test data. The move law of space charges and distribution characteristics of the electric field under difference voltage values in single-layer oil-paper insulation were presented.

The results show that the TUFEM has an excellent accuracy compared with the test data. When carrier mobility is a constant, the time to reach the steady state is inversely correlated with the initial electric field intensity, and the distortion rate of the internal total electric field is positively correlated with the initial electric field intensity.

This paper provides an exploratory research on the simulation of space charge transport phenomenon in oil-paper and has guiding significance to the design of oil-paper insulation.

The purpose of this paper is to develop a numerical simulation method based on the transient upstream finite element method (FEM) and Schottky emission theory to reveal the distribution characteristics of space charge in oil-paper insulation.

The main insulation medium of the converter transformer in high voltage direct current transmission is oil-paper insulation. However, the influence of space charge is difficult to be fully considered in the insulation design and simulation of converter transformers. To reveal the influence characteristics of the space charge, this paper proposes a numerical simulation method based on Schottky emission theory and the transient upstream FEM. This method considers the influence of factors, such as carrier mobility, carrier recombination coefficient, trap capture coefficient and diffusion coefficient on the basis of multi-physics field coupling calculation of the electric field and fluid field.

A numerical simulation method considering multiple charge states is proposed for the space charge problem in oil-paper insulation. Meanwhile, a space charge measurement platform based on the electrostatic capacitance probe method for oil-paper insulation structure is built, and the effectiveness and accuracy of the numerical simulation method is verified.

A variety of models are calculated and analyzed by the numerical simulation method in this paper, and the distribution characteristics of the space charge and total electric field in oil-paper insulation medium with single-layer, polarity reversal of plate voltage and double-layer are obtained. The research results of this paper have the guiding significance for the engineering application of oil-paper insulation and the optimal design of converter transformer insulation.

In electrochemotherapy, flexible electrodes, composed by an array of needles, are applied to human tissues to treat large surface tumors. The positioning of the needles in the tissue depends on the surface curvature. The parallel needle case is preferred, as their relative inclinations strongly affect the actual distribution of electric field. Nevertheless, in some case, small inclinations are unavoidable. The purpose of this paper is to study the electric field distribution for non-parallel needles.

The effect of electrode position is evaluated systematically by means of numerical models and experiments on phantoms for two different angles (5° and 30°) and compared with the case of parallel needles. Potato model was used as phantom, as this tissue becomes dark after few hours from electroporation. The electroporation degree was gauged from the color changings on the potatoes.

The distribution of electric field in different needle configuration is found by means of finite element analysis (FEA) and experiments on potatoes. The electric field level of inclined needles was compared with parallel needle case. In particular, the electric field distribution in the case of inclined needles could be very different with respect to the one in the case of parallel needles. The degree of enhancement for different inclinations is visualized by potato color intensity. The FEA suggested that the needle parallelism has to be maintained as possible as if the tips are closer to each other, the electric field intensity could be different with respect to the one in the case of parallel needles.

This paper analyzes the effect of inclined electrodes considering also the non-linearity of tissues.

The purpose of this paper is to establish the relevant quantitative methods for the investigation of the eddy and meridian fields of the general systemic yoyo model.

On the basis of established systemic yoyo models for electrons and positrons, flows of negative yoyo charges are naturally identified with electric currents so that use of the well‐developed quantitative methods can be made in electromagnetic theory to investigate the relationship between eddy and meridian fields of the general systemic yoyo model.

A general method is established on how to compute the intensity of the magnetic yoyo fields accompanying a moving yoyo charge or a canal of yoyo flow. A quantitative representation for magnetic yoyo fields is provided. And, the well‐known Ampere's law of electricity is generalized to the case of general yoyo flows.

By establishing an adequate quantitative method for the general systemic yoyo model, it should be possible to know more about the yoyo model and gain additional potential to successfully employ this model in various areas of learning, as proposed by Lin.