Andrijana Kuhar

Ss. Cyril and Methodius University in Skopje · Faculty of Electrical Engineering and Information Techologies

The presented method determines the electric potential distribution in a modeled human muscle excited by a current pulse source placed on its surface. The electric potential in the muscle volume is calculated while considering the anisotropic and dispersive properties of its conductivity and permittivity. The developed numerical procedure is based...

Depolarization and repolarization of the myocard results in specific wave shapes that are recognizable in an ECG signal and are characterized by their length, rise time and amplitude. Changes in these characteristics usually indicate anomalies in the function of the heart. Automatic detection of characteristic segments of the ECG signal is of cruci...

Laplace’s differential equation is one of the most important equations which describe the continuity of a system in various fields of engineering. As a system gets more complex, the need for solving this equation numerically rises. In this paper we present an accuracy investigation of three of the most significant numerical methods used in computat...

Circuit models of horizontal and vertical grounding electrodes are traditionally used in high-frequency (HF) analysis, although underlying approximations limit their accuracy to some low frequency range. Recently, a number of new circuit models have been introduced, but the improvement of the accuracy at HF has not been systematically evaluated so...

Electromagnetic fields around transmission lines are of particular interest because of their large magnitude. Exposure to such fields may affect surrounding equipment or pose a safety risk. Time-varying fields give rise to current densities in the human body. In this paper a spheroidal model of the human body is used to calculate the intensity of t...

The intensity of ELF electric and magnetic fields near transmission lines is of particular interest in environmental and equipment protection studies. The use of numerical tools is the most efficient method for their assessment. In this paper, we numerically compute the electric and magnetic fields near different configurations of high-voltage tran...

Spoken language is what distinguishes humans from other species. It is the easiest, yet the most complex action we perform. Precise and coordinated movement of multiple articulators is required in order to generate spoken sounds or phonemes. The organization of phonemes into complex semantic structures is currently a system of communication that pe...

Диференцијални равенки кои немаат директно аналитичко решение се многу честа појава како во науката, така и во инженерството. Меѓу нив е и Лапласовата-диференцијална равенка од втор ред со која може да се опишат голем број електрични и физички појави во инженерството, а особено во неговата потесна област биомедицината. Користејќи ги придобивките од...

Rigorous electromagnetic models and approximations are traditionally based on the Sommerfeld's resolution for Hertz vector potentials. However, another resolution, based on transverse Hertz vector potentials, also exists. This paper shows that a low frequency approximation, based on this resolution, for wires embedded in a two-layered earth, is mor...

Depolarization and repolarization of the myocard results in specific wave shapes that are recognizable in an ECG signal and are characterized by their length, rise time and amplitude. Changes in these characteristics usually indicate anomalies in the function of the heart. Automatic detection of characteristic segments of the ECG signal is of cruci...

Efficient approach for full-wave modelling of grounding systems is provided. First the electric field integral equations are cast in form that is more suitable for grounding analysis and have improved convergence. Then numerical evaluation of the Sommerfeld integrals is substituted by bivariate cubic interpolation procedure of the solutions from pr...

The main difference between the application of the method of moments (MoM) to grounding system and antenna analysis is the shunt energization by the injection of current. There is no consensus on the modeling of such energization, which is also crucial for the definition of quantities that characterize grounding system time and frequency behavior....

In this paper the dynamic behavior of grounding electrodes is investigated by calculating their impedance to ground. The calculations are performed by implementing popular modelling approaches including circuit, transmission line, and electromagnetic field (EMF) model. The attention of this paper is given to the circuit based (CBM) method. The resu...

This paper presents a methodological analysis of differences between the classical method of moments (MoM) approach and the partial element equivalent circuit (PEEC) approach to determination of current along a conductor. A step by step investigation is performed of the two approaches while they are applied on a perfect conductor placed in a conduc...

This paper presents transient analysis of a horizontal buried conductor performed by applying the Partial Element Equivalent Circuit (PEEC) method. A fast rising pulse is injected by a current source at one end of a perfect conductor placed in a finitely conductive ground. The presence of ground/air boundary surface is taken into account by impleme...

A method for calculation of the current density distribution in human muscle tissue excited by a current pulse source placed on its surface. The theoretical analysis of the problem is based on representation of the electrode placed on the skin with a series of images, thus taking in account the influence of different material properties. The calcul...

The presented method determines the electric potential distribution in a modeled human muscle excited by a current pulse source placed on its surface. The electric potential in the muscle volume is calculated while considering the anisotropic and dispersive properties of its conductivity and permittivity. The developed numerical procedure is based...