Irena Kováčová

Prof. Dr. Irena Kováčová

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 February 2022 in Sensors
Verified
Journal Article
Open access
PDF file
PJPatrik Jacko
Patrik Jacko
MBMatej Bereš
Matej Bereš
IKIrena Kováčová
Irena Kováčová
JMJan Molnar
Jan Molnar
Tibor VinceTibor Vince
Tibor Vince
Dobroslav KovacDobroslav Kovac
Dobroslav Kovac
The article describes the implementation of IoT technology in the teaching of microprocessor technology. The method presented in the article combines the reality and virtualization of the microprocessor technology laboratory. A created IoT monitoring device monitors the students’ microcontroller pins and sends the data to the server to which the teacher is connected via the control application. The teacher has the opportunity to monitor the development of tasks and student code of the program, where the functionality of these tasks can be verified. Thanks to the IoT remote laboratory implementation, students’ tasks during the lesson were improved. As many as 53% (n = 8) of those students who could improve their results achieved an improvement of one or up to two tasks during class. Before the IoT remote laboratory application, up to 30% (n = 6) of students could not solve any task and only 25% (n = 5) solved two tasks (full number of tasks) during the class. Before implementation, 45% (n = 9) solved one problem. After applying the IoT remote laboratory, these numbers increased significantly and up to 50% (n = 10) of students solved the full number of tasks. In contrast, only 10% (n = 2) of students did not solve any task.

28 November 2020 in JUCS - Journal of Universal Computer Science
Verified
Journal Article
Open access
PDF file
Tibor VinceTibor Vince
Tibor Vince
MBMatej Bereš
Matej Bereš
IKIrena Kováčová
Irena Kováčová
JMJan Molnar
Jan Molnar
BFBranislav Fecko
Branislav Fecko
Milan GuzanMilan Guzan
Milan Guzan
The paper presents analyses of the implementation of IoT in the patent technology of the remote measuring laboratory (VMLab). The technology allows to create a new electrical connection between different devices, where the connection diagram was not defined before. This may be done remotely around the world. To begin with, an application of this technology as a remote measuring laboratory is presented and described. Analyses of the possible application of IoT technology in the Remote Measurement Laboratory (VMLAB) with a final design are also presented. The research focuses on an efficient way to retrieve measured values synchronized over the Internet from multiple measuring devices and controllable devices, without an Ethernet or Wi-Fi interface from the manufacturer. The analyses may also be useful when implementing an additional IoT approach to existing systems.

8 July 2021 in Energies
Verified
Journal Article
Open access
PDF file
MBMatej Bereš
Matej Bereš
Dobroslav KovacDobroslav Kovac
Dobroslav Kovac
Tibor VinceTibor Vince
Tibor Vince
IKIrena Kováčová
Irena Kováčová
JMJan Molnar
Jan Molnar
ŠGŠimon Gans
Šimon Gans
The article describes the principles based on which it is possible to obtain energy from renewable sources more efficiently. The principles use the conventional DC-DC interleaved buck converter based on the common electronic component types and the control strategy. A novelty of such a proposed solution lies in the methods which are not new, but with the right combination, better results can be achieved. The resulting method can be implemented into various topologies where the highest efficiency for wide input power is required. In case of the renewable energy sources where the power can vary hugely during the day, the proposed method can be implemented. Therefore, the article provides several steps, from calculation through simulation to experimental results that brings reader close to understanding of a such proposed solution.

3 November 2022 in Energies
Verified
Journal Article
Open access
PDF file
Dobroslav KovacDobroslav Kovac
Dobroslav Kovac
Tibor VinceTibor Vince
Tibor Vince
MBMatej Bereš
Matej Bereš
JMJan Molnar
Jan Molnar
JDJozef Dziak
Jozef Dziak
IKIrena Kováčová
Irena Kováčová
The article describes the design of a universal simulation model of a voltage regulator for applications compatible with the globally used PSpice program. Users can create a model of any type of integrated switching voltage regulator that is currently available on the market by setting its individual parameters. The proposed connection of the regulator was applied in the connection of the buck DC–DC converter. The accuracy of the model was verified by comparing the results obtained by the simulation to other official models and to practical measurements taken on a real sample of the converter. The versatility of the model was proven by comparison with another type of converter with different parameters.

17 November 2023 in Sustainability
Verified
Journal Article
Open access
PDF file
MPMarek Pavlik
Marek Pavlik
MBMatej Bereš
Matej Bereš
Dobroslav KovacDobroslav Kovac
Dobroslav Kovac
Tibor VinceTibor Vince
Tibor Vince
IKIrena Kováčová
Irena Kováčová
JMJan Molnar
Jan Molnar
As the global emphasis on solar energy intensifies, optimizing the efficiency of photovoltaic panels becomes crucial in meeting energy demands sustainably. Addressing this, our research delves deeply into advancing maximum power point tracking (MPPT), a pivotal component in perfecting the energy conversion process. Leveraging state-of-the-art mathematical modeling, in-depth simulations, and comprehensive experimental validation, we set out to markedly refine the performance of non-isolated multi-branch buck DC–DC converters. In this pursuit, we introduce an innovative algorithm meticulously designed to adjust the number of active branches. This adjustment is rooted in robust efficiency metrics, ensuring optimal power delivery even under dynamic and fluctuating conditions. We place a distinct emphasis on the transformative role of current in determining converter efficiency. Drawing from our findings, we advocate for an adaptive control strategy, precisely engineered to thrive in a spectrum of operational contexts. With this study, we not only present pivotal contributions to the domain of photovoltaic technology but also chart out clear expectations for future endeavors. Our hope is that these advancements serve as foundational steps, guiding the evolution of sustainable energy generation.

11 October 2023 in Sensors
Verified
Journal Article
Open access
PDF file
ŠGŠimon Gans
Šimon Gans
JMJan Molnar
Jan Molnar
Dobroslav KovacDobroslav Kovac
Dobroslav Kovac
IKIrena Kováčová
Irena Kováčová
BFBranislav Fecko
Branislav Fecko
Tibor VinceTibor Vince
Tibor Vince
The paper deals with a brief overview of magnetoelastic sensors and magnetoelastic sensors used in general for sensing bending forces, either directly or sensing bent structures, and defines the current state of the art. Bulk magnetoelastic force sensors are usually manufactured from transformer sheets or amorphous alloys. In praxis, usually, a compressive force is sensed by bulk magnetoelastic sensors; however, in this paper, the sensor is used for the measurement of bending forces, one reason being that the effect of such forces is easily experimentally tested, whereas compressive forces acting on a single sheet make buckling prevention a challenge. The measurement of the material characteristics that served as inputs into a FEM simulation model of the sensor is presented and described. The used material was considered to be mechanically and magnetically isotropic and magnetically nonlinear, even though the real sheet showed anisotropic behavior to some degree. A sinusoidal magnetizing current waveform was used in the experimental part of this paper, which was created by a current source. The effects of various frequencies, amplitudes, and sensor geometries were tested. The experimental part of this paper studies the sensors’ RMS voltage changes to different loadings that bend the sheet out of its plane. The output voltage was the induced voltage in the secondary coil and was further analyzed to compute the linearity and sensitivity of the sensor at the specific current characteristic. It was found that for the given material, the most favorable operating conditions are obtained with higher frequency signals and higher excitation current amplitudes. The linearity of the sensor can be improved by placing the holes of the windings at different angles than 90° and by placing them further apart along the sheet’s length. The current source was created by a simple op-amp voltage-to-current source controlled by a signal generator, which created a stable waveform. It was found that transformer sheet bending sensors with the dimensions described in this paper are suitable for the measurement of small forces in the range of up to 2 N for the shorter sensors and approximately 0.2 N for the longer sensors.