TY - JOUR AU - Šiljegović, M. AU - Cvejić, Ž. AU - Jankov, S. AU - Toth, E. AU - Herceg, D. AU - Odry, Péter AU - Tadity, Vladimir TI - Impedance and Dielectric Analysis of Nickel Ferrites: Revealing the Role of the Constant Phase Element and Yttrium Doping JF - ELECTRONICS (SWITZ) VL - 13 PY - 2024 IS - 8 PG - 14 SN - 2079-9292 DO - 10.3390/electronics13081496 UR - https://m2.mtmt.hu/api/publication/34836703 ID - 34836703 LA - English DB - MTMT ER - TY - JOUR AU - Herceg, Dejana AU - Rajs, Vladimir AU - Despotović, Živadin AU - Popadić, Bane AU - Šiljegović, Mirjana AU - Király, Zoltán AU - Vizvári, Zoltán Ákos AU - Wizner, Krisztián AU - Felde, Imre AU - Odry, Péter AU - Tadity, Vladimir TI - Double-Layer Coils Design for 11 kW Wireless Power Transfer JF - ELECTRONICS (SWITZ) VL - 13 PY - 2024 IS - 3 PG - 20 SN - 2079-9292 DO - 10.3390/electronics13030547 UR - https://m2.mtmt.hu/api/publication/34547851 ID - 34547851 N1 - Faculty of Technical Sciences, Department of Power, Electronic and Telecommunication Engineering, University of Novi Sad, Trg Dositeja Obradovića 6, Novi Sad, 21000, Serbia Faculty of Sciences, Department of Physics, University of Novi Sad, Trg Dositeja Obradovića 4, Novi Sad, 21000, Serbia Institute of Information Technology, University of Dunaujvaros, Tancsics M. Str. 1/A, Dunaujvaros, H-2401, Hungary John von Neumann Faculty of Informatics, Óbuda University, Becsi Str. 96/B, Budapest, H-1034, Hungary Symbolic Methods in Material Analysis and Tomography Research Group, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 6, Pecs, H-7624, Hungary Department of Environmental Engineering, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 2, Pecs, H-7624, Hungary Cellular Bioimpedance Research Group, Szentagothai Research Centre, University of Pecs, Ifjusag Str. 20, Pecs, H-7624, Hungary Institute of Engineering Sciences, University of Dunaujvaros, Tancsics M. Str. 1/A, Dunaujvaros, H-2401, Hungary Export Date: 16 February 2024 Correspondence Address: Tadic, V.; Institute of Information Technology, Tancsics M. Str. 1/A, Hungary; email: laslo.tadic@gmail.com Funding details: GINOP_PLUSZ-2.1.1-21-2022-00249 Funding details: Óbudai Egyetem Funding text 1: This research was funded by projects 2020-1.1.2-PIACI-KFI-2020-00166 and 2020-1.1.2-PIACI-KFI-2020-00173 of the University of Dunaujvaros and by project GINOP_PLUSZ-2.1.1-21-2022-00249 of the Óbuda University, co-financed by the Hungarian State. AB - The design of a wireless power transfer system with double rectangular coils for 11 kW power transfer is considered. System modeling and numerical calculation of the system parameters are described. Coils are made from available Litz wire, which has a smaller than necessary diameter for the required power. Thus, a setup with double layer coils was developed, which resulted in a modified design. Starting from a system consisting of coupled coils, as suggested by the standard for wireless power transfer Level 3 in class Z1, different coil and ferrite shield layouts were tested in numerical simulations, and their parameters were calculated. The prototype was constructed based on the simulated model with the best results and properties. Numerical results were verified by laboratory measurements, and a successful power transfer at 11 kW was achieved. LA - English DB - MTMT ER - TY - JOUR AU - Rajs, Vladimir AU - Herceg, Dejana AU - Despotović, Živadin AU - Bogdanović, Miroslav AU - Šiljegović, Mirjana AU - Popadić, Bane AU - Kiraly, Zoltan AU - Vizvári, Zoltán Ákos AU - Sári, Zoltán AU - Klincsik, Mihály AU - Felde, Imre AU - Odry, Péter AU - Tadity, Vladimir TI - Dead-Time Effect in Inverters on Wireless Power Transfer JF - ELECTRONICS (SWITZ) VL - 13 PY - 2024 IS - 2 PG - 14 SN - 2079-9292 DO - 10.3390/electronics13020304 UR - https://m2.mtmt.hu/api/publication/34496311 ID - 34496311 N1 - Faculty of Technical Sciences, Department of Power, Electronic and Telecommunication Engineering, University of Novi Sad, Trg Dositeja Obradovića 6, Novi Sad, 21000, Serbia Faculty of Sciences, Department of Physics, University of Novi Sad, Trg Dositeja Obradovića 6, Novi Sad, 21000, Serbia Institute of Information Technology, University of Dunaujvaros, Tancsics M. Str. 1/A, Dunaujvaros, H-2401, Hungary John von Neumann Faculty of Informatics, University of Obuda, Becsi Str. 96/B, Budapest, H-1034, Hungary Symbolic Methods in Material Analysis and Tomography Research Group, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 6, Pecs, H-7624, Hungary Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 2, Pecs, H-7624, Hungary Cellular Bioimpedance Research Group, Szentagothai Research Centre, University of Pecs, Ifjusag Str. 20, Pecs, H-7624, Hungary Export Date: 9 February 2024 Correspondence Address: Tadic, V.; Institute of Information Technology, Tancsics M. Str. 1/A, Hungary; email: tadity.laszlo@uni-obuda.hu Funding details: GINOP_PLUSZ-2.1.1-21-2022-00249 Funding text 1: This research was funded by projects 2020-1.1.2-PIACI-KFI-2020-00166 and 2020-1.1.2-PIACI-KFI-2020-00173 of the University of Dunaujavaros and by project GINOP_PLUSZ-2.1.1-21-2022-00249 of the University of Obuda, co-financed by the Hungarian State. AB - This paper presents a comprehensive analysis of the dead-time effects in wireless power transfer systems based on LCC-S topology. In these systems operating at high frequencies, the ratio of dead-time versus the operating period becomes critical, and the dead-time issue can cause certain problems regarding power quality, efficiency, and output voltage ripple. The impact of input quantities such as voltage and switching frequency on the efficiency and output power of the LCC-S-tuned WPT system was also investigated. The optimal combination of these parameters used to achieve the maximum efficiency for a target output power and to set the appropriate value of the dead time were determined by running multiple simulations using the MATLAB R2023b software platform. It was also shown that the output voltage remained unchanged with and without a load and up to 1200 ns of dead-time, which provides a simple implementation of the corresponding mathematical model. In the recommended interval of 600–1500 ns, the influence of the dead-time on the value of the output voltage amplitude is less than 10%. The validity of the proposed method was confirmed through the implementation of the experimental prototype, a 5 kW wireless power transmission system, and the obtained results were in accordance with the simulation results. LA - English DB - MTMT ER - TY - JOUR AU - Vizvári, Zoltán Ákos AU - Klincsik, Mihály AU - Odry, Péter AU - Tadity, Vladimir AU - Győrfi, Nina Rubina AU - Tóth, Attila AU - Sári, Zoltán TI - Continuous Electrode Models and Application of Exact Schemes in Modeling of Electrical Impedance Measurements JF - ELECTRONICS (SWITZ) VL - 13 PY - 2024 IS - 1 PG - 17 SN - 2079-9292 DO - 10.3390/electronics13010066 UR - https://m2.mtmt.hu/api/publication/34448557 ID - 34448557 N1 - Export Date: 22 January 2024 Correspondence Address: Vizvari, Z.; Department of Environmental Engineering, Boszorkany Str. 2, Hungary; email: vizvari.zoltan@mik.pte.hu AB - The crucial issue in electrical impedance (EI) measurements lies in the galvanic interaction between the electrodes and the investigated material. This paper brings together the basic and applied research experience and combines their results with excellent properties. Consequently, innovative precise methodologies have emerged, enabling the direct modeling of EI measurements, free from the inaccuracies often associated with numerical approaches. As an outcome of the efficiency and robustness of the applied method, the conductivity of the material and the electrodes are represented by a common piecewise function, which is used to solve the differential equation modeling of the EI measurement. Moreover, this allows the possibility for modeling the conductivity of electrodes with continuous functions, providing an important generalization of the Complete Electrode Model (CEM), which has been widely used so far. The effectiveness of the novel approach was showcased through two distinct case studies. In the first case study, potential functions within both the material and the electrodes were computed using the CEM. In the second case study, calculations were performed utilizing the newly introduced continuous electrode model. The simulation results suggest that the new method is a powerful tool for biological research, from in vitro experiments to animal studies and human applications. LA - English DB - MTMT ER - TY - JOUR AU - Győrfi, Nina Rubina AU - Gál, Adrián Róbert AU - Fincsur, András AU - Kalmar-Nagy, Karoly AU - Mintál, Kitti AU - Hormay, Edina AU - Miseta, Attila János AU - Tornóczky, Tamás AU - Nemeth, Anita K. AU - Bogner, Péter AU - Kiss, Tamas AU - Helyes, Zsuzsanna AU - Sári, Zoltán AU - Klincsik, Mihály AU - Tadity, Vladimir AU - Lénárd, László AU - Vereczkei, András AU - Karádi, Zoltán György AU - Vizvári, Zoltán Ákos AU - Tóth, Attila TI - Novel Noninvasive Paraclinical Study Method for Investigation of Liver Diseases JF - BIOMEDICINES J2 - BIOMEDICINES VL - 11 PY - 2023 IS - 9 PG - 21 SN - 2227-9059 DO - 10.3390/biomedicines11092449 UR - https://m2.mtmt.hu/api/publication/34124226 ID - 34124226 N1 - Communication AB - Based on a prior university patent, the authors developed a novel type of bioimpedance-based test method to noninvasively detect nonalcoholic fatty liver disease (NAFLD). The development of a new potential NAFLD diagnostic procedure may help to understand the underlying mechanisms between NAFLD and severe liver diseases with a painless and easy-to-use paraclinical examination method, including the additional function to detect even the earlier stages of liver disease. The aim of this study is to present new results and the experiences gathered in relation to NAFLD progress during animal model and human clinical trials. LA - English DB - MTMT ER - TY - JOUR AU - Sarcevic, Péter AU - Csík, Dominik Miklós AU - Pesti, Richárd AU - Stančin, Sara AU - Tomažič, Sašo AU - Tadity, Vladimir AU - Rodriguez-Resendiz, Juvenal AU - Sárosi, József AU - Odry, Ákos TI - Online Outdoor Terrain Classification Algorithm for Wheeled Mobile Robots Equipped with Inertial and Magnetic Sensors JF - ELECTRONICS (SWITZ) VL - 12 PY - 2023 IS - 15 PG - 17 SN - 2079-9292 DO - 10.3390/electronics12153238 UR - https://m2.mtmt.hu/api/publication/34079171 ID - 34079171 N1 - Department of Mechatronics and Automation, Faculty of Engineering, University of Szeged, Szeged, 6725, Hungary Doctoral School of Applied Informatics and Applied Mathematics, Óbuda University, Budapest, 1034, Hungary Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, 1000, Slovenia Institute of Informatics, University of Dunaújváros, Dunaújváros, 2400, Hungary Symbolic Methods in Material Analysis and Tomography Research Group, Faculty of Engineering and Information Technology, University of Pecs, Pecs, 7624, Hungary John von Neumann Faculty of Informatics, Óbuda University, Budapest, 1034, Hungary Facultad de Ingeniería, Universidad Autónoma de Queretaro, Santiago de Querétaro, 76010, Mexico Export Date: 7 November 2023 Correspondence Address: Sarcevic, P.; Department of Mechatronics and Automation, Hungary; email: sarcevic@mk.u-szeged.hu Funding details: 142790 Funding text 1: The work was supported by the National Research, Development, and Innovation Fund of Hungary through project no. 142790 under the FK_22 funding scheme. AB - Terrain classification provides valuable information for both control and navigation algorithms of wheeled mobile robots. In this paper, a novel online outdoor terrain classification algorithm is proposed for wheeled mobile robots. The algorithm is based on only time-domain features with both low computational and low memory requirements, which are extracted from the inertial and magnetic sensor signals. Multilayer perceptron (MLP) neural networks are applied as classifiers. The algorithm is tested on a measurement database collected using a prototype measurement system for various outdoor terrain types. Different datasets were constructed based on various setups of processing window sizes, used sensor types, and robot speeds. To examine the possibilities of the three applied sensor types in the application, the features extracted from the measurement data of the different sensors were tested alone, in pairs and fused together. The algorithm is suitable to operate online on the embedded system of the mobile robot. The achieved results show that using the applied time-domain feature set the highest classification efficiencies on unknown data can be above 98%. It is also shown that the gyroscope provides higher classification rates than the widely used accelerometer. The magnetic sensor alone cannot be effectively used but fusing the data of this sensor with the data of the inertial sensors can improve the performance. LA - English DB - MTMT ER - TY - JOUR AU - Vizvári, Zoltán Ákos AU - Klincsik, Mihály AU - Odry, Péter AU - Tadity, Vladimir AU - Sári, Zoltán TI - General Exact Schemes for Second-Order Linear Differential Equations Using the Concept of Local Green Functions JF - AXIOMS J2 - AXIOMS VL - 12 PY - 2023 IS - 7 PG - 16 SN - 2075-1680 DO - 10.3390/axioms12070633 UR - https://m2.mtmt.hu/api/publication/34037447 ID - 34037447 N1 - Department of Environmental Engineering, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany str. 2, Pecs, H-7624, Hungary Symbolic Methods in Material Analysis and Tomography Research Group, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany str. 6, Pecs, H-7624, Hungary Cellular Bioimpedance Research Group, Szentagothai Research Centre, University of Pecs, Ifjusag str. 20, Pecs, H-7624, Hungary Department of Technical Informatics, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany str. 6, Pecs, H-7624, Hungary Institute of Information Technology, University of Dunaujvaros, Tancsics M. str. 1/A, Dunaujvaros, H-2401, Hungary John von Neumann Faculty of Informatics, University of Obuda, Becsi str. 96/B, Budapest, H-1034, Hungary Export Date: 7 November 2023 Correspondence Address: Vizvari, Z.; Department of Environmental Engineering, Boszorkany str. 2, Hungary; email: vizvari.zoltan@mik.pte.hu AB - In this paper, we introduce a special system of linear equations with a symmetric, tridiagonal matrix, whose solution vector contains the values of the analytical solution of the original ordinary differential equation (ODE) in grid points. Further, we present the derivation of an exact scheme for an arbitrary mesh grid and prove that its application can completely avoid other errors in discretization and numerical methods. The presented method is constructed on the basis of special local green functions, whose special properties provide the possibility to invert the differential operator of the ODE. Thus, the newly obtained results provide a general, exact solution method for the second-order ODE, which is also effective for obtaining the arbitrary grid, Dirichlet, and/or Neumann boundary conditions. Both the results obtained and the short case study confirm that the use of the exact scheme is efficient and straightforward even for ODEs with discontinuity functions. LA - English DB - MTMT ER - TY - JOUR AU - Sári, Zoltán AU - Klincsik, Mihály AU - Odry, Péter AU - Tadity, Vladimir AU - Tóth, Attila AU - Vizvári, Zoltán Ákos TI - Lumped Element Method Based Conductivity Reconstruction Algorithm for Localization Using Symmetric Discrete Operators on Coarse Meshes JF - SYMMETRY (BASEL) J2 - SYMMETRY-BASEL VL - 15 PY - 2023 IS - 5 PG - 24 SN - 2073-8994 DO - 10.3390/sym15051008 UR - https://m2.mtmt.hu/api/publication/33787514 ID - 33787514 N1 - Department of Technical Informatics, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 6, Pecs, H-7624, Hungary Symbolic Methods in Material Analysis and Tomography Research Group, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 6, Pecs, H-7624, Hungary Cellular Bioimpedance Research Group, Szentagothai Research Centre, University of Pecs, Ifjusag Str. 20, Pecs, H-7624, Hungary Institute of Information Technology, University of Dunaujvaros, Tancsics M. Str. 1/A, Dunaujvaros, H-2401, Hungary John von Neumann Faculty of Informatics, University of Obuda, Becsi Str. 96/B, Budapest, H-1034, Hungary Institute of Physiology, Medical School, University of Pecs, Szigeti Str. 12, Pecs, H-7624, Hungary Department of Environmental Engineering, Faculty of Engineering and Information Technology, University of Pecs, Boszorkany Str. 2, Pecs, H-7624, Hungary Cited By :1 Export Date: 7 November 2023 Correspondence Address: Vizvari, Z.; Symbolic Methods in Material Analysis and Tomography Research Group, Boszorkany Str. 6, Hungary; email: vizvari.zoltan@mik.pte.hu AB - The inverse conductivity problem in electrical impedance tomography involves the solving of a nonlinear and under-determined system of equations. This paper presents a new approach, which leads to a quadratic and overdetermined system of equations. The aim of the paper is to establish new research directions in handling of the inverse conductivity problem. The basis of the proposed method is that the material, which can be considered as an isotropic continuum, is modeled as a linear network with concentrated parameters. The weights of the obtained graph represent the properties of the discretized continuum. Further, the application of the developed procedure allows for the dielectric constant to be used in the multi-frequency approach, as a result of which the optimized system of equations always remains overdetermined. Through case studies, the efficacy of the reconstruction method by changing the mesh resolution applied for discretizing is presented and evaluated. The presented results show, that, due to the application of discrete, symmetric mathematical structures, the new approach even at coarse mesh resolution is capable of localizing the inhomogeneities of the material. LA - English DB - MTMT ER - TY - CHAP AU - Csibi, Katalin ED - Vizvári, Zoltán Ákos / Selected by ED - Tóth, Attila / Selected by TI - BIOIMPEDANCIA MONITORING MÉRÉSIADATAINAK NÉPEGÉSZSÉGÜGYI SZEMPONTÚ ELEMZÉSE T2 - SZAKDOLGOZAT ABSZTRAKTKÖTET III. PB - PTE MIK Környezetmérnöki Tanszék CY - Pécs PY - 2019 SP - 6 EP - 8 PG - 3 UR - https://m2.mtmt.hu/api/publication/32590342 ID - 32590342 LA - Hungarian DB - MTMT ER -