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Found 6289 publications

Development of Magnetic Hysteresis Loop Measurement System for Characterization of 3D-Printed Magnetic Cores

Tamas Orosz Miklos CSIZMADIA Tamás Horváth

Publication Name: Electronics Switzerland

Publication Date: 2025-06-01

Volume: 14

Issue: 11

Page Range: Unknown

Description:

Today, numerous advanced options exist for analyzing and measuring magnetic hysteresis loops and core loss across a broad spectrum of applications. Most of these systems are compact and ready to use, fulfilling the measurement and data processing requirements for laminated iron cores according to the standards. However, modeling newly developed materials with complex structures or the high-frequency behavior of iron cores, and the computation of dynamic hysteresis properties’ temperature dependence, are still challenging problems in the field. Moreover, these standardized measurement tools are relatively expensive, and most of them represent a black box that impedes research and further development. This paper presents the development of a cheap and accessible measurement system that is explicitly designed for recording the hysteresis properties of 3D-printed iron cores. The paper presents a comprehensive overview of the design process, components, circuitry, and simulations integral to this project. The paper presents a completed circuit simulation conducted using LTspice and validation of the prototype’s measurement performance. The measurements obtained with the proposed system show good agreement with those of the reference setup, demonstrating its accuracy and practical applicability.

Open Access: Yes

DOI: 10.3390/electronics14112235

A novel method for structural strength modeling of lamination stacks of electric motors using contact in FEA

Viktor Szabó Korbinian Weber

Publication Name: Results in Engineering

Publication Date: 2025-06-01

Volume: 26

Issue: Unknown

Page Range: Unknown

Description:

The automotive industry is transforming from traditional internal combustion drive systems to alternative ones, mostly based on electric motors. Fueled by strict requirements and high competition on the market, simulation has become an essential part of the development process. The precise structural strength simulation of rotors is extremely difficult, as a consequence of the nonlinear mechanical behavior of the lamination stack. Due to computational limits, this part has traditionally been simulated as a solid structure with orthotropic linear material models. These models were not capable of accurately simulating the axial nonlinear stiffness, the separation / slip of individual sheets or their plastic deformations. The method presented in this article does not have these limitations. By using a stacked shell approach, simulating all of the sheets separately using a contact model developed especially for this purpose, the method can be used to model real rotors using a fair amount of computational resources. The new method contributes significantly to the precision of virtual tests of rotors used in electric drives.

Open Access: Yes

DOI: 10.1016/j.rineng.2025.104699

Metamodel-based Optimization of Anisotropic Rotor Axial Flux Permanent Magnet Synchronous Motors

Miklós Kuczmann Attila Nyitrai

Publication Name: Periodica Polytechnica Electrical Engineering and Computer Science

Publication Date: 2025-01-01

Volume: 69

Issue: 1

Page Range: 89-98

Description:

Axial flux motors have some significant advantages over radial flux motors in high torque-density applications. However, the optimization of axial flux permanent magnet synchronous motors is a challenging task; the analysis usually requires 3D finite element analysis or the application of the 2D multi-slice method. In this paper a novel single-surrogate multi-slice method (SS-MSM) is proposed for modeling anisotropic rotor axial flux permanent magnet motors. However, the general methodology can be applied to other axial flux motors as well. A model calibration methodology has been described where the SS-MSM parameters have been determined using a 2D finite element approach as a reference. The SS-MSM was found to be suitable for a fast and reasonably accurate approximation of the motor performance. Based on the described analysis method, an efficient optimization approach is proposed.

Open Access: Yes

DOI: 10.3311/PPee.36813

Partition deactivation with load balancing for parallel flow simulations

József Bakosi

Publication Name: Journal of Computational Physics

Publication Date: 2024-12-15

Volume: 519

Issue: Unknown

Page Range: Unknown

Description:

An algorithm is presented to save CPU time by dynamically deactivating partitions of a decomposed computational mesh during parallel flow simulations. The procedure targets classes of problems where the propagation behavior, inherent in the equations solved, can be exploited, such as detonation or scalar transport. Combined with dynamic load balancing based on real-time CPU-measurement, available, e.g., by coding the solver using the Charm++ runtime system, yields considerable savings in solution times for both shared-, and distributed-memory calculations. The complete source code is available at https://xyst.cc.

Open Access: Yes

DOI: 10.1016/j.jcp.2024.113387

Investigation of CO2 Emission Concerning Levee Reinforcement Technologies

Edina Koch Zoltán Major Cecília Szigeti

Publication Name: Lecture Notes in Civil Engineering

Publication Date: 2025-01-01

Volume: 580 LNCE

Issue: Unknown

Page Range: 1-10

Description:

Flooding is one of the primary causes of losses from natural disasters in numerous regions worldwide, surpassing all other types of natural hazards in terms of damage. In recent decades, flood damage has been significantly severe due to the increase in the frequency and intensity of floods. Considering that levees are built for an established design life, it is essential to consider potential changes in loads due to atmospheric climate change. Climate variability may affect hydraulic loading and soil eroding with significant precipitation or during drought or high wind conditions. These atmospheric changes over time may affect the structural integrity of the levee. The dominating failure modes for typical ground conditions along rivers are slope stability, overtopping, through seepage, and underseepage. Several technologies can be applied to prevent levee failure, strengthen the levee, avoid overtopping or internal erosion, and ground subsidence due to changing groundwater. The most common ones are concrete columns, sheet piles, geosynthetics, and deep mixing using different binders. However, these technologies come out to be costly, in terms of materials. Moreover, the primary material of these interventions is cement. Nowadays, it is accepted that the cement industry is one of the two largest producers of carbon dioxide (CO2). The Sustainable Development Goals (SDGs) provide comprehensive guidelines for promoting sustainable development in terms of environmental, social, and economic dimensions in all sectors of the economy, including civil engineering. The study outlines the procedure to calculate the carbon dioxide emissions of different technologies for levee reinforcement. Considering a simple scenario, the technical suitability of the investigated technologies is analyzed, and the carbon dioxide emission is analyzed separately.

Open Access: Yes

DOI: 10.1007/978-981-96-1873-6_1

Bacterial memetic algorithm for fuzzy rule base optimization

Cristiano Cabrita János Botzheim Tamás D. Gedeon Carlos Fonseca António E. Ruano László T. Kóczy

Publication Name: 2006 World Automation Congress Wac 06

Publication Date: 2006-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In our previous works model identification methods were discussed. The bacterial evolutionary algorithm for extracting a fuzzy rule base from a training set was presented. The LevenbergMarquardt method was also proposed for determining membership functions in fuzzy systems. The combination of evolutionary and gradient-based learning techniques - the bacterial memetic algorithm - was also introduced. In this paper an improvement of the bacterial memetic algorithm is shown for fuzzy rule extraction. The new method can optimize not only the rules, but can also find the optimal size of the rule base. Copyright - World Automation Congress (WAC) 2006.

Open Access: Yes

DOI: 10.1109/WAC.2006.376057

Heat treatment parameters effecting the fractal dimensions of AuGe metallization on GaAs

Csaba Dominkovics János Pipek László Dobos Gábor Harsányi Imre Mojzes Szilvia Nagy

Publication Name: Applied Physics Letters

Publication Date: 2007-08-24

Volume: 91

Issue: 7

Page Range: Unknown

Description:

Correlation was detected between the thermal treatment parameters of the AuGe-GaAs system and surface fractal structure. Structural entropic calculations were used to confirm the results obtained by fractal calculations. © 2007 American Institute of Physics.

Open Access: Yes

DOI: 10.1063/1.2768911

School Streets: Transforming Urban Spaces for Safer Student Commuting

Petra Szakonyi Emese Mako

Publication Name: Lecture Notes in Networks and Systems

Publication Date: 2026-01-01

Volume: 1768 LNNS

Issue: Unknown

Page Range: 66-71

Description:

This study provides a comprehensive review of the concept of School Streets, emphasising their role in enhancing traffic safety, accessibility, and community well-being. By analysing successful implementations across several European cities, practical strategies and interventions were identified that facilitate the transformation of urban spaces around schools into safer, child-friendly environments. This is the first study to evaluate the feasibility of School Streets in Hungary through on-site assessments of 30 schools, providing locally grounded, evidence-based recommendations for context-specific implementation. Additionally, the research assesses the feasibility of establishing School Streets in Hungary by examining 30 local schools, considering factors such as existing infrastructure, community needs, and potential obstacles. Tailored recommendations are developed to support policymakers and urban planners in designing and implementing context-specific solutions. The findings underscore the significant benefits of School Streets in reducing traffic hazards, promoting active mobility, and fostering healthier, more engaged communities. Ultimately, this work advances sustainable and child-centric urban mobility practices, offering practical insights for creating safer, more inclusive school environments across Hungary and Europe.

Open Access: Yes

DOI: 10.1007/978-3-032-13898-9_7

Multidimensional comparison of life cycle footprint of hydrogen production technologies

András Torma A. Zseni Péter Németh

Publication Name: Cleaner Engineering and Technology

Publication Date: 2025-02-01

Volume: 24

Issue: Unknown

Page Range: Unknown

Description:

Hydrogen as an energy carrier will play an important role in the future in achieving sustainable development goals in the energy and mobility sectors as well as to reach decarbonization goals. Currently adopted hydrogen strategies foresee a significant increase in the amount of hydrogen used in the future. To meet this increased volume in the most sustainable way, a careful analysis of potential hydrogen production technologies is necessary, considering real environmental impacts. This paper provides a comprehensive overview of different non-renewable and renewable hydrogen production technologies and evaluates their environmental effects based on global warming potential (GWP). Environmental footprint data discussed in this paper are based on published life-cycle assessment (LCA) results. As direct comparison of LCA results is difficult due to different LCA scenarios, selected system boundaries, various material components and manufacturing techniques, a novel multidimensional comparison approach was developed to understand LCA results better and to give a more comprehensive picture of environmental footprint components. In addition to methodological issues, the key influencing factors of the carbon footprint of different hydrogen production technologies were also identified. It is not possible to identify one stand-alone technology that would be the most environmentally friendly in all circumstances, it is essential to investigate all the technologies in the given context of use. Regarding water-splitting, it is outstandingly crucial to examine the source of the electricity because it strongly influences the GWP of this H2 production technology. If the GWP of the electricity is high, this technology could be more harmful to the environment than the steam methane reforming (SMR).

Open Access: Yes

DOI: 10.1016/j.clet.2025.100902