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Publications - 6374

Alternative Supply of the Mineral Raw Material Needs of the Asphalt Industry by Metallurgical Slags

Szabolcs Fischer Laszlo Ezsias

Publication Name: Periodica Polytechnica Transportation Engineering

Publication Date: 2026-02-09

Volume: 54

Issue: 2

Page Range: 138-149

Description:

With the growing demand for high-quality raw materials in the asphalt industry, finding sustainable alternatives to natural aggregates has become increasingly important. This study explores the potential of using metallurgical slags – specifically, blast furnace slag (BFS) and converter slag (CS) – as substitutes for traditional materials like basalt and andesite in asphalt mixtures. Through a series of laboratory tests, we examined the performance of these slag-based mixtures in terms of stiffness, water resistance, deformation, and durability under thermal stress. The results were promising that both BFS and CS met or even exceeded standard technical requirements. CS showed superior stiffness and aging resistance, likely due to its alkaline properties that slow down bitumen degradation. Slag-based mixtures also demonstrated strong skid resistance and maintained their mechanical properties better than natural aggregates when exposed to extreme temperature changes. These findings suggest that incorporating metallurgical slags into asphalt production could help address raw material shortages while offering environmental benefits, such as reducing CO2 emissions and preserving natural resources. With comparable or even better performance than traditional aggregates, slag-based asphalt mixtures present a viable and sustainable option for the future of road construction.

Open Access: Yes

DOI: 10.3311/PPtr.40489

Study on a road surface estimation method based on big data analysis

Balazs Nemeth Dániel Pup Daniel Fenyes Peter Gaspar Ferenc Szauter

Publication Name: Saci 2019 IEEE 13th International Symposium on Applied Computational Intelligence and Informatics Proceedings

Publication Date: 2019-05-01

Volume: Unknown

Issue: Unknown

Page Range: 57-62

Description:

The paper presents a new method to classify the road surfaces according to the adhesion coefficient between the tire and road surface using big data approach. In this research, three different categories of the road surface are considered, such as dry, wet and icy. The purpose of classification is to create a model, which is able to determine the type of the actual road surface using only the measured data of the vehicle. The classification method is, basically, based on the C4.5 decision tree algorithm, while the data is provided the high-fidelity simulation software, CarSim. Finally, the efficiency of the resulted model is demonstrated through a complex simulation.

Open Access: Yes

DOI: 10.1109/SACI46893.2019.9111487

Understanding the Role of PBAT Content and Raster Orientation on the Mechanical Performance of Material Extrusion 3D-Printed PLA/PBAT Objects

László Lendvai András Lajos Nagy Sándor K. Jakab

Publication Name: Polymers

Publication Date: 2026-02-01

Volume: 18

Issue: 3

Page Range: Unknown

Description:

Poly(lactic acid) (PLA) is the most widely used feedstock in material extrusion (MEX) 3D printing. In this study, PLA was combined with 0–40 wt.% of poly(butylene adipate-co-terephtalate) (PBAT) to improve its ductility. The resulting blends were processed into filaments suitable for MEX 3D printing and used to fabricate specimens for mechanical characterization using three distinct raster angles (RAs; 0°, ±45°, and 90°) to statistically evaluate the individual and joint effects of blend composition and raster orientation. Melt flow index (MFI) measurements showed that increasing PBAT content reduced the MFI from 40.4 g/10 min to 34.4 g/10 min, which led to weaker bonding between printed beads, as shown in scanning electron microscopic images. Tensile strength, modulus, and impact strength were evaluated using tensile and Charpy tests. Statistical analysis showed that RA, PBAT concentration, and their interaction all significantly influenced (p < 0.05) mechanical performance. Both strength and modulus decreased as PBAT content and RA increased, with the highest values of 50 MPa and 2.78 GPa observed for neat PLA 3D-printed at 0° RA, and the lowest values of 15 MPa and 1.05 GPa for 40 wt.% PBAT at 90° RA. In contrast, incorporating PBAT improved impact strength, showing its toughening effect. Meanwhile, no clear trend between impact resistance and RA was observed. The highest impact strength (52.7 kJ/m2) was found at 40 wt.% PBAT content and ±45° RA.

Open Access: Yes

DOI: 10.3390/polym18030339

The development of mathematical competences in hungarian teacher training education

Szilvia Petz Miklós Hoffmann

Publication Name: Annales Mathematicae Et Informaticae

Publication Date: 2017-01-01

Volume: 47

Issue: Unknown

Page Range: 243-251

Description:

In this paper we present research results on the assessment of K1-4 (pupils from age 7 to age 10) teacher training student’s mathematical knowledge and competences as one of the most important parameters of school teaching quality. Teachers’ abilities in grades K1-4 are among the most important in-school factors influencing the quality of pupils’ learning. A large-scale longitudinal study was conducted in which the elementary mathematical knowledge and skills of a group of teacher training students from 5 different institutes was assessed by means of a paper and pencil test that was administered both at the beginning and at the end of their second year mathematical course in the 2016/2017 academic year. This course is a methodical course in some institutions, which has an essential influence on the final results of this research. The 27-item-test covered the new standards for mathematics in the K1-4 elementary school curriculum. We have observed that those students coming from institutions providing separate methodical courses can gain better knowledge in explaining simple mathematical relations and notions than those students whose institutions do not provide methodical background in specific courses.

Open Access: Yes

DOI: DOI not available

THE END OF AN ERA

Andor Wesselényi-Garay

Publication Name: Metszet

Publication Date: 2023-01-01

Volume: 14

Issue: 6

Page Range: 34-39

Description:

Today's innovation will help to inform the future's tradition or 01vice versa. Drawing inspiration from traditional and regional Transylvanian architectural forms a new residential building has been developed to house trainee ice hockey players. The building itself although described as traditional, merely a reference to its external appearance, is seen to innovative in the use of building technology and mechanical services on closer inspection.

Open Access: Yes

DOI: 10.33268/Met.2023.6.3

Combined Effect of Nano Ferrite and Nano Silica on Properties of Cement Mortar

Rasha R. Rawdhan Azhar J. Bohan Ghaed K. Salman Muhanad Al-Jubouri

Publication Name: International Journal of Integrated Engineering

Publication Date: 2024-01-01

Volume: 16

Issue: 1

Page Range: 350-360

Description:

This study investigates the effects of adding nano-ferrite (N.F.) and nano-silica (N.S.) on the mechanical and biological properties of mortar. By assessing four water-to-cement ratios (1–4%), the ideal nanoparticle doses were determined. Results indicated that both N.F. and N.S. significantly increased the mortar’s strength at ratios between 1% and 4%, while combinations of N.F. and N.S. improved strength up to 3% and 4% substitution, respectively. The mechanisms of strength enhancement were attributed to nanoparticles acting as fillers and hydration accelerators, which densify the mortar microstructure and promote the production of calcium silicate hydrate (C-S-H) gels. In terms of biological properties, the study examined the antibacterial effects of nano-silica and nano-ferrite. Nano-silica demonstrated greater antibacterial potency against all bacterial strains assessed. Both materials exhibited a stronger antibacterial impact on Gram-positive bacteria (Staphylococcus aureus) compared to Gram-negative bacteria (Escherichia coli), due to differences in cell wall structures. The study emphasizes the importance of optimal nanoparticle dosages and identifies limitations that warrant further research, such as durability and potential downsides at higher concentrations. Despite these challenges, the findings underscore the potential of nanoparticles to enhance mortar performance and suggest promising applications in construction and the development of antibacterial materials. Future research should focus on overcoming these constraints and exploring the practical applications of nanoparticle-enhanced mortar in real-world scenarios.

Open Access: Yes

DOI: 10.30880/IJIE.2024.16.01.030

Investigation of the Effects of Thermit Welding on the Mechanical Properties of the Rails

Szabolcs Fischer B. Kocsis Dóra Harangozó Vivien Barna András Brautigam

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2022-01-01

Volume: 19

Issue: 3

Page Range: 37-49

Description:

This current paper deals with the investigation of the variation of the hardness of the rail steel material in the heat-affected zone (HAZ) of a rail joint made by thermit welding (TW). The tested rail is a normal R260 type rail steel category; its production date is 1977, the rolling mill was Diosgyor (Hungary), rail profile is MÁV 48.5. This rail has not been in railway track before the test. The authors performed hardness tests on the rail head’s surface even after the rail welding, as well. After the welding and hardness tests, the rail joint was cut with +/–200 mm by a rail cutter and transported to the laboratory. Water jet cutting was applied to shape six longitudinal direction slices with five vertical cutting lines from the rail piece’s head. The slices’ length was 400 mm, the width of these slices was approx. 10 mm; the TW rail joint was in the mid-point of the slices. Micro-Vickers (HV10) hardness tests were executed on these slices, in the –150…+150 mm interval lengthwise and in the 3, 6, and 10 mm depth points below the rail head’s top surface. As a result, the authors received a very detailed hardness functions of the HAZ of rail joint made by TW. These variation functions were compared to the official Elektrothermit’s SoW-5 hardness tests’ results. It can be concluded that the variation of the hardness of rail steel in the area of the HAZ correlated with the Elektrothermit’s results; however, there were some critical points where significant differences were able to be found. The highest deviation was concluded in 50 mm distance measured from the axis of welded rail joint. The authors gave possible valuable explanations for these phenomena.

Open Access: Yes

DOI: DOI not available

Multiple hypothesis testing by unpaired samples for indexing changepoints in a road-induced vibration signal

László Róbert Hári

Publication Name: UPB Scientific Bulletin Series D Mechanical Engineering

Publication Date: 2021-01-01

Volume: 83

Issue: 3

Page Range: 17-28

Description:

Several methods have been developed for simulating non-stationary and non-Gaussian processes in packaging vibration testing, encompassing unique methods for the segmentation of road vehicle vibrations. However, only a limited number of those consider spectral characteristics. Thus, the current paper introduces a novel segmentation algorithm conducted in the time-frequency domain. The spectral characteristics obtained by short-time Fourier transform are compared by multiple hypothesis tests to find changepoints in a wheeled vehicle vibration sample. Different post hoc procedures are introduced against the inflating Type I. error.

Open Access: Yes

DOI: DOI not available

Green Energy–Related Financial Literacy for Environmentally Sustainable Development

Csongor Czipf Absalón J. Salmerón- Zapata José G. Vargas- Hernandez

Publication Name: Materials Techniques and Ecological Impact of Sustainable Prototyping

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: 269-300

Description:

In the framework of ecologically sustainable development, this research paper explores the crucial relationship between financial literacy and the use of green energy. The study looks into how institutional and individual financial knowledge affects choices about energy-efficient technology, sustainable financial products, and investments in renewable energy. This paper highlights important gaps in green energy financial literacy that impede the shift to sustainable energy systems by thoroughly analyzing the body of existing literature, actual data, and theoretical frameworks. The study uses a mixed-methods approach, combining qualitative interviews with policymakers and industry professionals with quantitative surveys of 2,500 respondents from a range of demographic categories. Important findings show that although 78% of respondents are generally aware of the advantages of green energy, only 32% of them are sufficiently knowledgeable about green investments, tax breaks, financing options, and long-term cost-benefit evaluations.

Open Access: Yes

DOI: 10.4018/979-8-3373-5473-6.ch008