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Publications - 6383

On design method of lateral-torsional buckling of beams: State of the art and a new proposal for a general type design method

Bettina Badari F. Papp

Publication Name: Periodica Polytechnica Civil Engineering

Publication Date: 2015-01-01

Volume: 59

Issue: 2

Page Range: 179-192

Description:

After introducing the Eurocode standards several theses have been published on the now much-discussed phenomenon of lateral-torsional buckling of steel structural elements under pure bending. According that, researchers are working on the development of such new design methods which can solve the problems of the design formulae given by the EN 1993-1-1. This paper gives a detailed review on the proposals for novel hand calculation procedures for the prediction of LT buckling resistance of beams. Nowadays, the application of structural design softwares in practical engineering becomes more common and widespread. Recognizing this growing interest, the main objective of our research work is the development of a novel, computer-aided design method. In this paper the details of a general type stability design procedure for the determination of the LT buckling resistance of members under pure bending are introduced. Here, the theoretical basis of the proposed method is clarified, the calculation procedure is detailed and some results for the evaluation of the appropriateness of the method is also presented. Based on the evaluations it can be stated that the new, general type design method is properly accurate and has several advantages on the stability check of beams under bending.

Open Access: Yes

DOI: 10.3311/PPci.7837

An economic prediction of the finer resolution level wavelet coefficients in electronic structure calculations

János Pipek Szilvia Nagy

Publication Name: Physical Chemistry Chemical Physics

Publication Date: 2015-01-01

Volume: 17

Issue: 47

Page Range: 31558-31565

Description:

In wavelet based electronic structure calculations, introducing a new, finer resolution level is usually an expensive task, this is why often a two-level approximation is used with very fine starting resolution level. This process results in large matrices to calculate with and a large number of coefficients to be stored. In our previous work we have developed an adaptively refined solution scheme that determines the indices, where the refined basis functions are to be included, and later a method for predicting the next, finer resolution coefficients in a very economic way. In the present contribution, we would like to determine whether the method can be applied for predicting not only the first, but also the other, higher resolution level coefficients. Also the energy expectation values of the predicted wave functions are studied, as well as the scaling behaviour of the coefficients in the fine resolution limit.

Open Access: Yes

DOI: 10.1039/c5cp01214g

Comparison of Interlimb Coordination During Soccer Instep Kicking Between Elite and Amateur Players

Yaodong Gu Gusztáv Fekete Zixiang Gao Yucheng Wang Zhanyi Zhou Fengping Li Dongxu Wang

Publication Name: European Journal of Sport Science

Publication Date: 2025-09-01

Volume: 25

Issue: 9

Page Range: Unknown

Description:

This study investigates how interlimb joint coordination influences foot speed during soccer instep kicking, using continuous relative phase (CRP) as a quantitative method. The sample includes 15 elite and 15 amateur players to examine potential differences in coordination patterns and their impact on performance. Specifically, we focused on the coordination between hip, knee, and ankle joints in the forefoot-back kicking motion. Results indicated that elite players exhibited significantly higher hip-knee CRP in the coronal plane during 62%–81% of movement duration (p = 0.015) and higher knee-ankle CRP in the vertical plane during 78%–100% (p = 0.013). Moreover, elite players had significantly greater hip-knee mean absolute relative phase (MARP) and deviation phase (DP) in the coronal plane (p < 0.001), as well as increased knee-ankle DP (p = 0.04). In the horizontal plane, hip-knee MARP was also greater in the elite players compared to amateurs (p < 0.001). Further analysis revealed a significant negative correlation between hip-knee CRP and foot velocity in the sagittal plane (R = −0.66, p < 0.001), whereas a significant positive correlation was observed between knee-ankle CRP and foot velocity in the horizontal plane (R = 0.56, p = 0.002). These findings suggest that elite players have superior joint coordination, which contributes to a faster foot velocity at the moment of ball impact. Understanding these coordination patterns provides valuable insights into optimizing kicking techniques. The findings of this study suggest that joint coordination may play an important role in enhancing kicking foot speed, which could inform future training approaches aimed at improving soccer performance.

Open Access: Yes

DOI: 10.1002/ejsc.70041

Effect of Sugarcane Bagasse Ash on the sustainable performance of hot-mix asphalt: A case study of experimental and numerical analysis

Adeyemi Oluwaseun Adeboje Majid Movahedi Rad Udeme Udo Imoh Rauf Hassan Ebunlomo Ruth Adekola

Publication Name: Case Studies in Construction Materials

Publication Date: 2026-07-01

Volume: 24

Issue: Unknown

Page Range: Unknown

Description:

The growing demand for sustainable road infrastructure has intensified the interest in alternative mineral fillers that reduce natural resource consumption and environmental impacts. This study investigates the use of Sugarcane Bagasse Ash (SBA), an abundant agricultural by-product in sub-Saharan Africa, as a partial replacement for conventional mineral fillers in hot-mix asphalt (HMA). Unlike previous studies that considered SBA primarily as a minor additive, this study provides a systematic evaluation across a wide replacement range (0–16 %), combined with experimental testing and numerical validation. Marshall and indirect tensile strength (ITS) tests were conducted on HMA mixtures produced using locally sourced Nigerian aggregates and 60/70 penetration-grade bitumen. A three-dimensional finite element model (FEM) of the ITS configuration was developed to corroborate the experimental response and identify stress concentration zones. results indicate that SBA improves both mechanical and volumetric performance within an optimal replacement range of 6–10 %, with peak performance of approximately 8 % SBA. Within this range, Marshall stability increased from 7.6 kN to 9.0 kN, the Marshall quotient reached 3.3 kN/mm, bulk density increased to 2.51 g/cm³, and air voids decreased from 4.9 % to 3.5 %, remaining within standard design limits. Microstructural analyses confirmed the predominance of amorphous silica and porous SBA morphology, which promoted enhanced filler–binder interactions and mixture densification. FEM predictions of peak tensile stress agreed with laboratory ITS results within 10 % and successfully reproduced observed crack initiation zones. Excessive SBA content (> 10 %) led to reduced stability and density owing to over-filling effects. The findings demonstrate that 6–10 % SBA is a technically viable and sustainable filler replacement for HMA, particularly in sugarcane-producing regions, offering improved performance alongside waste valorization and reduced reliance on quarry-derived fillers.

Open Access: Yes

DOI: 10.1016/j.cscm.2026.e05769

The Vision that Carries the Digital Transformation on Its Back—The Promises of 5G for Sustainability and for the Corporate Sector Focusing on the SMEs in Hungary

Árpád Tóth Áron Gyimesi Gyorgy Wersenyi

Publication Name: Springer Proceedings in Business and Economics

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: 119-144

Description:

Digital transformation, including emerging telecommunication technologies, can be a game changer in the case of SMEs. 5G technology paves the way to substitute different expansive communication technologies, becoming the backbone of i4.0 solutions. Although companies declare the importance of digital transformation, 5G is not necessarily part of it. Especially, SMEs are uncertain about 5G. This paper highlights the business model opportunities and benefits of utilizing this disruptive technology. We analyze the 5G awareness of Hungarian SMEs based on a survey targeting their digital transformation. Hungarian SMEs have significant unawareness regarding the technical issues and the business manners as well. Providing information and guidance based on governmental funding is expected and required.

Open Access: Yes

DOI: 10.1007/978-981-19-8485-3_5

Addressing the Urgent Need for E-scooter Regulation in Hungary

Petra Szakonyi Attila Borsos

Publication Name: Periodica Polytechnica Transportation Engineering

Publication Date: 2026-02-09

Volume: 54

Issue: 2

Page Range: 184-193

Description:

The role of electric scooters is becoming increasingly important for sustainable transport development. E-scooters and other light electric vehicles are generally more efficient in urban environments than electric cars, taking up less road space and resulting in lower energy consumption per trip. Our research involved a systematic literature review to investigate the integration of e-scooters into the existing transport infrastructure network. An online survey was conducted to explore public perceptions and usage patterns of e-scooters, assessing factors such as safety, comfort and preferred speeds. The survey presented five different scenarios in two locations, each illustrating different infrastructure solutions for e-scooters. A total of 137 valid responses were analyzed. Our study showed that infrastructure with dedicated space for bicycles should be preferred for e-scooters. Respondents indicated that the safest solution for e-scooters would be to use the bicycle facility where it is provided followed by the sidewalk, while using the traffic lane received a low rating. There were significant differences in the perception of safety and comfort by different user groups, with cyclists being the only group where we found the smallest deviation in safety and comfort ratings across scenarios. Speed limit preferences for e-scooters also depend on infrastructure provision. Speeds of 15 km/h or less are preferred for sidewalks, 15 km/h or more for bicycle infrastructure, and slightly higher for traffic lanes. In conclusion, our study highlights the need for proactive regulation to address the increasing presence of e-scooters on our existing infrastructure.

Open Access: Yes

DOI: 10.3311/PPtr.40216

Image-Based Estimation of Porosity and Tortuosity in Fibrous Acoustic Absorbers

Krisztián Horváth Attila Schweighardt Krisztián Horváth Krisztián Horváth

Publication Name: Engineering Reports

Publication Date: 2025-12-01

Volume: 7

Issue: 12

Page Range: Unknown

Description:

This study presents a fast and non-destructive image-based method for estimating two key acoustic parameters—open porosity and tortuosity—in fibrous sound-absorbing materials. The approach uses a single grayscale optical micrograph, which is down-sampled, contrast-equalized, and segmented via adaptive thresholding. From the resulting binary fiber mask, two geometric descriptors are extracted: coverage and a one-pixel-wide skeleton. Porosity is estimated using a simple linear formula calibrated on three reference materials, yielding an average absolute error below 0.3% when compared with argon gas pycnometry. Tortuosity is inferred from the total skeleton length relative to the image area, producing a stable ranking across materials with consistent bias relative to measured data. Additionally, a random forest model using only three image features—coverage, median fiber radius, and skeleton length—predicts airflow resistivity with over 70% explained variance. The full analysis pipeline is implemented in Python using open-source libraries (OpenCV, scikit-image) and runs in under half a second per image on standard hardware. This makes the method well suited for early-stage material screening, in-line quality control, or laboratory support, without the need for destructive testing or costly instruments. The approach bridges the gap between optical imaging and physical parameter estimation, offering a lightweight alternative to traditional porosity and impedance-tube measurements.

Open Access: Yes

DOI: 10.1002/eng2.70537

Energy Efficient Drive Management of Lightweight Urban Vehicle

Zoltan Pusztai Ferenc Szauter Ferenc Friedler

Publication Name: Chemical Engineering Transactions

Publication Date: 2023-01-01

Volume: 103

Issue: Unknown

Page Range: 253-258

Description:

In this paper, the energy saving effect of optimized driving strategy is presented and compared to human driving strategy. The driving strategy of a one-seated experimental electric vehicle is investigated and optimized in this study, where the objective function of optimization is the minimization of the consumed energy. Measurement-based vehicle model is used during the optimization process. The initialization and constraints of optimization are set up by analyzing the acquired vehicle data of the driver. The analyzation is done using a transform algorithm, making the initialization of optimization automated. Genetic algorithm is used with mixed initial population acquired from measured driving data and from creation function. Using this hybrid initial population helped to decrease the time of optimization. The resulted velocity profile of the optimized driving strategy was used in field test measurements, where 4.28% energy savings was achieved compared to the results prior to optimization.

Open Access: Yes

DOI: 10.3303/CET23103043

Analysing the Environmental Durability and Chrysotile Content of Asbestos Cement Products by FT-IR Spectroscopy

András Torma Gergely Zoltán Macher Dóra Beke

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 709-714

Description:

The aim of this paper is to examine the environmental resistance and chrysotile content of different asbestos cement products and to prove the relationship between these two factors by analytical results. The paper includes Fourier-transform infrared (FT-IR) spectroscopic analysis of asbestos cement pipes and asbestos cement products with corrugated and flat characteristics. The methodology of the study is based on FT-IR spectroscopy and general statistical approaches, and the results obtained are compared using correlation analysis. The background to the topic is that asbestos cement products are still widely used today despite their harmful effects on health, contrary to European Union asbestos-free targets. A damaged and eroded asbestos cement product loses several grams of asbestos and cement per year from its matrix structure, which is exacerbated by exposure to various environmental influences. The match rate of the chrysotile spectrum for analysed samples has been over 50 % in each case. In the number of measurements, the chrysotile detection rate was 7.64 % higher for degraded and eroded samples. In addition, in the samples exposed to environmental factors, the percentage variance was approximately 10 % or higher, with the exception of asbestos cement pipes. The results provide a basis for situational awareness options. Analytic practitioners, material science researchers, and analysts can use them.

Open Access: Yes

DOI: 10.3303/CET24114119