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Publications - 6374

Welding distortion generated uncertainties in the vibrational behavior of a ladder-like structure

Publication Name: Proceedings of Inter Noise 2021 2021 International Congress and Exposition of Noise Control Engineering

Publication Date: 2021-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Recent developments in acoustic simulation methods allowed engineers to assess the vibroacoustic behavior of various type of structures within a virtual environment, thus allowing the replacement of prototype-based development with simulations. However, there are some factors, that cannot be considered in simulations in advance. In the present study, the effect of the distortions generated due to welding on a ladder-like structure equipped with flat plates was investigated. The measured acceleration frequency response functions were compared to finite element simulation results. The measured responses differed significantly from the simulation, even in the low frequency ranges, where the global modes were not expected to be altered or vanished. Investigation of the simulated results revealed that the additional modes were related to the vibration of the plates, which were assumed to be flat, instead of considering the warping caused by the welding process. After measuring the approximate deformation of the plates, an updated simulation model was made, introducing an approximate curvature in them. The results obtained with the updated simulation model performed much better in the low frequency range as well as in the third octave-averaged frequency bands up 1200 Hz. The sensitivity of the warping was also systematically evaluated.

Open Access: Yes

DOI: 10.3397/IN-2021-2844

Hyers–Ulam stability of a nonlinear fractional hybrid dynamic equations on arbitrary time scales via measures of noncompactness

Publication Name: Fixed Point Theory and Algorithms for Sciences and Engineering

Publication Date: 2026-12-01

Volume: 2026

Issue: 1

Page Range: Unknown

Description:

This paper investigates different forms of Hyers–Ulam stability for solutions of a nonlinear fractional hybrid dynamic equation defined on arbitrary time scales. By employing the measure of noncompactness together with a newly developed generalized version of Darbo’s fixed-point theorem, the existence of solutions is established. The uniqueness of solutions is further guaranteed via the Banach fixed-point theorem. In addition, illustrative numerical examples are presented to demonstrate the applicability and effectiveness of the theoretical results.

Open Access: Yes

DOI: 10.1186/s13663-026-00839-3

ESG factors in M&A in India: Performance and market insights from 2010 to 2023

Publication Name: Investment Management and Financial Innovations

Publication Date: 2024-01-01

Volume: 21

Issue: 2

Page Range: 310-322

Description:

This study assesses the impact of mergers and acquisitions on Environmental, Social, and Governance (ESG) performance and market value of acquiring companies operating in India. Data were collected and analyzed from 69 M&A announcements from January 2010 to June 2023, sourced from the Bloomberg database. The analysis reveals a positive correlation between the post-merger market value of acquiring firms and their ESG performance, indicating that an improvement in ESG factors is associated with increased market value after mergers. Additionally, a positive correlation was identified between acquiring companies’ post-merger ESG performance and their target firms’ pre-merger ESG performance. This finding suggests that when acquiring a target firm with high ESG performance, the acquirer is likely to experience an improvement in its own post-merger ESG performance. Moreover, both the post-merger market value and ESG performance of the acquirer are likely to improve with the profitability and size of firms but will have a negative impact based on the leverage components of the acquiring firms.

Open Access: Yes

DOI: 10.21511/imfi.21(2).2024.25

Improved Equations of the Classic Hunting Problem of Railway Wheelsets

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 240-247

Description:

In this paper, the equations of motion are derived for a railway wheelset by the systematic linearisation of the full nonlinear description. Compared to the standard approximate equations of the literature, the new form of differential equations improves the values of some coefficients and also adds the correct values of terms from gravity and gyroscopic forces. The resulting model can be used to describe the stability loss called hunting motion, and can be included in models of whole railway vehicles.

Open Access: Yes

DOI: 10.3233/ATDE240551

Doping Prevalence in Sport from Indirect Estimation Models: A Systematic Review and Meta-analysis

Publication Name: Sports Medicine Open

Publication Date: 2026-12-01

Volume: 12

Issue: 1

Page Range: Unknown

Description:

Background: To our knowledge, no previous systematic review and meta-analysis of doping prevalence in sport from indirect estimation models (IEM) exists. Objective: To conduct a systematic review and meta-analysis of empirical IEM-based studies of admitted doping prevalence in sport. Methods: We conducted electronic database and ad hoc searches up to March 2025, and estimated lifetime and past year prevalence rates through a cross-classified model including prevalence (lifetime vs. past year), sample (competitive vs. recreational) and sports (multi-sport vs. single-sport) types. Results: Forty-six records (K) were included in the review (k [subset records included in the meta-analysis] = 30, n [independent studies from the records] = 34). The World Anti-Doping Agency’s definition of doping use was applied for data collection in most studies (k = 18), and doping prevalence was mostly assessed as past year/season (k = 20). Studies included in the meta-analysis were mostly conducted in Europe (k = 22) and applied the Unrelated Question (k = 8) and Forced Response with Cheater Detection (k = 6) models. Study participants were mostly multi-sport (k = 20) and competed at diverse levels, and most data (k = 28) was collected outside sport events. The corpus included articles that re-analysed existing data (k = 4). Lifetime prevalence was highest for multi-sport competitive athletes (22.6%) and lowest for single-sport competitive athletes (12.7%), whereas past year prevalence was highest for single-sport recreational sportspersons (15.5%) and lowest for multi-sport recreational sportspersons (8.7%). Conclusions: Under IEM, about one of five multi-sport competitive athletes admitted to ever doping whereas about one of six of single-sport recreational sportspersons admitted to doping in the past year. Furthermore, multi-sport (vs. single-sport) competitive athletes show relatively higher doping prevalences, whereas single-sport (vs. multi-sport) recreational sportspersons report relatively higher doping prevalences. Secondary (re-)analysis presents a novel methodological challenge for meta-analyses. Registration PROSPERO: CRD42022373691.

Open Access: Yes

DOI: 10.1186/s40798-026-01014-z

Modeling of radial magnetic bearing by finite element method

Publication Name: Pollack Periodica

Publication Date: 2011-08-01

Volume: 6

Issue: 2

Page Range: 13-24

Description:

The paper presents the numerical modeling of a Y-shaped three-pole radial magnetic bearing based on two-dimensional (2D) and three-dimensional (3D) magnetic field computation with nonlinear model of the material. The used numerical method is the Finite Element Method (FEM). The nonlinear system of equations according to the nonlinear characteristics of ferromagnetic material can be handled by the Newton-Raphson technique and by the fixed-point method.

Open Access: Yes

DOI: 10.1556/Pollack.6.2011.2.2

Investigation of the Load-Bearing Capacity of Resin-Printed Components Under Different Printing Strategies

Publication Name: Applied Sciences Switzerland

Publication Date: 2025-08-01

Volume: 15

Issue: 15

Page Range: Unknown

Description:

This study examines the influence of different printing orientations and infill settings on the strength and flexibility of components produced using resin-based 3D printing, particularly with masked stereolithography (MSLA). Using a common photopolymer resin and a widely available desktop MSLA printer, we produced and tested a series of samples with varying tilt angles and internal structures. To understand their mechanical behavior, we applied a custom bending test combined with high-precision deformation tracking through the GOM ARAMIS digital image correlation system. The results obtained clearly show that both the angle of printing and the density of the internal infill structure play a significant role in how much strain the printed parts can handle before breaking. Notably, a 75° orientation provided the best deformation performance, and infill rates between 60% and 90% offered a good balance between strength and material efficiency. These findings highlight how adjusting print settings can lead to stronger parts while also saving time and resources—an important consideration for practical applications in engineering, design, and manufacturing.

Open Access: Yes

DOI: 10.3390/app15158747

Numerical analysis of magnetized Ag-Fe3O4/VPO hybrid nanofluid flow over a spinning inclined disc with Thompson–Troian slip

Publication Name: Discover Nano

Publication Date: 2026-12-01

Volume: 21

Issue: 1

Page Range: Unknown

Description:

Magnetized hybrid nanofluid (HNF) flow across a spinning inclined disc (SID) under Thompson–Troian slip (TTS) conditions has numerous applications. It can help improve the efficiency of cooling systems in electrical appliances by optimizing lubricant flow and energy transportation. In the current work, we have studied the HNF flow over a SID under multiple slip conditions in the form of partial differential equations (PDEs). The black iron oxide (Fe3O4) or Iron (II, III) oxide, along with silver (Ag) nanoparticles (NPs), is mixed with vacuum pump oil (VPO) for the preparation of HNF. The fluid flow is investigated in relation to nonlinear heat radiation, viscous dissipation, mixed convection, Joule heating, and irregular heat source/sink. The system of PDEs is first converted into a non-dimensional form of ODEs and then solved numerically through the BVP4c technique. It has been determined that the flow rate of HNF (Ag and Fe3O4/VPO) declines with the variation of Ag and Fe3O4 NPs in VPO, and the magnetic field parameter. The fluid temperature distribution declines with the influence of NPs' volume friction. By varying the NPs volume friction (Ag and Fe3O4-NPs) from 0.01 to 0.03, the coefficient of Nusselt number (energy transfer rate) increases up to 31.6401%. Physically, Ag and Fe3O4 NPs in VPO have a high thermal conductivity, which more efficiently boosts the energy transfer rate and is more applicable to the cooling systems and energy transportation.

Open Access: Yes

DOI: 10.1186/s11671-026-04664-w

Perceived university support and environment as a factor of entrepreneurial intention: Evidence from Western Transdanubia Region

Publication Name: Plos One

Publication Date: 2023-06-01

Volume: 18

Issue: 6 June

Page Range: Unknown

Description:

The exploration of entrepreneurship has become a priority for scientific research in recent years. Understanding this phenomenon is particularly important for the transformation of entrepreneurship into action, which is a key factor in early-stage entrepreneurial activity. This gains particular relevance in the university environment, where, in addition to the conventional teaching and research functions, the entrepreneurial university operation based on open innovation, as well as the enhancement of entrepreneurial attitudes of researchers and students, are receiving increased attention. This study is based on a survey conducted among students attending a Hungarian university of applied science in Western Transdanubia Region who have demonstrated their existing entrepreneurial commitment by joining a national startup training and incubation programme. The main research question of the study is to what extent student entrepreneurship intention is influenced by the environment of the entrepreneurial university ecosystem and the support services available at the university. A further question is whether these factors are able to mitigate the negative effects of internal cognitive and external barriers by enhancing entrepreneurial attitudes and perceived behavioural control. The relatively large number of students involved in the programme allows the data to be analysed using SEM modelling. The results indicate a strong covariance between the perceived university support and environment among students. Another observation is the distinct effect of these institutional factors on perceived behavioural control of students.

Open Access: Yes

DOI: 10.1371/journal.pone.0283850