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Publications - 6374

Advanced Numerical Simulation of Scour around Bridge Piers: Effects of Pier Geometry and Debris on Scour Depth

Muhanad Al-Jubouri Ethar H. Abbas R. P. Ray

Publication Name: Journal of Marine Science and Engineering

Publication Date: 2024-09-01

Volume: 12

Issue: 9

Page Range: Unknown

Description:

Investigating different pier shapes and debris Finteractions in scour patterns is vital for understanding the risks to bridge stability. This study investigates the impact of different shapes of pier and debris interactions on scour patterns using numerical simulations with flow-3D and controlled laboratory experiments. The model setup is rigorously calibrated against a physical flume experiment, incorporating a steady-state flow as the initial condition for sediment transport simulations. The Fractional Area/Volume Obstacle Representation (FAVOR) technique and the renormalized group (RNG) turbulence model enhance the simulation’s precision. The numerical results indicate that pier geometry is a critical factor influencing the scour depth. Among the tested shapes, square piers exhibit the most severe scour, with depths reaching 5.8 cm, while lenticular piers show the least scour, with a maximum depth of 2.5 cm. The study also highlights the role of horseshoe, wake, and shear layer vortices in determining scour locations, with varying impacts across different pier shapes. The Q-criterion study identified debris-induced vortex generation and intensification. The debris amount, thickness, and pier diameter (T/Y) significantly affect the scouring patterns. When dealing with high wedge (HW) debris, square piers have the largest scour depth at T/Y = 0.25, while lenticular piers exhibit a lower scour. When debris is present, the scour depth rises at T/Y = 0.5. Depending on the form of the debris, a significant fluctuation of up to 5 cm was reported. There are difficulties in precisely estimating the scour depth under complicated circumstances because of the disparity between numerical simulations and actual data, which varies from 6% for square piers with a debris relative thickness T/Y = 0.25 to 32% for cylindrical piers with T/Y = 0.5. The study demonstrates that while flow-3D simulations align reasonably well with the experimental data under a low debris impact, discrepancies increase with more complex debris interactions and higher submersion depths, particularly for cylindrical piers. The novelty of this work lies in its comprehensive approach to evaluating the effects of different pier shapes and debris interactions on scour patterns, offering new insights into the effectiveness of flow-3D simulations in predicting the scour patterns under varying conditions.

Open Access: Yes

DOI: 10.3390/jmse12091637

Automatic ELM detection and study of statistical ELM properties by Li-BES on COMPASS

M. Berta P. Háček J. Krbec M. Szutyányi R. Somers M. Hron R. Pánek A. Bencze V. Weinzettl

Publication Name: 46th Eps Conference on Plasma Physics Eps 2019

Publication Date: 2019-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

No description provided

Open Access: Yes

DOI: DOI not available

Examining the relationship between physical activity and sleep among university students

Róbert Járai Feifei Wang Nikoletta Barka Róbert Járai Szilvia Boros

Publication Name: Frontiers in Sports and Active Living

Publication Date: 2025-01-01

Volume: 7

Issue: Unknown

Page Range: Unknown

Description:

Objective: Physical activity and adequate sleep are essential for health and wellbeing. University students face distinct challenges affecting their habits. This study investigates sociodemographic impacts on physical activity and sleep patterns, and examines the association between physical activity and sleep quality in Hungarian university students. Methods: An online cross-sectional survey was conducted among students (N = 1,340, mean age 20.00 ± 1.59 years; 60.7% female and 39.3% male) from the Budapest University of Economics and Business. The survey was based on sociodemographic data, the Hunarian version of the International Physical Activity Questionnaire-Short Form (IPAQ-SF), and the Pittsburgh Sleep Quality Index (PSQI) questionnaires. In IPAQ-SF, respondents indicated physical activities lasting at least 10 min during the last seven days. Responses were categorised by WHO and IPAQ guidelines. Metabolic Equivalent of Task (MET) was calculated. Statistical analyses were conducted using IBM SPSS Statistics 29.0.0.0, with significance set at p < 0.05. Results: Most participants (85.8%–86.9%) performed below the WHO recommendations for moderate-intensity physical activity. Significant sex differences were noted in physical activity levels (p < 0.001 for vigorous intensity; p < 0.043 for moderate intensity), with men being more active than women. Regarding sleep quality, 57.1% of participants reported good sleep quality (PSQI 0–5), 36.1% had moderate sleep disturbances (PSQI 6–10), and 6.8% experienced poor to severe sleep disturbances (PSQI 11–21). Women reported significantly poorer sleep quality than men did (p < 0.001). Multiple linear regression analysis revealed a significant interaction between energy expenditure on physical activity and sports participation frequency (β = −0.09, p = 0.012), indicating that regular sports participation may buffer against potential negative effects of high overall physical activity on sleep quality. The model explained 3.1% of the variance in sleep quality (R2 = 0.031, p < 0.001). Conclusion: The relationship between physical activity (MET-minutes/week) and sleep quality was moderated by the frequency of sports participation. Given that poor sleep can negatively impact academic performance, health, and well-being, these findings support the promotion of organized sports within university settings. Interventions targeting both physical activity and sleep hygiene may yield synergistic benefits, particularly for students with sedentary lifestyles.

Open Access: Yes

DOI: 10.3389/fspor.2025.1640770

Fuzzy communication and motion control by fuzzy signatures in intelligent mobile robots

Tamás D. Gedeon Áron Ballagi Ĺaszĺo T. Ḱoczy

Publication Name: Studies in Computational Intelligence

Publication Date: 2009-10-26

Volume: 241

Issue: Unknown

Page Range: 147-164

Description:

This paper presents two examples for the deployment of fuzzy signatures in the field of intelligent mobile robots. The first shows a complex lateral drift control method base on fuzzy signatures. This method considers the motion system of the robot as a whole, unlike as simple parts of a complex system. The state space is written down by fuzzy signatures which add up flexibility, adaptability and learning ability to the system. In the second experiment a new communication approach is investigated for intelligent cooperation of autonomous mobile robots. Effective, fast and compact communication is one of the most important cornerstones of a high-end cooperating system. In this paper we propose a fuzzy communication system where the codebooks are built up by fuzzy signatures. We use cooperating autonomous mobile robots to solve some logistic problems. © 2009 Springer-Verlag Berlin Heidelberg.

Open Access: Yes

DOI: 10.1007/978-3-642-03633-0_9

Association of Production and Selected Dimensional Conformation Traits in Holstein Friesian Cows

Szabolcs Bene Gabriella Holló László Bognár Zsolt J. Kőrösi Ferenc Szabó

Publication Name: Animals

Publication Date: 2024-09-01

Volume: 14

Issue: 18

Page Range: Unknown

Description:

The objective of this study was to estimate the heritability of dairy production traits and that for dimensional traits and to calculate the correlation between the two heritability values in a Holstein Friesian cow herd bred in Hungary. Data of 15,032 Holstein Friesian cows born in the period 2008–2018 from 666 sires were collected for the study in 6 large dairy herds. Among the conformation traits, stature (ST), chest width (CW), body depth (BD), and rump width (RW), and for production traits, in the first lactation of cows, the 305-day milk yield (MY), milk butterfat yield (FY), and milk protein yield (MY) were evaluated. Heritability estimates of ST, CW, BD, and RW were 0.49, 0.25, 0.31, and 0.30, and those of MY, FY, and PY were 0.40, 0.35, and 0.30, respectively. BD and RW had no phenotypic (b = −0.01) or genetic (b = 0.00–0.01) change. The production traits (MY, FY, PY) increased to a greater extent (b = 2.2–43.3) than the examined conformation traits over time. Consequently, it is indicated that the selection for dairy production did not result in an increase in the studied dimensional traits.

Open Access: Yes

DOI: 10.3390/ani14182753

MILP models for the optimization of real production lines

Tamás Hajba Zoltán Horváth

Publication Name: Central European Journal of Operations Research

Publication Date: 2015-12-01

Volume: 23

Issue: 4

Page Range: 899-912

Description:

A special class of the permutation flow shop problems (PFSPs) with makespan minimization which contains repeated jobs, limited buffer sizes between the machines and fixed number of palettes that carry the jobs on the production line is introduced in this paper. We define the related PB-R-PFSP, the Permutation with Repetition Flow Shop Problem with Palettes and Buffers, and construct new mixed integer linear programming (MILP) models for this problem. The effectiveness of the MILP models and the influence of the number of palettes and buffers on the problems are investigated experimentally.

Open Access: Yes

DOI: 10.1007/s10100-014-0337-8

A Decade in Hijacked Journals: What Will be the Future Trend?

Lóránt Dávid Mehdi Dadkhah Mihály Hegedűs

Publication Name: Advanced Pharmaceutical Bulletin

Publication Date: 2024-01-01

Volume: 14

Issue: 4

Page Range: 722-728

Description:

Purpose: Hijacked journals are fraudulent websites that mimic legitimate journals and, by charging authors, publish manuscripts. The current editorial endeavors to provide a close view of current literature. This editorial piece analyzes 10 years of research on hijacked journals and endeavors to shed light on future trends. Methods: Current research uses a bibliometric approach to analyze data and discuss results. The OpenAlex has been used for data collection. Some of the data analysis was conducted using OpenAlex. The other study was done using Bibliometrix, and the date is limited to publication between 2014 and 2024. Results: The findings provide a close view of the published literature in terms of access type, growth, topics, most frequent words, country contribution, top publishers, and alignment of literature with sustainable development goals. Conclusion: The gap in current literature is the limitation in easily usable methods to be accessible by all researchers for hijacked journal detection and data analysis. The use of artificial intelligence can be promising.

Open Access: Yes

DOI: 10.34172/apb.44002

Population Genetic Features of Calving Interval of Holstein-Friesian Cows Bred in Hungary

Szabolcs Bene J. Péter Polgár László Bognár Zsolt J. Kőrösi Ferenc Szabó

Publication Name: Animals

Publication Date: 2024-09-01

Volume: 14

Issue: 17

Page Range: Unknown

Description:

Calving interval (CI) data (N = 37,263) from 17,319 cows born 2008–2018 in six herds were assessed. The data were made available by the National Association of Hungarian Holstein Friesian Breeders in Hungary. The effects of some genetic and environmental factors, population genetic parameters, breeding value (BV) of sires, and phenotypic and genetic trends of the CI were estimated. The GLM method was used for studying different effects on the CI. BLUP animal model was used for heritability (h2) and BV estimation. Linear regression analyses were applied for the trend calculation. The mean of the CI was 412.2 ± 2.0 days. The h2 of the CI proved to be low (0.07 ± 0.01 and 0.08 ± 0.01). There were relatively high differences among the sires in the estimated BV. Based on the phenotypic trend calculation, the CI of cows showed decreasing direction by an average of 1.80 days per year (R2 = 0.94; p < 0.01). In the case of genetic trend calculation, the average BV of sires in the CI has decreased −4.94 and −0.31 days per year (R2 = 0.91 and 0.41; p < 0.01).

Open Access: Yes

DOI: 10.3390/ani14172513

Thermal examination of a simplified exhaust tube-heatshield model

Balázs Vehovszky Tamás Jakubík Marcell Treszkai

Publication Name: Periodica Polytechnica Transportation Engineering

Publication Date: 2019-01-01

Volume: 47

Issue: 3

Page Range: 190-195

Description:

Exhaust system and its surrounding is a thermally highly critical part of a vehicle: during forced operation, hottest elements can reach 600 °C. The thermal conditions turn to even more critical if the forced flow leaves off – e.g. when the car stops at a highway parking place. In such a case not only the cooling effect of cross-flow disappears, but the natural convection starts to bring heat toward nearby elements – resulting potential overheating of concerned parts. A measurement setup for modelling such case was built, and different parameters were examined, which have influence on the heating of aluminium heatshield above the exhaust tube. Measurements were complemented by CFD simulations and flow visualization technique aiming the better understanding of evolving thermal and flow conditions.

Open Access: Yes

DOI: 10.3311/PPtr.12109