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Publications - 6525

Evaluating AMD EPYC CPU architectures on CFD applications

Flavio Cesar Cunha Galeazzo László Környei Łukasz Szustak Paweł Bratek Marcin Lawenda

Publication Name: Future Generation Computer Systems

Publication Date: 2026-04-01

Volume: 177

Issue: Unknown

Page Range: Unknown

Description:

In this work, the authors focus on assessing the impact of the AMD EPYC processor architecture on the performance of CFD applications. Several generations of architectures were analyzed, such as Rome, Milan, Milan X, Genoa, Genoa X and Bergamo, characterized by a different number of cores (64-128), L3 cache size (256 - 1152 MB) and RAM type (8-channel DDR4 or 12-channel DDR5). The research was conducted based on the OpenFOAM application using two memory-bound models: motorBike and Urban Air Pollution. In order to compare the performance of applications on different architectures, the FVOPS (Finite VOlumes solved Per Second) metric was introduced, which allows a direct comparison of the performance on the different architectures. It was noticed that local maximum performance occurs at different values of grid element per CPU when utilizing different processor types. Additionally, the behaviour of the models was analyzed in detail using the AMD µProf and LIKWID software profiling analysis tools to reveal the applications’ interaction with the hardware. It enabled fine-tuned monitoring of the CPU’s behaviours and identified potential inefficiencies in AMD EPYC CPUs. Particular attention was paid to the effective use of L2 and L3 cache memory in the context of their capacity and the bandwidth of memory channels, which are a key factor in memory-bound applications. Processor features were analyzed from a cross-platform perspective, which allowed for the determination of metrics of particular importance in terms of their impact on the performance achieved by CFD applications.

Open Access: Yes

DOI: 10.1016/j.future.2025.108237

Correction to: Response of wheat to combined application of nitrogen and phosphorus along with compost (Journal of Crop Science and Biotechnology, (2022), 25, 5, (557-564), 10.1007/s12892-022-00151-7)

Zoltán Molnár Tibor Janda Lamnganbi Mutum Tagesse Ergudo Wogene Kabato

Publication Name: Journal of Crop Science and Biotechnology

Publication Date: 2022-12-01

Volume: 25

Issue: 5

Page Range: 621

Description:

Due to unfortunate oversight author names have been misspelt.

Open Access: Yes

DOI: 10.1007/s12892-022-00155-3

Dynamics of entanglement after exceptional quantum quench

Ádám Bácsi Balázs Dóra Balázs Dóra

Publication Name: Physical Review B

Publication Date: 2021-02-24

Volume: 103

Issue: 8

Page Range: Unknown

Description:

We investigate a quantum quench from a critical to an exceptional point. The initial state, prepared in the ground state of a critical Hermitian system, is time evolved with a non-Hermitian SSH model, tuned to its exceptional point. The single particle density matrix exhibits supersonic modes and multiple light cones, characteristic of non-Hermitian time evolution. These propagate with integer multiples of the original Fermi velocity. In the long time limit, the fermionic Green's function decays spatially as 1/x2, in sharp contrast to the usual 1/x decay of noninteracting fermions. The entanglement entropy is understood as if all these supersonic modes arise from independent quasiparticles (though they do not), traveling with the corresponding supersonic light cone velocity. The entropy production rate decreases with time and develops plateaus during the time evolution, signaling the distinct velocities in the propagation of nonlocal quantum correlations. At late times, the entanglement entropy saturates to a finite value, satisfying a volume law.

Open Access: Yes

DOI: 10.1103/PhysRevB.103.085137

The Role of Ergonomic Handrails in Inclusive Public Transport: User Aspects, Accident Risks and Design Guidelines †

Balázs Lenkei Rita Földesi

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

Inclusive design is not a design framework provided by legislation, but a design strategy that takes into account the diversity of abilities of users. Ensuring the mobility of people with disabilities is central to their social inclusion, which is why accessibility standards have been developed. Some elements of this are costly (e.g., low-floor vehicles), but simple and cost-effective solutions can make a significant difference in inclusive public transport. This paper uses qualitative methods—interviews, case studies and literature review—to illustrate one of the problem areas, the difficulties of grabs, and one of the potential areas for improvement: grab rails. In non-crash accidents, properly designed handholds play a key role in preserving the integrity of passengers and in creating a sense of physical/psychological safety, contributing to intuitive and independent use and to the social sustainability of public transport.

Open Access: Yes

DOI: 10.3390/engproc2025113058

Article a new approach in determining the decadal common trends in the groundwater table of the watershed of lake “neusiedlersee”

Miklós Arató István Gábor Hatvani Norbert Magyar Balázs Trásy Alfred Paul Blaschke József Kovács

Publication Name: Water Switzerland

Publication Date: 2021-02-01

Volume: 13

Issue: 3

Page Range: 1-17

Description:

Shallow groundwater is one of the primary sources of fresh water, providing river baseflow and root-zone soil water between precipitation events. However, with urbanization and the increase in demand for water for irrigation, shallow groundwater bodies are being endangered. In the present study, 101 hydrographs of shallow groundwater monitoring wells from the watershed of the westernmost brackish lake in Europe were examined for the years 1997–2012 using a combination of dynamic factor and cluster analyses. The aims were (i) the determination of the main driving factors of the water table, (ii) the determination of the spatial distribution and importance of these factors, and (iii) the estimation of shallow groundwater levels using the obtained model. Results indicate that the dynamic factor models were capable of accurately estimating the hydrographs (avg. mean squared error = 0.29 for standardized water levels), meaning that the two driving factors identified (evapotranspiration and precipitation) describe most of the variances of the fluctuations in water level. Both meteorological parameters correlated with an obtained dynamic factor (r = −0.41 for evapotranspiration & r = 0.76 for precipitation). The strength of these effects displayed a spatial pattern, as did the factor loadings. On this basis, the monitoring wells could be objectively distinguished into two groups using hierarchical cluster analysis and verified by linear discriminant analysis in 98% of the cases. This grouping in turn was determined to be primarily related to the elevation and the geology of the area. It can be concluded that the application of the data analysis toolset suggested herein permits a more efficient, objective, and reproducible delineation of the primary driving factors of the shallow groundwater table in the area. Additionally, it represents an effective toolset for the forecasting of water table variations, a quality which, in the view of the likelihood of further climate change to come, is a distinctive advantage. The knowledge of these factors is crucial to a better understanding of the hydrogeological processes that characterize the water table and, thus, to developing a proper water resource management strategy for the area.

Open Access: Yes

DOI: 10.3390/w13030290

Ownership and control in the bus industry: The case of Hungary

John D. Nelson Wafaa Saleh István Prileszky

Publication Name: Journal of Transport Geography

Publication Date: 1997-01-01

Volume: 5

Issue: 2

Page Range: 137-146

Description:

In Hungary, the impending expiry of existing operating licences for both urban and interurban bus services is leading to considerable pressure for change in the current system of ownership and control. Furthermore, the transport sector in Hungary faces several endemic problems. Consequently, this paper analyses the experience of the public transport sector in Hungary with respect to the current situation noting changes after 1990. At the national level, reference is made to both road-based transport (including car ownership and use) and (briefly) to railways. The situation in Budapest is then considered in detail. Next, the structure of the public transport sector in Hungary is discussed both before and after 1990 when the move towards a free market economy received new impetus. The paper examines, as a case-study, the recent experience of private bus operators in Hungary. Finally, drawing on experience elsewhere with possible models for privatization and deregulation in the case of bus operations, suggestions are offered on lessons to be learned by the governments of countries in Central and Eastern Europe as they assess the possibilities for alternative methods of ownership and control. © 1997 Elsevier Science Ltd.

Open Access: Yes

DOI: 10.1016/s0966-6923(97)84102-6

A novel hybrid process design for efficient recovery of hydrophilic ionic liquids from dilute aqueous solutions

Yang Lei Xiaodong Liang Xinyan Liu Yuqiu Chen Rafiqul Gani Georgios M. Kontogeorgis

Publication Name: Aiche Journal

Publication Date: 2023-11-01

Volume: 69

Issue: 11

Page Range: Unknown

Description:

Ionic liquids (ILs) have received much attention in both academia and industries due to their superior performance in many applications. Efficient recovery/recycling of ILs from their dilute aqueous solutions is essential for the acceptance and implementation of many IL-based technologies by industry. In this work, a practical and cost-effective hybrid process design method that combines aqueous two-phase extraction, membrane separation, and distillation operating at their highest efficiencies is proposed for the recovery of hydrophilic ILs from dilute aqueous solutions. The application of this hybrid process design method is illustrated through case studies of recovering two hydrophilic ILs, n-butylpyridinium trifluoromethanesulfonate ([C4Py][TfO]) (CAS number: 390423-43-5) and 1-butyl-3-methylimidazolium chloride ([C4mIm][Cl]) (CAS number: 79917-90-1), from their dilute aqueous solutions. For the recovery of 10 wt.% [C4Py][TfO] from aqueous solution, the hybrid process using (NH4)2SO4 as the salting-out agent could reduce the total annual cost (TAC) and energy consumption by 57% and 91%, respectively, compared with the pure distillation processes. In the case of recovering 10 wt.% [C4mIm][Cl] from aqueous solution, the reduction in TAC and energy savings of the hybrid process with salting-out agent (NH4)2SO3 could reach 49% and 87%, respectively, compared with the pure distillation process. Furthermore, uncertainty analysis through Monte Carlo simulations show that the proposed hybrid process design is more robust to uncertainties in energy prices and other material (e.g., equipment and solvent) costs.

Open Access: Yes

DOI: 10.1002/aic.18198

Synergies between Fuzzy Signatures and Hypergraphs

Csaba Hajdu Ahmet Mehmet Karadeniz Laszlo T. Koczy

Publication Name: Proceedings of the International Symposium on Applied Machine Intelligence and Informatics Sami

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 495-500

Description:

Fuzzy signatures have demonstrated effectiveness in various knowledge-representation domains, including medical decision-making systems and complex decision-making tasks across numerous fields. Even though the advancements in the field of fuzzy signatures have been substantial, the complete potential for developing a comprehensive graph-theoretical description format for this domain still needs to be fully realized. This paper introduces a novel hypergraph-based method for modeling fuzzy signatures, which offers a structured approach to their representation but also showcases the potential synergy between fuzzy signatures and hypergraphs. The proposed method is designed to improve fuzzy information representation and streamline the aggregation-based decision-making process. Future research is anticipated to extend the applicability of this method to control systems and robotics. Furthermore, the hypergraph-based model opens new avenues for the algebraic analysis of fuzzy signatures through tensor-based representations.

Open Access: Yes

DOI: 10.1109/SAMI63904.2025.10883273

Ecological footprint as an indicator of corporate environmental performance—empirical evidence from hungarian smes

Cecilia Szigeti Áron Szennay L. Radácsi J. Lisányi Endréné Beke

Publication Name: Sustainability Switzerland

Publication Date: 2021-01-02

Volume: 13

Issue: 2

Page Range: 1-20

Description:

Small‐ and medium‐sized enterprises (SMEs) play a significant role in the national economies of the EU member states. This economic activity has an inevitable environmental impact; however, environmental performance indicators are mostly measured at larger companies. Since the ecological footprint (EF) is a suitable measure of unsustainability, this paper considers it as a measure of the environmental impact of SMEs. An EF calculator for SMEs was developed that is freely available online, and it is a methodological innovation per se. Our previous research projects highlighted that the calculator must be easy‐to‐use and reliable; therefore, the calculator considers only the common, standardizable, and comparable elements of EF. Our results are based on validated ecological footprint data of 73 Hungarian SMEs surveyed by an online ecological footprint calculator. In order to validate and test the usefulness of the calculator, interviews were conducted with respondents, and results were also checked. The paper presents benchmark data of ecological footprint indicators of SMEs obtained from five groups of enterprises (construction, white‐collar jobs, production, retail and/or wholesale trade, and transportation). Statistical results are explained with qualitative data (such as environmental protection initiatives, business models, etc.) of the SMEs surveyed. Our findings could be used as a benchmark for the assessment of environmental performance of SMEs in Central‐ and Eastern Europe.

Open Access: Yes

DOI: 10.3390/su13021000