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Publications - 6374

Experimental confirmation of self-regulating turbulence paradigm in two-dimensional spectral condensation

M. Berta L. Bardóczi L. Schmitz A. Bencze

Publication Name: Physical Review E Statistical Nonlinear and Soft Matter Physics

Publication Date: 2014-12-03

Volume: 90

Issue: 6

Page Range: Unknown

Description:

Turbulent transport in magnetic fusion plasmas can be significantly suppressed by Reynolds-stress-induced zonal flows, allowing effective plasma confinement. We present experimental evidence of spatiotemporal correlation between small-scale turbulence-induced Reynolds stress and large-scale zonal flow production in the E×B driven hydrodynamic spectral condensation. We show that Reynolds stress is generated effectively by anisotropic vorticity structures possessing collective tilt angle. The maximum amplitude of the tilt, the Reynolds stress, and the mean zonal flow production coincide with the transition time of the velocity field, indicating a key role of turbulence-induced Reynolds stress in the condensation of the flow. The analysis of the energy transfer between turbulence and zonal flow shows coherent oscillations with π/2 phase delay, thus indicating a predator-prey-like interaction between zonal flow and turbulence.

Open Access: Yes

DOI: 10.1103/PhysRevE.90.063103

Design, programming and orchestration of heterogeneous manufacturing systems through VR-powered remote collaboration

Tamás Haidegger Péter Galambos Adam Csapo István Marcell Fülöp Péter Zentay Imre J. Rudas Péter Baranyi

Publication Name: Robotics and Computer Integrated Manufacturing

Publication Date: 2015-01-01

Volume: 33

Issue: Unknown

Page Range: 68-77

Description:

Modern manufacturing systems are often composed of a variety of highly customized units and specifically designed manufacturing cells. Optimization of assembly and training of staff requires a series of demo installations and excessive use of costly operational resources. In some cases, components are located at different sites, making the orchestration of the whole system even more difficult. Virtual Reality (VR) collaboration environments offer a solution by enabling high fidelity testing and training of complex manufacturing systems. On the other hand, such platforms are difficult to implement in an engineering perspective, as they are required to provide reliable, standard interfaces towards both robotic components and human operators. The VirCA (Virtual Collaboration Arena) platform is a software framework that supports various means of collaboration through the use of 3D augmented/virtual reality as a communication medium. VirCA offers functions for the high-level interoperability of heterogeneous components in a wide range of domains, spanning from research & development, through remote education to orchestration and management of industrial processes in manufacturing applications. This paper provides an overview of the industrial requirements behind high-fidelity virtual collaboration and demonstrates how the VirCA platform meets these requirements. Use cases are provided to illustrate the usability of the platform.

Open Access: Yes

DOI: 10.1016/j.rcim.2014.08.012

Algorithmic model generation for multi-site multi-period planning of clean processes by P-graphs

Botond Bertok Károly Kalauz Márton Frits

Publication Name: Journal of Cleaner Production

Publication Date: 2024-01-01

Volume: 434

Issue: Unknown

Page Range: Unknown

Description:

Optimal clean process design requires strict constraints to enforce waste and byproduct management, all of which can be formulated in the language of mathematical programming. However, waste management and the utilization of by-products are often carried out in locations or periods other than the production process. The paper describes all modeling steps by P-graphs sufficient to represent raw material availability and production capacities in multiple time periods at multiple sites, as well as transportation and storage capacities of process materials and wastes. These steps are integrated into a single comprehensive model generation algorithm. For easier understanding, each model generation step is illustrated by a case study of planning a multi-site multi-period furniture production process alongside the recent challenges of energy supply and waste management. Finally, the case study of furniture production is analyzed under various circumstances to highlight the power of the proposed tools in daily production and transportation planning. Accordingly, the proposed method provides such alternative 5 best manufacturing and logistics plans that, in the event of a complete failure or overloading of one of the production capacities at either locations, there is still an alternative plan within a 3% profit decrease.

Open Access: Yes

DOI: 10.1016/j.jclepro.2023.140192

The Impact of Digital Transformation on Interpersonal Relationships and Mental Well-Being in Higher Education Institutions

Katalin Czakó Pal Banda

Publication Name: Studies in Systems Decision and Control

Publication Date: 2026-01-01

Volume: 238

Issue: Unknown

Page Range: 941-952

Description:

Digital transformation of higher education institutions has introduced changes in the depth and quality of human interactions that affect both interpersonal relationships and mental well-being. This paper investigates the impact of digitalization on interpersonal relationships and mental well-being within higher education institutions. By delving into Social Support Theory and Social Cognitive Theory, this study assesses the influence of technological advancement on social connections. Through a systematic literature review, this study synthesizes previous research on the benefits and challenges that digital transformation presents in building supportive social networks. Findings indicate that the utilization of new digital platforms and tools might enhance inclusivity, accessibility and flexibility, however, it also negatively affects the development of meaningful interpersonal relationships, which are crucial for maintaining mental well-being. The lack of such strong social bonds was found to be a source of isolation and decreased social cohesion. This study concludes the critical call for balancing digital and in-person interactions. To create a supportive smart university environment, institutions should provide designated digital literacy support and foster a culture that values and encourages meaningful social engagement. This will contribute to interpersonal growth and efficient collaboration and will assist institutions to build more connected academic communities that nurture interpersonal development and social competences, which are vital for cultivating mental well-being.

Open Access: Yes

DOI: 10.1007/978-3-031-85398-2_83

Trains on the Balkan and Eastern Fronts: Front Lines in Hungary during the Great War between 1914 and 1916

Horváth Csaba Sándor Csaba Sándor Horváth

Publication Name: Railways in the First World War Volume 2

Publication Date: 2026-01-01

Volume: 2

Issue: Unknown

Page Range: 28-43

Description:

Historical research into the First World War has a long tradition. There are a number of academic books on the outbreak of the Great War, its battles, human sacrifices and technical innovations. At the same time, there are a number of historians who have specifically studied the role of the railways in the Great War, so there is a significant lack of basic research in this area. The aim of the study is to examine the management, operation, control and social impact of the trains that ran directly along the front lines and through Hungary, which was otherwise unaffected by the frontiers and didn’t become a theatre of war. After the declaration of war on 29 July 1914, the first Hungarian troops were sent to the south, towards Serbia (Balkan Front), and soon afterwards to the north-east, towards the Russian Empire (Eastern Front). The focus of this study is on these two fronts in the first half of the war, between 1914 and 1916, because, in addition to the movement of people, they also carried supplies directly to the Monarchy’s front, while the western and Italian fronts were directly managed by Austria and Germany.

Open Access: Yes

DOI: 10.4324/9781032720722-4

Arbitrary flux waveform generation in scalar hysteresis measurement

Miklós Kuczmann

Publication Name: Pollack Periodica

Publication Date: 2007-12-01

Volume: 2

Issue: 3

Page Range: 3-14

Description:

The aim of the present paper is to show a simple, but well applicable solution to generate arbitrary waveform of magnetic flux density in scalar hysteresis measurements. The paper deals with a possible realization of eliminating the effect of measurement noise as well. First, the measured signals have been transformed into the frequency domain, and after applying digital filter, the spectrum of the filtered signals have been transformed back to the time domain. The proposed technique results in an accurate noise removal algorithm. The paper illustrates a fast controlling algorithm applying the inverse of the actually measured hysteresis loop, and another proportional one to measure any distorted flux pattern. Developing the mentioned algorithms aims the controlling of a more complicated phenomenon, i.e. measuring the vector hysteresis characteristics. © 2007 Akadémiai Kiadó.

Open Access: Yes

DOI: 10.1556/Pollack.2.2007.3.1

Development of Injection Moulded Electromagnetic Pulse Shielded Polymer Cover

Ferenc Ronkay Gabor Dogossy

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 186-193

Description:

Technology for an electromagnetic pulse shielded injection moulded product was developed, using in-mould metal mesh and a 3D printed spacer made of the same type of acrylonitrile-butadiene-styrene as the injection moulded polymer. The functional and mechanical properties of the manufactured flat and dumbbel specimens were tested. The metal mesh increased the stiffness of the plastic, decreased its Charpy impact strength, and did not significantly affect its tensile strength. Computed tomography scans confirmed that delamination and microcracking occur during the failure due to different elongation of the plastic and metal. The attenuation at 1 GHz was 16-19 dB, depending on the metal mesh used. The shielding properties were affected by the fact that the high pressure at the mould filling during the injection moulding process distorted the geometry of the metal mesh.

Open Access: Yes

DOI: 10.3233/ATDE240544

The role of social capital elements: Hungarian winery networks case study

Renata Machova Arpad Branyi László Józsa

Publication Name: Actual Problems of Economics

Publication Date: 2015-01-01

Volume: 170

Issue: 8

Page Range: 100-110

Description:

The main aim of this paper is to present social capital that encourages wine-makers participate in a network and to measure how soft factors such as trust, confidence and regional identity influence network formation. To achieve these goals 8 different wine regions in Hungary are examined. The analysis conducted allows concluding that there is a positive correlation between trust, confidence, regional identity and likeliness of entering or even forming a winery network.

Open Access: Yes

DOI: DOI not available

Human factor aspects of situation awareness in autonomous cars – an overview of psychological approaches

Győző Kurucz Gabor Kovacs Ágnes Hőgye-Nagy

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2021-01-01

Volume: 18

Issue: 7

Page Range: 7-24

Description:

The aim of the article is to give an overview of human factor research in psychology applicable to autonomous driving. The study is centered around situation awareness, a widely used concept in human factor research regarding the operation of automated and semi-automated systems (and communication between autonomous vehicles and humans). A proposal is put forward for structuring situation awareness requirements for autonomous driving, which could be a starting point for defining such requirements, and may foster a discussion on the issues associated with the human factor in relation to autonomous driving. Two models of human error (the SHELL model and the Swiss cheese model) are also introduced, one of which represents an integrated approach of error in situations that involve humans working with complex machinery or instruments, while the other represents a more superficial viewpoint on the multicausal nature of errors. The present overview can provide an appropriate basis for a discussion about the role of the driver in autonomous vehicles, and the place of human factor research in the emerging field of self-driving technology.

Open Access: Yes

DOI: 10.12700/APH.18.7.2021.7.1