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Publications - 6374

Computing behind the iron curtain and beyond Hungarian national perspective

Maria Raffai

Publication Name: IFIP International Federation for Information Processing

Publication Date: 2006-12-04

Volume: 215

Issue: Unknown

Page Range: 153-165

Description:

At the beginning of the computing era it was a great challenge to write a running program in order to solve different mathematical, statistical tasks, and to get the appropriate results by using a computer. At the university where I had began my studies we started to get acquainted with computers using a Russian made machine, named URAL 2. Looking back to the roots and thinking of the Hungarian born pioneer of computer science: the polymath John von Neumann, I had intended to deal with the history of computing at the very beginning of the eighties. Although there is a wide range of computing history literature worldwide (most of them in English), there are not any publications dealing with the Hungarian results. As I was one of the first graduates on computing taught by the Pioneers, I am forced to perform research on all materials dealing with the Hungarian achievements in computing, to protect the values of the past as long as it is not too late and also to make the results known!. © 2006 International Federation for Information Processing.

Open Access: Yes

DOI: 10.1007/978-0-387-34741-7_11

Phylogenetic re-evaluation of previously identified Chlamydomonas (Chlorophyta, Chlamydomonadaceae) strains from The Mosonmagyaróvár Algal Culture Collection, Hungary, using molecular data

K. Szenthe H. D. Laughinghouse Péter Bálint B. Pap Gergely Maróti Zoltán Molnár D. E. Berthold S. Katona C. Kilgore N. Horváth Vince Ördög F. Bánáti L. Vörös

Publication Name: South African Journal of Botany

Publication Date: 2019-09-01

Volume: 125

Issue: Unknown

Page Range: 16-23

Description:

Systematic studies on 70 MACC isolates previously identified as ‘Chlamydomonas’, a unicellular flagellate, were carried out based on partial 18S rRNA. The aim of this study was to determine the phylogenetic affiliations of Chlamydomonas strains in the MACC collection. The study found that most of the strains were not Chlamydomonas. Nine clusters of phylogenetically similar taxa were identified. The previous determinations were completed with their new phylogenetic affiliations (partly due to changes in green algae classification). Molecular data revealed that 3 of the 70 strains are from Arenicolinia, 14 are members of the phylogroup Stephanosphaerinia, 11 are Oogamochlamydinia, 1 is Chloromonadinia, 19 are Reinhardtinia, 2 are Polytominia, 9 are Scenedesmaceae, 5 are Moewusinia, and 6 are Chlorella. Clades were established by 18S rRNA similarity and p-distances. This study reveals the need to revise established culture collections whose isolates are solely identified with morphology.

Open Access: Yes

DOI: 10.1016/j.sajb.2019.06.028

Exploring economic development and mineral rents nexus across BRICS nations: Fresh insights from multiple threshold panel analysis

Mandeep Mahendru Elżbieta Roszko-Wójtowicz Sanjeet Singh Pooja Bansal Meenu Bhardwaj

Publication Name: Resources Policy

Publication Date: 2024-01-01

Volume: 88

Issue: Unknown

Page Range: Unknown

Description:

The nexus between economic development and mineral rent across Brazil, Russia, India, China, and South Africa (BRICS) is empirically tested by using multiple threshold panel analysis. This paper focuses on the association and correlation among Mineral Rents (% of GDP) and Gross Domestic Product per capita along with Foreign Direct Investment (FDI), Trade, and Renewable Energy Consumption per Capita, by using the data sets for the period 1994–2021. Dynamic Liner Model and Double Threshold models are used for empirical testing of the above variables. The Dynamic Liner Model identified the positive influence of trade and FDI on mineral rent; and the Double Threshold models identified the negative influence of GDP, trade, and FDI on mineral rent. The findings contribute to the literature about mineral rent and economic growth. Moreover, the findings of this paper help in planning policies and interventions for inclusive and sustainable economic development, GDP enhancement, promotion of trade, and FDI in Brazil, Russia, India, China, and South Africa (BRICS) by considering mineral rent management. This paper also recommends considering the mineral rent taxation, mineral royalty, mine-community conflicts, corruption, institutional development, politics, and environmental issues before policy implementation and reforms related to economic development, GDP enhancement, promotion of trade, and FDI in BRICS.

Open Access: Yes

DOI: 10.1016/j.resourpol.2023.104537

A Test Model for Hardware and Software Systems

Jozsef Sziray

Publication Name: Journal of Advanced Computational Intelligence and Intelligent Informatics

Publication Date: 2004-09-01

Volume: 8

Issue: 5

Page Range: 523-529

Description:

The paper is concerned with the general aspects of testing complex hardware and software systems. First a mapping scheme as a test model is presented for an arbitrary given system. This scheme serves for describing the one-to-one correspondence between the input and output domains of the system, where the test inputs and fault classes are also involved. The presented test model incorporates both the verification and the validation schemes for hardware and software. The significance of the model is that it alleviates the clear differentiation between verification and validation tests, which is important and useful in the process of test design and evaluation. On the other hand, this model provides a clear overview on the various purpose test sets, which helps in organizing and applying these sets. The second part of the paper examines the case when the hardware and software are designed by using formal specification. Here the consequences and problems of formal methods, and their impacts on verification and validation are discussed.

Open Access: Yes

DOI: 10.20965/jaciii.2004.p0523

Determination of rail dilatation movements at tunnel gates for ballasted railway tracks in case of a greater change of temperature

Szabolcs Fischer Nándor Liegner

Publication Name: Acta Technica Jaurinensis

Publication Date: 2026-05-27

Volume: 19

Issue: 2

Page Range: 137-154

Description:

The temperature change in continuously welded rail (CWR) tracks induces substantial internal stresses and shifts sleeper positions because the rails are longitudinally restrained from thermal expansion. This phenomenon is significantly intensified at tunnel portals, where a sharp contrast exists between the thermal boundary conditions of the open track and those of the sheltered tunnel environment. The current article investigates the dynamic interplay between rail dilatation and axial forces at these critical junctions by employing a finite-element (FE) model of the 54E1 rail track, calibrated using experimental measurements of track fastening parameters and ballast behavior. The research specifically examines the combined influence of temperature gradients between the tunnel and open environments, the bilinear longitudinal resistance of the ballast, and the mechanical braking loads exerted by passing trains. Through a series of parametric studies, the results demonstrate that simultaneous thermal and braking forces can trigger extreme rail displacements of up to 100 mm and axial forces of up to 1.4 MN. Notably, such high-stress states occur even when the ballast resistance is only 7 N/mm lower than the braking force. While increasing track fastening resistance helps equalize the impact of braking and thermal effects, it effectively reduces deflections to non-critical levels. The most severe stability risks are identified when the center of the braking zone aligns precisely with the portal. Ultimately, the study concludes that ballast resistance is the decisive factor in managing track integrity at tunnel entrances.

Open Access: Yes

DOI: 10.14513/actatechjaur.00875

An economic prediction of refinement coefficients in wavelet-based adaptive methods for electron structure calculations

János Pipek Szilvia Nagy

Publication Name: Journal of Computational Chemistry

Publication Date: 2013-03-05

Volume: 34

Issue: 6

Page Range: 460-465

Description:

The wave function of a many electron system contains inhomogeneously distributed spatial details, which allows to reduce the number of fine detail wavelets in multiresolution analysis approximations. Finding a method for decimating the unnecessary basis functions plays an essential role in avoiding an exponential increase of computational demand in wavelet-based calculations. We describe an effective prediction algorithm for the next resolution level wavelet coefficients, based on the approximate wave function expanded up to a given level. The prediction results in a reasonable approximation of the wave function and allows to sort out the unnecessary wavelets with a great reliability. © 2012 Wiley Periodicals, Inc.

Open Access: Yes

DOI: 10.1002/jcc.23154

Modelling of virtualized servers

Akos Kovacs Gábor Lencse

Publication Name: 2015 38th International Conference on Telecommunications and Signal Processing Tsp 2015

Publication Date: 2015-10-09

Volume: Unknown

Issue: Unknown

Page Range: 241-245

Description:

The virtualized systems are one of the key elements of the next generation IT infrastructures. Modeling it will prevent mistakes, and oversized management. Opennebula is one of the most current open source cloud management solutions. Together with Haizea, they are a powerful tool to model and manage a virtualized infrastructure trough the API of Openebula. Haizea has multiple scheduler algorithms that are more effective than that of Opennebula. We performed several experiments to compare simulation and measurement capabilities of Haizea and we highlighted some difference between them which can be reduced if required.

Open Access: Yes

DOI: 10.1109/TSP.2015.7296260

Recycling plastic waste into fiberglass formwork: a durable, sustainable, and cost-effective construction solution

Nurullah Bektaş Samuel Alexandro Silitonga

Publication Name: Clean Technologies and Environmental Policy

Publication Date: 2026-05-01

Volume: 28

Issue: 5

Page Range: Unknown

Description:

The global waste crisis poses significant environmental challenges, with Southeast Asia being a major contributor to solid waste. Medan, Indonesia’s third largest city, is facing environmental challenges due to large amounts of plastic waste and was considered the dirtiest metropolitan city of Indonesia based on the assessment of the Ministry of Environment and Forestry and the Adipura 2020 program. This study proposes a sustainable approach by transforming plastic waste into fiberglass, a durable composite material, to produce fiberglass formwork, providing a sustainable alternative to traditional wooden formwork, since wooden formwork contributes to deforestation and environmental concerns. Building upon existing literature that separately reports the feasibility of producing fiberglass from plastic waste, and the utilization of fiberglass for formwork manufacturing, this study seeks to establish a direct link between plastic waste management and fiberglass formwork production. The objectives include evaluating its material potential, cost-effectiveness, productivity, and life cycle performance compared to wooden formwork. Results demonstrate that fiberglass formwork offers superior durability, dimensional stability, water resistance, 80% quicker installation, and extended lifespan up to 10 times longer than wooden formwork. This translates to cost-effectiveness by 54%, improved construction efficiency, and life cycle assessments show significant ecological cost and carbon footprint advantages, highlighting its environmental sustainability. This novel approach not only addresses plastic waste management but also reduces deforestation, aligning with global sustainability goals. Fiberglass formwork thus presents a compelling case for adoption in environmentally responsible construction practices.

Open Access: Yes

DOI: 10.1007/s10098-026-03486-9

Mechanics and energetics, the complex analysis of an industrial problem with the tools of up-to-date computer methods

I. Zsenak J. Egert F. Zsenak

Publication Name: Proceedings of the Conference on Mechanical Engineering

Publication Date: 1998-12-01

Volume: 2

Issue: Unknown

Page Range: 805-810

Description:

The arc furnaces are widely used to melt different kind of materials on high temperature. In the steel and the aluminum factories the so-called gurgling type Heroult furnaces are used. The shell's geometry an the used arc's parameters are the function of the local expectations. The most of the arcs agree on that the water taking up released heat during the melting goes out to channels or cooling towers, leaving the energy non-utilized.

Open Access: Yes

DOI: DOI not available