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Publications - 6374

Input parameters of transdanubian clay for the hardening soil and soft soil models

Edina Koch

Publication Name: Pollack Periodica

Publication Date: 2009-04-01

Volume: 4

Issue: 1

Page Range: 93-104

Description:

In recent years, finite element modeling has become an important design tool. Advanced programs make it possible to use more complex soil models in addition to standard elasto-plastic models with Mohr-Coulomb failure criteria. These new models can follow nonlinear behavior and complicated loading sequences. The two most promising new models are: the Hardening Soil Model (HS) and the Soft Soil Model (SS). This paper focuses on the behavior of Transdanubian Clay, common in Hungary. Sampling, laboratory testing, and evaluation of data aiming at determining parameters for HS and SS models are described. Results based on oedometer tests using unloading/reloading sequences proved to be adequate for input to these models. © 2009 Akadémiai Kiadó.

Open Access: Yes

DOI: 10.1556/Pollack.4.2009.1.10

The effective reduction of spurious oscillations in the valve closure event of an internal combustion engine

Daniel Serfozo

Publication Name: Journal of Physics Conference Series

Publication Date: 2026-01-01

Volume: 3190

Issue: 1

Page Range: Unknown

Description:

The accurate numerical solution of contact-impact problems using finite element method is challenging in multiple aspects. The main difficulty is the effective attenuation of spurious oscillations emerging due to the spatial discretization. As these oscillations deteriorate the accuracy, the elimination of spurious components in the numerical results has a great importance. To achieve it, a damping effect must be contained in the applied numerical scheme. Based on the conducted research in this field, the concrete shape of the damping character plays a crucial role in reducing oscillations with the best possible efficacy. The proposed method operates with viscous damping formulated as Caughey damping. Considering concrete industrial problems, represented as a two-dimensional FEM model, the proposed scheme proved to be effective and more accurate compared to several widely applied numerical methods. Due to the simple formulation combined with good oscillations reduction, the newly developed method has a great potential in practical engineering applications.

Open Access: Yes

DOI: 10.1088/1742-6596/3190/1/012004

The role of driver's eye height in the design of crest curves of roads

Dániel Miletics Khalil Khaska

Publication Name: Pollack Periodica

Publication Date: 2023-09-25

Volume: 18

Issue: 3

Page Range: 113-118

Description:

The driver's eye height from the ground, as what drivers can see on the road, is essential for their safety and for avoiding road hazards. Using the statistical analysis of vehicles sample, the statistical parameters of the measured set of values were determined. A one-sample t-test was done to check whether the measured sample differs from the driver's eye height value specified in the Hungarian design guidelines. A new range of driver's eye height has been found, which is considered an update to the current value and might be applied in the upcoming road design. Parallel with the eye-height analysis, sight distances at vertical crest curves were modeled by AutoCAD Civil 3D. The minimum radiuses of the crest curves were defined for human eye height and for sensors of autonomous vehicles.

Open Access: Yes

DOI: 10.1556/606.2023.00808

Comparative study on credibility measures of type-2 and type-1 fuzzy variables and their application to a multi-objective profit transportation problem via goal programming

Dipak Kumar Jana Palash Sahoo Ĺaszĺo T. Ḱoczy

Publication Name: International Journal of Transportation Science and Technology

Publication Date: 2017-06-01

Volume: 6

Issue: 2

Page Range: 110-126

Description:

In real world applications supply, demand and transportation costs per unit of the quantities in multi-objective transportation problems may be hardly specified accurately because of the changing economic and environmental conditions. It is also significant that the time required for transportation should be minimized. In this paper, we have presented three reduction methods for a type-2 triangular fuzzy variable (T2TrFV) by adopting the critical value (CV). Three generalized expected values (optimistic, CV and pessimistic) are derived for T2TrFVs with some special cases. Then a multi-objective profit transportation problem (MOPTP) with fixed charge (FC) cost has been formulated and solved in type-2 fuzzy environment. Unit transportation costs, FC, selling prices, unit transport times, loading and unloading times, total supply capacities and demands are all considered as triangular Type-2 fuzzy numbers. The MOPTP has been converted into a single objective by using the goal programming technique and the weighted sum method. The deterministic model is then solved using the Generalized Reduced Gradient method Lingo 14.0. Numerical experiments with some sensitivity analysis are illustrated the application and effectiveness of the proposed approaches.

Open Access: Yes

DOI: 10.1016/j.ijtst.2017.06.002

Tracking the shift from health to harm: Development and validation of a short screening tool for orthorexia nervosa (STONE)

Andrea Petróczi Elizabeth Pummell Hilda Mulrooney Elina Mitrofanova

Publication Name: Appetite

Publication Date: 2025-10-01

Volume: 214

Issue: Unknown

Page Range: Unknown

Description:

Orthorexia Nervosa (ON), a problematic fixation on healthy eating, has captured researchers' attention for over a decade. We aimed to develop a brief screening tool for ON that captures physical appearance as a motivating factor, behavioural aspects (rigid control over food selection, consumption and preparation), and nutritional aspects (avoidance of foods considered “impure”). Using a sequential, iterative design, 687 participants completed a self-reported survey across four studies: item identification and selection through exploratory factor analysis (n = 248), testing factorial construct validity with confirmatory factor analysis (n = 127), discriminant validity via known group differences (n = 241), and test-retest reliability of two subsequent administrations of the selected items (n = 71). The final unidimensional version of the short Screening Tool for Orthorexia Nervosa (STONE) comprises eight items. It demonstrated excellent known-group validity and ability to differentiate ON from other types of strict dietary control (e.g., health-based or religious restrictions). Consistent with the view of ON as behaviours aimed at rigid dietary control, avoidance of “impure” foods, and motivation to enhance physical appearance, STONE scores positively related to measures of eating pathology and appearance orientation, while only weakly correlating with obsessive-compulsive tendencies. Based on its psychometric properties, STONE is recommended as a first-level screening tool for ON in research contexts and epidemiology studies among adults. Due to its brevity, it can be easily combined with other scales to explore ON or related phenomena. Future studies should examine convergent validity and test it among adolescents and in different cultural contexts.

Open Access: Yes

DOI: 10.1016/j.appet.2025.108227

Malta's low carbon transition towards sustainability

Yuriy Bilan Brian Azzopardi Rafał Kasperowicz Marcin Pinczynski Dalia Streimikiene

Publication Name: Sustainable Development

Publication Date: 2024-10-01

Volume: 32

Issue: 5

Page Range: 5120-5128

Description:

The transition to low-carbon energy and energy independence of a country play an important role in the sustainable development of its energy sector. Another important issue of sustainable energy development is the cost competitiveness in the generation process; with new renewable energy technologies, a sustainable energy transition to carbon-neutral society is possible. In this article, we present a view of sustainable energy transformation based on a case study of Malta. We have created a simulation of a Maltese electricity system with projected growth and dominance of photovoltaic energy in the electricity market. The study results suggest that a system with a high penetration of photovoltaics has significant advantage over a conventional system using fossil fuels. In particular, in the simulated Maltese system, the total annual cost of energy was reduced threefold, the CO2 emissions were reduced by 40%, and the energy independence of Malta increased by 60%. In the end, the article gives a recommendation for further research into the Maltese energy system.

Open Access: Yes

DOI: 10.1002/sd.2967

Fuzzy flip-flop based neural network as a function approximator

László Gál Rita Lovassy Ĺaszĺo T. Ḱoczy

Publication Name: Cimsa 2008 IEEE Conference on Computational Intelligence for Measurement Systems and Applications Proceedings

Publication Date: 2008-09-26

Volume: Unknown

Issue: Unknown

Page Range: 44-49

Description:

Artificial neural networks and fuzzy logic systems, in the context of approximate reasoning, share common features and techniques. A family of fuzzy flip-flops is proposed, based on an artificial neural network-like structure which is suitable for approximating many-input one-output nonlinear functions. The neurons in the multilayer perceptron networks typically employ sigmoidal activation functions. The next state of the fuzzy J-K flip-flops (F3) using Yager and Dombi operators present quasi-S-shaped characteristics. The paper proposes the investigation of the possibility of constructing multilayer perceptrons from such fuzzy units. Each of the two candidates for F 3-based neurons is examined for its training capability by evaluating and comparing the approximation properties in the context of different transcendental functions with one-input and multi-input cases. Simulation results are presented. ©2008 IEEE.

Open Access: Yes

DOI: 10.1109/CIMSA.2008.4595830

The spatial dimension of liturgy: Historical and contemporary accounts of communio-space in Europe's Latin rite liturgical architecture

Vilmos Katona

Publication Name: Epites Epiteszettudomany

Publication Date: 2017-03-01

Volume: 45

Issue: 1-2

Page Range: 173-213

Description:

The present study focuses on the spatial aspect of the liturgy, the raison d'être of church building. The topicality of this approach is explained either by the manner of international communication about sacred architecture, or by the work of German architect Rudolf Schwarz (1897-1961), who is cited anew, very often due to his unification of architectural praxis, scientific activity and a life of a devoted man deservedly still influential in the field. A church can be understood by its operative function. Throughout the most important liturgical reform movements of the 20th century, one can get an insight into the spatial concepts of the designers, which, consciously or not, reflect the achievements of these movements even today. In the contemporary praxis of Latin Rite liturgy, the divorce between the once close-knit aspects of the worship are palpable, thanks to these reforms on the one hand, and their late interpretations on the other. Inspired by autonomous readings, the sacrificial act of the Eucharist (sacrificium) and the symbol of the communal feast (cena) were associated with correspondent models of space. This problem shares root with the frequent contraposition of personal devotion and the communio: the former prevails in oriented spaces, while the latter appears in the central. Spatial concepts capable of respecting both religious devotion and the needs of the community in their primordial unity and theological profoundness, seldom can be found today. Following the terminology of Albert Gerhards and Walter Zahner, these are often referred to as communio-spaces (Communio-Räume). Albeit the proposition of this space type is clearly theoretical, it looks back to important antecedents from the 20th century, and defines a multiplicity of new directions. The story of communio-space spans from Rudolf Schwarz to the contemporary church architecture of Central and Western Europe as well as North America, and still influences the newest designs of liturgical spaces. In Hungary, this recent issue of spatial arrangement is not a question of a substantial debate up to now, yet even this limited number of experiments necessitate the idea and applied examples of communio-space to acquire more attention here as well.

Open Access: Yes

DOI: 10.1556/096.2017.45.1-2.9

Juvenile court – the Conqueror of Legal History

Enikő Kovács-Szépvölgyi

Publication Name: Journal on European History of Law

Publication Date: 2022-01-01

Volume: 13

Issue: 1

Page Range: 156-160

Description:

The idea of the title that the juvenile court is the greatest conqueror of legal history comes from a work by renowned criminal lawyer Ferenc Finkey, who quoted Hastings H. Hart’s thoughts about the juvenile court. The Juvenile Court first appeared in Illinois, USA, in 1899, followed by most federal states and several countries on the old continent. The state-and legal life of Hungary, in the broader context of the Central and Eastern European states, is usually interpreted in the framework of the centre-periphery model. Without going into the issue of regulatory delay, it is worth noting that Hungarian legislation caught up with pioneering states with special criminal law regulations introduced in the early 20th century to establish the foundations for other treatment of juvenile offenders. The different treatment in this context refers to different rules from those for adult offenders. The law regulating the juvenile court as a special court entered into force in 1914, supplementing the substantive criminal law provisions with procedural rules.

Open Access: Yes

DOI: DOI not available