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Dissipative dynamics in the free massive boson limit of the sine-Gordon model

Ádám Bácsi Balázs Dóra Balázs Dóra Cǎtǎlin Paşcu Moca Gergely Zarand

Publication Name: Scipost Physics Core

Publication Date: 2022-01-01

Volume: 5

Issue: 1

Page Range: Unknown

Description:

We study the dissipative dynamics of one-dimensional fermions, described in terms of the sine-Gordon model in its free massive boson or semi-classical limit, while keeping track of forward scattering processes. The system is prepared in the gapped ground state, and then coupled to environment through local currents within the Lindblad formalism. The heating dynamics of the system is followed using bosonization. The single particle density matrix exhibits correlations between the left and right moving particles. While the density matrix of right movers and left movers is translationally invariant, the left-right sector is not, corresponding to a translational symmetry breaking charge density wave state. Asymptotically, the single particle density matrix decays exponentially with exponent proportional to -γt|x|∆2 where γ and ∆ are the dissipative coupling and the gap, respectively. The charge density wave order parameter decays exponentially in time with an interaction independent decay rate. The second Rényi entropy grows linearly with time and is essentially insensitive to the presence of the gap.

Open Access: Yes

DOI: 10.21468/SciPostPhysCore.5.1.004

Comparison of Clustering-Based Virtual SEA Subsystem Generation Models

Dániel Feszty David Sipos

Publication Name: Journal of Theoretical and Computational Acoustics

Publication Date: 2023-09-01

Volume: 31

Issue: 3

Page Range: Unknown

Description:

Building a valid Statistical Energy Analysis (SEA) model is far from straightforward in real life applications because it has to comply with certain requirements. Since intuition-based SEA subsystems do not always entirely meet these, more advanced methods such as clustering techniques have been proposed for model building. This paper focuses on the comparison of different clustering techniques from SEA model validity point of view in the case of a simplified car body model. Besides the compliance with the SEA theory, each obtained model is compared to a reference finite element simulation to assess its accuracy.

Open Access: Yes

DOI: 10.1142/S2591728523500081

Maximizing battery life and usable capacity with battery management system in electric vehicles

Zoltán Szeli Gábor Szakállas Ferenc Szauter

Publication Name: Proceedings of the ASME Design Engineering Technical Conference

Publication Date: 2017-01-01

Volume: 9

Issue: Unknown

Page Range: Unknown

Description:

In terms of the electric vehicles is an important issue of sizing a battery pack. The designer must take account of parameters such as cost, weight and durability. We can optimize these parameters with the help of a battery management system with integrated active cell balancing function. The article describes the development of a battery management system that developed by the Research Centre of Vehicle Industry at Széchenyi István University, Gyor, Hungary.

Open Access: Yes

DOI: 10.1115/DETC2017-67939

Knowledge management strategy as a chance of small and medium-sized enterprises

Andrea Bencsik Tímea Juhász

Publication Name: Organizational Culture and Behavior Concepts Methodologies Tools and Applications

Publication Date: 2017-02-10

Volume: 2-4

Issue: Unknown

Page Range: 577-607

Description:

This chapter shows how SMEs can compete with multinational companies. This chapter was written on the basis of practical research results. In this research, Hungarian and Slovakian SMEs were investigated from the view of a knowledge-based economy. The question was how they can face future challenges. The researchers wanted to know how SMEs handle their chance which is hidden in their way of thinking about a knowledge strategy. As a result, these companies seem to be afraid, uncertain, and think their success is only luck or a current incident. They live a "fly by night" existence, and they do not feel the importance of development, of studying, of knowledge, they run after work and money. These enterprises feel that they have to survive, and to this, they need money and financial capital. Therefore, knowledge and studying fall behind.

Open Access: Yes

DOI: 10.4018/978-1-5225-1913-3.ch028

How cognitive infocommunications play a critical role in shaping the future of forensic sciences defining forensic cognitive infocommunications

Andras Czebe Gabor Kovacs

Publication Name: 7th IEEE International Conference on Cognitive Infocommunications Coginfocom 2016 Proceedings

Publication Date: 2017-01-03

Volume: Unknown

Issue: Unknown

Page Range: 283-287

Description:

Forensic sciences are facing radical changes. Cognitive technologies are one of the main efforts in forming these changes which can fulfill cognitive procedures that were once exclusively the scope of forensic experts. However, the acquisition of a cognitive structure that makes experts more effectual, can also lead them to erroneous identifications. Therefore, one must fully examine and interpret how information transfer occurs between two cognitive beings. Our focus in this paper is to lay the basis and to inspire further research on the development of Forensic Cognitive Infocommunications.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2016.7804562

MANAGING SOCIAL PROTECTION FOR EX-COMBATANTS: EVALUATING EFFECTIVENESS THROUGH КРІ METHODOLOGY

Yuriy Bilan Halyna Mishchuk Natalia Samoliuk Iryna Roshchyk

Publication Name: Polish Journal of Management Studies

Publication Date: 2025-06-25

Volume: 31

Issue: 1

Page Range: 248-263

Description:

The management of the ex-combatants’ social protection is analysed using the KPI methodology. For this analysis, five blocks of indicators are adapted: “input” – funding allocated to ex-combatants’ social protection; “output” – ex-combatants’ participation in social programs; “activity” – funding per recipient and final performance of social protection; “mechanism” – administrative efforts required to achieve the intended outcomes; “control” – effectiveness of ex-combatants’ social protection compared to other population groups. The methodology has been tested in Ukraine using a system of 28 indicators available in 2020-2023. The lowest efficiency is typical for input indicators, mainly support programs funding (0.153 in 2022), the highest values were observed for activities indicators (ranging from 0,609 to 0.871). However, the essential distance from maximum level of 1.0 is obvious for all indicators. This approach allows for identifying existing gaps and opportunities to improve public management of ex-combatants’ social protection.

Open Access: Yes

DOI: 10.17512/pjms.2025.31.1.14

Automated Multi-Dimensional Corrosion Growth Modeling Based on In-Line Inspections

Péter Földesi Mohamad Shatnawi

Publication Name: IEEE Access

Publication Date: 2026-01-01

Volume: 14

Issue: Unknown

Page Range: 57997-58015

Description:

Corrosion is responsible for up to one-third of reported pipeline incidents. Given the extensive length and limited accessibility of pipelines, operators rely on in-line inspections (ILIs) to detect and quantify corrosion defects. Although modern ILI tools provide detailed geometric descriptions of corrosion behavior, translating successive inspections into reliable growth models remains challenging. Measurement uncertainty, defect coalescence, and the joint evolution of length, width, and depth complicate learning consistent growth patterns. This study proposes a unified framework for automated corrosion growth modeling that integrates feature matching, feature engineering, and data-driven prediction into a single workflow. The framework targets defect-level modeling by jointly learning multi-dimensional corrosion growth of length, width, and depth, and by reducing correspondence-induced artifacts arising from defect coalescence and measurement uncertainty. The effectiveness of the framework was evaluated using three consecutive ultrasonic testing inspections of an API 5L X52 offshore water-injection pipeline segment. Extreme Gradient Boosting (XGBoost), a feed-forward neural network, Random Forest, and linear regression were used to assess the stability of the proposed geometric representation across learning paradigms. Integrity-oriented evaluation using Estimated Repair Factor (ERF) indicates that integrity-relevant trends are preserved. Furthermore, geometry-oriented evaluation using agreement and error analyses indicates strong performance for axial length and circumferential width, with modestly reduced performance for depth. Overall, the results suggest that the proposed framework provides a practical basis for defect-level automated corrosion growth modeling.

Open Access: Yes

DOI: 10.1109/ACCESS.2026.3683313

Effect of Geocell, on the Mechanical Behavior of Railway Embankments, Using FE Modeling

Morteza Esmaeili Guoqing Jing Guixian Liu Farshad Astaraki Majid Movahedi Rad Reza Esfandiari Mehni

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2022-01-01

Volume: 19

Issue: 6

Page Range: 63-80

Description:

In nature, the mechanical properties of soils, vary from region to region and in some areas, high-strength soil resources lack is a serious difficulty that geotechnical engineers may face where constructing earthworks such as railway and road embankments is required. Although a wide range of soil improvement techniques exists to improve such soils, the effect of geocell, as an effective solution, has not yet been investigated for railway embankments, hence, the present study aims to develop a three-dimensional (3D) Finite Element (FE) model, to fill the gap. To do this, first, six, 1/20 scaled-down railway embankments, including an unreinforced and 5 reinforced ones, were constructed in the lab and their load-settlement behavior, was assessed. Second, a 3D FE model was validated by experimental results and then, using a parametric study, the effect of geocell opening size and geocell layers number, were investigated on bearing capacity and settlement of the embankments, for five various types of soil ranging from poor soils (ST1), to high strength soils (ST5). The outcomes indicated, although adding geocell layers up to 15 layers, results in reducing the exerted stress in railway embankments by a maximum of near 50%, the crest settlement is not efficiently affected. Moreover, it was found that geocell’s opening size has a negligible effect on decreasing the embankment’s settlement, while it affects the bearing capacity significantly, up to a maximum of 50%.

Open Access: Yes

DOI: DOI not available

High prevalence of burnout among midwives in Hungary: High job demands and low resources as potential persistent stressors, a focus on prevention

Mihály Dió Ibolya Lipienné Krémer József Vitrai Szilvia Ádám Zsuzsanna Soósné Kiss

Publication Name: Heliyon

Publication Date: 2024-01-30

Volume: 10

Issue: 2

Page Range: Unknown

Description:

Background: Midwifery practice in Hungary is characterized by chronic stress, which may in turn lead to burnout and impaired perinatal care. However, little is known about the degree and potential stressors of burnout, which hinder the development of strategies to promote well-being among midwives in Hungary. Aim: To assess the prevalence of burnout and identify persistent individual and occupational stressors among midwives in Hungary over the past decade to inform prevention. Methods: We conducted two cross-sectional studies among midwives in 2014 and 2022. We used the Maslach Burnout Inventory to assess burnout (emotional exhaustion, depersonalization, and personal accomplishment) over time. We also collected data on individual and work characteristics. We performed a multivariate regression analysis to explore associations between burnout and respondents' characteristics. Findings: The degree and prevalence of emotional exhaustion among midwives increased significantly between 2014 (N = 224) and 2022 (N = 152). High workload, not feeling valued at work, poorly perceived health status and work dissatisfaction emerged as a significant positive correlate of emotional exhaustion or depersonalization in both studies. Living alone showed both a positive and inverse association with burnout in 2014 and 2022, respectively. Work satisfaction was a positive correlate of personal accomplishment in both studies. Conclusions: Our results add to and confirm the growing body of evidence about the high prevalence of burnout among midwives in Hungary. We identified potential risk factors and outcomes of burnout, which remained unchanged over time. To prevent or reduce burnout among midwives, future interventions should focus on addressing these potential persistent risk factors. However, the time-varying role of factors influencing burnout makes it advisable to review preventive interventions from time to time.

Open Access: Yes

DOI: 10.1016/j.heliyon.2024.e24495