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Found 6289 publications

Overview of Hungarian operations research based on the VOCAL 2022 conference

Botond Bertok Marianna E.-Nagy Péter Biró

Publication Name: Central European Journal of Operations Research

Publication Date: 2024-12-01

Volume: 32

Issue: 4

Page Range: 897-902

Description:

The latest results of the Hungarian operations research community is reviewed based on the presentations given at the VOCAL 2022 conference. International collaborations and the continuation of research published at previous conferences of the series are also summarized.

Open Access: Yes

DOI: 10.1007/s10100-024-00930-3

Feedback Linearization Based Induction Machine Control

Miklós Kuczmann

Publication Name: Gpmc 2020 2nd IEEE International Conference on Gridding and Polytope Based Modeling and Control Proceedings

Publication Date: 2020-11-19

Volume: Unknown

Issue: Unknown

Page Range: 9-12

Description:

The paper presents the feedback linearization based control of induction machines, both the speed control and the torque control. The nonlinear state space model is decoupled into two linear subsystems, and these systems have been stabilized independently by the pole placement technique, finally speed and torque control have been realized by integral control. The block diagram is presented, and some tests have been performed to show the control system behavior.

Open Access: Yes

DOI: 10.1109/GPMC50267.2020.9333810

The impact of socio-economic factors on the dynamics of social pressure in Kazakhstan

Laszlo Vasa Assel Bekbossinova Meiirzhan Abdykadyr Sabden Orazaly

Publication Name: Problems and Perspectives in Management

Publication Date: 2025-01-01

Volume: 23

Issue: 4

Page Range: 61-74

Description:

The purpose of the study was is to assess the impact of key factors (including employment, income, poverty level, prices and social support) on the dynamics of social pressure in Kazakhstan. The analysis covered the period from 2014 to 2024 and utilized official data. The methodology combines entropy-based ranking of indicators, calculation of the Socio-Economic Pressure Index (SEPI), Social Stability Index (SSI), and Social Inertia Index (SII), as well as phase-portrait visualization. The entropy ranking revealed that the share of population below the food basket cost (di = 0.71; Wi = 0.2381) and housing assistance (di = 0.516; Wi = 0.1728) had the highest variability and the strongest influence on SEPI. Moreover, SEPI rose from 0.0967 in 2014 to its peak in 2023 – over 20 times higher – before falling to 0.53 in 2024. SSI dropped from 4.94 in 2017 to 0.44 in 2023, with minimal adaptive capacity, and partial recovery to 1.87 in 2024. There was recorded instability of positive changes and a high likelihood of renewed pressure due to the lowest value of SII (–3.24) in 2024. Thus, long-term stability and a reduction in the social sphere’s susceptibility to external and internal shocks require integrated policy measures that combine targeted support, income regulation, and adaptive governance.

Open Access: Yes

DOI: 10.21511/ppm.23(4).2025.05

Interpolative decisions in the fuzzy signature based image classification for liver CT

Ferenc Lilik Melinda Kovacs Szonja Krisztina Szujo László T. Kóczy Szilvia Nagy

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2021-07-11

Volume: 2021-July

Issue: Unknown

Page Range: Unknown

Description:

In computer aided diagnostics image processing and classification plays an essential role. Image processing experts have been developing solutions for different types of problems, that can be related to image processing, however, due to the sensitivity of the data and the high cost of medical experts, these experimental methods usually have very limited use in real medical practice. The databases that are available are very limited, thus the elsewhere usual and extremely effective convolutional neural network or other automated learning methods are not so easy to adjust for medical image processing. To overcome this difficulty, this paper presents an expert knowledge based method which describes the decision structures by fuzzy signatures. Values of various properties of Computer Tomography images as e.g. density or homogeneity are being considered in these signatures that are different in all case of liver diseases. Because of the low number of samples available, fuzzy sets that describes the leafs of the signatures leads to sparse systems, hence interpolation is needed. However further investigations of other interpolation methods are planned, Stabilized Koczy-Hirota interpolation seems to be appropriate.

Open Access: Yes

DOI: 10.1109/FUZZ45933.2021.9494401

A Grid-Based Model for Parameter Initialization in Non-Convex Optimization Tasks

Adam B. Csapo

Publication Name: Gpmc 2019 1st IEEE International Conference on Gridding and Polytope Based Modeling and Control Proceedings

Publication Date: 2019-11-01

Volume: Unknown

Issue: Unknown

Page Range: 19-23

Description:

The role of nature versus nurture, and the relative strengths and weaknesses of evolutionary and gradient-based approaches have been the subject of fiery debate in the AI community for quite some time. As outlined in the paper, these approaches have unique advantages and at the same time by no means exhaust the list of tools necessary for designing artificially intelligent behavior. In particular, the importance of parameter initialization is often underestimated, as demonstrated by the widely publicized 'lottery ticket hypothesis'. Following a discussion on why parameter initialization seems to be more important than previously acknowledged, a grid-based model is introduced which combines certain characteristics of evolutionary and gradient-based approaches with the goal of supporting robust parameter initialization.

Open Access: Yes

DOI: 10.1109/GPMC48183.2019.9106960

Bioactive Potential of Actinobacteria Strains Isolated from the Rhizosphere of Lavender, Lemon Balm, and Oregano

Balázs Ásványi E. Lakatos Babett Greff András Sáhó Viktor Karikás László Varga

Publication Name: Agriculture Switzerland

Publication Date: 2024-10-01

Volume: 14

Issue: 10

Page Range: Unknown

Description:

The objective of this study was to isolate and characterize actinobacteria from the rhizosphere of medicinal and aromatic plants, specifically lavender (Lavandula angustifolia Mill.), lemon balm (Melissa officinalis L.), and oregano (Origanum vulgare L.). Rhizospheric soil samples revealed a high abundance of culturable actinobacteria (6.97–7.23 log10 CFU/g). Six isolates were selected for their promising enzymatic activities (lignin peroxidase, carboxymethyl cellulase) and antimicrobial properties. Isolates M345 and M162 exhibited the highest cellulase activity indices (3.19 ± 0.71 and 2.54 ± 0.22, respectively), with five isolates producing lignin peroxidase. These actinobacteria also demonstrated plant growth-promoting traits such as phosphate solubilization and nitrogen fixation, along with strong antimicrobial activity against Gram-negative bacteria and phytopathogenic fungi. Additionally, they significantly enhanced maize seed germination, increasing the vigor index from 4283.33 ± 1264.37 to 6248.28 ± 1661.94 compared to that of the control. These results indicate that the isolated actinobacteria strains hold potential as microbial inoculants for sustainable agriculture, contributing to soil health, plant growth, and pathogen management.

Open Access: Yes

DOI: 10.3390/agriculture14101758

Europeanization of the Hungarian legal order: From convergence to cancellation?

Balázs Horváthy Tamas Dezso Ziegler

Publication Name: Law in Eastern Europe

Publication Date: 2018-01-01

Volume: 67

Issue: Unknown

Page Range: 24-40

Description:

Since the political transition of Hungary in the late 1980s, the law of the European Union has been the primary external influence on the modernization of domestic legislation. This chapter aims to illustrate that Hungary, as a passive and receptive actor, implemented all components of eu law which were prerequisites for eu membership. This has resulted in an intense convergence in rules and values of the domestic and eu legal order until its accession to the eu in 2004. After accession, however, Hungary started to move from a constructive to confrontational Member State, which has led to a substantial divergence between the laws of Hungary and eu law. This chapter analyzes these processes and attempts to identify the possible consequences of this alteration in the Hungarian stance to the adoption of rules, values, and regulatory models originating from eu law. It will be demonstrated with case studies ranging from recent Hungarian economic legislation to the constitutional reform, illustrating how this new role of Hungary negatively affects the adaptability of Hungarian legal order and leads to canceling the convergence to the European law.

Open Access: Yes

DOI: 10.1163/9789004352070_004

Review and conceptual design of FPGA-based application for data-driven power electronic systems

Adrienn Dineva Adam Zsuga

Publication Name: 2021 17th Conference on Electrical Machines Drives and Power Systems Elma 2021 Proceedings

Publication Date: 2021-07-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

AI-based data-driven methods are an emerging research direction in the field of power electronics. However, because of the absence of large datasets, the development of these solutions have some barriers to overcome. To properly train machine learning algorithms and neural networks a large amount of training data is necessary. This dataset can be a union of simulation and measured data. Generating simulation data with computer simulations can be slow process and gathering real data is not cost-effective. Real-Time simulators based on FPGAs can be powerful tools to accelerate simulation, and create datasets for AI applications in a cost-effective and accurate way. In this paper the possible FPGA-based solutions, which can be applicable for the problems, have been reviewed. Their applicability have been discussed, moreover a simplified FPGA-based concept have been designed and embedded into two possible AI-based application area.

Open Access: Yes

DOI: 10.1109/ELMA52514.2021.9503033

Exercise addiction: A review and evaluation of current research and theory

Zsolt Demetrovics Bhavya Chhabra Mark D. Griffiths Attila Szabo

Publication Name: Journal of Behavioral Addictions

Publication Date: 2026-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Background and Aims: While regular physical activity provides many health benefits, exercise can cause more harm than good when done excessively to the point where a person loses control. This condition has been called various names, but the most accurate term is ‘exercise addiction’ (EA) because it reflects both compulsive behavior and dependence. EA is classified as a non-substance-related addictive disorder, or behavioral addiction, and has been the subject of research for over fifty years. However, it is not officially recognized in major diagnostic systems, mainly due to significant conceptual and measurement challenges. This paper provides an overview of current knowledge on EA, including its causes, assessment issues, epidemiology, associated conditions, negative effects, and options for treatment and prevention. Methods: An evaluation-driven narrative review was conducted which synthesized findings from empirical research and theoretical models adopted across EA research. It critically examined prevailing conceptualizations, methodological challenges, and potential treatment approaches. Results: Epidemiological findings are inconsistent and report inflated prevalence rates, partly due to reliance on self-report instruments that often fail to distinguish pathological exercise from passion. Etiological models emphasize the complex interplay between biological, psychological, and behavioral factors. Negative consequences include physical injury, emotional distress, and social strain. Evidence for effective interventions remains sparse. Discussion and Conclusions: Despite growing interest, progress remains slow. There is a need for larger, longitudinal, and experimental studies to advance understanding. Though not included in the DSM-5, greater clinical awareness is vital for early detection and prevention. EA is clinically relevant but still poorly defined, requiring robust empirical and theoretical work.

Open Access: Yes

DOI: 10.1556/2006.2025.00336