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Found 6278 publications

Timing Chain Wear Investigation Methods – Review

Cs Tóth-Nagy J. Rohde-Brandenburger L. Paulovics

Publication Name: Fme Transactions

Publication Date: 2022-01-01

Volume: 50

Issue: 3

Page Range: 461-472

Description:

Several methods are used for investigating timing chain wear, from fired engine dynamometer tests through tribological model tests to simulations. Research over the past decade has shown that component or tribometer tests can replace expensive engine dynamometer tests in many cases. Simulation methods can further reduce the cost and time of development. Simulation models require experimentally defined input parameters; therefore, experiment-based methods cannot be completely avoided. However, a comprehensive comparison or validation of the various experimental and simulation techniques is difficult, as the literature on the topic is relatively scarce. This study aims to give a systematic comparison of the results of several investigation methods of timing chain wear, supported by data measured at Széchenyi István University, such as fired engine dynamometer tests, cold dynamometer tests, component tests, and tribometer tests, presenting their benefits and limitations, where possible through examples and results. The study also provides an insight into the compatibility of different measurement methods.

Open Access: Yes

DOI: 10.5937/fme2203461P

Metaheuristics in Hierarchical Nested Structure

Boldizsar Tuu-Szabo Ali Jawad Ibada László T. Kóczy

Publication Name: Cinti 2025 IEEE 25th International Symposium on Computational Intelligence and Informatics Proceedings

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 547-550

Description:

Metaheuristic algorithms have become indispensable tools for solving complex combinatorial optimization problems. However, their performance often depends critically on the selection of internal parameters, which are frequently tuned in an ad hoc manner. This paper investigates the hierarchical nested structure of the metaheuristic algorithm and its impact on optimization performance, where parameters of one metaheuristic are optimized using another, resulting in a multi-level optimization framework. We demonstrate this concept using a four-tier architecture: the Genetic Algorithm (GA) optimizes the Radius (R) parameter in the Circle Group Heuristic (CGH), which in turn constructs high-quality initial populations for the Discrete Bacterial Memetic Evolutionary Algorithm (DBMEA). The DBMEA itself is a memetic algorithm that integrates global evolutionary mechanisms from Bacterial Evolutionary Algorithm (BEA) and with local search strategies (2-OPT and 3- OPT), thus comprising two inherent levels. Together, this nesting creates a four-level metaheuristic hierarchy. The DBMEA is then applied to solve variants of NP-Hard problems such as Traveling Salesman Problem (TSP). Our experiments on benchmark datasets show that this nested structure not only improves convergence speed and solution quality but also demonstrates the potential of deeply nested metaheuristic designs for scalable, robust optimization.

Open Access: Yes

DOI: 10.1109/CINTI67731.2025.11311852

Digital Twin of Drone-based Protection of Agricultural Areas

Áron Ballagi Csaba Hajdu A. J. Kovács János Hollósi Gergely Teschner Norbert Boros

Publication Name: 2022 IEEE 1st International Conference on Internet of Digital Reality Iod 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 99-104

Description:

Protecting agricultural fields, like crops, vineyards, and husbandry areas, has been a difficult challenge since historical times. Classical methods to prevent intrusion are often destructive to wild and domestic animals alike. Even more current nondestructive systems, like camera-based systems are attributed to specific problems related to environmental or technological issues. Furthermore, verifying the effectiveness of installed systems is difficult, as the triggering situations are unmanageable and typically occur unsupervised. This paper presents a complex vision-based intrusion detection system to overcome these problems and further proposes more extensive control and flexibility on the development process. The solution provides a workflow integrating Digital Reality methods into the system development by creating a digital twin of the drone and its surrounding environment in a general-purpose robotic simulator. With this simulation, the triggering events and environmental effects can be easily emulated, such as a wild animal entering the area of interest. The solution also focuses on incorporating new 5G info-communication networks on handling communication between the intrusion detection system and the base station in a distributed manner.

Open Access: Yes

DOI: 10.1109/IoD55468.2022.9986763

MEASURING AGE-DEPENDENCE OF COLOUR AFTERIMAGE PERCEPTION

Lorinc Garai András Horváth

Publication Name: Light and Engineering

Publication Date: 2022-01-01

Volume: 30

Issue: 2

Page Range: 70-81

Description:

Afterimages are common and frequent perceptual phenomena of everyday life. A typical appearance is the negative “ghost” image of a bright light source when we turn away from it. In the case of significant colour contrast, the afterimage can be coloured. The perceived false image’s strength decreases gradually and completely disappears in a (10–100) s timescale. The underlying processes have multiple components: a quick adaptation on the retinal level, and a slower adaptation on the neural level. Several studies discuss these mechanisms, but there are still important questions to be answered. In our research, we apply the top-level, black-box style approach: instead of focusing on the inner details, we ask human test subjects to test and measure the duration and “strength score” of the same light-transitions. Our goal is to find the main features that affect the duration and subjective strength of the colour afterimages. Specifically, we examine whether the age and gender of the test subjects or the colourimetry parameters affect these parameters. Two set of experiments were performed: colour-colour transitions with 41 and colour-grey transitions with 16 test subjects between 19 and 62. We found that gender has no measurable influence, but age makes a difference in high significance. Both experiment types confirmed that over 40 years the average duration of colour afterimages decreases.

Open Access: Yes

DOI: 10.33383/2021-061

HyMeKo Language: Describing Complex Hypergraph-Like Data

None Csapó Csaba Hajdu

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2026-01-01

Volume: 23

Issue: 5

Page Range: 227-246

Description:

Numerous applications of computer science — including artificial intelligence, robotics, and cyber-physical systems — rely on highly connected data structures. Such complex information is most naturally and compactly described using a hypergraph-based approach, which enables concise representation of many-to-many relationships. In this paper, we introduce HyMeKo, a formal markup language designed to represent highly connected data based on hypergraph theory. Unlike traditional formats such as XML or JSON, HyMeKo offers a significantly more concise and semantically expressive way to model complex relationships by organizing data into a hypertree-based structure. The language supports template-based modeling and inheritance, enabling reusable, modular, and scalable data descriptions. HyMeKo is implemented as an LALR(1)-compliant language, allowing efficient parsing and transformation of structured data into hypergraphs. We provide a formal definition of the language, its supported operations, and relational rules, along with a comparative analysis demonstrating its syntactic efficiency. Application examples include robotic system descriptions, neural network architectures, and structured LLM prompts. We further present a structural complexity analysis showing that HyMeKo achieves a (k+1)-fold reduction in representational overhead compared to RDF reification for k-ary relationships, and provide an explicit comparison with RDF, OWL, and GraphQL. Reference implementations exist in both Python (PyLark) and Rust (LALRPOP).

Open Access: Yes

DOI: DOI not available

Enhancing sustainable performance through green human resource management: Green competencies building and green passion playing as a joint moderation

Selim Ahmed Abdullah Al Masud Mohammad Fakhrul Islam Nusrat Sharmin Lipy Md Kazi Hafizur Rahman Md Emon Anika Tasnim Mim

Publication Name: Acta Psychologica

Publication Date: 2025-10-01

Volume: 260

Issue: Unknown

Page Range: Unknown

Description:

This study aims to investigate the moderating effect of green competencies building (GCB) and green passion (GP) on the relationship between green human resource management (GHRM) and sustainable performance (SP). Moreover, it aims to find out the joint moderating effect of GCB and GP on the relationship between GHRM and SP. An online survey was used to gather 410 samples from various manufacturing organizations in Bangladesh, and the data was analyzed using structural equation modeling (SEM). The study found that GCB and GP separately and jointly moderate the relationship between GHRM and SP. This study uniquely explores how green competencies and green passion, both individually and jointly, moderate the relationship between GHRM and sustainable performance.

Open Access: Yes

DOI: 10.1016/j.actpsy.2025.105701

Presenting Climate-related Disclosures in the Automotive Sector: Practical Possibilities and Limitations of Current Reporting Prototypes and Methods

Árpád Tóth Alex Suta Katalin Borbély

Publication Name: Chemical Engineering Transactions

Publication Date: 2022-01-01

Volume: 94

Issue: Unknown

Page Range: 379-384

Description:

The eXtensible Business Reporting Language (XBRL) digital reporting system presents the annual accounts and financial data in a standardized format, thus producing comparable reports. This study examines how new sustainability reporting requirements proposed by the recent International Financial Reporting Standard (IFRS) S2 exposure draft could affect current reporting conditions of public listed European automotive manufacturers, from a taxonomical perspective. It was attempted the IFRS taxonomy to be linked with the ISSB's (International Sustainability Standards Board) proposed factors. Based on the changes in the regulatory environment and the existing digital reporting methodology, the paper proposed the inclusion of climate-related disclosure of automotive companies in the existing IFRS Taxonomy. In the taxonomical assessment, it was found that the recent sustainability reporting prototypes will likely affect certain financial statement sections, mostly the Notes to the financial statements. At present, there is no direct information available to investors and consumers on the environmental performance, which could be verified in the financial statements. There is no detailed emissions data that the company produces, as it is mainly the emissions compliance of the final product that is declared, especially in the automotive industry.

Open Access: Yes

DOI: 10.3303/CET2294063

A Mobile Robot and Vehicle Occupancy Map Construction Model

Claudiu Pozna Áron Ballagi Ernö Horváth

Publication Name: Ines 2019 IEEE 23rd International Conference on Intelligent Engineering Systems Proceedings

Publication Date: 2019-04-01

Volume: Unknown

Issue: Unknown

Page Range: 59-64

Description:

Occupancy gird map is a popular way of representing the environment regarding robots and vehicles. It consists of discrete cells, where each occupancy grid cell is valued independently. Because the represented grid structure is rigid it requires priori known memory resource concerning the size of the environment to obtain. Since their introduction, occupancy grid maps are still researched intensively [1] [2] [3]. In the current paper we propose the mathematical description of the computational simplification via alternative methods for occupancy map.

Open Access: Yes

DOI: 10.1109/INES46365.2019.9109531

A numerical method for creating and reconstructing computer-generated holograms

Lotfi Abdelhakim

Publication Name: Aip Conference Proceedings

Publication Date: 2012-12-01

Volume: 1479

Issue: 1

Page Range: 2182-2186

Description:

The main purpose of this article is to develop a program package which generates artificial holograms by numerical methods and these computer generated holograms are numerically reconstructed. For the calculation of light propagation needed in the generation of holograms or in the reconstruction of the object from the hologram, we use two strategies. The first is the Fourier-based algorithm where the diffraction integral is approximated as a convolution integral, allowing computation using the fast Fourier transform algorithm. The second uses finite difference discretization to solve the parabolic wave equation. Numerical tests that assess the accuracy of these algorithms are presented. © 2012 American Institute of Physics.

Open Access: Yes

DOI: 10.1063/1.4756625