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Found 6515 publications

Learning-aided observer design for improving autonomous vehicle safety

Balazs Nemeth Andras Mihaly Peter Gaspar Mihály Kopasz Ferenc Szauter

Publication Name: Scientific Reports

Publication Date: 2026-12-01

Volume: 16

Issue: 1

Page Range: Unknown

Description:

This paper introduces a novel method for the enhancement of automated vehicle safety and efficiency during critical manoeuvres. The fundamental of the presented method is the observer design architecture, in which lateral dynamic states of the vehicle are evaluated. The novel observer consists of both model-based and machine-learning-based methods to ensure the selected design performances, such as efficient trajectory tracking and safety evaluation of the autonomous vehicle. In contrast to the already introduced and applied stability index-based methods, the proposed safety evaluation process is able detect stability loss and performance degradation of the autonomous vehicle. In the proposed observer-based safety evaluation method, stability and performance loss detection is based on the comparison of model-based and learning-based state observation. The main novelty of the paper is the design of the reinforcement learning (RL) based observer in a guaranteed structure that results in small observation error even under nonlinear vehicle dynamics. Furthermore, a lateral safety index is defined based on the value of the improvement vector representing the addition to the model-based estimation. By this means, with the proposed safety evaluation method both safety and performance loss hazards can be identified simultaneously.

Open Access: Yes

DOI: 10.1038/s41598-026-35378-9

What Does Hide the Basket of West-Hungarians? – An Analysis of the Basket Composition of Different Households in West Hungary

Boglárka Eisingerné Balassa Tímea Vastag Boglárka Eisinger-Balassa

Publication Name: International Scientific Business Conference Limen Leadership Innovation Management and Economics Integrated Politics of Research

Publication Date: 2024-01-01

Volume: 2024

Issue: Unknown

Page Range: 519-526

Description:

The economic changes of recent years have had a significant impact on household consumer behavior. Following the changes caused by the COVID-19 epidemic, consumers had to face high inflation. These macro-level changes significantly impacted households and made budget planning difficult. This study aims to prepare and validate the methodology aimed at the composition and sustainability analysis of consumer baskets in different regions of Hungary. As a pilot study, the Reference Budget is determined based on focus group discussions with family types specified by the statistical office of the Western Hungary region, which represents the threshold value that households need for subsistence. Using the Hypothetical Household Tool (HhoT), this value compares the after-tax income for each type of household and analyses whether there is overspending in the examined cases. After that, based on the research participants’ answers, sustainability calculations are performed based on the consumer basket’s composition, thus validating that overspending is not sustainable.

Open Access: Yes

DOI: 10.31410/LIMEN.2024.519

Construction of two-sided bounds for initial-boundary value problems

C. Grossmann Zoltán Horváth

Publication Name: Applied Numerical Mathematics

Publication Date: 2002-08-01

Volume: 42

Issue: 1-3

Page Range: 177-187

Description:

The present paper extends the bounding operator approach developed for boundary value problems to the case of initial-boundary value problems (IBVPs). Following the general principle of bounding operators enclosing methods for the case of partial differential equations are discussed. In particular, continuous discretization methods with an appropriate error bound controlled shift and monotone extensions of Rothe's method for parabolic problems are investigated. © 2001 IMACS. Published by Elsevier Science B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/S0168-9274(01)00149-0

Application of tensor product models for vehicle de-formational processes

Istvan Harmati András Rövid Péter Várlaki

Publication Name: Proceedings of the Mini Conference on Vehicle System Dynamics Identification and Anomalies

Publication Date: 2006-12-01

Volume: Unknown

Issue: Unknown

Page Range: 615-620

Description:

Modelling of vehicle deformational processes plays an important role in car body design and accident analysis. It is a difficult task and usually carried out applying a kind of finite element method. Determination of the absorbed energy by the deformation and the corresponding energy equivalent speed (EES) can be of great importance. Exact determination or measuring of these quantities is almost impossible, so one could estimate them. In this paper we introduce a modeling technique and a model for describing the deformation process. A short description of the main idea: let we have a 3-dimensional rectangular grid on the vehicle body (or on something else). The partition is determined by taking into consideration the energy absorbing properties of the parts of the vehicle, so each cell is approximately homogenous. The cells could be identified as the entries of a tensor of order 3. We concentrate on the energy absorbed by the cells, but not on the physical coordinates of the cells. Energy absorption property (rate of the input and the absorbed energy) of a certain cell could change during the deformational process, so the absorbed energy is calculated using a monotonous decreasing function. These functions can be defined for each possible orthogonal direction of the possible impact. Instead of the original impact we deal with its orthogonal components and the result will be the sum of the particular results. The rectangular grid allows us to compute from level to level. These computations can be realized applying tensor products, the model has low complexity which can be more decreased by complexity reducing methods known from linear algebra.

Open Access: Yes

DOI: DOI not available

Regional statistics in confined two-dimensional decaying turbulence

Gábor Tóth Gábor Házi

Publication Name: Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering Sciences

Publication Date: 2011-06-28

Volume: 369

Issue: 1945

Page Range: 2555-2564

Description:

Two-dimensional decaying turbulence in a square container has been simulated using the lattice Boltzmann method. The probability density function (PDF) of the vorticity and the particle distribution functions have been determined at various regions of the domain. It is shown that, after the initial stage of decay, the regional area averaged enstrophy fluctuates strongly around a mean value in time. The ratio of the regional mean and the overall enstrophies increases monotonously with increasing distance from the wall. This function shows a similar shape to the axial mean velocity profile of turbulent channel flows. The PDF of the vorticity peaks at zero and is nearly symmetric considering the statistics in the overall domain. Approaching the wall, the PDFs become skewed owing to the boundary layer. © 2011 The Royal Society.

Open Access: Yes

DOI: 10.1098/rsta.2011.0070

Sequential model predictive direct speed control of PMSM

Karol Kyslan Krisztian Horvath Lukáš Pancurák Krisztián Horváth

Publication Name: Scientific Reports

Publication Date: 2026-12-01

Volume: 16

Issue: 1

Page Range: Unknown

Description:

Finite control set model predictive control (FCS-MPC) has emerged as a powerful strategy for permanent magnet synchronous motor (PMSM) drives. However, its performance strongly depends on appropriately chosen weighting factors, which directly affect control quality and, in some cases, may even lead to instability. Despite the crucial role of weighting factors, there is no systematic or generally accepted procedure for selecting their values, which limits the robustness and practical applicability of conventional FCS-MPC methods. To overcome this limitation, this paper presents the experimental validation of a sequential direct speed predictive control strategy for PMSM. The individual cost functions are evaluated sequentially, thereby tuning is simplified and weighting factors are reduced. Experimental results show that the original version of sequential direct speed control, as proposed in the literature, exhibits promising dynamic performance but suffers from instability and current ripples under certain conditions. To address these issues, an enhanced version of the sequential direct speed predictive control is proposed in the paper. It effectively suppresses instabilities and enhances the speed dynamic response of the drive. The proposed approach was experimentally validated using the OP 5600 rapid control prototyping platform running RT-LAB software and a 1.1 kW PMSM machine.

Open Access: Yes

DOI: 10.1038/s41598-026-39256-2

Seismic Performance and Sustainability of Reinforced Concrete Buildings: a Comprehensive Assessment

Nurullah Bektaş Samuel Alexandro Silitonga

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 781-786

Description:

Recent earthquakes such as the 2023 Türkiye-Syria, Morocco, and Afghanistan, 2015 Gorkha Nepal, and 2009 Indonesia earthquakes have demonstrated the vulnerability of existing building stock. Throughout Europe, many existing buildings were constructed considering low or moderate standards or without considering them. This study investigates the seismic performance of reinforced concrete (RC) buildings, exemplified as a six-story RC dormitory building, focusing on various support and foundation conditions, soil characteristics, and site seismicity scenarios representing the seismicity of Europe. The research aims to assess the potential effects of exceeding anticipated site seismic intensities, potentially leading to safer communities and infrastructure in the face of impending earthquakes. Robot Structural Analysis Professional software is used for structural analysis and design throughout soil-structure interactions and site seismicity considerations. Moreover, this study investigates the environmental implications of RC buildings, which represent the future building inventory in Europe. It examines the varying material usage required to design structures compliant with Eurocode standards through a life cycle analysis. The methodology employed in this investigation aligns with the core principles of practical design encompassing economic and environmental sustainability. The study's key findings indicate that increasing member size can enhance performance at lower intensities, but this may not be a sufficient strategy at higher intensities, where shear walls may be necessary in high seismic zones. Sustainable design necessitates a balance between material use, performance, and environmental impact.

Open Access: Yes

DOI: 10.3303/CET24114131

Vector Preisach hysteresis modeling: Measurement, identification and application

Miklós Kuczmann

Publication Name: Physica B Condensed Matter

Publication Date: 2011-04-01

Volume: 406

Issue: 8

Page Range: 1403-1409

Description:

The paper presents a Preisach model to simulate the vector hysteresis properties of ferromagnetic materials. The vector behavior has been studied using a single sheet tester with a disk-shaped specimen at low frequency. The locus of the magnetic flux density vector has been controlled by a digital measurement system. An inverse vector Preisach hysteresis model has been developed and identified by applying the measured data. Finally, the inverse model has been inserted into a finite element procedure through the fixed point technique and the reduced magnetic scalar potential formulation to simulate the measurement system. The applicability of the measurement system as well as the developed model has been proven by comparing measured and simulated results. © 2011 Elsevier B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/j.physb.2011.01.037

Colistin residues and colistin-resistant Enterobacteriaceae in agricultural soils: Sources, risks, and remediation strategies

E. Lakatos Babett Greff Miklós Posgay L. Varga

Publication Name: Environmental Research

Publication Date: 2026-03-01

Volume: 294

Issue: Unknown

Page Range: Unknown

Description:

Polymyxins, including colistin, are critical last-line antibiotics, and their environmental dissemination raises One Health concerns. This review synthesizes current evidence on the occurrence, sources, environmental fate, and mitigation of colistin residues and colistin-resistant Enterobacteriaceae in agricultural soils, with emphasis on transmission pathways to crops and implications for food safety along the farm-to-fork continuum. Principal inputs from livestock manure, reclaimed wastewater, and wildlife are characterized. Resistance mechanisms, with a focus on plasmid-mediated mobile colistin resistance (mcr), are summarized. Although animal manure may be a significant source of colistin due to its low gastrointestinal absorption, soil concentrations are low, with bioavailability influenced by physicochemical parameters, including pH, clay content, cation exchange capacity, and organic matter content. Low desorption rates limit plant uptake; thus, the primary environmental risk arises from the selection and enrichment of colistin-resistant bacteria and mcr genes in the rhizosphere, as well as splash-mediated deposition of contaminated particles. In farm and arable soils, mcr-1 and mcr-3 have been identified as the dominant variants, with higher prevalence in livestock-associated environments. Their dissemination is primarily driven by horizontal gene transfer rather than clonal expansion, influenced by factors such as soil characteristics, heavy metals, soil treatments, and plant root exudates. Interventions are critically appraised, spanning veterinary stewardship and on-farm hygiene, physical processes, chemical approaches, and biological strategies, along with postharvest barriers that include Good Agricultural Practices and Hazard Analysis and Critical Control Points, washing and sanitization, and bacteriophage biocontrol. Major conclusions are that multi-barrier, context-specific programs can reduce environmental selective pressures and interrupt gene flow while maintaining agronomic viability, yet progress remains constrained by gaps in standardized surveillance (particularly for plant-based foods), and by the limited use of quantitative risk assessment and field-scale validation of remediation technologies. A One Health framework that integrates environmental monitoring with public-health endpoints is needed to guide proportionate policy and practice.

Open Access: Yes

DOI: 10.1016/j.envres.2026.123771