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Found 6334 publications

Lateral-torsional buckling behaviour of I-beams with sinusoidally corrugated web

G. Hajdú Imre Cserpes Hartmut Pasternak

Publication Name: Bauingenieur

Publication Date: 2024-01-01

Volume: 99

Issue: 3

Page Range: 69-77

Description:

AB ST R AC T This paper presents a new approach to calculate the elastic lateral-torsional buckling moment of I-beams with sinusoidally corrugated webs. The appropriate hand calculation methods to determine the elastic critical moment of corrugated web beams have so far been based on the modification of the warping constant of the cross-section. Instead of modifying the warping constant, the corrugated web is modelled as a thin, equivalent orthotropic plate with uniform thickness. With the usage of the elastic critical moment the inelastic lateral-torsional buckling resistance of sinusoidally corrugated I-beam is determined according to the current Eurocode 1993–1–1:2005.

Open Access: Yes

DOI: 10.37544/0005-6650-2024-03-29

Learning Nonlinear Models of Dynamic Systems

Zoltán Szabó József Bokor

Publication Name: Sisy 2024 IEEE 22nd International Symposium on Intelligent Systems and Informatics Proceedings

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 11-15

Description:

Modeling dynamic systems is an important part in analysing and control of various systems arising either in health sciences or in the engineering word. Recent approaches to learn models from data are the so-called kernel-based methods and SVMs. There are strong relations to the theory of reproducing kernel Hilbert space (RKHS), to principal component analysis and canonic correlation analysis known previously from statistics. In recent form their use was extended from statistics to obtain models for dynamic systems. First we summarise the basics for the reproducing kernel based Hilbert space (RKHS) and the support vector machine (SVM) approaches. Following this it will be shown how some frequently used nonlinear models can be obtained by using these concepts. In the last part we discuss the structure estimation problem, i.e. how to determine the (least) number of features (observables) to describe the nonlinear system with a sparse representation.

Open Access: Yes

DOI: 10.1109/SISY62279.2024.10737570

Conservative Method for the Calculation of Thermal Forces in Reinforced Concrete Tunnel Wall During Fire

Éva Lublóy Zoltán Major János Szép

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 455-463

Description:

This article builds on the author's existing knowledge of the heating of reinforced concrete tunnel linings and deals with the structural analysis of tunnel linings under fire exposure. Due to space constraints, the issue of designing for earth pressure and surface loads is not address. Since the analysis of thermal stresses due to restrained deformations is insufficient in the available literature, we complement the existing theoretical knowledge with the knowledge provided by the relevant standards for reinforced concrete tunnel linings. In addition, we add our own individual reflections to the theory where we have identified gaps. In determining the additional stresses due to inhibited thermal expansion, we use a numerical model based on our own ideas. The reason for this is that the heating of reinforced concrete tunnel lining during fire is extremely uneven and it is almost impossible to take this into account in the finite element programs commonly used. The other important reason is that this uneven temperature change that causes the colder zones of the wall to inhibit deformation. Thus, a solution implemented in MS Excel environment is presented, which allows an approximate accurate determination of the force effects due to inhibited deformation. The solution used and the values proposed are based on the authors' individual ideas and are not the result of an accepted professional consensus. In all cases where more precise data are required, it is recommended that a more accurate test be carried out. Advanced finite element modelling can provide the necessary support for designers and experts.

Open Access: Yes

DOI: 10.3233/ATDE240579

Analysis of Potential Energy Transition Schemes in Hungary: from Natural Gas to Electricity

László Palkovics Csaba Gondola Tibor Gulyás László Palkovics

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 871-876

Description:

Hungary, as a landlocked nation with limited raw material resources, faces significant challenges in ensuring a stable energy supply, necessitating extensive interconnectors with neighbouring countries for gas, oil, and electricity. While progress has been made, especially in electricity interconnections, the Russian-Ukrainian conflict and the EU’s decarbonisation goals for 2050 introduce new pressures on energy security. Hungary's energy trilemma—balancing access and affordability, environmental targets, and security—guides its strategy as it seeks an optimal energy mix. By 2050, energy demand is projected to hold steady at 210 TWh, though the current 65 % fossil fuel share, largely imported, highlights Hungary’s vulnerabilities (exposure to risks and insecurities in its energy supply). Goals include net-zero emissions, reduced foreign dependency, and manageable energy costs, with targets to reduce gas consumption to 4×109 m3 (1.5 ×109 m3) and ensure over 50 % of the energy mix is carbon-neutral electricity. The paper examines three key actions based on statistical data to achieve these targets: (a) reducing natural gas dependency, (b) boosting domestic alternative sources like local gas production and green solutions, and (c) enhancing energy system flexibility through regulation, storage, and generation. These strategies are assessed for their potential to satisfy the trilemma’s demands and provide a resilient path forward amidst evolving challenges.

Open Access: Yes

DOI: 10.3303/CET24114146

The Impact of Digital Inequality on IT Identity in the Light of Inequalities in Internet Access

Joseph Squillace Richard Nemeth Justice Cappella Roland Kelemen

Publication Name: Elte Law Journal

Publication Date: 2024-01-01

Volume: 2024

Issue: 2

Page Range: 173-186

Description:

This article investigates the relationship between the United Nations Sustainable Development Goals (SDG) and Internet access, focusing on how digital connectivity influences the achievement of these global objectives. This research examines digital inequalities in access, usage, skills and outcomes through a mixed-methods approach, including statistical analysis and case studies. The findings indicate a strong correlation between Internet access and progression towards the European sustainability goals related to education quality, gender equality and industry innovation. In particular, it can be shown that where Internet access indicators are lower, digital literacy and IT identity scores are also lower for society as a whole, impacting both the quality of education and social mobility, while simultaneously reducing the economic competitiveness of the respective state. We can also see that these societies have a more patriarchal approach, negatively impacting the social status of women (although the COVID-19 epidemic negatively impacted social resilience, too) while further harming progress towards the Sustainable Development Goal associated with education. Significant disparities are also identified, particularly affecting rural areas, women, children and marginalised communities. The article futher explores IT identity, revealing that a strong IT identity enhances digital inclusion and empowerment. Article results highlight the necessity of addressing digital inequalities to ensure the equitable distribution of digital benefits and advocating for Internet access as a fundamental right essential to achieving global sustainability and Internet equality.

Open Access: Yes

DOI: 10.54148/ELTELJ.2024.2.173

Applying NeuralODE-based Cardiovascular Model Identification for Experimental Data Analysis

B. Benyo Ákos Antal J. Geoffrey Chase Bálint Szabó K. Kovacs Ákos Szlávecz

Publication Name: Saci 2024 18th IEEE International Symposium on Applied Computational Intelligence and Informatics Proceedings

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 437-442

Description:

Recent model-based diagnostic methods have been found promising to provide non-invasive perfusion markers to assess the efficacy of fluid therapy, the most common treatment method for acute circulatory failure (ACF). The development of these model-based diagnostic methods requires the identification of the central arterial pressure curve based on the femoral arterial pressure. This current study presents improvements of the previously suggested NeuralODE-based identification method by suggesting the use of a physiologically interpretable parameter set of the Tube-load model-based transfer function for the physiological system analysis and suggesting a calculation method decreasing the measurement error-caused uncertainty of the identification parameter, called pulse transfer time.

Open Access: Yes

DOI: 10.1109/SACI60582.2024.10619737

Comparison of Data Visualization Platforms Through European Traffic Data

Eniko Nagy Gombos Tamas Ferenc Gyorgy Molnar

Publication Name: Iccc 2024 IEEE 11th International Conference on Computational Cybernetics and Cyber Medical Systems Proceedings

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 43-48

Description:

The most important and valuable resource in the 21st century is data. The age of the internet brought us an era in which humans, within a foreseeable time, are unable to process the vast amount of data that we produce. It's important to understand the data and statistics we have because it can help a company make a well thought out decision on a given dilemma, which is based on reality and data. When choosing a data visualisation platform, the purpose of the application, the type of data and the user needs are also key factors. For the visualisation of traffic data in Europe, a number of established platforms can be considered and are referred to in this paper. This article compares data visualisation platforms currently available and used in industrial environments with open source free platforms, using European traffic data.

Open Access: Yes

DOI: 10.1109/ICCC62278.2024.10582968

Correlation of Biomechanical Performance Measures with Speed, Acceleration and Deceleration in Human Overground Running

Ambrus Zelei Liliána Zajcsuk

Publication Name: Springer Proceedings in Mathematics and Statistics

Publication Date: 2024-01-01

Volume: 453

Issue: Unknown

Page Range: 601-613

Description:

Earlier research results suggest that certain optimization processes take place in the human nervous system during body movement including locomotion. These processes might employ a combination of cost functions that make adaptation possible to the changing conditions, such as terrain or to certain intentions such as maintaining locomotion speed. We focus on the exploration of the changes in human body kinematics and kinetics, related to well-defined cost functions, such as energy dissipation, energy conservation or energy accumulation. These cost functions are in analogy with deceleration, constant speed locomotion and acceleration. Hence, we collected measurement data of eight athletes with five different tasks: (1) slow, (2) convenient, (3) high speed running, (4) acceleration and (5) deceleration. Correlation tests showed that the effect of varying speed and acceleration can be distinguished. The variation in running speed can be effectively indicated by the knee angle, the relative horizontal position of the center of mass and the center of foot pressure (CoM-CoP distance), the loading rate, the peak tibial shock, the foot angle and the shank angle, while the variation in the acceleration can be indicated by the angle of the trunk, the CoM-CoP distance, the average ground reaction force angle and the horizontal force components in the joints.

Open Access: Yes

DOI: 10.1007/978-3-031-56492-5_44

The Potential for Analyzing the Correlation Between the Compressive Stress Resistance of Red Clover Seeds and the Environmental Conditions during Seed Maturation Using FT-IR Spectroscopy

Eszter Kókai Gergely Zoltán Macher Dalma Bódizs Anett Bedő Marcell Lócsi Szilveszter Gergely

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 715-720

Description:

The paper aims to examine the connection between environmental conditions during seed maturation and the ability of seeds to compressive stress, supported by statistically significant findings. The study involves using Fourier transform infrared (FT-IR) spectroscopic analysis on red clover seeds under varying pressure levels, specific tensions, and selected quality parameters. The methodology relies on a general FT-IR spectroscopic approach, with spectral comparisons made against results from pressure-induced rupture. Through this research, new methods for seed testing are intended to be informed by differential and correlation results across technical parameters and different measurement settings. The analyses indicated a noticeable difference of several 10 N in visible features between seed maturation stages and compressive tolerance. Given the novelty of the aspects being explored, one primary influencing factor is identified as the scarcity of available literature, which also serves as a limitation of this research. The obtained results have potential applications for analysts, agricultural specialists, consultants, and experts involved in seed management and distribution.

Open Access: Yes

DOI: 10.3303/CET24114120