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Publications - 6278

Reducing resource use and emissions by integrating technology and policy solutions

Raymond R. Tan Yee Van Fan Petar Sabev Varbanov Ferenc Friedler

Publication Name: Clean Technologies and Environmental Policy

Publication Date: 2022-01-01

Volume: 24

Issue: 1

Page Range: Unknown

Description:

No description provided

Open Access: Yes

DOI: 10.1007/s10098-021-02237-2

Investigation of the performance of direct forecasting strategy using machine learning in State-of-Charge prediction of Li-ion batteries exposed to dynamic loads

Adrienn Dineva Bence Csomós Szabolcs Kocsis Szurke Istvan Vajda

Publication Name: Journal of Energy Storage

Publication Date: 2021-04-01

Volume: 36

Issue: Unknown

Page Range: Unknown

Description:

On account of intense technological advances regarding Electric Vehicles, the state evaluation and prediction issues of Li-ion cells have become increasingly important for ensuring the competitiveness in terms of feasible performance and range. Albeit the wide investigation of various standard modelling and estimation techniques, only limited researches focus on their precision and applicability under heavy transient working conditions. This paper is concerned with Li-ion battery terminal voltage and State-of-Charge (SoC) prediction for two types of dynamic loads. Attention is focused on the investigation of the applicability of direct multi-step forecasting strategy in combination with Machine Learning. Beside that, a feature bank is composed of discharge profiles obtained at different C-rates. The set of discharge curves is proposed to complement the feature extraction, i.e. the additional historical data is considered for model building. Special care is devoted for the design of appropriate training data. Hence, a battery cell model is built for simulating intensive dynamic load scenarios in addition to the experimental setup. The cell model is validated by using measurement data. Results have demonstrated, that in case of WLTP-type discharge load of 0.3C-rate the forecasting performance is highly efficient on measurement data. Under dynamic loads of 1C-rate, or when small historical data is available, the application of feature bank improves the performance. We have obtained comprehensive results proving that the application of direct multi-step forecasting strategy using XGBoost represents a viable alternative to capture real-time the cell dynamics and predict the terminal voltage and SoC of Li-ion batteries exposed to dynamic loads.

Open Access: Yes

DOI: 10.1016/j.est.2021.102351

Generalization capability of neural networks based on fuzzy operators

László Gál Rita Lovassy László T. Kóczy

Publication Name: Applied and Computational Mathematics

Publication Date: 2011-01-01

Volume: 10

Issue: 2

Page Range: 340-355

Description:

This paper discusses the generalization capability of neural networks based on various fuzzy operators introduced earlier by the authors as Fuzzy Flip-Flop based Neural Networks (FNNs), in comparison with standard (e.g. tansig function based, MATLAB Neural Network Toolbox type) networks in the frame of simple function approximation problems. Various fuzzy neurons, one of them based on a pair of new fuzzy intersection and union, and several other selected well known fuzzy operators (£ukasiewicz and Dombi operators) combined with standard negation have been proposed as suitable for the construction of novel FNNs. We briefly present the sigmoid function generators derived from fuzzy J-K and D flip-flops. An advantage of such FNNs is their easy hardware implementability. The experimental results show that these FNNs provide rather good generalization performance, with far better mathematical stability than the standard tansig based neural networks and are more suitable to avoid overfitting in the case of test data containing noisy items in the form of outliers.

Open Access: Yes

DOI: DOI not available

Rolling Contact fatigue Defects and a New Approach to Rail Material Management

Éva Lublóy Zoltán Major Cecília Szigeti Róbert Horváth

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2025-01-01

Volume: 22

Issue: 4

Page Range: 227-246

Description:

This article describes the current method of calculating the Hertzian contact stress and the corresponding shear stress occurring in the rail head at the rail-wheel contact and highlights the false sense of security that this approach creates among experts. The authors then present a method that is easy to implement in spreadsheet software and provides realistic results. In light of the results obtained, it is shown that it is not possible to prevent defects induced by the occurring stresses but only to keep them within limits by means of rail machining, which is a realistic objective, without significantly limiting the throughput capacity of the railway track. The combined effects of rail machining and natural wear cause the cross-sectional area and inertia and thus, the load-bearing capacity of the rails to decrease continuously. If the limit is exceeded, the rails may be installed again in less heavily used track sections and continue functioning. At the end of their service life, the track owner sells them as used rail scrap. If possible, recasting them as electro-steels, can significantly reduce the production costs and the amount of CO2 emitted during production.

Open Access: Yes

DOI: DOI not available

From Voice to Action: Upholding Children’s Right to Participation in Shaping Policies and Laws for Digital Safety and Well-Being

Enikő Kovács-Szépvölgyi Roland Kelemen Dorina Anna Tóth

Publication Name: Societies

Publication Date: 2025-09-01

Volume: 15

Issue: 9

Page Range: Unknown

Description:

While the digital environment offers new opportunities to realise children’s rights, their right to participation remains insufficiently reflected in digital policy frameworks. This study analyses the right of the child to be heard in the academic literature and in the existing international legal and EU regulatory frameworks. It explores how children’s participation right is incorporated into EU and national digital policies and examines how genuine engagement can strengthen children’s digital resilience and support their well-being. By applying the 7C model of coping skills and analysing its interaction with the right to participation, the study highlights how these elements mutually reinforce the achievement of the Sustainable Development Goals (SDGs). Through a qualitative analysis of key strategic documents and the relevant policy literature, the research identifies the tension between the formal acknowledgment of children’s right to participate and its practical implementation at law- and policy-making levels within the digital context. Although the European Union’s examined strategies emphasise children’s participation, their practical implementation often remains abstract and fragmented at the state level. While the new BIK+ strategy shows a stronger formal emphasis on child participation, this positive development in policy language has not yet translated into a substantive change in children’s influence at the state level. This nuance highlights that despite a positive trend in policy rhetoric, the essential dimension of genuine influence remains underdeveloped.

Open Access: Yes

DOI: 10.3390/soc15090243

Complex oncologic therapy for loco-regionally advanced breast cancer associated with long-lasting SARS-CoV-2 PCR-positivity

István Sipőcz Tamás Kullmann Márta Knausz Dániel Kollár András Drozgyik F. Tamás Molnár

Publication Name: Orvosi Hetilap

Publication Date: 2021-04-01

Volume: 162

Issue: 16

Page Range: 611-614

Description:

Mortality of COVID-19 is increased when certain co-morbidities, among others advanced malignancies are present. Deleterious effect of cytotoxic therapy, related to its immunosuppressive effect, may also be hypothesised. However, postponing or cancelling oncologic treatment, especially in younger patients with advanced and more aggressive tumors may worsen the prognosis. The case of a 39-year-old female patient is presented, who was diagnosed with loco-regionally advanced breast cancer during the pandemic. Primary systemic chemotherapy was started. The patient presented with acute respiratory tract symptoms during the fifth cycle and subsequently SARS-CoV-2 infection was diagnosed. Chemotherapy was cancelled. Symptoms resolved in three days after diagnosis. SARS-CoV-2 PCR remained positive up to day 43. Antihormonal therapy was introduced on day 19 and she underwent mastectomy with axillary lymph node dissection on day 51. Chemotherapy was reset postoperatively on day 82 with prophylactic G-CSF protection. No adverse event was observed throughout the treatment. Cytotoxic chemotherapy and surgery can be successfully delivered in breast cancer patients with prolonged asymptomatic SARS-CoV-2 PCR positivity, even without negative swab result. Individual optimisation of the therapy may require deviations from standard protocols. Closer multidisciplinary cooperation may contribute to the minimisation of both oncologic and infectious risks.

Open Access: Yes

DOI: 10.1556/650.2021.32192

Displacement determination by digital holographic interferometry

Lotfi Abdelhakim

Publication Name: Aip Conference Proceedings

Publication Date: 2010-12-01

Volume: 1281

Issue: Unknown

Page Range: 2089-2094

Description:

Digital Holographic Interferometry is a useful technique for measuring the deformation or displacement of the surface of an object by recording at least two speckle patterns, one before and one after the object is deformed. Holographic interferometry utilizes interference between the speckled image of an object illuminated by a laser and a reference beam derived from the same laser. Any change in the shape of the object results in local changes in the intensity distribution in the holographic fringe pattern. This optical technique allows detecting deformation with sensitivity smaller than the wavelength of light. The holograms are generated directly on a charge coupled device (CCD) target and stored electronically. The speckle patterns can be taken quickly analyzed using Holographic interferometry and Fourier transform method. © 2010 American Institute of Physics.

Open Access: Yes

DOI: 10.1063/1.3498364

Small and silly? or private pitfall of small and medium-sized enterprises

Bencsik Andrea I. Marosi V. Lore

Publication Name: World Academy of Science Engineering and Technology

Publication Date: 2009-01-01

Volume: 37

Issue: Unknown

Page Range: 482-488

Description:

Knowledge and these notions have become more and more important and we speak about a knowledge based society today. A lot of small and big companies have reacted upon these new challenges. But there is a deep abyss about knowledge conception and practice between the professional researchers and company -life. The question of this research was: How can small and mediumsized companies be equal to the demands of new economy? Questionnaires were used in this research and a special segment of the native knowledge based on economy was focused on. Researchers would have liked to know what the sources of success are and how they can be in connection with questions of knowledge acquisition, knowledge transfer, knowledge utilization in small and medium-sized companies. These companies know that they have to change their behaviour and thinking, but they are not on the suitable level that they can compete with bigger or multinational companies. © 2009 WASET.ORG.

Open Access: Yes

DOI: DOI not available

Solving contact problems using the domain decomposition method with an interface preconditioner

Lotfi Abdelhakim G. Y. Molnarka

Publication Name: Proceedings of the 6th International Conference on Engineering Computational Technology

Publication Date: 2008-12-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The present paper is concerned with the frictionless bilateral or unilateral contact problem between two elastic bodies. An algorithm is introduced to solve the resulting finite element system by a non-overlapping domain decomposition method. This technique enable us to transform the solution of the global problem to the solutions of the elasticity equations for each body separately and the solution of the Schur complement problem on the contact surface. The main goal of this work is the construction of the interface preconditioner for the Schur complement problem. The solution is obtained by using a successive approximation method. Finally, some numerical results of the proposed method are given. © 2008 Civil-Comp Press.

Open Access: Yes

DOI: DOI not available