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Found 6383 publications

Schur complement method with iterative solver for 2D fieldcircuit coupling finite element problem with movement

Miklós Kuczmann Dániel Marcsa

Publication Name: Przeglad Elektrotechniczny

Publication Date: 2014-12-01

Volume: 2014

Issue: 12

Page Range: 145-148

Description:

The analysis and design of electromechanical devices involve the solution of large sparse linear systems, and require therefore high performance algorithms. In this paper, the Schur complement method with parallel preconditioned conjugate gradient (PCG) solver is introduced in two-dimensional parallel time-stepping finite element formulation to analyse rotating machine considering the electromagnetic field, external circuit and rotor movement. The proposed parallel solver is analysed concerning its computational efficiency and number of iterations. Simulation results of a rotating machine are also presented.

Open Access: Yes

DOI: 10.12915/pe.2014.12.35

Structural behavior of built-up I-shaped cold-formed steel beams with edge-stiffened holes, unstiffened holes, plain webs, and batten reinforcement

Ardalan B. Hussein F. Papp

Publication Name: Results in Engineering

Publication Date: 2025-12-01

Volume: 28

Issue: Unknown

Page Range: Unknown

Description:

Perforated cold-formed steel (PCFS) back-to-back channel beams are increasingly gaining popularity in the building sector due to their numerous advantages and economic benefits. Notably, their lightweight nature allows for easier handling and installation, while the holes in PCFS beams facilitate the accommodation of utilities such as electrical and plumbing installations. In this study, a geometrically and materially nonlinear finite element model (FEM) was developed and validated using experimental data from existing literature. The validation results indicated a strong correlation, with the ratios of FEM and Direct Strength Method (DSM) predictions to experimental outcomes being 1.007 and 0.945, respectively. This demonstrates a significant agreement among experimental data, FEM analysis, and moment capacity estimations based on American Iron and Steel Institute (AISI) Standards, although AISI predictions were found to underestimate moment capacities by approximately 5.5 %. Following model validation, an extensive parametric study involving 192 FEM simulations was conducted to evaluate the influence of hole size, hole geometry, edge stiffeners, and batten reinforcements on the moment-carrying capacity of built-up I-shaped CFS beams. The findings indicate that, in comparison with beams having plain webs, the presence of web openings leads to a reduction in moment capacity of approximately 10 %, 9 %, 9 %, and 6 % for circular, slotted, square, and rectangular holes, respectively. Furthermore, the results demonstrate that the inclusion of stiffeners around web openings, together with batten reinforcement, markedly improves the structural performance of PCFS built-up beams. In particular, the maximum enhancement in moment capacity of beams with batten reinforcement and edge-stiffened holes, relative to those with unstiffened holes, is about 9 %, 10 %, 13 %, and 14 % for circular, rectangular, square, and slotted holes, respectively. Overall, the findings offer valuable insights into the structural behavior of perforated built-up CFS beams and emphasize the effectiveness of web hole stiffening and batten reinforcement strategies in mitigating strength reductions caused by web perforations.

Open Access: Yes

DOI: 10.1016/j.rineng.2025.107545

VR as a Medium of Communication: From Memory Palaces to Comprehensive Memory Management

Péter Galambos Adam Csapo Ildiko Horvath Péter Baranyi

Publication Name: 9th IEEE International Conference on Cognitive Infocommunications Coginfocom 2018 Proceedings

Publication Date: 2018-07-02

Volume: Unknown

Issue: Unknown

Page Range: 389-394

Description:

This paper investigates the unique potential of VR environments to serve as a comprehensive tool for communication and memory management. The paper uncovers intricate - and in some sense holistic - links between certain kinds of VR spaces and existing frameworks for the design and analysis of conceptual mappings, and shows how VR spaces can do more than just provide appealing visual experiences, by capturing the psychology of how new memories are formed. The paper provides multiple examples from the MaxWhere VR platform to support its main arguments, and concludes with a discussion on what these arguments, if accepted as correct, will mean for AI-enhanced CogInfoCom systems in the future.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2018.8639896

Multi-level meshless methods based on direct multi-elliptic interpolation

Csaba Gáspár

Publication Name: Journal of Computational and Applied Mathematics

Publication Date: 2009-04-15

Volume: 226

Issue: 2

Page Range: 259-267

Description:

A short overview on the direct multi-elliptic interpolation and the related meshless methods for solving partial differential equations is given. A new technique is proposed which produces a biharmonic interpolation along the boundary and solves the original problem inside the domain. An error estimation is also derived. To implement the method, quadtree-based multi-level methods are used. The approach avoids the use of large, dense and ill-conditioned matrices and significantly reduces the computational cost. © 2008 Elsevier B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/j.cam.2008.08.005

Digital Resilience and the “Awareness Gap”: An Empirical Study of Youth Perceptions of Hate Speech Governance on Meta Platforms in Hungary

Roland Kelemen Zsófia Réti Dorina Bosits

Publication Name: Journal of Cybersecurity and Privacy

Publication Date: 2026-02-01

Volume: 6

Issue: 1

Page Range: Unknown

Description:

Online hate speech poses a growing socio-technological threat that undermines democratic resilience and obstructs progress toward Sustainable Development Goal 16 (SDG 16). This study examines the regulatory and behavioral dimensions of this phenomenon through a combined legal analysis of platform governance and an empirical survey conducted on Meta platforms, based on a sample of young Hungarians (N = 301, aged 14–34). This study focuses on Hungary as a relevant case study of a Central and Eastern European (CEE) state. Countries in this region, due to their shared historical development, face similar societal challenges that are also reflected in the online sphere. The combination of high social media penetration, a highly polarized political discourse, and the tensions between platform governance and EU law (the DSA) makes the Hungarian context particularly suitable for examining digital resilience and the legal awareness of young users. The results reveal a significant “awareness gap”: While a majority of young users can intuitively identify overt hate speech, their formal understanding of platform rules is minimal. Furthermore, their sanctioning preferences often diverge from Meta’s actual policies, indicating a lack of clarity and predictability in platform governance. This gap signals a structural weakness that erodes user trust. The legal analysis highlights the limited enforceability and opacity of content moderation mechanisms, even under the Digital Services Act (DSA) framework. The empirical findings show that current self-regulation models fail to empower users with the necessary knowledge. The contribution of this study is to empirically identify and critically reframe this ‘awareness gap’. Moving beyond a simple knowledge deficit, we argue that the gap is a symptom of a deeper legitimacy crisis in platform governance. It reflects a rational user response—manifesting as digital resignation—to opaque, commercially driven, and unaccountable moderation systems. By integrating legal and behavioral insights with critical platform studies, this paper argues that achieving SDG 16 requires a dual strategy: (1) fundamentally increasing transparency and accountability in content governance to rebuild user trust, and (2) enhancing user-centered digital and legal literacy through a shared responsibility model. Such a strategy must involve both public and private actors in a coordinated, rights-based approach. Ultimately, this study calls for policy frameworks that strengthen democratic resilience not only through better regulation, but by empowering citizens to become active participants—rather than passive subjects—in the governance of online spaces.

Open Access: Yes

DOI: 10.3390/jcp6010003

Synthesis and Techno-Economic Analysis of Pyrolysis-Oil-Based Biorefineries Using P-Graph

Botond Bertok Abid H. Tanzil Anamaria Paiva Pinheiro Pires Lina Martinez-Valencia István Heckl Juan C. García-Ojeda Ferenc Friedler Manuel Garcia-Perez Andres Argoti

Publication Name: Energy and Fuels

Publication Date: 2021-08-19

Volume: 35

Issue: 16

Page Range: 13159-13169

Description:

The production of renewable fuels and chemicals is a critical component of global strategies to reduce greenhouse gas emissions. In this regard, pyrolysis oil obtained from biomass comprises hundreds of chemical compounds, thus rendering it a good precursor for manufacturing a variety of fuel products of commercial interest. Despite the large number of contributions describing the products' extraction, upgrading, and potential refining schemes, no bio-oil refinery is currently in operation. The main challenge in building a bio-oil refinery lies in the lack of an economically viable process configuration. Systematic studies comparing alternative refinery concepts, or configurations, are needed to identify the most promising configuration. To the best of our knowledge, this study is the first to use process graph (P-graph) methodology for the synthesis of pyrolysis oil refineries. In particular, this work shows the effectiveness of P-graph methodology in simultaneously calculating the profitability of various biorefinery designs by using data reported in the literature and providing information on how the introduction of new technologies to the database will impact the formation of profitable biorefinery concepts. Our work demonstrates a methodology for the addition of new unit operations to the database generated from the literature. The addition of a centrifuge for water extraction and a wet oxidation system for acetic acid production resulted in the generation of 330 biorefinery configurations, seven of which have a profitability ranging from $1,650 to $23,666/h (USD) with acetic acid and levoglucosan as the main products, respectively. This demonstrates that P-graph methodology is useful for discovering optimum techno-economic scenarios that may otherwise be overlooked.

Open Access: Yes

DOI: 10.1021/acs.energyfuels.1c01299

An Analysis of Consumer Decision-Making in Digital Mobile Payment Adoption: Exploring Influencing Factors

Laszlo Vasa Mohammad Fakhrul Islam Md Billal Hossain Belal Mahmoud AlWadi Tulkin Kazakov Muhammad Usman Khan

Publication Name: Decision Making Applications in Management and Engineering

Publication Date: 2024-01-01

Volume: 7

Issue: 1

Page Range: 651-675

Description:

Despite every one of the upsides of mobile payment services (MPs), they are unutilized by a sizable client base. This paper analyzes the central drivers of utilizing MPs for purchasing purposes from the consumers' point of view in Uzbekistan. Given the Technology Acceptance Model (TAM), the study built up a seven-figure model to uncover the determinants of customers' goals to utilize MPs. 300 respondents in Uzbekistan were selected, and 276 substantial responses were incorporated into the analysis. The structural equation model results applied that customers' goal to utilize MPs for purchasing purposes is impacted by trust, system usefulness, social influence, risk, hedonic motivation, and attitude. The factor, facilitating conditions was not significant interestingly which the most distinct finding of that study is. Considering the findings and discussion, the paper concludes with the notion that mobile payment as a digital innovative financial technology is influenced by most of the factors that mobile operators should look at closely.

Open Access: Yes

DOI: 10.31181/dmame7120241287

Design of load torque and mechanical speed estimator of PMSM with unscented Kalman filter-An engineering guide

Karol Kyslan Frantisek Durovsky Viliam Fedak Viktor Slapak Krisztián Horváth

Publication Name: International Conference on Electical Drives and Power Electronics

Publication Date: 2017-11-27

Volume: 2017-October

Issue: Unknown

Page Range: 297-302

Description:

This paper presents the design of Unscented Kalman Filter (UKF) for estimation of state space variables of permanent magnet synchronous machine (PMSM). The UKF is shown together with the field oriented speed control. At first, the position and the speed of PMSM are measured, and UKF is used only for a load torque estimation. It is indicated how differences in sampling time of the speed and the current loop affects overall estimation performance. Subsequently, speed sensorless performance of the UKF with the same parameters is shown for comparison. Designed filter is verified only by Matlab simulation.

Open Access: Yes

DOI: 10.1109/EDPE.2017.8123249

Introducing LEAF: LLM Edge Assessment Framework for Generative AI on the Edge

Sandor R. Repas Mustafa Abdulkadhim

Publication Name: Machine Learning and Knowledge Extraction

Publication Date: 2026-02-01

Volume: 8

Issue: 2

Page Range: Unknown

Description:

The transition of Large Language Models (LLMs) from centralized clouds to edge environments is critical for addressing privacy concerns, latency bottlenecks, and operational costs. However, existing edge benchmarking frameworks remain tailored to discriminative Deep Learning tasks (e.g., object detection), failing to capture the multidimensional challenges of generative AI, specifically the trade-offs between token generation speed, semantic accuracy, and hardware sustainability. To address this gap, we introduce LEAF (LLM Edge Assessment Framework), a novel evaluation methodology that integrates Circular Economy principles directly into performance metrics. LEAF assesses edge deployments across five synergistic pillars: Circular Economy Score, Energy Efficiency (Joules/Token), Performance Speed (Tokens/Second), semantic accuracy (BERTScore), and End-to-End Latency. We validate LEAF through an extensive experimental analysis of five distinct hardware classes, ranging from embedded IoT devices (Raspberry Pi 4 and 5, NVIDIA Jetson Nano) to professional edge servers (NVIDIA T400) and repurposed legacy workstations (NVIDIA GTX 1050 Ti). Utilizing 4-bit quantized models via the Ollama runtime, our results reveal a counterintuitive insight: repurposed consumer hardware significantly outperforms modern purpose-built edge SoCs. The legacy GTX 1050 Ti achieved a 20× speedup over the Raspberry Pi 4 and maintained superior energy-per-task efficiency compared to low-power ARM architectures by minimizing active runtime. These findings challenge the prevailing narrative that newer silicon is essential for Edge AI, demonstrating that sustainable, high-performance inference can be achieved by extending the lifecycle of existing hardware. LEAF thus provides a blueprint for a “Green Edge” ecosystem that balances computational capability with environmental responsibility.

Open Access: Yes

DOI: 10.3390/make8020048