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Found 6423 publications

Biharmonic Scattered Data Interpolation Based on the Method of Fundamental Solutions

Csaba Gáspár

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2023-01-01

Volume: 14076 LNCS

Issue: Unknown

Page Range: 485-499

Description:

The two-dimensional scattered data interpolation problem is investigated. In contrast to the traditional Method of Radial Basis Functions, the interpolation problem is converted to a higher order (biharmonic or modified bi-Helmholtz) partial differential equation supplied with usual boundary conditions as well as pointwise interpolation conditions. To solve this fourth-order problem, the Method of Fundamental Solutions is used. The source points, which are needed in the method, are located partly in the exterior of the domain of the corresponding partial differential equation and partly in the interpolation points. This results in a linear system with possibly large and fully populated matrix. To make the computations more efficient, a localization technique is applied, which splits the original problem into a sequence of local problems. The system of local equations is solved in an iterative way, which mimics the classical overlapping Schwarz method. Thus, the problem of large and ill-conditioned matrices is completely avoided. The method is illustrated via a numerical example.

Open Access: Yes

DOI: 10.1007/978-3-031-36027-5_38

The Role and Awareness of Food Rescue Ngos in Hungary: Based on the Results of an Online Survey

Péter Huszka Veronika Keller

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 739-744

Description:

The issue of food waste is a significant global challenge that is closely linked to the United Nations Sustainable Development Goals (SDGs). Non-governmental organisations (NGOs) are of critical importance in addressing this issue, spearheading initiatives aimed at curbing overproduction and waste. This study introduces the principal non-governmental organisations (NGOs) engaged in food waste reduction and assesses the extent of public awareness of their activities in Hungary. The research is based on secondary data and an online survey of 231 respondents. It explores initiatives such as shopping communities, the Hungarian Food Bank Association, the No Leftovers program, and the Munch app. The findings indicate that food rescue organisations are not widely recognised, which constrains their potential impact. However, younger generations demonstrate greater engagement with digital food-saving solutions. The lack of public awareness underscores the necessity for enhanced marketing and educational initiatives. Furthermore, the study identifies a generational and socioeconomic divide, with younger, higher-income individuals demonstrating a greater commitment to sustainable practices. The study offers insights into how NGOs can enhance their impact through the strategic use of technology and targeted communication.

Open Access: Yes

DOI: 10.3303/CET24114124

MORE THAN REPORTING: ENTERPRISE RESOURCE PLANNING AS ENABLER OF BUSINESS MODEL TRANSFORMATION FOR CLIMATE CHANGE MITIGATION

Yuriy Bilan Adalberto Rangone Liliana Ionescu-Feleagă Sînziana Maria Rîndaș

Publication Name: Journal of Business Economics and Management

Publication Date: 2026-03-20

Volume: 27

Issue: 2

Page Range: 262-284

Description:

Enterprise resource planning (ERP) systems are evolving to support organisations in addressing their climate impact. Yet, there is a paucity of empirical and cross-sectoral data on how these solutions can mitigate organisations’ negative climate impact through changes in business models. By focusing on a dataset of ERP-related patents published between 2020 and 2024, within a climate change classification, this study aims to shed light on how ERP-based solutions can enable business model transformation to improve environmental performance and to investigate Industry 4.0 technologies that facilitate such mitigations. Through a pragmatic inductive approach employing mixed methods, the study uncovers three main areas of business model transformation for climate change mitigation: production optimisation, sustainability management and monitoring, and supply chain performance improvement. While most of the examined patents prioritise production optimisation, the findings reveal the emergence of novel applications designed to enhance organisational sustainability management and monitoring. Furthermore, the research emphasises unexploited opportunities to enhance ERPs through the integration of Industry 4.0 technologies. This study provides a substantial contribution to the existing literature by focusing on a significant yet underexplored area: ERP-based solutions designed to enable business model transformation to mitigate climate change, with implications for researchers, organisational adopters, and system developers.

Open Access: Yes

DOI: 10.3846/jbem.2026.26451

Decreased Expression of Placental Proteins in Recurrent Pregnancy Loss: Functional Relevance and Diagnostic Value

Offer Erez Padma Murthi Nándor Gábor Than Dániel Györffy Lajos Veress Zoltán Papp Sándor Nagy Andrea Balogh László Orosz Eszter Tóth Gergő Orosz Máté Posta Orsolya Oravecz Nándor Ács Gábor Szalai András Szilágyi Olga Török Petronella Hupuczi

Publication Name: International Journal of Molecular Sciences

Publication Date: 2024-02-01

Volume: 25

Issue: 3

Page Range: Unknown

Description:

Miscarriages affect 50–70% of all conceptions and 15–20% of clinically recognized pregnancies. Recurrent pregnancy loss (RPL, ≥2 miscarriages) affects 1–5% of recognized pregnancies. Nevertheless, our knowledge about the etiologies and pathophysiology of RPL is incomplete, and thus, reliable diagnostic/preventive tools are not yet available. Here, we aimed to define the diagnostic value of three placental proteins for RPL: human chorionic gonadotropin free beta-subunit (free-β-hCG), pregnancy-associated plasma protein-A (PAPP-A), and placental growth factor (PlGF). Blood samples were collected from women with RPL (n = 14) and controls undergoing elective termination of pregnancy (n = 30) at the time of surgery. Maternal serum protein concentrations were measured by BRAHMS KRYPTOR Analyzer. Daily multiple of median (dMoM) values were calculated for gestational age-specific normalization. To obtain classifiers, logistic regression analysis was performed, and ROC curves were calculated. There were differences in changes of maternal serum protein concentrations with advancing healthy gestation. Between 6 and 13 weeks, women with RPL had lower concentrations and dMoMs of free β-hCG, PAPP-A, and PlGF than controls. PAPP-A dMoM had the best discriminative properties (AUC = 0.880). Between 9 and 13 weeks, discriminative properties of all protein dMoMs were excellent (free β-hCG: AUC = 0.975; PAPP-A: AUC = 0.998; PlGF: AUC = 0.924). In conclusion, free-β-hCG and PAPP-A are valuable biomarkers for RPL, especially between 9 and 13 weeks. Their decreased concentrations indicate the deterioration of placental functions, while lower PlGF levels indicate problems with placental angiogenesis after 9 weeks.

Open Access: Yes

DOI: 10.3390/ijms25031865

Synthesis of Integrated Vertical Farming Systems with Multiperiodic Resource Availability

Jean Pimentel Ferenc Friedler

Publication Name: Chemical Engineering Transactions

Publication Date: 2022-01-01

Volume: 94

Issue: Unknown

Page Range: 1039-1044

Description:

Vertical farming (VF) has been proposed as an approach to decrease the land required for growing agricultural products. This technique consists of growing produce in vertical orientation within a controlled environment. However, one of the most significant barriers for its implementation is the uncertain economic feasibility, derived from the elevated consumption of energy and the high investment costs. A strategy to enhance VF efficiency proposes its integration with municipal infrastructure, thus establishing closed-loop systems where VF seizes organic waste, manure, CO2, and excess energy from productive plants and local power stations. Because of the economic uncertainty of its development, the optimal synthesis of such a closed-loop system (i.e., the selection and specification of its components, and their connections) is of utmost importance for the implementation of this strategy. The difficulty of the synthesis task arises from the combinatorial nature of the problem and the variability of the resources and market conditions in time. This work employs a graph-theoretic approach for the synthesis of a closed-loop system of VF considering the variability of the resources during multiple periods of operation. The proposed method relies on the P-graph framework which permits the identification of the n-best alternatives for the system’s design, employing the properties of the problem’s structure to enhance the effectiveness of the solution procedure. Consequently, the most cost-effective systems are identified together with their policy of operation for the different periods. This method constitutes a powerful tool for the assessment of systems for VF integration that enhance the sustainability of agricultural activity.

Open Access: Yes

DOI: 10.3303/CET2294173

Blockchain research in healthcare: a bibliometric review and current research trends

Horst Treiblmaier Suhaiza Zailani Abderahman Rejeb Karim Rejeb

Publication Name: Journal of Data Information and Management

Publication Date: 2021-06-01

Volume: 3

Issue: 2

Page Range: 109-124

Description:

The literature on blockchain-enabled use cases has grown exponentially over recent years. Yet, studies are missing that apply bibliometrics and visualization techniques to unravel the dynamics and current discussions pertaining to the nexus of blockchain technology (BCT) and the healthcare field. To close this knowledge gap, we examine the knowledge base and research hotspots of BCT research in the field of healthcare. We carry out a series of bibliometric analyses on the extant literature, including the scholarly production, developmental pattern of the annual total number of authors, and identification of productive academic institutions, countries, and leading authors. Additionally, we conduct a keyword co-occurrence analysis and identify the major research hotspots and trends for the future. The findings of this research are valuable for scholars and practitioners who seek to better understand the development status, dynamics, and trends pertaining to BCT in healthcare.

Open Access: Yes

DOI: 10.1007/s42488-021-00046-2

Methods for improving the mid-frequency acoustic simulation of a lightly damped plate

Dániel Feszty Marcell Treszkai Tamas Turcsik Janos Kun

Publication Name: Proceedings of 2020 International Congress on Noise Control Engineering Inter Noise 2020

Publication Date: 2020-08-23

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The constantly evolving customer demands in the automotive industry necessitates vehicle manufacturers to perform ever more accurate acoustic simulations. Acoustic simulations especially in the mid-frequency range (400 Hz - 1000 Hz) pose particular challenges: statistical methods lack the necessary modal density for accuracy, while Finite Element Methods (FEM) have difficulty accounting for statistical effects. In order to resolve the conflict that FEM solvers face, an academic case is investigated. A flat plate of 650x 750 mm in free-free condition is examined as a low-complexity platform to investigate the sensitivity of FEM simulation results to parameters, such as the value of structural damping, the frequency dependency of structural damping as well as the variations in the plate thickness due to manufacturing tolerances. FEM simulations were performed using ESI VPS and compared to measurements. Results show that slight variations in plate thickness and Young`s modulus can have significant impact on the frequency response. Results have shown that a 0.5% variation in the thickness already has a pronounced effect on frequency response peak locations, especially between 600 and 1000 Hz. Beside this, the paper provides novel results on evaluating the effects of frequency dependency of structural damping on the results.

Open Access: Yes

DOI: DOI not available

Literature Review of Vibroacoustic Simulation in Geared Vehicle Power Transmission Systems for the Reduction of Radiated Noise

Ambrus Zelei Krisztián Horváth

Publication Name: Advances in Science and Technology

Publication Date: 2024-01-01

Volume: 153

Issue: Unknown

Page Range: 89-98

Description:

The radiated noise reduction of vehicular power transmission systems is one of the most actively researched areas. Noise not only impacts the comfort and safety of the driver and passengers but also regulated by the legislators. The simulation-based prediction of radiated noise of gear-drives is a rapidly evolving area and combines gear meshing models, finite element analysis, multibody dynamics and airborne noise simulation tools. The interfacing of these tools makes virtual noise prediction challenging. In this research, we conducted a literature review on vibroacoustic simulations, with a particular focus on reducing noise in power transmission systems. Based on the reviewed articles, it became evident that, although numerous measurement data are available, the usability of the data is limited. Most research focuses on individual stages of the structure and on smaller-sized powertrains. The measurement methods contain abundant valuable information; however, the literature lack of comprehensive articles that track the simulation process from the inception of excitation to body and air noises. Moreover, the majority of articles investigate the relationship between transmission error and NVH, considering it as a primary source of noise. New methodological approaches, such as the application of FEM meshes on gears, open new horizons in this domain. Throughout the literature review, we compiled potential noise-reduction solutions and highlighted directions for future methodology development research.

Open Access: Yes

DOI: 10.4028/p-Ucpx27

A regularized multi-level technique for solving potential problems by the method of fundamental solutions

Csaba Gáspár

Publication Name: Engineering Analysis with Boundary Elements

Publication Date: 2015-06-03

Volume: 57

Issue: Unknown

Page Range: 66-71

Description:

The method of fundamental solutions is investigated in the case when the source points are located along the boundary of the domain of the original problem and coincide with the collocation points. The appearing singularities are eliminated by several techniques: by using approximate but continuous fundamental solutions (regularization) and via auxiliary subproblems to avoid the stronger singularities that appear in the normal derivatives of the fundamental solution (desingularization). Both monopole and dipole formulations are investigated. A special iterative solution algorithm is presented, which converts the original (mixed) problem to a sequence of pure Dirichlet and pure Neumann subproblems. The pure subproblems can be handled efficiently by using conjugate gradients. The efficiency is significantly increased by embedding the resulting method in a natural multi-level context. At the same time, the problem of the use of highly ill-conditioned matrices is also avoided.

Open Access: Yes

DOI: 10.1016/j.enganabound.2014.05.002