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Found 6278 publications

Predicting the Impact of Product Type Changes on Overall Equipment Effectiveness through Machine Learning

János Jósvai Péter Dobra

Publication Name: Periodica Polytechnica Mechanical Engineering

Publication Date: 2023-01-01

Volume: 67

Issue: 1

Page Range: 81-86

Description:

Nowadays, Industry 4.0 and the Smart Manufacturing environment are increasingly taking advantage of Artificial Intelligence. There are more and more sensors, cameras, vision systems and barcodes in the production area, as a result of which the volume of data recorded during manufacturing and assembly operations is growing extremely fast. The interpretation and processing of such production-type data by humans is no longer possible effectively. In the Big Data domain, machine learning is playing an increasingly important role within data mining. This paper focuses on the product change processes of semi-automatic assembly line batch production and examines the impact of product type changes on the Overall Equipment Effectiveness (OEE) and attempts to determine future values through supervised machine learning. Using decision tree technology, the effect on the OEE value can be predicted with an accuracy of up to 1%. The presented data and conclusions come from a real industrial environment, so the obtained results are proven in practice.

Open Access: Yes

DOI: 10.3311/PPme.21320

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 Peter Varlaki

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

Rapid fleet condition analysis through correlating basic vehicle tracking data with engine oil ft-ir spectra

Charlotte Besser Péter Raffai András Lajos Nagy Bettina Ronai Adam Agocs J. Rohde-Brandenburger Nicole Dörr

Publication Name: Lubricants

Publication Date: 2021-12-01

Volume: 9

Issue: 12

Page Range: Unknown

Description:

Engine oil condition and tribological performance are strongly interrelated. Accordingly, oil condition monitoring is common in various applications. This is especially important, as oil condition depends on the fueling and utilization profile of an internal combustion engine. Common practice involves the measurement of various parameters, such as the total acid number and total base number, oxidation, nitration, viscosity, and elemental composition; thus, it can be time-consuming and resource-intensive. This study provides a methodology for rapid analysis for large vehicle fleets or sample sizes, using only Fourier-transformed infrared spectroscopy and the subsequent multivariate data analysis offers a rapid alternative to commonly available methods. The described method provides a rapid, cost-efficient, and intuitive approach to uncovering differences in the oil condition. Furthermore, understanding the underlying reasons in engine construction and the resulting chemical degradation is also possible.

Open Access: Yes

DOI: 10.3390/lubricants9120114

FATIGUE TOPOLOGY OPTIMIZATION UNDER CYCLIC LOADING FOR INNOVATIVE STRUCTURAL DESIGN

Majid Movahedi Rad Muayad Habashneh Géza Herczeg Gábor Erika Majid Movahedi Rad

Publication Name: Compdyn Proceedings

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 3389-3400

Description:

This study proposes a fatigue topology optimization approach for structural systems subjected to cyclic loading. Recognizing the impact of repeated loading on material endurance, the method incorporates fatigue considerations into the optimization process to enhance the durability and sustainability of load-bearing structures. By factoring in cyclic loading effects, this approach aims to reduce excessive material use while improving structural resilience, aligning with objectives for efficient and sustainable design. The proposed method is particularly useful in optimizing structural components in steel frameworks, where fatigue resistance and material efficiency are critical under dynamic loads. Emphasizing a balance between strength and durability, this study offers a practical tool for engineers aiming to design resilient structures that can endure cyclic stress without unnecessary material consumption. Furthermore, this framework is envisioned as a valuable solution for cyclic load environments, supporting more sustainable and resource-efficient engineering practices.

Open Access: Yes

DOI: 10.7712/120125.12660.25045

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

Current Issues in Effective Learning: Methodological and Technological Challenges and Opportunities Based on Modern ICT and Artificial Intelligence

Eniko Nagy Gyorgy Molnar

Publication Name: Eai Springer Innovations in Communication and Computing

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 1-11

Description:

Today, the discourse around the current issues of effective learning is increasingly centred on modern information and communication technologies (ICT) and artificial intelligence (AI)-based methodological and technological solutions. ICT tools, such as online learning platforms, virtual classrooms and digital textbooks, have significantly transformed the educational environment, providing opportunities for personalised learning and remote access. In addition, AI-based applications, such as student performance analysis and curriculum customisation, are opening up new horizons in education. AI can create adaptive learning systems that continuously adapt to the needs and progress of students, thus increasing the effectiveness of learning. But these new technologies and methods also bring with them a number of challenges. One major challenge is digital inequality, as not all students have access to ICT tools and the Internet. Furthermore, educators need to continuously develop their digital competences to keep up with technological developments and effectively integrate new methods into teaching. There are also ethical issues, in particular data protection and student privacy. New opportunities include the use of learning analytics to help educators better understand learning processes and identify areas where students need help. Interactive and gamified learning materials developed with the help of AI can make learning more motivating and enjoyable, thereby increasing student engagement. Overall, the integration of modern ICT and AI-based methods and technologies into education offers significant benefits, but their successful implementation requires adequate infrastructural support, continuous training for teachers and digital access for students. This article provides a brief summary of all these phenomena, trends, opportunities and good practices.

Open Access: Yes

DOI: 10.1007/978-3-031-81261-3_1

Biomolecule composition and draft genome of a novel, high-lipid producing Scenedesmaceae microalga

Péter Bálint Gergely Maróti Prateek Shetty Eszter Badics Norbert Incze V. Soós Vince Ördög E. Balázs

Publication Name: Algal Research

Publication Date: 2021-04-01

Volume: 54

Issue: Unknown

Page Range: Unknown

Description:

Lipid biosynthesis in microalgae can be stimulated by cultivation in low nitrogen medium. MACC-401 was isolated from the soil surface in Tres Marias (MG-Brazil). The strain shows the morphological characteristics of the Scenedesmaceae green algae. The daily biomass and lipid production of MACC-401 is remarkable, 0.36 g L−1 and 110 mg L−1, respectively. Exploration of the genetic background of this promising strain not only allows the utilization of this species for industrial-scale lipid production, but also provides genetic targets to select lipid-producing strains from microalgae collections. We conducted physiological experiments by cultivating MACC-401 in complete and N-limited media and performed genome sequencing as well as transcriptome analysis. The estimated nuclear genome size of MACC-401 is 99.503 Mbp and the chloroplast genome is 0.15 Mbp. The phylogenetic analysis confirmed that the MACC-401 belongs to the Scenedesmaceae family, and represents a genetically distinct accession in this family. A basic comparative transcriptome analysis resulted in the identification of N-starvation responsive genes, which could serve as markers to monitor the onset of lipid accumulation in algal cultures.

Open Access: Yes

DOI: 10.1016/j.algal.2020.102181

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