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Found 6334 publications

Learning Factories in Practice: The Example and Development Proposal of Mini Company Located in the Automotive Science Park Based on International Best Practices †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

The focus of this study is on presenting the concept of the Mini Company initiative launched in 2023 in the ZalaZONE automotive science park and proposing its development through international good examples. The aim of the project, based on the learning factory model, is to enable dual university students to experience the real market environment in a realistic, educational environment. The search for international good examples can help to further develop the concept, especially regarding the future role of automotive stakeholders. The presented results and good examples can be used in new research projects, develop teaching methods, and strengthen cooperation between industry and academia.

Open Access: Yes

DOI: 10.3390/engproc2024079056

Friction and Wear of the Piston Ring - Cylinder Liner System with Artificially Aged Ultra-low Viscosity Engine Oils

Publication Name: Periodica Polytechnica Transportation Engineering

Publication Date: 2024-01-01

Volume: 52

Issue: 2

Page Range: 190-198

Description:

This study aims to investigate the performance of artificially aged prototype engine oils through friction and wear experiments. Experiments were performed on a piston ring - cylinder liner model system with boundary conditions derived from real-life operating conditions. The experimental design implemented two prototype oils (SAE 0W-12 and 0W-16) in unaltered and artificially aged form. An additional fully formulated off-the-shelf engine oil (SAE 0W-20) was also aged and analyzed as reference. Oil samples were artificially aged in a custom rig, to simulate long-term in-engine use through thermal cycling at 180 °C. Fourier Transformed Infrared Spectroscopy of the lubricant samples highlighted a depletion of zinc dialkyl-ditiophosphate antiwear additives in all cases, which is comparable to a selected in-service oil. Oxidation was also measurable, albeit lower compared to the in-service sample. Averaged friction coefficients showed a ranking of aged 0W-12 < aged 0W-16 < unaltered 0W-12 < unaltered 0W-16. A decrease in surface roughness was experienced with aged oil samples, whereas unaltered 0W-16 oil produced an unexpected transition in the wear phenomenon and resulted in severe wear.

Open Access: Yes

DOI: 10.3311/PPtr.22918

Performance Analysis of Position Estimation and Correction Methods †

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

There are several global and local position estimation and refinement techniques based on the GNSS (Global Navigation Satellite System) and environmental monitoring (e.g., LIDAR, Light Detection and Ranging). These are usually based on a combination of multiple sensors using some form of sensor fusion, together with a filtering or observation technique. The behavior of these algorithms may vary depending on the applied sensor signals and on their accuracy under different environmental conditions and for different vehicle types. In the case of systems that also use GNSS signals, different procedures must also be prepared for signal dropouts and, in the worst case, drastic fluctuations in accuracy. The aim of this research is to present and compare the performance of different estimation procedures for different vehicles and environmental conditions.

Open Access: Yes

DOI: 10.3390/engproc2024079061

Dynamics of Railway Wheelsets with a Nonsmooth Contact Force Model

Publication Name: Springer Proceedings in Mathematics and Statistics

Publication Date: 2024-01-01

Volume: 454

Issue: Unknown

Page Range: 41-53

Description:

The dynamics of a railway wheelset is investigated, focusing on the effect of the contact force models. For large values of creep velocities, the Coulomb model can be used as an asymptotic approximation of wheel-rail contact forces. Then, we get a nonsmooth dynamical system with codimension-2 discontinuities. At the discontinuity of the phase space, the so-called limit directions can be found, which correspond to the possible transitions between slipping and rolling. By this analysis, the nonsmooth model can complement the usual linear creep force model from the opposite direction, and we can explore more details about the qualitative behaviour of the wheelset.

Open Access: Yes

DOI: 10.1007/978-3-031-56496-3_4

Change in Stiffness of Reinforced Concrete Tunnel Walls and Its Effect Under Fire Load

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 342-350

Description:

This article uses the knowledge gained from tunnel fires to address the structural analysis of tunnel walls during fire exposure. The designing at normal temperature and its theoretical background are discussed in the literature. As these books did not yet deal with the issue of fire protection designing, we tried to supplement the existing theoretical knowledge with the knowledge provided by the relevant standards for reinforced concrete tunnel walls. In addition, we have tried to add our own individual ideas to the theory where we felt that there were gaps. The theoretical summary has been compiled in such a way that it can be easily transferred and applied to everyday practice. In this article, we discuss in detail the calculation of the internal forces in tunnel walls during fire exposure. Due to space constraints, the issue of designing at normal temperatures is only touched upon in this article, limiting it to the knowledge available in the literature. Since finite element modelling has become a commonly used technique in tunnel design since the 1970s, we use its potential to investigate the effects of earth pressure and surface loads on the tunnel walls during fire and their changes, using specific software for geotechnical design. In accordance with the limitations of the scope, the determination of the equivalent thickness and the modulus of elasticity of the tunnel wall is also presented in order to determine the internal forces during the fire action.

Open Access: Yes

DOI: 10.3233/ATDE240565

Embedded System Simulation for Electrical Hardware Test Virtualization

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 799-804

Description:

In the automotive industry, the reduction of development costs has a key importance. Also, the duration of the development is a significant aspect. Electrical hardware development is an expensive, time-consuming process with a lot of development stages (e.g., prototypes, electrical tests, mechanical tests, lifecycle tests). Virtualization is an important factor in making electrical component development more sustainable; using this method, less prototype manufacturing is necessary since the simulations make it faster and more effective to find out a large portion of possible faults without building a hardware prototype. The main goal of the paper is to explore the capabilities of seven software solutions that can manage the virtualization of the electrical development toolchain. The simulation environment should manage the simulation of the electrical circuit, including the sensors and loads, the microcontroller, and the execution and debugging of the uploaded program code. The study provides guidance on choosing the proper simulator depending on the simulation focus.

Open Access: Yes

DOI: 10.3303/CET24114134

Numerical Modeling of Multi-Pass Arc Welding Processes: Integration with Experimental Validation for Distortion analysis and Characterization

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 248-254

Description:

The increasing significance of numerical simulations in the welding industry arises from their capacity to improve manufacturing conditions, ensuring greater effectiveness and precision. The utilization of the finite element method (FEM) enables comprehensive and focused calculations of mechanical and material structural alterations induced by the welding process. Acquiring knowledge of these parameters not only serves to augment the quality of the manufacturing process but also yields consequential benefits, such as reducing adverse effects like base plate distortion. Consequently, enhancing structural performance and prolonging lifespan becomes achievable, aligning with overarching sustainability goals. To accomplish this objective, this paper involves the numerical simulation of a welding process based on experimental tests, with a focus on investigating the deformations caused by the heat generated during welding as the primary parameter of interest. Advanced modeling techniques are employed to assess the results as part of a comprehensive thermo-mechanical analysis framework, examining and characterizing the impact of the temperature distribution. In the finite element analysis (FEA), a total of 12 welding cycles were systematically modeled to align with experimental conditions, incorporating cooling intervals and preheating considerations. The outcomes of this research exemplify the potential of numerical simulation in the welding industry, demonstrating a diverse range of results achieved through FEA to enhance the quality of structures.

Open Access: Yes

DOI: 10.3233/ATDE240552

Digitalization and its tax implications: Evidence from the uk and hungary

Publication Name: Studies in Systems Decision and Control

Publication Date: 2024-01-01

Volume: 525

Issue: Unknown

Page Range: 511-520

Description:

Digitalization has transformed the way businesses operate and interact with their customers, suppliers, and governments. It has also created new challenges and opportunities for tax policy and administration. By using a literature review, this paper examines the effects of digitalization on tax in three countries: The UK and Hungary. It analyzes how these countries have adapted their tax systems to cope with the digital economy and what the main issues and trade-offs are. The paper concludes that countries need to globalize their tax policies in order to protect their tax bases in the digital economy. For this, they need to work together with international organizations to develop new international tax rules and tools for the digital economy.

Open Access: Yes

DOI: 10.1007/978-3-031-54383-8_39

Discrete Element Modelling Analysis of Particle Breakage Criteria in Direct Shear Tests

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 60-66

Description:

Discrete Element Modelling (DEM), employing the replacement method, has been extensively utilized to investigate the micro and macroscopic behavior of soil with particle breakage. Despite numerous breakage criteria proposed in the literature, an agreement on the most appropriate criterion remains unclear. In this study, three-dimensional DEM analyses were conducted using Particle Flow Code (PFC3D) to assess stress distribution and identify potential locations of particle crushing during direct shear tests for coarse sand subjected to different high normal stresses. The investigation focused on employing a breakage criterion featuring Weibull distribution of particle strengths and considers the effect of particle size on average strength to predict the occurrence of fractures. Various breakage criteria, including major principal stress, mean stress, octahedral shear stress within a particle, and stress calculated from the maximum contact force on a particle, were each examined. The findings indicate that potential crushable particles were predominantly situated near diagonal shear band. Notably, results demonstrate that criteria based on octahedral shear stress and maximum contact force prove more effective in accurately reproducing the concentration of crushed particles near the shear band.

Open Access: Yes

DOI: 10.3233/ATDE240527