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Validation of the Optimal Points of Tribological Systems at Different Temperatures Determined by the DOE Method Using Lubricating Oil Doped with Nano-ZrO2 Particles †

I. Szabó Kevin Szabó

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

In this study, the design of experiments (DOE) method is used to find the optimum values of the tribological system in a 40–120 °C range with 0.1–1 wt% zirconia nanoadditives in a base oil. Significant factors were identified. The studied parameters include friction absolute integral, static friction, the wear scar diameter and the wear volume of the specimens. The measurements were carried out on a tribometer. The results were pre-estimated using statistical software; then, validation measurements were made using the estimated optimum point. The results show that the FAI value differed by 0.008, the COF value by 0.017, the WSD value by 4 μm and the WV value by 110,000 μm3. At 1 wt%, zirconia can have a positive effect at high temperatures. As temperatures increase, wear parameters decrease and friction values remain stable.

Open Access: Yes

DOI: 10.3390/engproc2024079080

Investigation of the Effects of CuO Nanoparticles on the Tribological Properties of Thermally Aged Group III Base Oil †

I. Szabó Péter Bence Pápai

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Protecting our environment is a primary focus in various industries, including the automotive sector, which aims to reduce friction and wear to minimize emissions. This study examines the effect of cupric oxide nanoparticles on artificially aged Group III base oil under lab conditions. The oil, aged using a temperature-focused method, was homogenized with 0.5 wt% cupric oxide nanoparticles. A ball-on-disc tribological system registered static and hydrodynamic friction. Wear track sizes indicated the nanoadditive’s positive impact compared to the oil without additives. The experiments revealed the anti-aging effect of cupric oxide nanoceramics. Lubricant aged with cupric oxide performed similarly to new oil, and cupric oxide nanoparticles positively affected friction and wear. The oil supplemented before aging showed better tribological results than after aging.

Open Access: Yes

DOI: 10.3390/engproc2024079082

Rattling detection of electric components

Zoltán Gazdagh J. A. Erdelyi A. Bartus B. Fukker

Publication Name: Proceedings of ISMA 2024 International Conference on Noise and Vibration Engineering and Usd 2024 International Conference on Uncertainty in Structural Dynamics

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 2799-2813

Description:

The study emphasizes the importance of detecting and addressing the issue of nonlinear phenomena in electronic components, due to their potential implications for structural integrity, damage or malfunction to sensitive electronic elements, and a reduction in overall vehicle reliability. This investigation based on time-domain experimental data facilitates rattling detection that aims to distinguish rattling from other type of nonlinearities. The sample is screwed on a fixture, which is mounted on an electrodynamic shaker that serves as the excitation source. The excitation signal is a closed loop sinusoidal sweep, measured in both directions and at different amplitudes. The paper will focus on several methods for identifying nonlinear phenomena, such as the Poincare map or Hilbert transformation. Phase plots are produced, that serve as a valuable tool for studying anomalies, which can be correlated to the extremes of Lyapunov exponents. The above methods are evaluated on their ability to separate rattling form other phenomena to identify genuine instances of rattling.

Open Access: Yes

DOI: DOI not available

Analyzing the Potential Impacts of the Speed Compliance Behavior of Autonomous Vehicles †

Richárd Horváth Balázs Horváth Attila Borsos Viktor Nagy

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Many researchers argue that autonomous vehicles (AV) will create a safer and more efficient transport infrastructure. However, some studies have drawn attention to potential problems in relation to how AVs and human-driven vehicles will co-exist. We investigated the effect of speed compliance behavior of AVs on an urban two-lane road section with alternating speed limits of 50 and 30 km/h. A Vissim microsimulation model was used where we gradually increased the traffic volume and the market penetration rate (MPR) of AVs. We found that under low traffic flow conditions the increase in MPR will lead to a decrease in the average speed and worsening of the average travel time. Under medium and, specifically, under saturated conditions, a high share of AVs can bring stability to the system. They can also significantly improve the speed compliance rate.

Open Access: Yes

DOI: 10.3390/engproc2024079063

Objective well-being level (OWL) composite indicator for sustainable and resilient cities

Attila János Trájer Viktor Sebestyén András Torma János Abonyi Endre Domokos

Publication Name: Ecological Indicators

Publication Date: 2024-01-01

Volume: 158

Issue: Unknown

Page Range: Unknown

Description:

Well-being is a critical element of the 2030 Agenda for Sustainable Development Goals. Given the complexity of the concept of well-being, it follows that its measurement requires complex, multivariate methods that can characterize the physical, economic, social and environmental aspects along with the mental state of a city. Although it is not sufficient to carry out settlement-level analyses to make cities inclusive, safe, resilient and sustainable. It is necessary to understand patterns within settlements. This work aims to present how the urban macrostructure of urban well-being indicators can be estimated based on GIS-based multilayer analysis. Open-source data, e.g. road networks, points of interest, green spaces and vegetation, are used to estimate urban well-being parameters such as noise levels, air quality and health-related impacts supplemented by climate models to assess urban resilience and sustainability. The proposed methodology integrates 24 models into six categories, namely walkability, environment, health, society, climate change and safety, which are weighted based on a multilevel Principal Component Analysis to minimize information loss for aggregated composite indicators. The study revealed two main components of the macrostructure related to well-being in the studied city: one related to the geometrical features and the other can be derived from the structure of the natural environment. In Veszprém a natural restoration of the detached house area, industrial area and downtown is recommended including developments with green and blue infrastructural elements and nature-based solutions.

Open Access: Yes

DOI: 10.1016/j.ecolind.2023.111460

Analysis of Drivers’ Path Follow Behaviour

Attila Borsos Ernö Horváth Gergő Ferenc Ignéczi

Publication Name: Proceedings of the International Conference on Informatics in Control Automation and Robotics

Publication Date: 2024-01-01

Volume: 2

Issue: Unknown

Page Range: 93-100

Description:

Lane keeping is a complex, multi-dimensional problem in terms of driving tasks. The lane-following driver models typically treat the control task as an end-to-end problem where the entire control chain is modelled as a human driver. However, the driver does not actively control the vehicle all the time, but follow a drift and compensate strategy, resulting in oscillations around their planned path. We have separated this oscillation scheme by filtering drivers’ selected offset to the centerline of the lane. It has been shown that there is a certain amount of offset error up to which drivers drift away from the planned path. At this point drivers intervene by applying torque to the steering wheel and steer the vehicle back onto the path. This type of drift and compensate strategy was modelled using Model Predictive Control (MPC) with event-based weights of its cost function. The proposed driver model calculates both the intervention point and the weights of the MPC based on real drivers’ data. As a result, the model together with the MPC can accurately plan the oscillation path of the drivers, contributing to a better understanding of how the driver tolerates offset errors.

Open Access: Yes

DOI: 10.5220/0012889100003822

Comparison of Mechanical Properties of PLA-Based Biocomposites Filled with Different Agricultural By-Products

László Lendvai Tej Singh Sándor K. Jakab

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 486-493

Description:

In this study, biopolymer composites were developed using poly(lactic acid) (PLA) as a polymer matrix. Various agricultural by-products, including flax seed meal, rapeseed straw, and mustard seed meal, were added as a reinforcement. The research aimed to provide insight into the valorization of cheap, readily available residues generated in the agricultural industry and assess the mechanical properties of composites prepared using them. The experimental fabrication was conducted by compounding PLA with agro-waste particles in 10 and 20 wt% concentrations. These components were melt mixed with a twin-screw extruder and injection molded into standardized forms. The resulting fabricated composites were tested for tensile and flexural mechanical properties and hardness. Through scanning electron microscopy, images of the natural particles were taken to better understand their structure, geometry, and possible ways of interaction between them and the PLA matrix. The results of quasi-static mechanical tests suggest that using agricultural by-products can effectively improve Young's modulus and flexural modulus of PLA but at the cost of tensile and flexural strength, which decreased with the by-products' introduction. Of the three agro-waste options, rapeseed straw emerged as the superior choice because it only marginally reduced the mechanical strength of the PLA and enhanced its stiffness the most. Hardness was the least affected property, test results showed that the added fillers did not substantially change the polymer matrix's hardness.

Open Access: Yes

DOI: 10.3233/ATDE240584

Concepts and Examples of Carbon-Free, Self-Sufficient Local Energy Systems

Balázs Vehovszky Zoltán Weltsch Ferenc Magyar Lóránt Kovács

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 931-936

Description:

The necessity of the “green revolution” in the field of energetics is not a question anymore; however, switching the current fossil fuel-based energy ecosystem to a fully renewable-based one poses enormous challenges. The historical structure of the present, centralised energy production infrastructure, as well as the fundamentally different characteristics of the three main fields of usage (electricity generation, heating and transportation), are among the most substantial hindering factors. The future energy system has to be much more flexible in several respects, with a fundamental contribution of smaller, independent energy communities. The current study focuses on the realisation aspects of such a small-scale energy community (or micro/nano-grid), considering the suitable technological solutions as well as the cost concerns. A high number of pilot projects and case studies around the world prove that the technical feasibility of a local grid/energy community is no longer a question. The real challenge is to find the appropriate incentives and strategy to catalyse the required transition at the legislation, system operator and end-user level as well. The outcomes of the present work contribute to this goal by pointing out the application potentials of a modular, scalable microgrid system based on a currently running microgrid-realization project at the ZalaZONE proving ground.

Open Access: Yes

DOI: 10.3303/CET24114156

Exploration Techniques in Reinforcement Learning for Autonomous Vehicles †

Áron Ballagi Ammar Khaleel

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Autonomous vehicles (AVs) have the potential to revolutionize the transportation system by enhancing road safety, reducing traffic congestion, and freeing drivers from monotonous tasks. Effective exploration is essential for AVs to navigate safely and adapt to dynamic environments. Reinforcement learning (RL) enables AVs to learn optimal behaviors through continuous interaction with their environment. This paper reviews recent RL research on designing exploration strategies for single- and multi-agent AV systems. It categorizes exploration methods based on underlying principles and addresses the challenges. It analyzes key RL algorithms’ strengths, limitations, and empirical performance. By compiling and analyzing the current state of research, this paper aims to facilitate future advancements in AV exploration using RL, offering insights into current trends and future directions in this evolving field.

Open Access: Yes

DOI: 10.3390/engproc2024079024