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Found 6334 publications

Measuring the Mechanical Effects of Egg Transport in Field and Modelled Conditions

T. Torma Katalin Kovácsné Gaal

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 979-984

Description:

Global food demand is expected to double by 2050, putting immense pressure on agro-food supply chains. As non-agricultural activities gain prominence within the food supply chain, a systemic approach is needed to address sustainability challenges. However, this is a learning process, because of the complexity of hatching egg transport, similar to a three-arm balance of transport condition, packaging material and egg quality. Changes made in the name of sustainability can sometimes cause unintended negative effects. Plastic trays are often favoured over paper ones for sustainability purposes in egg transport. However, they may contribute to higher egg breakage and reduced hatchability, increasing the carbon footprint due to the loss of day-old chicks. Since hatching eggs are more valuable than table eggs, any damage during transport results in greater economic loss. This study investigated the mechanical impact on eggs during 41 road transports, utilizing g-force acceleration loggers to collect data. A significant relationship was found between cargo weight, egg breakage, hatchability, embryo mortality, and g-force frequency. Seasonality also played a crucial role in hatchability, even when transport temperatures were within acceptable limits. Simulated trials using vibrating transport devices were conducted to better control mechanical impact. Eggs from one flock were used to minimize variables. Results showed a significant (P<0.05) reduction in hatchability (91.06 % vs. 82.81 %) when transported on plastic trays compared to paper ones. At higher vibration levels, even paper trays could not protect the eggs, with hatchability decreasing significantly (P<0.05) to 64.8 %. These trials indicated that plastic trays had a greater negative impact on hatchability, but at extreme impact levels (47.22 m/s2), even paper trays failed to offer adequate protection, reducing hatchability by 15.9 %. Considering both hatchability losses and egg breakage provides a more comprehensive understanding of sustainability in egg transport, raising the question of whether plastic trays are truly sustainable if transport conditions cannot be improved.

Open Access: Yes

DOI: 10.3303/CET24114164

Dynamics of Fuzzy Cognitive Maps with Uncertain Weights

István A. Harmati

Publication Name: Studies in Fuzziness and Soft Computing

Publication Date: 2024-01-01

Volume: 427

Issue: Unknown

Page Range: 121-133

Description:

In real-life problems, the weights of the connections between the concepts are often not known exactly. This uncertainty can be modelled in different ways, based on different considerations. In this chapter, we discuss two models, regarding the nature of uncertainty. Fuzzy grey cognitive maps (FGCMs) employ grey system theory to represent vagueness of the causal connections. This approach assumes that we do know the range of the unknown weight, but within this range we do not have any further information. In other words, the model assumes known extension, but unknown intension. In classical fuzzy cognitive maps the weights are single numbers, so the fuzziness is not present there. Fuzzy set valued fuzzy cognitve maps handle this known issue by assigning fuzzy sets to the connections, so in this model the intension of a weight is known, but the extension is not exactly clear. These models behave somewhat similarly to classical fuzzy cognitive maps. The final conclusion about the modelled system is based on the limiting behaviour of the iteration process. This iteration may converge to an equilibrium point, may arrive to limit cycles or may produce unstable behaviour. In this chapter, sufficient conditions for the existence and uniqueness of fixed points of fuzzy grey and fuzzy set valued FCMs are provided.

Open Access: Yes

DOI: 10.1007/978-3-031-37959-8_10

Motorcycle/Donorcycle: Improving Motorcyclist Safety in Győr, Hungary †

Brant von Goble

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Due to their high fatality rate, motorcycles, often referred to as “donorcycles” in the U.S., present unique safety challenges. In Hungary, motorcycle safety remains a critical issue despite a relatively low per capita rate of motor vehicle deaths, largely due to limited ownership and recognition. This study examines historical trends in motorcycle use in Hungary and the economic factors influencing their current prevalence. By emphasizing the crucial role of helmets and safety gear, road conditions, and environmental factors, this paper provides actionable recommendations to improve motorcycle safety in Győr and the surrounding regions. Implementing these recommendations stands to significantly reduce accidents and save lives, ensuring safer roads for all.

Open Access: Yes

DOI: 10.3390/engproc2024079032

Development of FEM Model to Simulate Radiosonde Collisions

János Jósvai Kristóf Lajber Norbert Hegyi

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 284-290

Description:

This paper deals with safety requirements for radiosondes and their possible finite element method (FEM) simulations. This article proposes a soft outer layer, which exhibits the use of a Polyurethane foam (PUR foam) layer on radiosondes. Analysis and tests of normal and PUR foam layer coated radiosonde's collisions with test targets were done. FEM models were created to model the collisions of radiosondes with virtual targets at drop tests in different scenarios. To compare and verify the virtual results, specified real-life drop test measurements were carried out. The measured data was analyzed and showed an average accuracy of 8% in force measurements, and 2.22% accuracy in duration of the tests. Based on these virtual and real-life tests it was demonstrated, that an FEM model can simulate the end result of using PUR foam layers on radiosondes. It also demonstrated that the applicable PUR foam layer increases a safer collision also increasing the chance of maintaining functionality of the radiosondes.

Open Access: Yes

DOI: 10.3233/ATDE240557

Dynamics of Rolling Wheels with Elliptical Tread Profiles

Mate Antali Gabor Kupi

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 255-262

Description:

In this paper, the dynamics of a loose wheel is considered rolling on a horizontal plane, where the tread profile of the wheel is ellipsoidal. From the equations of motion, a two-parametric family of steady motions are obtained, corresponding to the rolling motion on a circular or straight line with a uniform rotational speed and tilt angle. It is shown that compared to the geometries analysed in the literature, the elliptical tread profile leads to a significant change in the qualitative behaviour of the wheel.

Open Access: Yes

DOI: 10.3233/ATDE240553

Challenges for state regulation of decentralised community platforms

Richard Nemeth Gábor Hulkó Péter Bálint Király Richárd Németh

Publication Name: Rechtskultur

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 249-263

Description:

The rapid rise of decentralized online social networks (DOSNs) introduces a transformative shift in digital communication, moving away from centralized systems and leveraging blockchain technology to ensure user autonomy, data transparency, and resistance to censorship. While these platforms promise significant advantages, such as enhanced privacy, reduced operational costs, and increased interoperability, they also present critical legal and ethical challenges. This study explores these challenges through a multidisciplinary approach, integrating legal analysis, case studies, and theoretical frameworks. Key issues include the tension between immutability and content moderation, the complexities of jurisdiction, and the implications of blockchain splits for accountability and governance. The analysis highlights the need for hybrid solutions that combine decentralized architecture with external oversight, including stricter regulation of hard forks and designated regulatory responsibilities. The findings provide a roadmap for balancing innovation with user protection, aiming to foster sustainable, ethical development of DOSNs while addressing their inherent risks.

Open Access: Yes

DOI: DOI not available

Aspects of Fragility in Bosnia and Herzegovina

Eszter Kazinczy

Publication Name: Montenegrin Journal of Economics

Publication Date: 2024-01-01

Volume: 20

Issue: 2

Page Range: 145-154

Description:

Bosnia and Herzegovina remains a country with a number of deeply rooted structural challenges, which are linked to the political and the broader social sphere. The current paper provides an overview on a range of key factors that have led to the country’s fragility. During the analysis we start with the concerns related to multi-ethnic democracies, and specifically to Bosnia and Herzegovina’s unique state structure. The latter was founded in 1995, in line with the so-called Dayton Peace Agreement. We also touch upon variables that are connected to the economic and social fields, by discussing indicators that are related to labor market distortions or the level of corruption. The study provides an overview on Bosnia and Herzegovina’s position referring to international fragility indexes. Based on the analysis, we find various aspects that raise concerns regarding Bosnia and Herzegovina’s fragility.

Open Access: Yes

DOI: 10.14254/1800-5845/2024.20-2.12

Sensitivity to Geometric Detail in Fatigue Simulation of Electronic Components of Vehicles †

Ambrus Zelei Zoltán Z. Kovács

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

Solder joints strongly determine the lifetime of electronic components subjected to temperature fluctuations. The lifetime predictions obtained by finite element analysis (FEA) are uncertain due to the significant variation in solder geometry. It is unclear how realistic a geometric model is needed for problems of impartial complexity. A balance must be found between modeling effort and simulation accuracy. Six geometric models of the solder joint of a gullwing lead were built with different complexity, from the simplest to the most realistic, including a realistic reference model obtained by the Surface Evolver simulation software. The FEA results considering linear elastic and plastic material models were compared for the different solder geometries. We conclude that manually created solder geometry is a sufficient alternative to physics-based realistic geometries.

Open Access: Yes

DOI: 10.3390/engproc2024079084

An Improved Bulk Viscosity Method for Contact-Impact Problems

Balázs Pere Daniel Serfozo

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2024-01-01

Volume: 21

Issue: 8

Page Range: 243-262

Description:

Dynamic contact and impact problems are widely applicable. An accurate solution for these kinds of problems could be used in many fields of mechanical engineering (e.g., cutting metalwork, cogwheel drives, etc.). However, the proper handling of the contact is problematic, as there emerges a substantial amount of nonlinearity in the displacement field. Therefore, a spurious high frequency oscillation is present in the solution. These oscillations must be avoided, as divergence can easily occur in the contact algorithm due to them. In order to eliminate this effect, the applied numerical method must be chosen and set properly. In this study, we focused on the best possible elimination of these oscillations by which the choice of the proper numerical method has a great importance.

Open Access: Yes

DOI: 10.12700/APH.21.8.2024.8.13