Wyniki wyszukiwania - BazTech

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FL-MEC: federated learning for network traffic classification on the network Edge

Paszko Patryk, Konieczny Marek, Zieliński Sławomir, Kwolek Bartosz

Computer Science

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2025

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T. 26 (4)

181--201

EN

Nowadays, two technological trends, Federated Learning (FL) and Edge Computing (EC), are increasingly important and influential. FL is a decentralized machine learning strategy that allows learning on distributed data. It primarily allows performing learning operations close to the user, where the data is gathered. This approach belongs to the EC domain, where the main goal is to move computation closer to the end user (e.g., from the centralized cloud). In our work, we apply the FL and EC in the context of network flow classification. We achieved an accuracy of 0.957 with the FL model, compared to 0.924 for the best local model. We achieved these results thanks to the federated averaging performed on neural network layers. To verify our approach, we executed allour experiments on a virtualized environment that emulates existing mid-scale EC network infrastructure, including limitations related to resource constraints on edge nodes.

2

Properties and strengthening mechanisms of nickel matrix composites reinforced with high-speed steel particles

Konieczny Marek

Composites Theory and Practice

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2024

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R. 24, nr 2

116--122

EN

Nickel matrix composites reinforced with T15 high-speed steel (HSS) particles were prepared using powder metallurgy. A systematic investigation was conducted into the effects of the sintering temperature and T15 HSS particle content on the microstructure and properties of the composites. The results indicate that the grain size of the nickel in the composites was effectively refined by the addition of T15 HSS particles in comparison to the pure sintered nickel. It was also observed that the T15 HSS particles, after sintering at all the used temperatures (850, 900 or 950 °C), were diffusion-bonded to the nickel matrix. There were two distinct layers between the reinforced particles and the nickel matrix: the solid solution of elements in nickel and the FeNi3 intermetallic compound, whose thickness slowly grows with the increase in sintering temperature. Also, as the sintering temperature was incremented, the relative density and hardness of the composites gradually rose. When sintered at 950 °C, the Ni+20 wt.%T15 composite achieved a maximum hardness of 135 HB, which was about 52 % higher than that of the pure sintered nickel. The introduction of an increasing amount of T15 HSS particles combined with sintering resulted in a rise in the yield strength of the sintered composites. At all the investigated temperatures, as the T15 HSS particle content was increased, the compressive strength of the composites also gradually grew. Nonetheless, as the sintering temperature was raised from 850 to 950 °C, the compressive strength of the composites initially increased and then decreased. The composite containing 20 wt.%T15 HSS particles sintered at 900 °C achieved the highest compressive strength of 445 MPa, which was about 50 % higher than that of the pure sintered nickel. Additionally, the primary contributions of strengthening mechanisms such as load transfer, grain refinement and thermal expansion mismatch to the mechanical properties of the Ni+T15 HSS composites were analyzed.

3

Effect of deformation temperature and strain rate on compressive behavior of laminated aluminum bronze-intermetallic composites

Konieczny Marek

Composites Theory and Practice

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2020

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R. 20, nr 1

43--48

EN

Laminated composites were produced by reactive bonding using CuAl10Fe3Mn2 bronze and titanium foils with thicknesses of 0.6 and 0.1 mm, respectively. To obtain the composite sample five foils of bronze and four of titanium were used. During fabrication, the titanium layers reacted completely and formed intermetallics (Ti2Cu, TiCuAl and TiCu2Al). In order to investigate the compressive behavior of the laminated CuAl10Fe3Mn2-intermetallic composites, isothermal compression tests were conducted at the temperatures of 20, 600 and 800°C with two different strain rates of 1·10-3 s-1 and 2.9·10-3 s-1. The thickness of all the specimens was reduced by 50%. During the compression tests delamination of the layers of the composites was not observed. With an increase in the investigation temperature the yield strength of the composites decreased significantly. The results showed that the deformation temperature and the strain rate were equally responsible for the evolution of deformation during isothermal compression. The most favorable compressive deformation conditions necessary to shape the laminated CuAl10Fe3Mn2-intermetallic phases composites without damaging their layers were determined experimentally.

PL

Wytworzono kompozyty warstwowe z foli z brązu aluminiowego CuAl10Fe3Mn2 o grubości 0,6 mm oraz z foli tytanowej o grubości 0,1 mm. W celu uzyskania kompozytu zastosowano pięć folii z brązu i cztery z tytanu. Podczas reakcji syntezy warstwy tytanu całkowicie przereagowały i powstały fazy międzymetaliczne (Ti2Cu, TiCuAl i TiCu2Al). W celu przeanalizowania mechanizmu deformacji podczas ściskania kompozytów przeprowadzono testy w temperaturze 20, 600 i 800°C, stosując dwie różne prędkości odkształcania: 1·10-3 s-1 oraz 2,9·10-3 s-1. Próby prowadzono do uzyskania 50% redukcji grubości. Podczas prób ściskania nie zaobserwowano delaminacji warstw kompozytu. Stwierdzono znaczny spadek granicy plastyczności kompozytów wraz ze wzrostem temperatury badania. Wyniki pokazały, że zarówno temperatura, jak i prędkość odkształcania miały wpływ na mechanizm deformacji. Eksperymentalnie określono optymalne parametry procesu odkształcania kompozytu CuAl10Fe3Mn2-fazy międzymetaliczne pozwalające na jego kształtowanie bez niszczenia warstw.