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1

Method of Analysis of Thermophysical Properties and Composition of Nuclear Fuel During Modernization of Active Zones of Nuclear Power Reactors

Vashchenko Volodymyr, Skalozubov Volodymyr, Korduba Iryna, Komarov Yuriy, Zhukova Olena

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

186--191

EN

The developed alternative method of analyzing the safety of the active zone of reactor installations is justified for improving the thermophysical properties and composition of nuclear fuel, designs of heat-releasing assemblies, reactor operation modes at increased or reduced power, etc. The impact of modernization on the safety criteria and conditions of reactor installations (RF) was analyzed. Attention was focused on the fact that until now there have been no sufficiently substantiated and accepted criteria and conditions for "steam" explosions in the Russian Federation. It was shown that when analyzing the safety of HF modernization with deterministic codes, it is necessary to take into account the possibility of negative effects of "user code" (EUC) and "code difference" (ECD), which can significantly affect the results of re-simulation of accidents with deterministic codes taking into account modernizations.

2

A novel, machine learning-based feature extraction method for detecting and localizing bearing component defects

Cherif Bilal Djamal Eddine, Seninete Sara, Defdaf Mabrouk

Metrology and Measurement Systems

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2022

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Vol. 29, nr 2

333--346

EN

Vibration analysis for conditional preventive maintenance is an essential tool for the industry. The vibration signals sensored, collected and analyzed can provide information about the state of an induction motor. Appropriate processing of these vibratory signals leads to define a normal or abnormal state of the whole rotating machinery, or in particular, one of its components. The main objective of this paper is to propose a method for automatic monitoring of bearing components condition of an induction motor. The proposed method is based on two approaches with one based on signal processing using the Hilbert spectral envelope and the other approach uses machine learning based on random forests. The Hilbert spectral envelope allows the extraction of frequency characteristics that are considered as new features entering the classifier. The frequencies chosen as features are determined from a proportional variation of their amplitudes with the variation of the load torque and the fault diameter. Furthermore, a random forest-based classifier can validate the effectiveness of extracted frequency characteristics as novel features to deal with bearing fault detection while automatically locating the faulty component with a classification rate of 99.94%. The results obtained with the proposed method have been validated experimentally using a test rig.

3

Applicability of machine learning techniques for multi-time step ahead runof forecasting

Bajirao Tarate Suryakant, Elbeltagi Ahmed, Kumar Manish, Pham Quoc Bao

Acta Geophysica

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2022

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Vol. 70, no 2

757--776

EN

Precise and reliable runoff forecasting is crucial for water resources planning and management. The present study was conducted to test the applicability of different data-driven techniques including artificial neural networks (ANN), support vector machine (SVM), random forest (RF) and M5P models for runoff forecasting for the lead time of 1 day and 2 days in the Koyna River basin, India. The best input variables for the development of the models were selected by applying the Gamma test (GT). Two different scenarios were considered to select the input variables for 2 days ahead runoff forecasting. In the first scenario, the output of 1 day ahead runoff (t+1) was not used as an input while it was also used as an input along with other input variables for the development of the models in the second scenario. For 2 days ahead runoff forecasting, the models developed by adopting the second scenario performed more accurately than that of the first scenario. The RF model performed the best for 1 day ahead runoff forecasting with root mean square error (RMSE), coefficient of efficiency (CE), correlation coefficient (r) and coefficient of determination (R2 ) values of 168.94 m3 /s, 0.67, 0.84 and 0.704, respectively, during the test period. For 2 days ahead runoff forecasting, RF and ANN models performed the best in the first and second scenario, respectively. In 2 days ahead runoff forecasting, RMSE, CE, r and R2 values were observed to be 169.72 m3 /s, 0.67, 0.84, 0.7023 and 148.55 m3 /s, 0.74, 0.87, 0.76 in the first and second scenarios, respectively, during the test period. Finally, the results revealed that the addition of 1 day ahead runoff forecast increased the forecast accuracy of 2 days ahead runoff forecasts. In addition, the dependability of the various models was determined using the uncertainty analysis.

4

A S-band Inverted 3-way Doherty amplifier with GaN HEMT transistors

Góralczyk Marcin

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2021

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nr 4

97--101

EN

This article presents partial result of the PhD thesis on the topic of the Doherty power amplifiers. The design of high-efficiency 3way Doherty amplifier with the use of Wolfspeed CG2H40010 transistors is presented. A newly invented 3-way power splitter architecture is also shown. The proposed splitter and the properties of GaN HEMT technology enable the design of the Inverted 3-way Doherty amplifier in closed, compact form without additional, long phase lines. The amplifier operates in the frequency range from 3.4 to 3.8 GHz and achieves up to 46W of saturated output power with a drain efficiency of 75% at full drive and 53% at 10dB output power back-off.

PL

Przedstawiono częściowe wyniki pracy doktorskiej na temat mikrofalowych wzmacniaczy mocy typu Doherty. Zaprezentowano projekt wysokosprawnego trójdrożnego wzmacniacza typu Doherty z tranzystorami Wolfspeed CG2H40010. Ponadto przedstawiono unikalną konstrukcję trójdrożnego dzielnika mocy, która umożliwiła zaprojektowanie trójdrożnego wzmacniacza typu Doherty w konfiguracji odwróconej. Przedstawiony wzmacniacz charakteryzuje się zwartą konstrukcją, która nie wymaga dodatkowych linii fazowych, co umożliwia poszerzenie pasma pracy. Układ pracuje w paśmie telekomunikacyjnym 3,4 – 3,8 GHz i osiąga w nasyceniu 46 W mocy przy sprawności drenowej 75%. Dla sygnałów o mocy wyjściowej niższej o 10 dB względem nasycenia wzmacniacz uzyskuje sprawność 53%.

5

MTCA.4 : modular measurement and control system with sub-nanosecond time synchronization and support for RF applications

Kasprowicz G.

International Journal of Electronics and Telecommunications

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2016

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Vol. 62, No. 3

289--292

EN

The Micro TCA platform [1] is rapidly developing modular technology for measurement and control systems. There are available versions for laboratories, military and aviation. The newest release of the standard (MTCA.4) supports high frequency RF applications like particle accelerators, radio, telecom and radar. The PERG group together with partners from Europe and Poland takes active part in development process, i.e. implementation of sub-ns [2] synchronization, event and RF distribution system over fibre networks. It enhances significantly capabilities of MTCA platform in distributed measurement systems (i.e. passive radars) and enables fully deterministic operation of hard real time control systems.

6

MTCA.4 : modułowy system kontrolno-pomiarowy z sub-nanosekundową synchronizacją czasu oraz wsparciem dla technologii RF

Kasprowicz G.

Elektronika : konstrukcje, technologie, zastosowania

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2016

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Vol. 57, nr 2

10--14

PL

Platforma MicroTCA jest obecnie najszybciej rozwijającą się technologią modułowych systemów kontrolno – pomiarowych. Dostępne są wersje laboratoryjne, wojskowe i dla lotnictwa. Najnowsza wersja (MTCA.4) zapewnia wsparcie dla aplikacji wysokich częstotliwości, takie jak akceleratory cząstek, urządzenia radiokomunikacyjne i radarowe. Grupa badawcza PERG z Instytutu Systemów Elektronicznych wraz z partnerami z Europy i Polski bierze aktywny udział w tych pracach, m. in. w implementacji sub-nanosekundowego systemu synchronizacji czasu, dystrybucji zdarzeń i wysokich częstotliwości z użyciem technologii światłowodowej. Pozwala to znacznie zwiększyć możliwości platformy MTCA w aplikacjach rozproszonych systemów pomiarowych (np. technologie radarów pasywnych i aktywnych) oraz zapewnić w pełni deterministyczną pracę rozproszonych systemów sterowania (ang. hard real time).

EN

The MicroTCA platform is rapidly developing modular technology for measurement and control systems. There are available versions for laboratories, military and aviation. The newest release of the standard (MTCA.4) supports high frequency RF applications like particle accelerators, radio, telecom and radar. The PERG group together with partners from Europe and Poland takes active part in development process, i.e. implementation of sub-ns synchronization, event and RF distribution system over fibre networks. It enhances significantly capabilities of MTCA platform in distributed measurement systems (i.e. passive radars) and enables fully deterministic operation of hard real time control systems.

7

RF energy harvesting for low power electronic devices: student project

Mihaylov K

International Journal of Microelectronics and Computer Science

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2014

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Vol. 5, nr 1

41--45

EN

Different methods for RF energy harvesting from radio transmitters with working frequency of up to 108 MHz are examined. Experiments are conducted especially with the LW transmitter near Vakarel village (261 kHz) (Soﬁa, Bulgaria) and the transmitter of the National Radio “HristoBotev” at radio- tower “Kopitoto” (92. 9 MHz) (Sofia, Bulgaria). Partial success is achieved with electrically small loop antenna resonated at 261 kHz.

8

Synchronizowana sieć pomiarowa

Kubiak Z.

Studia Informatica

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2013

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Vol. 34, nr 3

117--129

PL

W artykule przedstawiono opracowanie protokołu SMN (ang. Synchronized Measurement Network) oraz uwarunkowania, wynikające ze specyfiki wybranych radiowych układów nadawczo-odbiorczych. Prezentowane rozwiązanie należy do bezprzewodowych sieci sensorowych (ang. WSN – Wireless Sensor Networks). Protokół SMN jest przeznaczony do synchronizowanej, bezprzewodowej realizacji pomiarów rozproszonych. Omawiana sieć zapewnia możliwość energooszczędnej pracy jej węzłów oraz spełnia warunki bezpieczeństwa transmisji.

EN

This paper presents the development of SMN protocol (Synchronized Measurement Network) and conditions resulting from the specificity of selected radio transceiver systems. This solution is a wireless sensor network (WSN – Wireless Sensor Networks). SMN protocol is designed for execution of synchronized, distributed wireless measurement. The presented network provides the possibility of energy-saving work of its nodes and meets the security conditions of transmission.

9

Research on Damage Mechanism of SCB Initiators under RF

Chen F., Zhou B., Qin Z, Shen R.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 11a

188-190

EN

In order to elucidate the response characteristic of semiconductor bridge(SCB) initiators under radio frequency(RF), RF measurement system was used to test the RF sensitivity of SCBs, after that the energy stored in a 22?F was used to activate the SCB. It is inferred from the results of Bruceton-method firing experiment that RF energy does not damage the SCB chip, but can lead to the accidental ignition of SCB initiators or change the color of normal lead styphnate(NLS). RF can also passivate SCB significantly and the all-fire voltage increases from 6.71V to 7.72V. The experimental data of X-ray photoelectron spectroscopy(XPS) analysis, directly indicated that heat generated by RF changes the valence of Pb in NLS from +2 to +4. The decomposition of NLS is responsible for the loss in sensitivity of SCBs. The research results provide a theoretical guidance for the electromagnetic compatibility(EMC) design of SCB initiators.

PL

W artykule opisano badanie oddziaływania sygnałów częstotliwości radiowej (ang. Radio Frequency) na zapalniki zbudowane z mostka półprzewodnikowego. Przedstawiono omówienie teoretyczne oraz wyniki badań eksperymentalnych.

10

27 dBm Microwave Amplifiers with Adaptive Matching Networks

Rosolowski D., Wojtasiak W., Gryglewski D.

International Journal of Electronics and Telecommunications

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2011

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Vol. 57, No. 1

103-108

EN

The paper describes adaptive amplifier design with varactors and pin diodes as regulators of matching networks. As examples the two amplifiers with SHF-0189 HFET transistor and different matching sections were designed and manufactured. The output power level of 27 dBm and gain higher than 13 dB within L and S-band have been achieved. The amplifier design methodology is based on the small-signal approach and DC characteristics of transistors and regulators. Amplifier adaptivity allows us to remotely control the chosen parameters such as: frequency range, output power level, gain and etc.

11

Radio programowalne

Pawłowski R., Dąbrowski A., Skrzypek P., Roszak P., Pałejko A., Walenciak T., Mor M.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 5

89-93

PL

W niniejszym artykule zaproponowano kompletną architekturę radia programowalnego. Omówiono architekturę opracowanego systemu wraz z wymaganiami stawianymi każdemu z bloków przetwarzających sygnał. Przedstawiono prototypową implementacje, jej specyfikację, uwagi projektowe oraz aplikację kliencką

EN

In this paper, a complete architecture of the software defined radio receiver is proposed. First, a precise definition and the discussion of the problem is given. Next, an outline of the system topology is proposed, together with the requirements for each component of the system. Finally, a custom implementation is presented, including specifications, design considerations, and client application.

12

EuCARD 2010 Accelerator Technology in Europe

Romaniuk R. S.

International Journal of Electronics and Telecommunications

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2010

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Vol. 56, No. 4

485-488

EN

Accelerators are basic tools of the experimental physics of elementary particles, nuclear physics, light sources of the fourth generation. They are also used in myriad other applications in research, industry and medicine. For example, there are intensely developed transmutation techniques for nuclear waste from nuclear power and atomic industries. The European Union invests in the development of accelerator infrastructures inside the framework programs to build the European Research Area. The aim is to build new infrastructure, develop the existing, and generally make the infrastructure available to competent users. The paper summarizes the first year of activities of the EU FP7 Project Capacities EuCARD - European Coordination of Accelerator R&D. Several teams from this country participate actively in this project. The contribution from Polish research teams concerns: photonic and electronic measurement - control systems, RF-gun co-design, thin-film superconducting technology, superconducting transport infrastructures, photon and particle beam measurements and control.

13

EuCARD 2010 : technika akceleratorowa w Europie

Romaniuk R. S.

Elektronika : konstrukcje, technologie, zastosowania

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2010

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Vol. 51, nr 8

178-179

PL

Akceleratory są podstawowymi narzędziami eksperymentalnej fizyki cząstek elementarnych, fizyki jądrowej, źródeł światła czwartej generacji. Na przykład intensywnie rozwijają się techniki transmutacji odpadów promieniotwórczych z przemysłu energetyki jądrowej i atomistyki. Unia Europejska inwestuje w rozwój infrastruktury akceleratorowej w ramach programów ramowych utworzenia Europejskiego Obszaru Badawczego. Celem jest rozwój nowej, udoskonalenie istniejącej, oraz udostępnienie infrastruktury badawczej kompetentnym użytkownikom. Artykuł podsumowuje pierwszy rok działalności Projektu UE FP7 Capacities, EuCARD (2009-2013) - European Coordination for Accelerator R&D. W projekcie uczestniczą aktywnie partnerzy krajowi.

EN

Accelerators are basic tools of the experimental physics of elementary particles, nuclear physics, light sources of the fourth generation. They are also used in myriad other applications in research, industry and medicine. For example, there are intensely developed transmutation techniques for nuclear waste from nuclear power and atomic industries. The European Union invests in the development of accelerator infrastructures inside the framework programs to build the European Research Area. The aim is to build new infrastructure, develop the existing, and generally make the infrastructure available to competent users. The paper summarizes the first year of activities of the EU FP7 Project Capacities EuCARD - European Coordination of Accelerator R&D Several teams from this country participate actively in this project.

14

A Behavioral Model for Sigma Delta Fractional PLL and Applications to Circuit Dimensioning

Duarte R., Fernandes J. R.

Electronics and Telecommunications Quarterly

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2009

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Vol. 55, No 4

563-575

EN

This paper presents an accurate high level model for the design of sigma-delta fractional Phase locked loop (PLL) architectures. High level models provide simulation speedups of about two orders of magnitude when compared to transistor level simulation. When compared to other models presented in the literature the proposed model has the advantage of having the frequency instead of phase as the output of the VCO. This approach greatly simplifies the implementation of the PLL blocks and results in an increase of the overall model performance. Several nonlinear phenomenons's such as cycle slipping, spurious signals and phase noise are also accurately modelled. Finally, this paper combines genetic algorithms with the proposed behavioral model to optimize the PLL parameters and reduce the impact of the sigma-delta phase noise.

15

Charakteryzacja właściwości mechanicznych warstw węglowych na UHDPE

Batory D., Grabarczyk J., Kaczorowski W.

Engineering of Biomaterials

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2008

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Vol. 11, no. 76

24--27

PL

Polietylen dużej gęstości (UHDPE - Ultra High Density Polyethylene) jest jednym z najpopularniejszych polimerów stosowanych w medycynie. Z materiałem tym bardzo często możemy się spotkać w konstrukcjach stawów biodrowych czy kolanowych, gdzie nie bez znaczenia są ich odpowiednie właściwości mechaniczne. W zastosowaniach, gdzie wymagany jest niski współczynnik tarcia i wysoka odporność na zużycie, warstwy węglowe wydają się być najlepszym rozwiązaniem. Dodatkowo oprócz pozytywnego wpływu warstw węglowych na właściwości mechaniczne, powłoki te wpływają na poprawę biozgodności pokrywanych materiałów. Celem przeprowadzonych badań była charakteryzacja mechanicznych właściwości warstw węglowych wytworzonych na podłożu UHDPE z użyciem różnych metod CVD i PVD. Najistotniejszym zagadaniem było zbadanie zależności pomiędzy współczynnikiem tarcia i odpornością na zużycie a zastosowaną metodą i parametrami wytwarzania warstw. Badania trybologiczne zostały wykonane metodą pin-on-disc. Uzyskane wyniki wskazują na możliwości wykorzystania warstw węglowych na podłożu polimeru UHDPE jako powłok poprawiających odporność na zużycie oraz zmniejszających współczynnik tarcia.

EN

Ultra High Density Polyethylene (UHDPE) is one of the most popular polymer materials widely used in medicine. Very often UHDPE it utilised in hip joint and knee constructions, were its perfect mechanical properties are very important. Carbon-based layers seem to be very attractive material for many applications where low friction coefficient and high wear resistant are needed. Beside of positive mechanical properties these layers improve biocompatibility of covered surfaces. The aim of the study was the characterization of mechanical properties of different types of carbon-based layers manufactured with use of CVD and PVD methods on UHDPE. Precisely the purpose was to find the correlation between obtained friction and wear parameters and applied method and the deposition parameters. The friction coefficient and wear resistance were measured by the pin-on-disc method. As a result of the investigations it was noticed that hard carbon layers deposited on Ultra High Density Polyethylene’s surface noticeably improve its wear resistance and ensure very low friction coefficient.