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A model of liquid film breakdown formed due to impingement of a two-phase jet on a horizontal surface
PublicationThe present work aims to provide an explanation to the phenomenon of breakdown of the thin liquid film created by impinging two-phase, liquid-gas jet. Existing in the literature models describe merely thebreakdown of single phase liquid films. The model presented here is based on examination of mass and energy equations under the applied criterion of the minimum of total energy. That allows to determinethe minimum thickness of...
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Study on effective front region thickness of PCM in thermal energy storage using a novel semi-theoretical model
PublicationThermal energy storage in mobile applications, particularly battery of electric vehicles, is currently gaining a lot of importance. In this paper, a semi-theoretical time-dependent mathematical model of the phase change in a double shell thermal energy storage module has been developed where the inner tube is a heat exchange surface. An effective front region thickness for the melting and solidification process has been studied....
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Minichannel and minigap classification criteria based on the aspect ratio of the minigeometry: A numerical study
PublicationA detailed numerical investigation has been carried out to analyze the diabatic flow distribution and velocity profile in 18 minigeometries with various aspect ratios for V-type and I-type flow configurations (for 36 cases) assuming ethanol as a working fluid. The aim of the study is to distinguish the value of the aspect ratio for which the flow in minigeometry starts to be two-dimensional (minigap). Cases with a constant Reynolds...
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Theoretical consideration of free convective heat transfer from a round isothermal plate slightly inclined from the vertical
PublicationA semi-analytical solution of simplified Navier-Stokes and Fourier-Kirchhoff equations describing free convective heat transfer from a round isothermal surface slightly inclined from the vertical is presented. The solution is based on the assumption, typical for natural convection, that the velocity component normal to the surface is negligibly small in comparison to the tangential one. Next we neglect the nonlinear inertia force...
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Karolina Lademann Mgr
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Anna Brillowska-Dąbrowska dr hab. inż.
PeopleAnna Brillowska-Dąbrowska, born in 1971 in Gdańsk, Poland, graduated in 1996 in Biotechnology from the Faculty of Chemistry, Gdańsk University of Technology (GUT). In 2001 she got her PhD, in 2013 became a DSc (habilitation). She was employed in 2004 as a researcher in Statens Serum Institut in Denmark. Currently she is an Associate Professor (adiunkt) in the Department of Molecular Biotechnology and Microbiology and Vice-dean...
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Double-diffusive natural convection energy transfer in magnetically influenced Casson fluid flow in trapezoidal enclosure with fillets
PublicationThe prime motive of this disquisition is to deal with mathematical analysis of natural convection energy transport driven by combined buoyancy effects of thermal and solutal diffusion in a trapezoidal enclosure. Casson fluid rheological constitutive model depicting attributes of viscoelastic liquids is envisioned. The influence of the inclined magnetic field governed by Lorentz field law is also considered. To raise the essence...
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Development and tuning of irregular divide-and-conquer applications in DAMPVM/DAC
PublicationThis work presents implementations and tuning experiences with parallel irregular applications developed using the object oriented framework DAM-PVM/DAC. It is implemented on top of DAMPVM and provides automatic partitioning of irregular divide-and-conquer (DAC) applications at runtime and dynamic mapping to processors taking into account their speeds and even loads by other user processes. New implementations of parallel applications...
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SSFR Test of Synchronous Machine for Different Saturation Levels using Finite-Element Method
PublicationIn this paper the StandStill Frequency Response characteristics (SSFR) of saturated synchronous generator (SG) have been calculated using Finite Element Method (FEM) analysis. In order to validate proposed approach for unsaturated conditions FEM simulation from Flux2D software has been compared with the measurements performed on the 10 kVA, 4- poles synchronous machine ELMOR GCe64a of salient rotor construction, equipped with a...
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Natural convective heat transfer from isothermalconic
PublicationTheoretical considerations on convective heat transfer from isothermal upward conicalsurfaces have been presented. The physical model of this phenomenon consists of an isothermalcone of inclination angle (φ) between the cone generating line (X) and the radius (R) of the cone base. The angle is a parameter of conical surface which varied from (φ = 0−circular horizontal plate) to (φ = π/2—vertical cylinder) . Onthe basis of Navier–Stokes...
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Numerical model for thin liquid film with evaporation and condensation on solid surfaces in systems with conjugated heat transfer
PublicationCondensation and evaporation processes from wetted surfaces are of utmost importance in many technological or industrial applications. In many devices such as home-appliances and air conditioning systems just to name a few, condensation and evaporation processes greatly impact their performance and energy efficiency; The physics of these processes is quite complex, involving conjugate heat transfer among solid–liquid film-gaseous...
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Wieloobszarowa regulacja systemu turbogeneratora elektrowni jądrowej =Multiregional control of nuclear power plant turbogenerator system
PublicationW artykule przedstawiono propozycję zaawansowanej struktury sterowania układem turbogeneratora w szerokim zakresie zmian zapotrzebowania na moc czynną. Dla potrzeb syntezy tej struktury wykorzystano nieliniowe, dynamiczne modele turbiny parowej i generatora synchronicznego współpracującego z systemem elektroenergetycznym. Zaproponowane algorytmy sterowania oparte są odpowiednio o wieloobszarowe regulatory rozmyte, z lokalnymi regulatorami...
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Advanced Control Structures of Turbo Generator System of Nuclear Power Plant
PublicationIn the paper a synthesis of advanced control structures of turbine and synchronous generator for nuclear power plant working under changing operating conditions (supplied power level) is presented. It is based on the nonlinear models of the steam turbine and synchronous generator cooperating with the power system. Considered control structure consists of multi-regional fuzzy control systems with local linear controllers, including...
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Comparison of tuning procedures based on evolutionary algorithm for multi-region fuzzy-logic PID controller for non-linear plant
PublicationThe paper presents a comparison of tuning procedures for a multi-region fuzzy-logic controller used for nonlinear process control. This controller is composed of local PID controllers and fuzzy-logic mechanism that aggregates local control signals. Three off-line tuning procedures are presented. The first one focuses on separate tuning of local PID controllers gains in the case when the parameters of membership functions of fuzzy-logic...
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Advanced Control Structures of Turbo Generator System of Nuclear Power Plant
PublicationIn the paper a synthesis of advanced control structures of turbine and synchronous generator for nuclear power plant working under changing operating conditions (supplied power level) is presented. It is based on the nonlinear models of the steam turbine and synchronous generator cooperating with the power system. Considered control structure consists of multi-regional fuzzy control systems with local linear controllers, including...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublicationThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublicationThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Data recorded for the purpose of the 3D sound intensity visualization around the organ pipe (des sound)
Open Research DataThe set contains data recorded using the Cartesian robot and multichannel acoustic vector sensor (from Microflown) for the purpose of the 3D sound intensity visualization of radiated acoustic energy around the organ pipe.
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Identification and non-integer order modelling of synchronous machines operating as generator
PublicationThis paper presents an original mathematical model of a synchronous generator using derivatives of fractional order. In contrast to classical models composed of a large number of R-L ladders, it comprises half-order impedances, which enable the accurate description of the electromagnetic induction phenomena in a wide frequency range, while minimizing the order and number of model parameters. The proposed model takes into account...
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Time domain model of the resonance-based electromagnetic pulses emission system
PublicationIn the literature, the emission properties of the electromagnetic field pulse systems based on high voltage antennas (HVR) have been widely described. In order to increase the emission efficiency by extending duration and increasing amplitude of the impulse it is possible to use a resonance system tuned to the parameters of the signal shaped in the pulse forming circuit. The synthesis of a time-domain simulation model of a complex...
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Path Loss Modelling in the Untypical Outdoor Propagation Environments
PublicationIn the paper three ways of path loss modelling in the untypical outdoor environments are presented. The exemplary untypical outdoor environment is analyzed. The investigated environment is characterized, and the measurement campaign are shortly described. The following models have been analyzed: the COST231 Walfisch-Ikegami model, the modified COST231Walfisch-Ikegami model tuned on the basis of empirical data, and the empirical...
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Inverse heat transfer problem solution of sounding rocket using moving window optimization
PublicationAn Inverse Heat Transfer Problem is solved for a sounding rocket module given its geometry and measured temperature profile. The solution is obtained via moving window optimization, a technique for solving inverse dynamics. An analysis is performed to modify the method to avoid oscillatory behavior of the resulting heat flux profile. The method parameters are tuned in relation to characteristic phases of the flight. Results are...
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Response features for fast EM-driven design of miniaturized impedance matching transformers
PublicationA framework for low-cost EM-driven design optimization of compact impedance matching transformers is presented. Our technique is based on a bottom-up design where design requirements for the transformer circuit are translated into specifications for its building blocks. These elementary cells are optimized using response features. Subsequently, the entire circuit is fine-tuned using local response surface approximation models and...
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Bartłomiej Luks dr
PeopleI'm a snow researcher, working in the Arctic for almost 20 years. I've started as a field assistant on a geological expedition to Bellsund (Spitsbergen), then did my masters on soil pollution in the vicinity of Polish Polar Station Hornsund and PhD on dynamics of snowpack in the SW Spitsbergen. Since 2013 I'm an Assistant Professor at the Department of Polar and Marine Research IG PAS in Warsaw. My main research interests are the...
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Ionization and ionic fragmentation of tetrahydrofuran molecules by electron collisions
PublicationElectron impact ionization and ionic fragmentation of tetrahydrofuran molecules in the gas phase were studied in the energy range from ionization threshold up to 150 eV using the technique of mass spectrometry. The cation mass spectra, ionization and ionic fragmentation efficiencies were measured over this energy range. Well-resolved mass peaks were detected in the mass range 10-72 amu and assigned to corresponding ionic molecular...
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Enhancement of self-trapped excitons and near-infrared emission in Bi3+/Er3+ co-doped Cs2Ag0.4Na0.6InCl6 double perovskite
Open Research DataErbium (Er) complexes are used as optical gain materials for signal generation in the telecom C-band at 1540 nm, but they need a sensitizer to enhance absorption. Na+ substitution for Ag+ and Bi3+ doping at the In3+ site is a possible strategy to enhance the broadband emission of Cs2AgInCl6, which could be used as a sensitizer for energy transfer to...
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Analytical data on molecular umbrella: cispentacin and molecular umbrella: fluorescent probe conjugates
Open Research DataAnalytical data (NMR, MS, FTIR) for nine conjugates of molecular umbrella with cispentacin, Lys(Mca) or Nap-NH2. The conjugates have been rationally designed as potential antifungal agents. 1H NMR and 13C NMR spectra were obtained at 500 MHz Varian Unity Plus spectrometer and the deuterated solvents were used as internal locks. High-resolution mass...
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Adaptive filtering approach to dynamic weighing: a checkweigher case study
PublicationDynamic weighing, i.e., weighing of objects in motion, with out stopping them on the weighing platform, allows one to increase the rate of operation of automatic weighing systems used in industrial production processes without compromising their accuracy. The paper extends and compares two approaches to dynamic weighing, based on system identification and variable-bandwidth filtering, respectively. Experiments, carried on a conveyor...
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Reduction of parasitic pitch variations in archival musical recordings
PublicationA new method for reducing parasitic pitch variations in archival audio recordings is presented. The method is intended for analyzing movie soundtracks recorded in optical films. It utilizes image processing for calculating and reducing effects of tape shrinkage being one of the main reasons for parasitic pitch variations in audio accompanying moving images. As long as the film tape characteristics are known the new method can be...
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Performance Analysis of Convolutional Neural Networks on Embedded Systems
PublicationMachine learning is no longer confined to cloud and high-end server systems and has been successfully deployed on devices that are part of Internet of Things. This paper presents the analysis of performance of convolutional neural networks deployed on an ARM microcontroller. Inference time is measured for different core frequencies, with and without DSP instructions and disabled access to cache. Networks use both real-valued and...
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Nanodiamonds Doped with Manganese for Applications in Magnetic Resonance Imaging
PublicationNanodiamonds (NDs) are emerging with great potential in biomedical applications like biomarking through fluorescence and magnetic resonance imaging (MRI), targeted drug delivery, and cancer therapy. The magnetic and optical properties of NDs could be tuned by selective doping. Therefore, we report multifunctional manganese-incorporated NDs (Mn-NDs) fabricated by Mn ion implantation. The fluorescent properties of Mn-NDs were tuned...
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Designing a ship course controller by applying the adaptivebackstepping method
PublicationThe article discusses the problem of designing a proper and efficient adaptive course-keeping control system for a seagoingship based on the adaptive backstepping method. The proposed controller in the design stage takes into account thedynamic properties of the steering gear and the full nonlinear static maneuvering characteristic. The adjustable parametersof the achieved nonlinear control structure were tuned up by using the...
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Thermal behaviour of vanadium xerogel powder under oxidizing atmosphere
Open Research DataThe DataSet contains the results of the thermal behavior of the vanadium xerogel powder. The information about xerogel powder synthesis is described in the Journal of Nanomaterials.
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Thermal behaviour of vanadium xerogel powder under argon atmosphere
Open Research DataThe DataSet contains the results of the thermal behavior of the vanadium xerogel powder. The information about xerogel powder synthesis is described in the Journal of Nanomaterials.
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Thermal behavior of (NH4)V4O10xH2O
Open Research DataThe DataSet contains the results of the thermal behavior of the (NH4)V4O10xH2O obtained by the hydrothermal method using different precursors: microstructured (commercially available) or nanostructured. The information about samples synthesis is described in the Materials.
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Modeling by finite element methods of impact of erosion on frequency of normal modes of L-0 blade
PublicationAfter some time of exploitation steam turbine rotors blades in energetic industry they are being eroded and also their frequency of normal modes is changed. Those changes can cause to unwanted shift of blades normal mode frequencies. It is necessary to find quick method of rating changes of frequency in connection of mass loss due erosion. The evaluation of this dependence was made by finite element modeling method using HyperWorks...
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Pounding mitigation of a short-span cable-stayed bridge using a new hybrid passive control system
PublicationThis paper investigates the effectiveness of a new hybrid passive control system on the seismic response of an existing steel cable-stayed bridge considering the pounding effect. The proposed hybrid passive control system comprises a seismic isolator and a metallic damper. The bridge is located in a high seismic zone and has suffered several damages including the earthquake-induced pounding damage during the 1988 earthquake....
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Half-Order Modeling of Saturated Synchronous Machine
PublicationNoninteger order systems are used to model diffusion in conductive parts of electrical machines as they lead to more compact and knowledge models but also to improve their precision. In this paper a linear half-order impedance model of a ferromagnetic sheet deduced from the diffusion of magnetic field is briefly introduced. Then, from physical considerations and finite elements simulation, the nonlinear half-order impedance model...
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Cross sections for ionization and ionic fragmentation of pyrimidine molecules by electron collisions
PublicationThe electron impact mass spectroscopy and the total ion collection measurements were used to investigate the ionization and ionic fragmentation of the pyrimidine, C4H4N2, molecules in the gasphase. The cation mass spectra were measured in the 10−85 amu range and the observed mass peaks assigned to corresponding ionic fragments. The most abundant cation in the mass spectra is the parent cation, C4H4N+2, at 80 amu. The appearance...
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Dehydrogenation in electron-induced dissociative ionization of pyridine molecule
PublicationThe electron-impact dissociative ionization of pyridine has been investigated using mass spectrometry. Thirty-two well-resolved mass peaks have been identified in the cation mass spectra and assigned to the most likely ionic molecular fragments. The new sixteen ionic fragments' appearance energies have been determined, and sixteen others remeasured. The total cross-section for electron-impact ionization of pyridine has been measured...
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Effect of Thermal Treatment and Erosion Aggressiveness on Resistance of S235JR Steel to Cavitation and Slurry
PublicationS235JR steel is used in many applications, but its resistance to the erosion processes has been poorly studied. To investigate this resistance, cavitation, and slurry erosion tests were conducted. These tests were carried out at different erosion intensities, i.e., different flow rates in the cavitation tunnel with a system of barricades and different rotational speeds in the slurry pot. The steel was tested as-received and after...
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Personal adaptive tuning of mobile computer audio
PublicationAn integrated methodology for enhancing audio quality in mobile computers is presented. The key features are adaptation of the characteristics of the acoustic track to the changing conditions and to the user's individual preferences. Original signal processing algorithms are introduced, which concern: linearization of frequency response, dialogue intelligibility enhancement and dynamics processing tuned up to the user's preferences....
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Thermal behaviour of NH4VO3 microcasketoids
Open Research DataThe DataSet contains the results of the thermal behavior of the ammonium metavanadate microcasketoids under argon and nitrogen atmosphere. Thermogravimetric analysis (TG) was carried out under argon or nitrogen atmosphere from 40C to 560C (with a heating rate of 10 C/min) using Netzsch STA 449 F1. The thermal behavior was also studied with mass spectrum...
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Thermal behaviour of NH4VO3 nanoflowers
Open Research DataThe DataSet contains the results of the thermal behavior of the ammonium metavanadate nanoflowers under argon and nitrogen atmosphere. Thermogravimetric analysis (TG) was carried out under argon or nitrogen atmosphere from 40C to 560C (with a heating rate of 10 C/min) using Netzsch STA 449 F1. The thermal behavior was also studied with mass spectrum...
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Thermal behaviour of NH4VO3 elongated microcrystals
Open Research DataThe DataSet contains the results of the thermal behavior of the ammonium metavanadate elongated microcrystals under argon and nitrogen atmosphere. Thermogravimetric analysis (TG) was carried out under argon or nitrogen atmosphere from 40C to 560C (with a heating rate of 10 C/min) using Netzsch STA 449 F1. The thermal behavior was also studied with mass...
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Thermal behaviour of commercial avaible NH4VO3
Open Research DataThe DataSet contains the results of the thermal behavior of the commercially available ammonium metavanadate (CAS 7803-55-6) under argon and nitrogen atmosphere. Thermogravimetric analysis (TG) was carried out under argon or nitrogen atmosphere from 40C to 560C (with a heating rate of 10 C/min) using Netzsch STA 449 F1. The thermal behavior was also...
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Thermal behaviour of NH4VO3 microflowers
Open Research DataThe DataSet contains the results of the thermal behavior of the ammonium metavanadate microflowers under argon and nitrogen atmosphere. Thermogravimetric analysis (TG) was carried out under argon or nitrogen atmosphere from 40C to 560C (with a heating rate of 10 C/min) using Netzsch STA 449 F1. The thermal behavior was also studied with mass spectrum...
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Thermal behaviour of ammonium vanadate nanocrystals
Open Research DataThe DataSet contains the thermal behavior of the ammonium vanadate nanostructures obtained by the hydrothermal method with different conditions. Thermogravimetric analysis (TG) was carried out under an argon atmosphere from 40C to 560C (with a heating rate of 10 C/min) using Netzsch STA 449 F1. The thermal behavior was also studied with mass spectrum...
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Recent Applications of 1D GC-MS and 2D GC-MS in Foodomics Studies
PublicationGas chromatography coupled with mass spectrometry and food chemistry have been tightly linked since the 1960s. This setup is also an integral part of the omics studies when it comes to low mass metabolites. Therefore, the marriage of GC-MS and foodomics is obvious. Two-dimensional gas chromatography coupled with mass spectrometry fits perfectly within the latest trends in foodomics, since it is tailored for holistic food analysis....
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Analiza sterowania ułamkowego PIλDμ mocą reaktora jądrowego
PublicationW artykule przedstawiono syntezę regulatora PIλDμ niecałkowitego rzędu dla potrzeb sterowania mocą reaktora jądrowego lekko wodnego określanego, jako typu PWR (Pressurized Water Reactor). W tym celu wykorzystano nieliniowy model matematyczny reaktora PWR o parametrach skupionych obejmujący procesy generacji i wymiany ciepła oraz termicznych efektów reaktywnościowych. Nastawy regulatora PIλDμ niecałkowitego rzędu dobrano w sposób...