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Search results for: EXTERNAL ELECTRIC VOLTAGE
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Activity coordination of capacitor banks and power transformer controllers in order to reduce power losses in the MV grid
PublicationOne of the main issues related to the optimization of the MV (middle voltage) network is to reduce losses of active and reactive power. Lower losses of active and reactive power give not only economic advantage, but also improvement of energy quality. The object of regulation that can be used for these purposes are transformer with On-Load Tap Changer and capacitor's banks. This paper presents results of analysis of the possibility...
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EMI attenuation in a DC-DC buck converter using GaN HEMT
PublicationA dc-dc buck converter using gallium nitride (GaN) high electron mobility transistors (HEMT) is experimentally investigated at the discontinuous current mode (DCM) and at the triangular current mode (TCM) operation. The paper objective is to specify the power conversion efficiency and attenuation of common mode (CM) and differential mode (DM) noise voltage, measured at the line impedance stabilization network (LISN) for compared...
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BET specific surface area measurements of bismuth oxide (Bi2O3) and gadolinium oxide (Gd2O3) structures
Open Research DataThe BET specific surface area was measured using an N2 adsorption/desorption isotherm (Micromeritics ASAP 2460, Norcross, GA, USA).
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Inventory of the historic door woodwork at Matejki Street in Gdańsk-Wrzeszcz district, stage from 2014.
Open Research DataThe data presents photographic documentation of the historic door woodwork in apartment houses at Matejki Street, number 2,7, 8, 9, as a part of inventory works of the external door woodwork at the turn of the 19th and 20th centuries in Gdańsk-Wrzeszcz district. The inventory was a conducted within the historical research of the Gdańsk-Wrzeszcz district...
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Instantaneous impedance monitoring of synergistic effect between cavitation erosion and corrosion processes
PublicationThe most common method of determination of cavitation erosion resistance as well as the magnitude of erosion-corrosion synergistic interaction is based on the weight loss measurements. Nondestructive characterization of installations elements is in most cases impossible to perform. Also, such a measurement does not include local types of failure or alteration of operating conditions. There is an urge to elaborate a method for monitoring...
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Electrical characteristics simulation of top-gated graphene field-effect transistor (GFET) with 10 μm x 10 μm graphene channel
Open Research DataThe presented data set is part of the research on graphene field-effect transistor (GFET) modelling. The calculations were performed with the use of GFET Tool program (https://nanohub.org/resources/gfettool DOI: 10.4231/D3QF8JK5T), which enabled simulation of the drain current (Id) vs. drain voltage (Vd) characteristics for different gate voltages (Vg)...
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Electrical characteristics simulation of top-gated graphene field-effect transistor (GFET) with 10 μm x 3 μm graphene channel
Open Research DataThe presented data set is part of the research on graphene field-effect transistor (GFET) modelling. The calculations were performed with the use of GFET Tool program (https://nanohub.org/resources/gfettool DOI: 10.4231/D3QF8JK5T), which enabled simulation of the drain current (Id) vs. drain voltage (Vd) characteristics for different gate voltages (Vg)...
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Topological Model of an Electromagnetic Environment Inside a Ship for Electromagnetic Compatibility (EMC) Analysis
PublicationThe mutual electromagnetic (EM) interactions between electrical and electronic devices in a segmented space, such as a ship's environment, ared described. Firstly, the topological structure of a ship's segmented internal environment, which consists of many electrical screening walls (shielding planes), is presented. Then, taking into account the ship's topological structure, a general description of the EM disturbance distribution,...
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ADT in mammography
PublicationWe discuss limitations of the known methods of IR imaging in diagnostics of breast cancer. In conclusion we show that for practical reasons one requires new approaches because the known methods based on simple observation of external temperature distribution are not fully effective. Even advanced pattern recognition could not help too much for static images. We ask the question: may active dynamic thermography, known in nondestructive...
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Motor Cable Influence on the Conducted EMI Emission of the Converter Fed AC Motor Drive. - Vol. 1
PublicationInvestigation of conducted electromagnetic interference in AC motor drives fed by pulse width modulated voltage converters requires considering parasitic capacitances in converters, motor windings and feeding cables to be taken into account. Motor voltage transients and related conducted electromagnetic emission are significantly correlated with resonance effects occurring in load circuits. The levels of intensity of these phenomena...
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The adaptive backstepping control of PMSM supplied by current source inverter for the field weakening region
PublicationThe sensorless control system of permanent magnet synchronous motor PMSM supplied by current source inverter for field weakening operation is presented in this paper. The adaptive backstepping control system and the backstepping speed observer are presented. The control system is based on multi-scalar variables. The control variables are: dc-link voltage and the output current vector pulsation. The control system was named voltage...
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Evaluation of electrical parameters of traction supply system for complex railway traffic conditions, using simulation methods
PublicationDevelopment of electrified transport systems, railways modernization, expansion of urban transport networks, purchases of modern rolling stock causes that updating of electric traction supply system is necessary. This chapter presents an effective method for electrical parameters of traction supply system evaluation, using simulation methods.
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Installation of Compensators in the Power System Transmission Grid
PublicationThe article discusses issues of reactive power compensation in transmission grids, with particular focus on the selection of compensator locations and basic parameters. Attention was focused on modern power electronics systems that ensure full automatic compensator adjustment to voltage or power criteria.
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A nine-input 1.25 mW, 34 ns CMOS analog median filter for image processing in real time
PublicationIn this paper an analog voltage-mode median filter, which operates on a 3 × 3 kernel is presented. The filter is implemented in a 0.35 μm CMOS technology. The proposed solution is based on voltage comparators and a bubble sort configuration. As a result, a fast (34 ns) time response with low power consumption (1.25 mW for 3.3 V) is achieved. The key advantage of the configuration is relatively high accuracy of signal processing,...
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Interline power flow controller - properties and control strategy in dynamic states
PublicationHigh-power electronic converter topologies, in such forms as Unified Power Flow Controllers (UPFC), Static Compensators (STATCOM) and Interline Power Flow Controllers (IPFC), have been used to enhance and optimize the use of transmission facilities, under the concept of a flexible ac transmission system (FACTS). In Europe, the anticipated proliferation of distributed-generation (DG) in the near future, driven by governmental initiatives...
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Digital Processing of Frequency–Pulse Signal in Measurement System
PublicationThe work presents the issue of the use of multichannel measurement systems of sensors processing input value to impulse signal frequency. The frequency impulse signal obtained from such sensors is often required to be processed at the same time with a voltage signal which is obtained from other sensors used in the same measurement system. In such case, it is usually necessary to sample the output signals from all sensors in the...
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The conducted immunity test of a power supply unit in accordance with EMC standards
Open Research DataThe dataset presents a result of measurements that are a part of immunity tests to conducted disturbances, induced by radio-frequency fields. The immunity tests were carried out on the mains cable of the DF1723003TC NDN power supply. Tests of immunity of electronic systems to conducted disturbances in the frequency range from 150 kHz to 230 MHz are...
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Assessment of crack resistance of S355J2+N steel according to SEP 1390 standard
PublicationThe aim of the study was to evaluate the weldability of S355J2+N steel by bending test according to SEP 1390. In the specimen from S355J2+N steel 3 external cracks were found, 1 of which were stopped in the fusion line and 2 in heat affected zone. Results of bending test for investigated grade of steel are positive.
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Przemoc w stosunkach ukraińsko-rosyjskich w opinii polskiej prasy codziennej
PublicationThe five most widely read Polish newspapers informing about the creation Maidan in Kiev and protests against decisions of the Ukrainian authorities revealed the existence of internal political violence. The external violence is associated with the inclusion of Russia into the conflict. Since the turn of 2013/2014 in Ukrainian-Russian relations were recorded examples of economic violence.
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Model dynamic electrochemical impedance spectroscopy (DEIS) results obtained with various DC polarization rates
Open Research DataThe dataset contains results of model dynamic electrochemical impedance spectroscopy studies carried out on a setup of 10 diodes in series, which were connected in parallel with a condenser. The impedance data were acquired every 1 s (the analytic window length for Fourier Transform was 1 s). The model system was polarized between 0 and +8 V with DEIS...
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Badania laboratoryjne wybranych sposobów koordynacji regulatora transformatora blokowego oraz regulatora generatora
PublicationWprowadzenie wymogu stosowania transformatorów blokowych z przekładnią regulowaną pod obciążeniem spowodowało konieczność określenia właściwego sposobu podziału kryteriów sterowania pomiędzy regulator generatora a regulator transformatora blokowego. W referacie zwrócono uwagę na aspekt miejsca pomiaru napięć. Ma to istotny wpływ zarówno na algorytm jak i jakość regulacji. Rozważania teoretyczne zilustrowane zostały wynikami prób...
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Selected problems of earth fault loop impedance testing in circuits fed from UPS
PublicationIn the paper a principle of earth fault loop impedance testing in low voltage systems has been presented. Selected factors, influencing accuracy of the testing, are indicated. A structure of UPS of VFI-type and the problem of impedance testing in circuits with such type of UPS are discussed.
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The radiated immunity test of an astable multivibrator for various supply voltages
Open Research DataThe dataset presents a result of measurements that are a part of electromagnetic field immunity tests. The radiated, radio frequency, immunity tests were carried out for a typical astable electronic multivibrator supplied from a power supply with an output voltage of 6V and 7.5 V. Tests of immunity of electronic systems to radiated radio frequency (RF)...
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Przekształtniki tranzystorowe działające w trybie prądu trójkątnego
PublicationPrzekształtniki oparte na węgliku krzemu mogą być analizowane jako źródła napięcia lub prądu niezależnie od topologii przy odpowiednich parametrach filtru wyjściowego. Szczególnie interesujące są falowniki napięcia działające w trybie prądu trójkątnego. W referacie przedstawiono sterowanie trójfazowym falownikiem napięcia posiadającym właściwości źródła prądu. Pokazano, jak dobrać parametry filtru wyjściowego falownika. Oceniono...
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Estimation of Selected Synchronous Generator Parameters Based on the Gradient Method
PublicationThe authors present a method for the estimation of synchronous generator model parameters using a gradient algorithm. The paper shows an example of model parameter estimation for a turbogenerator and hydrogenerator, based on the generator voltage time responses obtained during an active and reactive power rejection test.
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Influence of electrode geometric arrangement on the operation of narrow circular electrostatic precipitator
PublicationIn this work the influence of electrode geometric arrangement on the operation of a circular electrostatic precipitator (ESP) was investigated using Particle Image Velocimetry (PIV) method. The ESP was a glass circular cylinder (29 mm in diameter, 300 mm long) equipped with a wire discharge electrode and circular-cylinder collecting electrode. The stainless-steel discharge wire electrode (0.23 mm in diameter, 100 mm long) was mounted...
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Feedback Control of Doubly-Fed Generator Connected to Current Source Converter
PublicationDoubly-fed induction generator (DFIG) system supplied by current source converter (CSC) is considered in this article. The DFIG can work in two independent modes: AC grid connection and stand-alone mode. The DFIG is connected to the ac grid directly through its stator and the CSC links the rotor side. In this mode, the active and reactive powers of the DFIG must be controlled. This article proposes two control system structures...
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BET specific surface area measurements of silica-coated bismuth oxide(Bi2O3) and gadolinium oxide (Gd2O3) structures
Open Research DataThe BET specific surface area was measured using an N2 adsorption/desorption isotherm (Micromeritics ASAP 2460, Norcross, GA, USA).
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Steady-State Vibration Level Measurement of the Five-Phase Induction Machine during Third Harmonic Injection or Open-Phase Faults
PublicationMultiphase electric machines are increasingly used in various industries and for electromobility. Complex systems have been developed for the control and powering of multiphase machines, which require verification. The quality of control and the power supply of electric machines is usually evaluated by analyzing various electrical parameters. On the other hand, taking into account the fact that a motor is an electrical-mechanical...
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New generation of the satellite hydraulic pumps
PublicationHydraulic satellite machines are known and produced in many versions, recognizable by the number of humps on their inner rotor and external gear, and therefore by the number of cooperating gears (satellites). All known shapes were however designed on the base of preliminary assumption that rotor’s and external gear’s pitch lines are formed by merging arcs, tangent to each other in the. This assumption makes calculations easier,...
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Excitation of Waves in a Dispersive Medium. Example of Flow of a Bubbly Liquid
PublicationThe excitation of wave motion by an external source and the interaction of modes inherent to a ow in a dispersive medium are considered. Dispersion is caused by the presence of gaseous bubbles in a liquid. A large variety of steady excited waveforms is possible when the exciting wave is also steady and propagates at a constant velocity. The velocities of the exciter and forced waves may be dierent. This leads to a variety of non-stationary...
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Assessment of the activities of private universities in the context of quality management in 2010
Open Research DataIn all universities, the assessment of the quality is made by the supervisor, the opinion of students and the admission of classes have the greatest impact on the assessment of the quality of education. Subsequent tracking of the student's fate has a slightly smaller impact on the grade. Research also shows that only 4 out of 7 respondents monitor the...
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Data from pizoelectric pressure sensor placed inside PWK pump chamber
Open Research DataThe dataset contains raw data acquired from a piezoelectric pressure sensor placed inside PWK pump chamber. Pumping pressure was 10MPa, displacement was set to 100%, oil temperature was 33C. Columns "Czas" stand for a time in seconds and milliseconds, "Napięcie" stands for Voltage in Volts
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Estimation of Synchronous Generator and AVR Parameters Based on Gradient and Genetic Methods
PublicationThe author present a method for the estimation of selected synchronous generator model and AVR parameters using a gradient and a genetic algorithm. The paper shows an example of model parameter estimation for a turbogenerator, based on the generator voltage time responses obtained during an active and reactive power rejection test
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The Influence of a Photovoltaic Micro-Installation on the Low-Frequency Parameters of Electricity at PCC and Its Impact on the Thermal Characteristics of Selected Devices
PublicationThis manuscript illustrates the measurement results of parameters describing the quality of energy at the PCC (point of common coupling) of a photovoltaic micro-installation that can significantly affect devices in the same power grid. The analyses reflecting heating of selected devices used in domestic installations, which were performed in an isolated laboratory environment, are also indicated. The conducted study aimed at checking...
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Ceramic composites for single-layer fuel cells
PublicationComposite materials consisting of acceptor doped lanthanum orthoniobate electrolyte phase (La0.98Ca0.02NbO4) and Li2O:NiO:ZnO semiconducting phase were synthesized. The precursor powder of La0.98Ca0.02NbO4 was prepared in nanocrystalline (mechanosynthesis) and microcrystalline (solid-state synthesis) form. The composite can be applied in a single-layer fuel cell, because of the presence of two phases acting as an anode and a cathode...
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SiC-based T-type modules for multi-pulse inverter with coupled inductors
PublicationThe paper presents SiC-based three-level T-type modules designed for a high-performance 30kVA DC/AC inverter operating at high frequency 85 kHz with low THD of the output voltage. This inverter system consists of two integrated parts. The first part is active and contains three parallelconnected three-phase T-type modules built with fast-switching SiC power transistors. The second, passive part of the system is a set of inductors...
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PUBLICZNE ŚRODKI TRANSPORTOWE A SAMOCHÓD ELEKTRYCZNY W OBSŁUDZE PODRÓŻY MIEJSKICH W METROPOLII TRÓJMIEJSKIEJ
PublicationMetropolia trójmiejska ma wyjątkowo negatywne uwarunkowania terenowe dla funkcjonowania i rozwoju sieci komunikacji publicWyznej. Dzielnice położone w tzw. dolnym tarasie są dobrze skomunikowane za pomocą linii SKM i tramwajowych. Jedynie te środki komunikacji szynowej, przy częstotliwości połączeń nie większej niż co 10 minut, są konkurencyjne dla indywidualnych dojazdów samochodami osobowymi. Natomiast autobusy i trolejbusy utykające...
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Experimental ORC micro-power plant for CHP application Part A: power plant arrangement
PublicationThe co-generative micro-power plant with the HFE7100 applied as a working medium was designed and built for experimental investigations. The heat output of the plant was assumed equal to 20 kW, while the electric output amounted to about 3kW. Examples of the results of the preliminary experimental research on a boiler, heat exchangers, a pump and a turbine-generator set are presented and analysed.
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Five-phase Induction Motor Drive Operation During Stator Phase Fault
PublicationThe article presents the most important advantages of multi-phase electric drives. The construction of a five-phase squirrel cage induction motor together with possible stator winding distribution cases is presented, which affect the properties of such motor. Increased reliability of five-phase drives was indicated. The drive operation properties were confirmed by experimental results.
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BET specific surface area measurements of silica-coated bismuth oxide (Bi2O3)/gadolinium oxide (Gd2O3) core-shell structures
Open Research DataThe BET specific surface area was measured using an N2 adsorption/desorption isotherm (Micromeritics ASAP 2460, Norcross, GA, USA).
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SELECTED PROBLEMS OF MACHINE DYNAMICS (2024)
e-Learning CoursesThe course is devoted towards lectures assocuated with the novel issues of machine and structures dynamics. The following lectures will be given during the SPMD course: - introduction to selected problems of machine dynamics, - definition of the machine and structure working environment, - internal and external loads on machines and structures, - dynamics of machines and structures, - strength of machines and structures, - special...
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WYMAGANIA STAWIANE LEKKIEJ OBUDOWIE
PublicationW artykule omówiono wymagania stawiane lekkim obudowom. Przywołano odpowiednie normy i rozporządzenia dotyczące zagadnień ogólnobudowlanych i techniczno-użytkowych.
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Ampacity of power cables exposed to solar radiation – recommendations of standards vs. CFD simulations
PublicationThe aim of the paper is to evaluate the ampacity of a low-voltage single power cable according to: 1) recommendations of the standard IEC 60287, 2) a Computational Fluid Dynamics method, implemented in Ansys software; and comparison of the results obtained for these two cases. Moreover, limitations of recommendations of the above mentioned standard are indicated.
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Control strategy for the multilevel cascaded H-bridge converter
PublicationThe paper presents the control strategy for Cascaded H-bridge (CHB) converter . The converter output voltage using Space-Vector Pulse Width Modulation (SV-PWM) strategy is controlled. The DC-link voltages are controlled by appropriate choice of H-Bridges and appropriate choice of active and passive vectors.
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Nanotubular oxide layer formed on helix surfaces of dental screw implants - SEM examination
Open Research DataThe samples used for the research had the shape of a helix with a metric thread, with their geometry imitating a dental implant. The oxide layer was produced by a standard electrochemical method in an environment of 1M H3PO4 + 0.3 % HF for 20 min, at a constant voltage of 30 V. The oxidized samples were analyzed with a scanning electron microscope.
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Reduction of road traffic noise by source measures — present and future strategies
PublicationThe current trend worldwide is less focused on reducing road traffic noise. This is in strong contrast to the severe impact of traffic noise to the general health and quality of life. A more holistic and combined strategy is needed. Current international rules and regulations regarding vehicles and tyres are not sufficient to reduce traffic noise levels in an effective way. Calculations show that these regulations will only yield...
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Oriented Gaussian beams for high-accuracy computation with accuracy control of X-ray propagation through a multi-lens system
PublicationA highly accurate method for calculating X-ray propagation is developed. Within this approach, the propagating wave is represented as a superposition of oriented Gaussian beams. The direction of wave propagation in each Gaussian beam agrees with the local direction of propagation of the X-ray wavefront. When calculating the propagation of X-ray waves through lenses, the thin lens approximation is applied. In this approximation,...
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Surface Dielectric Barrier Discharge Plasma Actuators
PublicationThis paper presents a part of the works conducted in the Plasmaero European project (task 1.1) on surface dielectric barrier discharge actuators applied to airflow control. The study is divided into several parts. In the first part, the goal is to enhance the electric wind produced by a typical single DBD actuator by optimization of the active electrode shape. For instance, the use of a thin wire instead of a plate air-exposed...
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Speed sensorless induction motor drive with predictive current controller
PublicationToday, speed sensorless modes of operation are becoming standard solutions in the area of electric drives. This paper presents a speed sensorless control system of an induction motor with a predictive current controller. A closed-loop estimation system with robustness against motor parameter variation is used for the control approach. The proposed algorithm has been implemented using field-programmable gate arrays (FPGAs) and a...