Filters
total: 3822
filtered: 3139
-
Catalog
Chosen catalog filters
displaying 1000 best results Help
Search results for: power spectral density
-
The Effect of Surface Topography Feature Size Density and Distribution on the Results of a Data Processing and Parameters Calculation with a Comparison of Regular Methods
Publication -
IR–Raman, NMR and density functional methods in the examination of tautomerism and features of N-methyl substituted 9-acridinamine derivatives
Publication -
Maximum Power Point Technique (MPPT) for PV System Based on Improved Pert and Observe (P&O) Method with PI Controller
PublicationPhotovoltaic power generation system has key rule in electricity production. Although, it is clean renewable energy with unlimited resources but it has some drawbacks in efficiency. In order to maximize the efficiency, PV array must drive at maximum power point. For the reason so, several algorithms are used in PV system to track MPP and reduce the...
-
Transient States during Short-circuit in a Line Powered by UPS and its Impact on Earth Fault Loop Impedance Measurement and Power Quality
PublicationThe short-circuit in a line powered by Uninterruptible Power Supply (UPS) during different UPS operation modes is presented in the article. The transient state condition related to the short-circuit in a line fed from double conversion On-line UPS is discussed in detail. The results of the measurements of earth fault loop impedance (FLI) in circuits powered by UPS with the instruments of various manufacturers are presented. The...
-
Design of a simple modular active power electronic transformer
Publication -
Predictive control system of the shunt active power filter
Publication -
The Influence of LED Lighting Sources on the Nature of Power Factor
Publication -
New control system of the shunt active power filter
Publication -
Analog multiplier for a low-power integrated image sensor
PublicationArtykuł przedstawia nowe podejście do projektowania tanich niskomocowych zintegrowanych sensorów optycznych. W odróżnieniu od wcześniej stosowanych rozwiązań opartych na masowym przetwarzaniu równoległym, zaproponowany mnożnik macierzowy charakteryzuje się korzystniejszymi cechami. Proponowane rozwiązanie, chociaż mniej elastyczne w sensie liczby możliwych do zaimplementowania algorytmów wstępnej obróbki obrazu, cechuje się znaczącą...
-
Analog multiplier for a low-power integrated image sensor
PublicationArtykuł przedstawia nowe podejście do projektowania tanich niskomocowych zintegrowanych sensorów optycznych. W odróżnieniu od wcześniej stosowanych rozwiązań opartych na masowym przetwarzaniu równoległym, zaproponowany mnożnik macierzowy charakteryzuje się korzystniejszymi cechami. Proponowane rozwiązanie, chociaż mniej elastyczne w sensie liczby możliwych do zaimplementowania algorytmów wstępnej obróbki obrazu, cechuje się znaczącą...
-
Power devices in Polish National Silicon Carbide Program
PublicationArtykuł zawiera informacje o polskim rządowym programie ''Nowe technologie na bazie węglika krzemu i ich zastosowania w elektronice wielkich częstotliwości, dużych mocy i wysokich temperatur''. Program zawiera trzy główne zadania zawierające następujące cele: wytworzenie podłoży z SiC, wytworzenie przyrządów z SiC oraz ocenę działania wybranych przyrządów w układach aplikacyjnych. Omówiono zastosowane metody wytwarzania podłoży,...
-
<title>High power optical fiber capillaries</title>
Publication -
Power Converter Solutions for Industrial PV Applications—A Review
Publication -
Dynamic model of nuclear power plant steam turbine
Publication -
The assessment of exploitation process of power for access control system
Publication -
Power Converter Solutions for Industrial PV Applications—A Review
Publication -
A conceptual framework for assessing power and governance in contemporary democracy
Publication -
Prospects of Decreasing Power Losses in a Hydrostatic Thrust Bearing
PublicationIn numerous machines, axial load is carried by tilting pad thrust bearings known since the beginning of 20th century. These bearings are commonly bath lubricated, which is simple, does not require any additional pumps, and, due to this, such systems are highly reliable. In a contemporary technology, however, minimization of friction losses became an important goal of machinery improvement. Calculations based on elementary rules...
-
Effect of power frequency on the stress state of disc actuator
PublicationThis paper presents the concept of determining the optimum frequency of coil supply in inductive-dynamic drive. As a criterion to obtain the sought frequency, the smallest value of reduced stress in the disc was assumed while maintaining the desired dynamics. The disc stress is determined on the basis of solution of vibrating thin plate equation. Magnetic pressure acting on the disc is obtained from a hybrid circumferentially-field...
-
Effect of power frequency on the stress state of disc actuator
PublicationThe paper presents the concept of determinig the optimum frequency of coil supply in inductive-dynamic drive. As a criterion to obtain the sought frequency, the smallest value of reduced stress in the disc was assumed while maintaining the desired dynamics.
-
Wind Turbine Operation in Electric Power System.Advanced Modelling
PublicationW monografii przedstawiono zagadnienia związane z pracą elektrowni wiatrowych w systemie elektroenergetycznym, a w tym przedstawiono wpływ elektrowni wiatrowych na system elektroenergetyczny (jakość energii elektrycznej). Omówiono zasady modelowania elektrowni wiatrowych różnych typów, tj. z generatorami asynchronicznymi i synchronicznymi, pracujących w systemie elektroenergetycznym. Przestawiono wybrane modele elektrowni wiatrowych...
-
Computer simulator of the synchronization proces of power generating units
PublicationPrzedstawiono istotę procesu synchronizacji w systemie elektroenergetycznym oraz podano metodykę badania synchronizatorów automatycznych. Wskazano na użyteczność komputerowego symulatora procesu synchronizacji prądnic. Opisano architekturę symulatora, jego system komputerowy oraz podsystem wizualizacji. Wyciągnięto wnioski.
-
Hardware-in-the-loop simulation of the synchronization process of power generators
PublicationPrzedstawiono nowoczesne urządzenia do badań synchronizatorów automatycznych w warunkach laboratoryjnych. Szczególną uwagę poświęcono systemowi wizualizacji tych urządzeń )przy ich pomocymożliwa jest ciągła kontrola, sterowanie i wizualizacja procesem synchronizacji w systemie elektroenergetycznym.
-
A probabilistic model of envirinmental safety of ship power plant.
PublicationPrzedstawiono probabilistyczne podejście do oceny bezpieczeństwa środowiskowego siłowni statku. Wyznaczono miarę ryzyka oraz kryterium ryzyka środowiskowego siłowni statku.
-
Demagnetization of the core and reduction of power transformer inrush current
PublicationW artykule przedstawiono metodę ograniczenia prądów włączania transformatora energetycznego za pomocą demagnetyzacji rdzenia magnetycznego. Jako źródło energii do demagnetyzacji w proponowanej metodzie zastosowano kondensator. Do wytworzenia pola rozmagnesowującego wykorzystano uzwojenia robocze transformatora. Przeprowadzono obliczenia magnetyzmu szczątkowego rdzenia po demagnetyzacji dla różnych wartości pojemności, napięcia...
-
Photovoltaic maximum power point varying with illumination and temperature
PublicationW pracy przedstawiono wyniki badań eksperymentalnych zmian położenia punktu maksymalnej mocy na charakterystyce prądowo-napięciowej modułu ogniw fotowoltaicznych, związanych ze zmieniającą się temperaturą i natężeniem padającego promieniowania. Badano czas narastania napięcia pracy i temperatury ogniw w początkowej fazie ekspozycji na promieniowanie słoneczne. Przedstawiono niektóre praktyczne aspekty zastosowania układu automatycznego...
-
Selection of C-Type Filters for Reactive Power Compensation and Filtration of Higher Harmonics Injected into the Transmission System by Arc Furnaces
PublicationThis article presents a method for selecting the elements of a C-type filter working with a conventional LC-type filter for compensating reactive power and filtering out higher harmonics generated by arc furnaces and ladle furnaces. The study was conducted in a steel mill supplied by a 110 kV transmission system, where higher harmonic currents and nonlinear loads were measured. A series of computer simulations were performed under...
-
Performance of a single layer fuel cell based on a mixed proton-electron conducting composite
PublicationMany of the challenges in solid oxide fuel cell technology stem from chemical and mechanical incompatibilities between the anode, cathode and electrolyte materials. Numerous attempts have been made to identify compatible materials. Here, these challenges are circumvented by the introduction of a working single layer fuel cell, fabricated from a composite of proton conducting BaCe0.6Zr0.2Y0.2O3-δ and a mixture of semiconducting...
-
Operational problems of large power diesel engines combusting biofuels, considered togetherwith assessment of their operation
PublicationWithin this article the issue of large power self ignition engines fed with biofuels has been undertaken. The analysis focused mainly on operation problems. There has been noticed some advantages and difficulties associated with the biofuel application to self ignition engines. The research problem has been characterised and the research purposes have been proposed enabling the most profitable formation of energetic features of...
-
Stability Analysis of Shunt Active Power Filter with Predictive Closed-Loop Control of Supply Current
PublicationThis paper presents a shunt active power filter connected to the grid via an LCL coupling circuit with implemented closed‐loop control. The proposed control system allows selective harmonic currents compensation up to the 50th harmonic with the utilization of a model‐based predictive current controller. As the system is fully predictive, it provides high effectiveness of the harmonic reduction, which is proved by waveforms achieved...
-
Low-Voltage Low-Power Filters with Independent ω0 and Q Tuning for Electronic Cochlea Applications
PublicationAn acoustic second-order low-pass filter is proposed for filter banks emulating the operation of a human cochlea. By using a special filter structure and an innovative quality (Q)-factor tuning technique, an independent change of the cutoff frequency (ω0) and the Q-factor with unchanged gain at low frequencies is achieved in this filter. The techniques applied result in a simple filter design with low Q-factor sensitivity to component...
-
DEPO: A dynamic energy‐performance optimizer tool for automatic power capping for energy efficient high‐performance computing
PublicationIn the article we propose an automatic power capping software tool DEPO that allows one to perform runtime optimization of performance and energy related metrics. For an assumed application model with an initialization phase followed by a running phase with uniform compute and memory intensity, the tool performs automatic tuning engaging one of the two exploration algorithms—linear search (LS) and golden section search (GSS), finds...
-
ANALYSIS OF THE IMPACT OF THE PLANNED SEWAGE DISCHARGE FROM THE ‘NORTH’ POWER PLANT ON THE VISTULA WATER QUALITY
PublicationThe paper presents results of analysis of the industrial sewage discharge impact from the ‘North’ Power Plant on the Vistula water quality around 45+330 of the river kilometer. For the analysis, the two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined....
-
Modelling of in-plane wave propagation in a plate using spectral element method and Kane–Mindlin theory with application to damage detection
Publication -
Porphyrazine with bulky 2-(1-adamantyl)-5-phenylpyrrol-1-yl periphery tuning its spectral and electrochemical properties
Publication -
First detection of spectral resonance structures of the ionospheric Alfvén resonance in ULF/ELF magnetic field recorded at Suwałki, Poland
Publication -
Spectral characteristic of high-dose high-temperature emission from LiF:Mg,Cu,P (MCP-N) TL detectors
Publication -
Nickel(II) tri-tert-butoxysilanethiolates with N-heterocyclic bases as additional ligands: Synthesis, molecular structure and spectral studies
PublicationW publikacji przedstawiono metodę syntezy trzech kompleksów silanotiolanowych z takimi N-heterocyklicznymi zasadami jak: pirydyna, 2-metylopirydyna i 3,5-dimetylopirydyna. Dla tych kompleksów przeprowadzono badania X-Ray, analizy elementarnej. Przy pomocy rentgenowskiej analizy strukturalnej wykazano różną koordynację atomu centralnego - niklu.
-
Structural, spectral and magnetic properties of Ni(II), Co(II) and Cd(II) compounds with imidazole derivatives and silanethiolate ligands
PublicationA series of new metal heteroleptic complexes have been obtained in simple reactions of 1-(3-aminopropyl)-imidazole (api) and 1,4-bis(imidazol-1-yl)-butane (bbi) ligands with metal silanethiolates or acetylacetonates. The obtained complexes are the coordination polymers [Ni{SSi(tBuO)3}2(μ-api)]n1, [Co{SSi(tBuO)3}2(μ-api)]n2, [Cd{SSi(tBuO)3}2(μ-api)·2CH3OH]n3, [Cd{SSi(tBuO)3}2(μ-bbi)·CHCl3]n4 and the dimer [Co{SSi(tBuO)3}2(μ-bbi)·3CH3OH]25....
-
Event-Triggered Communication in Cooperative, Adaptive Model Predictive Control of a Nuclear Power Plant’s Turbo–Generator Set
PublicationThis paper discusses the issue of optimizing the communication between the components of a cooperating control system formed by a pair of MPC controllers of a nuclear power plant turbine set using online recursive least squares identification. It is proposed to use event-triggered communication, i.e., sending information only at selected time instants, as opposed to the standard approach where communication is triggered by time...
-
Density functional theory-based simulations of sum frequency generation spectra involving methyl stretching vibrations: effect of the molecular model on the deduced molecular orientation and comparison with an analytical approach
PublicationThe knowledge of the first hyperpolarizability tensor elements of molecular groups is crucial for a quantitative interpretation of the sum frequency generation (SFG) activity of thin organic films at interfaces. Here, the SFG response of the terminal methyl group of a dodecanethiol (DDT) monolayer has been interpreted on the basis of calculations performed at the density functional theory (DFT) level of approximation. In particular,...
-
European Multicenter Evaluation of High-Density DNA Probe Arrays for Detection of Hepatitis B Virus Resistance Mutations and Identification of Genotypes
Publication -
The associations between serum VEGF, bFGF and endoglin levels with microvessel density and expression of proangiogenic factors in malignant and benign ovarian tumors
Publication -
Radiation dose distributions in three dimensions from tomographic optical density scanning of polymer gels: I. Development of an optical scanner
Publication -
Scrutiny of power grids by penetrating PV energy in wind farms: a case study of the wind corridor of Jhampir, Pakistan
PublicationThis study examines the problems caused by intermittent renewable energy sources, especially wind farms, and suggests a different solar energy penetration strategy to improve their loading capacity. The study uses real-time data from a wind farm in Jhampir, Pakistan, to analyse and assess various aspects of grid stations connected to wind farms. Electrical Transient Analyzer Program is used to validate the results by linking...
-
Scrutiny of power grids by penetrating PV energy in wind farms: a case study of the wind corridor of Jhampir, Pakistan
PublicationThis study examines the problems caused by intermittent renewable energy sources, especially wind farms, and suggests a different solar energy penetration strategy to improve their loading capacity. The study uses real-time data from a wind farm in Jhampir, Pakistan, to analyse and assess various aspects of grid stations connected to wind farms. Electrical Transient Analyzer Program is used to validate the results by linking these...
-
Influence of reactive oxygen species during deposition of iron oxide films by high power impulse magnetron sputtering.
PublicationIron oxide films were deposited using high power impulse magnetron sputtering (HiPIMS) of an iron cathode in an argon/oxygen gas mixture at different gas pressures (0.5~Pa, 1.5~Pa, and 5.0~Pa). The HiPIMS system was operated at a repetition frequency $f = 100$~Hz with a duty cycle of 1~\%. A main goal is a comparison of film growth during conventional and electron cyclotron wave resonance-assisted HiPIMS. The deposition plasma...
-
Spectroscopic studies on physicochemical properties of selected unsymmetrical bisacridine derivatives and NMR analysis of their interactions with the model sequence Pu22 aided by molecular dynamics
PublicationIn recent years, new promising acridine derivatives have appeared, belonging to the unsymmetrical bisacridines (UAs) family with high anticancer activity. Both their physicochemical properties and their mechanism of action at the molecular level have not been thoroughly analyzed so far. Four derivatives were selected for the study, termed as: C-2028, C-2041, C-2045 and C-2053. The first aim of this work was to determine the protonation...
-
Design and evaluation of a base module of active power electronic transformer
Publication -
A Special Multi-Pulse Converter with Small Active Power Filter
Publication