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Search results for: impedancja uziemienia
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Fabrication and Study of BiNbO4 Ceramics
PublicationAim of the present research was to fabricate and study crystalline structure as well as dielectric properties of BiNbO4 ceramics. In the present study BiNbO4 ceramics was fabricated by solid state reaction from the mixture of simple oxides viz. Bi2O3, and Nb2O5. Stoichiometric mixture of the powders was thermally analyzed so parameters of the thermal treatment were determined. The EDS measurements proved conservation of the chemical...
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Experimental and Quantum Chemical Evaluation of 8-Hydroxyquinoline as a Corrosion Inhibitor for Copper in 0.1 M HCl
PublicationThe corrosion inhibition properties of 8-hydroxyquinoline (8-HQ) in 0.1 M HCl for copper have been investigated by using experimental (electrochemical impedance spectroscopy (EIS), dynamic electrochemical impedance spectroscopy (DEIS), and potentiodynamic polarization) and theoretical methods complemented by surface morphological examination with the aid of scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy...
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A Broadband Circularly Polarized Wide-Slot Antenna with a Miniaturized Footprint
PublicationThis letter presents a novel and simple feeding technique for exciting orthogonal components in a wide-slot antenna. In this technique, a rectangular bracket-shape parasitic strip is placed at the open end of the straight microstrip line to excite the fundamental horizontal and vertical components of the circular polarization (CP). The proposed technique—when employed in conjunction with the asymmetrical geometry of coplanar waveguide...
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Low-Profile Interdigitated UHF RFID Tag Antenna for Metallic Objects
PublicationThis article presents a novel miniature interdigitated ultra-high frequency (UHF) radio frequency identification (RFID) tag antenna that can be placed on metallic objects. The tag structure comprises two horizontal strip lines, each loaded with seven identical open stubs, and an integrated circuit (IC) chip connected directly to the feed lines in the middle of the structure. The perfect match to the IC chip’s impedance is realized...
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New ceramic materials derived from pyrolyzed poly(1,2-dimethylsilazane) and starch as a potential anode for Li-ion batteries
PublicationNewmaterialswere obtained by pyrolysis of starch (S) and poly(1,2-dimethylsilazane) (PSN) (weight ratio: PSN/S 30/70) at temperature a) 500 °C, b) 700 °C and c) 900 °C. Ceramic materials were characterized by infrared spectroscopy, TGA, Raman spectroscopy and SEM. New Si\O and shifted Si\C stretching vibration modes emerged confirming direct interaction between silicon originating fromsilazane and oxygen coming fromstarch. The...
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Constrained optimization for generating gain-bandwidth design trade-offs of wideband unidirectional antennas
PublicationBroadband unidirectional antennas realised in microstrip technology find applications in many wireless communication systems. One of their design challenges is the necessity of handling multiple performance figures which is difficult when using traditional design methods, largely based on parameter sweeping. This work presents a simple optimisation-based framework that permits generation of gain-bandwidth trade-off designs for...
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Feedline Alterations for Optimization-Based Design of Compact Super-Wideband MIMO Antennas in Parallel Configuration
PublicationThis letter presents a technique for size reduction of wideband multiple-input-multiple-output (MIMO) antennas. Our approach is a two-stage procedure. At the first stage, the antenna structure is modified to improve its impedance matching. This is achieved through incorporation of an n-section tapered feedline, followed by reoptimization of geometry parameters. Reducing the maximum in-band reflection well beyond the acceptance...
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Non-destructive adhesion control.
PublicationW przeciwieństwie do innych metod, spektroskopia impedancyjna jest zdolna do wyznaczania adhezji międzywarstwowej np. systemu powłokowego stosowanego do ochrony samochodów basecoat/clercoat ''in situ'' i niedestrukcyjnie. Obniżenie adhezji międzywarstwowej przebiega analogicznie jak zmiany energi aktywacji przewodnictwa jonowego w obszarze międzywarstwowym, co jest mierzone przy pomocy spektroskopii impedancyjnej. Stosując przewodzące...
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An Analysis of Probe-Fed Rectangular Patch Antennas With Multilayer and Multipatch Configurations on Cylindrical Surfaces
PublicationA multi-patch configuration of probe-fed rectangular microstrip antennas mounted on a cylindrical body, with electrically small radius, with an arbitrary number of substrate and superstrate layers is investigated in this paper. A full-wave analysis and a moment-method calculation are employed. A unified procedure for creating proper matrices for the investigated geometry of the structure is outlined here. Numerical results for...
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Current commutation process in a ultra-fast fuse-IGBT hybrid circuit breaker.
PublicationUkład hybrydowy bezpiecznika topikowego i tranzystora IGBT umożliwia bardzo szybkie włączenie do obwodu zwarciowego impedancji ograniczającej wartość prądu. Po eksplozji krótkiego topika bezpiecznika wywołanej narastającym prądem zwarciowym wywołuje w czasie poniżej 2 ms wzrost napięcia na topiku do wartości ok.20 - 25V, po czym prąd jest komutowany do gałęzi z przyrządem półprzewodnikowym typu GTO lub IGBT. Ostateczne wyłączenie...
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analizator do spektroskopii wysokoimpedancyjnej z wykorzystaniem cps
PublicationW artykule przedstawiono opracowany i wdrożony do produkcji seryjnej analizator do spektroskopii wysokoimpedancyjnej. Dzięki zastosowaniu obwodu wejściowego w postaci sondy pomiarowej (2 i 3 zaciskowej) analizator umożliwia pomiary w zakresie 100 ohm < |Zx| < 100 Gohm. Do wyznaczania składowych ortogonalnych sygnałów pomiarowych wykorzystano technikę cyfrowego przetwarzania sygnałów. Pozwoliła ona na pomiary w szerokim zakresie...
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Ocena systemów uziemień z wykorzystaniem pomiarów metodą udarową
PublicationW artykule zostały omówione procedury i wymagania stawiane systemom uziemień przez przepisy normalizacyjne z punktu widzenia ich skuteczności w systemie ochrony odgromowej. Podstawą tak sformułowanej oceny są pomiary z zastosowaniem metody udarowej. Metoda taka okazuje się bardzo przydatna zwłaszcza w przypadku uziemień rozległych, jakie pojawiają się we współczesnych obiektach wskutek połączenia różnych elementów uziemiających...
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Rozległe systemy uziemień w ochronie odgromowej
PublicationW artykule zostały omówione procedury i wymagania stawiane systemom uziemień przez przepisy normalizacyjne z punktu widzenia ich skuteczności w systemie ochrony odgromowej. Podstawą tak sformułowanej oceny są pomiary z zastosowaniem metody udarowej. Metoda taka okazuje się bardzo przydatna zwłaszcza w przypadku uziemień rozległych, jakie pojawiają się we współczesnych obiektach wskutek połączenia różnych elementów uziemiających...
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A novel concept for tissue-metal detection and differentiation using an inductive proximity sensor
PublicationIn this paper a novel application of inductive proximity sensors for detection of living tissue by means of measurements of the coil impedance changes at different frequencies is described. The mathematical analyses utilizing Bessel function estimation include detected object size and its distance from a sensor. The main aim of this study is to prove the possibility of distinguishing between metal objects and living tissues. The...
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Hybrid Analysis of Structures Composed of Axially Symmetric Objects
Publication— A hybrid method for the scattering problems in shielded and open structures is presented. The procedure is based on the combination of body-of-revolution involving finite-element methods with impedance matrix formulation and the mode-matching technique, which can be utilized for the analysis of structures with axially symmetrical scatterers. In order to confirm the validity and efficiency of the proposed approach, a few examples...
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Domain Reduction in Hybrid Technique for Electromagnetic Wave Scattering Problems
PublicationThis paper proposes a combination of the field matching technique, finite element method and generalized impedance matrix, the main idea of which is to reduce the computational domain by surrounding a scatterer with the smallest convex shape and applying the field matching technique. This approach can be applied for arbitrary shaped scatterers and types of materials and allows for the reduction of the computational domain. In order...
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Oxygen partial pressure and temperature dependence of series resistance of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element series resistance at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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New insights into structural, optical, electrical and thermoelectric behavior of Na0.5Bi0.5TiO3 single crystals
PublicationThe single crystals of lead-free Na0.5Bi0.5TiO3 were grown using the Czochralski method. The energy gaps determined from X-ray photoelectron spectroscopy (XPS) and optical measurements were approximately 2.92 eV. The current-voltage characteristics, depolarization current, dc (σdc) and ac (σac) electrical conductivity, and Seebeck coefficient of the crystals were investigated. The frequency/temperature-dependent electrical properties...
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Improved Performance of 1-Ethyl-3-Methylimidazolium Tetrafluoroborate at Steel/HCl Interface by Iodide Ions
PublicationThe corrosion and corrosion inhibition of St37 steel in 0.1 M HCl solution by 1-ethyl-3-methylimidazolium tetrafluoroborate (EMITFB) and the effect of addition of KI on the inhibitive performance of EMITFB have been examined by electrochemical [electrochemical impedance spectroscopy, potentiodynamic polarization, and dynamic electrochemical impedance spectroscopy (DEIS)] and surface examination [scanning electron microscope (SEM)...
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Understanding the origin of high corrosion inhibition efficiency of bee products towards aluminium alloys in alkaline environments
PublicationVarious bee products were found to be efficient corrosion inhibitors of aluminium in different environments. In particular, bee pollen was found to be highly effective in alkaline electrolytes, yet its highly complex composition and possible synergistic interactions hinder determination of the compounds acting as active corrosion inhibitors. The main purpose of the following work is to investigate the effect of solvents used for...
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A Series-Inclined-Slot-Fed Circularly Polarized Antenna for 5G 28-GHz Applications
PublicationThis letter presents the design of a single-point-fed, geometrically simple circularly polarized (CP) antenna for 28 GHz Ka-band applications. The proposed antenna is based on a straight microstrip line printed on one side and coupled with the nearly square patches through a 45-degree inclined V-shape slot aperture on the other side. In order to generate circular polarization, the fundamental radiating mode is degenerated at a...
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A body position influence on ECG derived respiration
PublicationAn influence of a human body position on ECG derived respiration (EDR) signal is presented in the paper. Examinations were performed during deep, suspended and normal breathing for eight people in four different body positions. EDR and thoracic impedance signals were compared using correlation and standard deviation coefficients. Obtained results have shown that it is possible to monitor breath activity of people being in different...
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Novel microstrip low-pass filters with fractal defected ground structures
PublicationIn this study, three microstrip low-pass filters (LPFs) containing fractal-shaped defected ground structures have been designed and manufactured. To improve the performance of microstrip LPF, cascades of inductively coupled fractal resonators have been applied. Simultaneously, to achieve relatively constant microstrip impedance resulting in essentially low reflection losses, a modification of the strip geometry has been introduced....
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Differential analysis of dynamic immittance spectra
PublicationThis work presents a new approach to the analysis of immittance spectrograms of systems characterised by non-stationarity. The possibility of linking the evolution of the immittance response with changes in the parameters describing the system is achieved by introducing a spectrum in differential form. By using the above procedure, it becomes possible to separate elements with a dependence (or lack thereof) from an independent...
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Low-Cost Surrogate Modeling of Miniaturized Microwave Components Using Nested Kriging
PublicationIn the paper, a recently reported nested kriging methodology is employed for modeling of miniaturized microwave components. The approach is based on identifying the parameter space region that contains high-quality designs, and, subsequently, rendering the surrogate in this subset. The results obtained for a miniaturized unequal-power-split rat-race coupler and a compact three-section impedance transformer demonstrate reliability...
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Investigation of pitting corrosion of aluminum by using deis methodbadanie korozji wżerowej aluminium przy użyciu metody deis
PublicationBadano odporność korozyjną stopu aluminium 1100. Zastosowano dynamiczną spektroskopię impedancyjną w połączeniu. Na podstawie uzyskanych wyników impedancyjnych i polaryzacyjnych zaproponowano elektryczny schemat zastępczy dla aluminium korodującego w warunkach dużej zawartoći jonów chlorkowych. Stwierdzono, że dynamiczna elektrochemiczna spektroskopia impedancyjna jest bardzo dobrym narzędziem do badania procesów korozyjnych oraz...
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Lithium ion insertion into poly(3,4-ethylenedioxythiophene) films from propylene carbonate electrolytes.
PublicationPolimerowa matryca złożona z poli(3,4-etylenodioksytiofenu z poli(styrenosulfonianem) otrzymana została na drodze syntezy elektrochemicznej. Transport jonowy w matrycy polimerowej w kontakcie z węglanem propylenu zawierającym LiClO4 został scharakteryzowany za pomocą metody impedancji ac oraz chronowoltoamperometrii. Wyznaczono przewodność jonową matrycy oraz efektywne współczynniki dyfuzji dla kationu Li+. Wielkości te...
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Assessment of protective properties of rubber lining in absorbers of flue gas desulphurization systems.
PublicationResults of research on degradation of rubber lining which is the main protection of absorbers in flue gas desulphurization (FGD) systems were presented. The power plant where the system operated is lignite-fired. Owing to measurements using electrochemical impedance spectroscopy and gravimetric determination of water content in the lining, the areas of the system which are most exposed to degradation were shown. The results obtained...
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The electrochemical response to BDD electrode functionalization with CD147 receptor
Open Research DataThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with CD147 receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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Gold nanocubic structures agglomeration when put on conductive surfaces
Open Research DataThis dataset contains Dynamic EIS results obtained for the gold electrodes with non-functionalized gold nanocubes (AuNC) deposited at its surface. The deposition was the following: 2 uL of the solvent containing CTAB as the surfactant was put on the electrode and dried, the same procedure was applied 5 times. Afterward, the electrode was immersed in...
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The electrochemical response to BDD electrode functionalization with ACE2 receptor
Open Research DataThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with ACE2 receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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The electrochemical response to BDD electrode functionalization with IgG2B receptor
Open Research DataThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with IgG2B receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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Gold nanocubic structures agglomeration when put on conductive surfaces
Open Research DataThis dataset contains Dynamic EIS results obtained for the gold electrodes with non-functionalized gold nanocubes (AuNC) deposited at its surface. The deposition was the following: 2 uL of the solvent containing CTAB as the surfactant was put on the electrode and dried, the same procedure was applied 5 times. Afterward, the electrode was immersed in...
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Electrochemical studies for screen-printed carbon electrodes (SPCE) with boron-doped diamond foils
Open Research DataThis dataset contains electrochemical examination of SPCE paste and SPCE containing boron-doped diamond BDD foils. The studies include kinetics analyses with cyclic voltammetry and electrochemical impedance spectroscopy with different redox probes: hexacyanoferrate(III) and Hexaammineruthenium(III) and potentiostatic open circuit potential at different...
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Oxygen partial pressure and temperature dependence of R-CPE2 frequency of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE2 frequency at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE1 capacity of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE1 capacity at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE1 frequency of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE1 frequency at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE2 capacity of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE2 capacity at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE1 resistance of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE1 resistance at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE2 resistance of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE2 resistance at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Dynamiczna aplikacja Internetowa ASP.NET silnika indukcyjnego jako elementu wirtualnego laboratorium maszyn elektrycznych
PublicationTematem referatu jest dynamiczna aplikacja internetowa, która umożliwia symulację obwodową silnika indukcyjnego trójfazowego Sg 100 L2 z wykorzystaniem interfejsu przeglądarki WWW. Model matematyczny silnika jest zdefiniowany w tzw. osiach naturalnych i sformułowany na podstawie metody energetycznej Lagrange’a. Do implementacji modelu maszyny w aplikacji internetowej wybrano projekt typu Web Forms, który jest składnikiem środowiska...
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Broadband Modeling of Motor Cable Impact on Common Mode Currents in VFD
PublicationExamination of conducted EMI generation and propagation in AC motor drives fed by frequency converter requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. AC motor winding voltage transients and related common mode currents are significantly correlated with resonance effects occurring in converter's load circuits. Intensity levels of these phenomena depend...
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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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System monitoringu odbieraków prądu pojazdów kolejowych w aspekcie bezpieczeństwa i ciągłości ruchu.
PublicationOmówiono metodę monitorowania stanu technicznego odbieraków prądu w oparciu o pomiar uniesienia przewodów jezdnych sieci trakcyjnej w czasie przejazdu pociągu. Opisano konstrukcję i zasadę działania wdrożonego na linii kolejowej pilotażowego stanowiska monitoringu. Przedstawiono metodę analizy i sposób wizualizacji wyników pomiarów. Zastosowany algorytm szacowania siły statycznej odbieraka uwzględnia prędkości pociągu i działanie...
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Zespół Metrologii i Optoelektroniki
Research Teams* komputerowo wspomagana metrologia i diagnostyka * projektowanie systemów * mikrosystemów i makrosystemów elektronicznych * testowanie i diagnostyka elektroniczna * pomiary właściwości szumowych i zakłóceń * spektroskopia impedancyjna * telemetria i telediagnostyka internetowa * katedra redaguje Metrology and Measurement Systems * kwartalnik PAN znajdujący się na liście JCR
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New method using bilinear transformation for parameter identification ofanticorossion coatings.
PublicationArtykuł przedstawia nową metodę diagnostyki powłok antykorozyjnych z wykorzystaniem przekształcenia biliniowego. Możliwa jest identyfikacja parametrów schematu zastępczego powłoki na podstawie pomiaru impedancji obiektu na kilku, optymalnie dobranych częstotliwościach pomiarowych. Podano zasady doboru optymalnych częstotliwości pomiarowych. Ich liczba jest równa liczbie elementów schematu zastępczego. Opracowany algorytm identyfikacji...
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Rigorous Modal Analysis of Structures Containing Inhomogeneous Dielectric Cylinders.
PublicationW pracy wykorzystano zmodyfikowaną procedurę iteracyjną i metodę dopasowania rodzajów w celu analizy struktur zawierających asymetrycznie umieszczone, niepełnej wysokości lub wielowarstwowe, niejednorodne, cylindryczne rezonatory dielektryczne. Analiza bazuje na nowatorskiej koncepcji zwanej hybrydową macierzą impedancyjną (HIM - hybryd impedancje matrix), która opisuje relacje pomiędzy całkowitym polem elektrycznym i magnetycznym...
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WŁAŚCIWOŚCI ELEKTRYCZNE SZKIEŁ TLENKOWYCH ZAWIERAJĄCYCH Fe2O3
PublicationZbadano właściwości elektryczne szkieł krzemianowo – ołowiowo - żelazowych. Szkła tlenkowe zawierające jony żelaza mogą potencjalnie wykazywać przewodnictwo polaronowe. Celem niniejszej pracy było bliższe określenie zachodzącego w nich mechanizmu przewodnictwa. Wytworzono szkła o składzie dobranym na podstawie ich zakresu szklenia: (50 – 0.5x)[SiO2, PbO] - xFe2O3 gdzie x wynosił odpowiednio 2, 5, 10, 15, 20 i 25 (w % mol). Otrzymane...
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Determination of Mathematical Model Parameters of a Medium Frequency Transformer
PublicationThe paper presents the results of experimental studies of the medium frequency transformer. The object of the research was a prototype of a single-phase transformer with a core made of ferrite I-core elements and windings made of Litz conductors. The research was carried out to determine the parameters of the transformer's mathematical model. The scope of the tests included determining the magnetic hysteresis loop and measuring...
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Left-handed propagation characteristics of a dielectric and metal-loaded periodic circular waveguide
PublicationIn this paper, a periodic dielectric/metallic rod is located in a circular waveguide to obtain left-handed operation. Two geometries of the dielectric/metallic rod are proposed and examined. The dispersion characteristics of the investigated waveguides are obtained using a surface impedance model. Moreover, equivalent circuit models are proposed allowing for calculation of the dispersion characteristics and scattering parameters...