Search results for: harmonic analysis

• Corrosion monitoring by harmonic analysis in aqueous environments

  Publication

  • J. Orlikowski
  • S. Łubiński
  • P. Żuchowski

  - Ochrona przed Korozją - Year 2013

  This paper presents tests concerning the rate of corrosion in non-alloy steel (type S235JR) in an aqueous environment, with an additive of sodium chloride by means of polarization resistance measurements and harmonic analysis. The tests have been carried out for steel samples exposed to the testing environment for six weeks, in order to obtain a constant rate of corrosion in the function of time. The measurements have aimed at...

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• Harmonic Analysis Of Electrochemical and Corrosion Systems - A Review

  Publication

  • K. Darowicki
  • J. Majewska

  - CORROSION REVIEWS - Year 1999

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• APPLIED AND COMPUTATIONAL HARMONIC ANALYSIS

  Journals

  ISSN: 1063-5203 , eISSN: 1096-603X

• The application of Gabor transformation in the harmonic analysis of corrosion processes

  Publication

  • K. Darowicki
  • A. Krakowiak
  • K. Darowicki

  - ANTI-CORROSION METHODS AND MATERIALS - Year 2003

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• The application of Gabor transformation in the harmonic analysis of corrosion processes.

  Publication

  • K. Darowicki
  • A. Krakowiak

  - ANTI-CORROSION METHODS AND MATERIALS - Year 2003

  Zaproponowana została nowa metoda analizy widmowej niestacjonarnych procesów korozyjnych. Analizie poddany został układ modelujący pierwszorzędową reakcję elektrodową. Wykazano, że w przypadku pobudzenia układu liniowo zmieniającym się potencjałem z nałożoną składową sinusoidalną przekształcenie Fouriera nie odzwierciedla zmian amplitudy powstających składowych harmonicznych. Jako rozwiązanie zaproponowana została analiza...

• Harmonic Analysis

  Open Research Data

  open access

  • K. Dziedziul

  We construct a decomposition of the identity operator on a Riemannian manifold M as   a sum of smooth orthogonal projections subordinate to an open cover of M. This extends a decomposition on the real line by smooth orthogonal projection due to Coifman and Meyer (C. R. Acad. Sci. Paris, Sér. I Math., 312(3), 259–261 1991) and Auscher, Weiss, Wickerhauser...

• Application of higher order spectra in harmonic analysis of corrosion process

  Publication

  • A. Zieliński

  - Physico-Chemical Mechanics of Materials - Year 2006

  Zjawiska nieliniowe są niezwykle często spotykane w praktyce badań elektrochemicznych i korozyjnych. Typowym przykładem są procesy elektrodowe kontrolowane szybkością przeniesienia ładunku. Często stosowanym w takich przypadkach podejściem jest aproksymacja fragmentu krzywej prąd-napięcie za pomocą charakterystyki liniowej. W niniejszej pracy autorzy prezentują możliwość wykorzystania pomiarów składowych harmonicznych do oceny...

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• Modelling of a 25 kV-50 Hz Railway Infrastructure for Harmonic Analysis

  Publication

  • C. Stackler
  • F. Morel
  • P. Ladoux
  • P. Dworakowski

  - European Journal of Electrical Engineering - Year 2020

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• Digital harmonic analysis of cadmium ion reduction on a dropping mercury electrode

  Publication

  • K. Darowicki
  • A. Krakowiak

  - RUSSIAN JOURNAL OF ELECTROCHEMISTRY - Year 2003

  Badano redukcję jonów kadmu na rtęciowej elektrodzie kroplowej. Jako pobudzenie zastosowano sinusoidalny sygnał napięciowy nałożony na liniowo zmieniający się potencjał dc. Przeprowadzono analizę czasowo-częstotliwościową prądu polarograficznego dla reakcji redukcji jonu kadmu na rtęciowej elektrodzie kroplowej. Klasyczna transformacja Fouriera prowadzi do dekompozycji prądu polarograficznego na składowe harmoniczne. Harmoniczne...

• Harmonic analysis of the current of an electric system simulating the electrode process in conditions of linearly changing potential

  Publication

  • K. Darowicki
  • A. Krakowiak

  - INSTRUMENTATION SCIENCE & TECHNOLOGY - Year 2002

  Analizowany był prąd elektrycznego modelu symulującego pierwszorzędową reakcję elektrodową zachodzącą w warunkach liniowo zmieniającego się potencjału z nałożonym sygnałem sinusoidalnym. Pokazano, że transformacja Fouriera nie odzwierciedla zmian amplitudy składowych komponentów w funkcji potencjału. Także matematycznie wykazano, że zastosowanie transformacji Gabora do analizy spektralnej pozwala uzyskać poprawną dekompozycję częstotliwościową....

• The effect of a polyharmonic structure of the perturbation signal on the results of harmonic analysis of the current of a first-order electrode reaction

  Publication

  • K. Darowicki
  • J. Majewska
  • K. Darowicki

  - ELECTROCHIMICA ACTA - Year 1998

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• Application of the Harmonic Balance Method for Spatial Harmonic Interactions Analysis in Axial Flux PM Generators

  Publication

  • N. Radwan-Pragłowska
  • T. Węgiel
  • D. Borkowski
  • T. Wegiel

  - ENERGIES - Year 2021

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• Improving AFM images with harmonic interference by spectral analysis

  Publication

  • M. Kiwilszo
  • A. Zieliński
  • J. Smulko
  • K. Darowicki

  - MICROSCOPY AND MICROANALYSIS - Year 2012

  Przedstawiono sposób usunięcia zakłóceń pojawiających się na obrazach uzyskiwanych z mikroskopu sił atomowych (AFM). Przybliżono kilka metod stosowanych do redukcji zakłóceń w obrazach. Następnie opisano zidentyfikowane zakłócenia harmoniczne oraz zaproponowany sposób ich znaczącej redukcji. W pracy zamieszczono szereg obrazów uzyskanych z mikroskopu AFM ilustrujących efekty powodowane zakłóceniami oraz skuteczność zaproponowanej...

• Corrosion behaviour of low carbon steel in artificial seawater using TP, LP, EIS, Harmonic Analysis (HA) and new method Dynamic Electrochemical Impedance Spectroscopy (DEIS)

  Publication

  • K. Darowicki
  • H. Gerengi
  • G. Bereket
  • P. Ślepski
  • A. Zieliński

  - Journal of Corrosion Science and Engineering - Year 2007

  Ze względu na istotną rolę technik elektrochemicznych w badaniach procesów korozyjnych są one szeroko stosowane w monitorowaniu korozji. Celem niniejszej pracy jest zgromadzenie rezultatów wyników doświadczalnych uzyskanych różnymi technikami i znalezienie korelacji między nimi. Własności korozyjne stali stopowej (AISI 1026) w sztucznej wodzie morskiej zostały zbadane z wykorzystaniem ekstrapolacji tafelowskiej (TP), polaryzacji...

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• Determination of Local Corrosion Current from Individual Harmonic Components

  Publication

  • Ł. Burczyk
  • K. Darowicki

  - JOURNAL OF THE ELECTROCHEMICAL SOCIETY - Year 2017

  Harmonic analysis has been used in corrosion measurements for several decades. During this period the method has been refined and developed. Nevertheless, the technique has not been applied to properties determination in local scale yet. This paper is focused on local corrosion current measurements based on harmonic analysis. For this purpose, a non-linear nature of electrode processes is used and measured in local scale applying...

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• Sensorless Disturbance Detection for Five Phase Induction Motor with Third Harmonic Injection

  Publication

  • P. Strankowski
  • J. Guziński
  • M. Morawiec
  • A. Lewicki
  • F. Wilczyński

  - Year 2017

  The paper presents a sensorless disturbance detection procedure that was done on a five phase induction motor with third harmonic injection. A test bench was developed where a three phase machine serves as disturbance generator of different frequencies. The control of the machines is based on multi scalar variables that ensures an independent control of the motor EMF and the rotor flux. For disturbance identification a speed observer...

• The influence of the motor filtrers on harmonic current emmision in the pro-ective connection of drive systems.

  Publication

  • M. Olesz
  • S. Witkowski

  - Year 2003

  This paper contains detailed analysis of currents in protective wire in engine supplied from frequency converter without any external filters added. It was found that the peak value of current in protective conductor of engine was about 1500 mA at frequencies 5 Hz 50 Hz. In the continuation of research the dU/dt type motor filter and the sinusoidal filter were tested. It was found that the current in protective wire decreased...

• Optimized Space Vector Modulation strategy for five phase voltage source inverter with third harmonic injection

  Publication

  • A. Lewicki
  • P. Strankowski
  • M. Morawiec
  • J. Guziński

  - Year 2017

  This paper presents a simple and an effective SVM algorithm for five-phase Voltage-Source Inverters with the possibility to control independently the voltage vectors for fundamental and auxiliary orthogonal subspaces. The essential benefit is that output voltage is generated using only four active voltage vectors with limited numbers of switching. In the proposed solution, four active vectors are arbitrary chosen, independent of...

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• Comparative Analysis of Reactive Power Compensation Devices in a Real Electric Substation

  Publication

  • H. Tariq
  • S. Czapp
  • S. Tariq
  • K. M. Cheema
  • A. Hussain
  • A. H. Milyani
  • S. Alghamdi
  • Z. M. S. Elbarbary

  - ENERGIES - Year 2022

  A constant worldwide growing load stress over a power system compelled the practice of a reactive power injection to ensure an efficient power network. For this purpose, multiple technologies exist in the knowledge market out of which this paper emphasizes the usage of the flexible alternating current transmission system (FACTS) and presents a comparative study of the static var compensator (SVC) with the static synchronous compensator...

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• Kinetic analysis of the stage for a high speed steam turbine

  Publication

  • D. Sławiński
  • W. Zakrzewski

  - Transactions of the Institute of Fluid-Flow Machinery - Year 2012

  This article analyzes possibilites of resonances within a control stage for a high speed steam turbine. This stage hase been based on assembling of a single blade to a rotating disk and increasing of rigidity of the system by using of a bandage. In the analysis will be nd a possiblity of resonance frequency, and mistuning by showing safety working ranges. The calculations have bean used the3D modal and harmonic analysis by the...

• Corrosion process monitoring by AFM higher harmonic imaging

  Publication

  • S. Babicz-Kiewlicz
  • A. Zieliński
  • J. Smulko
  • K. Darowicki

  - MEASUREMENT SCIENCE & TECHNOLOGY - Year 2017

  The atomic force microscope (AFM) was invented in 1986 as an alternative to the scanning tunnelling microscope, which cannot be used in studies of non-conductive materials. Today the AFM is a powerful, versatile and fundamental tool for visualizing and studying the morphology of material surfaces. Moreover, additional information for some materials can be recovered by analysing the AFM's higher cantilever modes when the cantilever...

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• Application of harmonic techniques to evaluation of pitting corrosion

  Publication

  • S. Krakowiak
  • P. Ślepski
  • A. Krakowiak

  - Physico-Chemical Mechanics of Materials - Year 2002

  Przedstawiono próbę zastosowania metod zmiennoprądowych do oceny podatności na korozję wżerową stali stopowych. Na sygnał stałoprądowy nałożono sinusoidę o częstotliwości 10 Hz. Dzięki jednoczesnej, cyfrowej rejestracji sygnału pobudzenia i odpowiedzi układu badanego otrzymano ciągłe zmiany modułu impedancji i modułu pojemności w trakcie klasycznej cyklicznej polaryzacji. Na podstawie jednego eksperymentu istnieje możliwość wyznaczenia...

• Fermionized Dipolar Bosons Trapped in a Harmonic Trap

  Publication

  • P. Kościk

  - FEW-BODY SYSTEMS - Year 2017

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• Selective Harmonic Elimination PWM For a Cascaded Multi-level Inverter

  Publication

  • A. L. Kouzou
  • A. Krama
  • S. S. Refaat
  • H. Abu-Rub

  - Year 2020

  This paper deals with the selective harmonic elimination pulse width modulation (SHE-PWM) technique. This technique is used for the elimination of selected dominant low order harmonics in the multi-level inverter output voltage. The presence of these harmonics is the essential drawback of such kind of inverters; especially when it is used for the control of different AC drivers. The SHE-PWM is based...

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• Quality assessment of high voltage varistors by third harmonic index

  Publication

  • L. Hasse
  • J. Smulko

  - Metrology and Measurement Systems - Year 2008

  High voltage varistors that consist of grained ZnO have to be tested before assembling into a surge arrester. The existing methods demand a usage of high voltages and intensive currents that is inconvenient, destructive and needs extensive power consumption. Additionally, these methods require metallization of the prepared varistor structures that increases costs. We propose another method of varistors quality assessments by a...

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• Third harmonic index as a diagnostic tool of high-voltage varistors

  Publication

  • L. Hasse
  • J. Smulko
  • L. Spiralski

  - Year 2008

  The recommended methods for standard testing of high-voltage varistors demand application of high voltages and intensive currents that is inconvenient and needs extensive power consumption. These methods require metallization of the prepared ZnO structures that increases costs of testing. Another method of varistor quality and endurance evaluation by the third harmonic index measurement at relatively low voltage range has been...

• Stability Analysis of Shunt Active Power Filter with Predictive Closed-Loop Control of Supply Current

  Publication

  • A. Bielecka
  • D. Wojciechowski

  - ENERGIES - Year 2021

  This 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...

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• Frequency dispersion of harmonic components of the current of an electrode process

  Publication

  • K. Darowicki
  • K. Darowicki

  - JOURNAL OF ELECTROANALYTICAL CHEMISTRY - Year 1995

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• Fundamental-harmonic impedance of first-order electrode reactions

  Publication

  • K. Darowicki

  - ELECTROCHIMICA ACTA - Year 1994

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• Quantum Correlations of a Few Bosons within a Harmonic Trap

  Publication

  • P. Kościk

  - FEW-BODY SYSTEMS - Year 2012

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• Dependence of harmonic generation on primary wave pressure distribution

  Publication

  • A. Baranowska

  - Archives of Acoustics - Year 2007

  Praca dotyczy numerycznego badania zagadnienia wytwarzania harmonicznych ciśnienia podczas rozchodzenia się fal o skończonej amplitudzie, promieniowanych przez źródła kołowe o różnych rozkładach. Model matematyczny zbudowano w oparciu o równanie KZK. Do numerycznego rozwiązania problemu zastosowano metodę bilansu harmonicznych i metodę różnic skończonych. Analizowano zmiany składowych harmonicznych ciśnienia w obrębie wiązki akustycznej....

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• Entropy of water calculated from harmonic approximation: estimation of the accuracy of method

  Publication

  • J. Zielkiewicz

  - JOURNAL OF CHEMICAL PHYSICS - Year 2008

  Some molecular dynamics simulations were performed for liquid TIP4P and SPC water at a constant density (1.00 g/cm(3)) and within the temperature range of 5-90 degrees C. By using harmonic approximation, both the entropy of water S-H and the specific heat c(v) were calculated, and the results were compared to literature data. It was found that harmonic approximation overestimates absolute entropy of TIP4P water by 5.6 J/mol K (similar...

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• Mode vibrations of plates – experimental analysis

  Publication

  • A. D. Kaczmarek-Penia•kova
  • L. Javorek
  • K. Orłowski

  - Annals of WULS, Forestry and Wood Technology - Year 2014

  In this paper results of the square MDF plate and circular saw blades examination with the use of the harmonic method to static identification of resonant frequencies and shapes of mode vibrations are presented. Obtained results reveled that for circular saws with large holes in a saw blade appeared two resonant frequencies for the same nodal number.

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• Voltage Harmonic Distortion Measurement Issue in Smart-Grid Distribution System

  Publication

  • J. Łuszcz
  • R. Smolenski

  - Year 2012

  This paper presents the investigation results ofvoltage harmonic transfer accuracy problems through voltagetransformers which are widely used in power quality monitoringsystems in medium and high voltage grids. A simplified lumpedparameters circuit model of the voltage transformer is presentedand verified by simulation and experimental investigations. Anumber voltage transformers typically used in medium voltagegrid has been tested...

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• Diagnosis of Damage in a Steel Tank Model by Shaking Table Harmonic Tests

  Publication

  • D. Burkacki
  • R. Jankowski

  - Key Engineering Materials - Year 2012

  The aim of the present paper is to show the results of the shaking table experimental study concerning the diagnosis of damage in a model of cylindrical steel tank with self-supported roof which is filled with liquid. During the tests, the base of the structure was excited under the harmonic loading with variable frequency. The tests were repeated for different stages of damage, which was introduced in the model by easing the bolts...

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• A CMRC-based compact rat-race coupler with harmonic suppression

  Publication

  • A. Bekasiewicz
  • P. Kurgan

  - Year 2013

  In this paper, an eective miniaturization technique exploiting compact microstrip resonant cells has been discussed and experimentally validated on the basis of a 3-dB microstrip rat-race coupler. The application of the method proposed has resulted in 91 % circuit area reduction in comparison to a conventional rat-race coupler. Experimental results show good agreement with theoretical characteristics, as well as an additional eect,...

• Low harmonic multipulse voltage converters using coupled reactors

  Publication

  • R. Strzelecki
  • T. Sak
  • M. Grabarek
  • P. Zolov
  • N. Strzelecka

  - Year 2016

  This paper presents a novel approach to the multi pulse voltage converters (VC), especially voltage source inverters (VSI) and matrix converters (MC) based on several typical identical modules connected in parallel using coupled reactors. Such arrangements resulting in lower voltage distortions at extremely low switching frequency. The proposed arrangement was validated by simulation. Laboratory models of 18- and 24pulse 3-level...

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• Diagnosis of Damage in a Steel Tank Model by Shaking Table Harmonic Tests

  Publication

  • D. Burkacki
  • R. Jankowski

  - Year 2013

  Diagnosis of damage in civil engineering structures has recently become an important issue in the safety assessment procedure. Among a number of different approaches, a method of measuring the changes in natural frequencies is one of the most effective indicators of global damage. It has been successfully applied to relatively small. structures, however, the tests on large structures are very difficult and the practical application...

• Polyarmonic model of synchronous generator for analysis of autonomous power generation systems

  Publication

  • F. Kutt
  • M. Michna
  • M. Ronkowski
  • P. Chrzan

  - Maszyny Elektryczne : zeszyty problemowe - Year 2011

  Abstract: This paper presents the polyharmonic modelling of synchronous generator (SG) in machine variables. The simple geometry and windings physical layout has been used for inductance calculations of a salient-pole SG. The main advantage of this model is the ease of describing an autonomous power generation system (APGS) in terms of its topology and thus providing effective analysis at the static and dynamic states, both for...

• ESTIMATION OF NONSTATIONARY HARMONIC SIGNALS AND ITS APPLICATION TO ACTIVE CONTROL OF MRI NOISE

  Publication

  • M. Niedźwiecki
  • M. Meller
  • Y. Kajikawa
  • D. Łukwiński

  - Year 2013

  A new adaptive comb filtering algorithm, capable of tracking the fundamental frequency and amplitudes of different frequency components of a nonstationary harmonic signal embedded in white measurement noise, is proposed. Frequency tracking characteristics of the new scheme are studied analytically, proving (under Gaussian assumptions and optimal tuning) its statistical efficiency for quasi-linear frequency changes. Laboratory tests...

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• Nonlinear control of five phase induction motor with synchronized third harmonic flux injection

  Publication

  • M. Adamowicz
  • J. Guziński
  • Z. Krzemiński

  - Year 2015

  The paper deals with the novel control system for five phase induction motor (IM) that enables the injection of the rotor flux 3rd harmonic component. Two multiscalar models are transformed from the 1-1 and 2-2 vector models developed in the 1st and 3rd harmonic planes. Based on the obtained multiscalar models the synthesis of dual multiscalar control is established. The obtained two multiscalar control systems can independently...

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• Hysteresis curves and loops for harmonic and impulse perturbations in some non-equilibrium gases

  Publication

  • A. Perelomova

  - CENTRAL EUROPEAN JOURNAL OF PHYSICS - Year 2013

  Evolution of sound in a relaxing gas whose properties vary in the course of wave propagation, is studied. A relaxing medium may reveal normal acoustic properties or be acoustically active. In the first case, losses in acoustic energy lead to an increase in internal energy of a gas similarly as it happens in Newtonian fluids. In the second case, acoustic energy increases in the course of sound propagation, and the internal energy...

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• Errors in the analysis of series resonant inverter/converter assuming sinusoidal waveforms of voltage and current

  Publication

  • J. Mucko
  • R. Strzelecki

  - Year 2016

  In this paper the theory and simulation results of the series resonant inverter / converter are presented. In this work the authors carried out a detailed comparative analysis of results obtained using the method of AC analysis in the steady state for the first harmonic with the results of computer simulation. The AC analysis under certain conditions can lead to errors disqualifying this method. In particular, these errors appear...

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• Corrosion monitoring of selected metals in artificial seawater by harmonic synthesis method

  Publication

  • J. Jankowski

  - Physico-Chemical Mechanics of Materials - Year 2002

  Przedstawiono podstawy teoretyczne nowej metody elektrochemicznej nazwanej metodą syntezy harmonicznej (SH). Metoda jest oparta na pomiarach pierwszych trzech składowych harmonicznych prądu generowanego przez korodującą elektrodę po pobudzeniu sinusoidalnym sygnałem napięciowym bardzo niskiej częstotliwości. Na tej podstawie rekonstruowana jest dyskretna quasi-stacjonarna charakterystyka polaryzacyjna elektrody. Jej analiza numeryczna...

• Detection of Closing Crack in Beam Based on Responses Induced by Harmonic Excitation

  Publication

  • S. A. Tewelde
  • M. Krawczuk

  - SENSORS - Year 2024

  The non-linear contact model was chosen to simulate the closed crack in the cantilever beam. The study examines the shape and characteristics of the phase diagram of a cantilever beam with closed cracks. It investigates how various crack properties influence the geometry of the phase diagram and proposes a method for identifying cracks based on their features. The area of each closed curve in the phase diagram is determined using...

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• Theoretical description of fundamental-harmonic impedance of a two-step electrode reaction

  Publication

  • K. Darowicki

  - ELECTROCHIMICA ACTA - Year 1995

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• Note on the Harmonic Approximation in the Treatment of Entanglement: N Cold Trapped Ions

  Publication

  • P. Kościk
  • R. Maj

  - FEW-BODY SYSTEMS - Year 2014

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• Modelling of Voltage Transformer Performance in Power System Harmonic Frequency Range

  Publication

  • J. Łuszcz
  • I. Mosoń

  - Przegląd Elektrotechniczny - Year 2009

  Zniekształcenia harmoniczne napięć i prądów występujące we współczesnych systemach energetycznych powodują liczne problemy pomiarowe. W referacie przedstawiono analizę właściwości przekładników napięciowych stosowanych w sieciach SN i WN w zakresie częstotliwości mierzonych zniekształceń harmonicznych. Opracowany szerokopasmowy model obwodowy został zweryfikowany symulacyjnie i eksperymentalnie. Wyniki przeprowadzonych badań potwierdzają...

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• Modelling of voltage transformer performance in power system harmonic frequency range

  Publication

  • J. Łuszcz
  • I. Mosoń

  - Year 2008

  Zniekształcenia harmoniczne napięć i prądów występujące we współczesnych systemach energetycznych powodują liczne problemy pomiarowe. W referacie przedstawiono analizę właściwości przekładników napięciowych stosowanych w sieciach SN i WN w zakresie częstotliwości mierzonych zniekształceń harmonicznych. Opracowany szerokopasmowy model obwodowy został zweryfikowany symulacyjnie i eksperymentalnie. Wyniki przeprowadzonych badań potwierdzają...

• The study of harmonic imaging by AFM = Badania harmonicznych w obrazowaniu AFM

  Publication

  • S. Babicz-Kiewlicz

  - Measurement Automation Monitoring - Year 2011

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