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Search results for: DISEASES , WAVELET TRANSFORMS , WAVELET ANALYSIS , GASTROINTESTINAL TRACT , ESOPHAGUS , SENSITIVITY , IMPEDANCE MEASUREMENT
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An analysis of a measurement probe for a high impedance spectroscopy analyzer
PublicationW artykule przedstawiono sondę będącą obwodem wejściowym analizatora do spektroskopii wysokoimpedancyjnej. Sonda umożliwia pomiar impedancji jednym zaciskiem uziemnionej w zakresie od 100ohm do 100Gohm. Sonda umożliwia wydzielenie dwóch sygnałów proporcjonalnych do prądu i napięcia na impedancji mierzonej w szerokim zakresie częstotliwości od 100uHz do 100MHz.Przeprowadzono analizę sondy w której uwzględniono najważniejsze czynniki...
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An analysis of a measurement probe for a high impedance spectroscopy analyzer
PublicationW artykule przedstawiono sondę będącą obwodem wejściowym analizatora do spektroskopii wysokoimpedancyjnej. Sonda umożliwia pomiar impedancji jednym zaciskiem uziemnionej w zakresie od 100ohm do 100Gohm. Sonda umożliwia wydzielenie dwóch sygnałów proporcjonalnych do prądu i napięcia na impedancji mierzonej w szerokim zakresie częstotliwosci od 100uHz do 100MHz.Przeprowadzono analizę sondy w której uwzględniono najważniejsze czynniki...
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Diagnostic system of cylindrical shell based on experimental modes and wavelet analysis
PublicationArtykuł poświęcony jest technice lokalizacji uszkodzeń w powłoce cylindrycznej. Na podstawie eksperymentalnie wyznaczonych postaci drgań oraz analizy falkowej wyznaczono miejsce uszkodzenia. Przedstawiono algorytm poszukiwania uszkodzeń poprzez zastosowanie sztycznej sieci neuronowej.
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Investigation of Anti-Lock Braking System failures using wavelet analysis
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Neuro-wavelet damage detection technique in beam, plate and shell structures with experimental validation
PublicationNiniejsza praca poświęcona jest technice diagnostyki konstrukcji bazującej na transfor-macie falkowej oraz sztucznych sieciach neuronowych (tzw. system neuro-wavelet). Zastosowanie analizy falkowej pozwala na lokalizację uszkodzeń wymagającą mini-malnej ilości danych wejściowych. W tym celu niezbędna jest tylko odpowiedź kon-strukcji pomierzona w wielu punktach. Poprawę efektywności lokalizacji zniszczeń uzyskano poprzez użycie...
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Electrodes array for contactless ECG measurement of a bathing person - a sensitivity analysis
PublicationAn applicability of a remote (contactless) electrocardiogram (ECG) measurements in a bathtub is presented in the paper. Possibility of ECG measurements in shallowly filled tube with a water was examined. A bathing person was, both, sitting and lying during experiments performed. The problem became non-trivial when the bathing person was moving in reference to a fixed set of electrodes and located at the longer walls of the bathtub....
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Investigation on accelerated impedance spectrum measurement method with multisine signal stimulation
PublicationThe paper presents an investigation on the accelerated impedance spectrum measurement method, oriented at parameter identification of technical objects modelled by a linear equivalent circuit, e.g. anticorrosion coatings.The method is based on multisine signal stimulation of an object and response analysis by triangle window filterbanks.It has several advantages, as compared with conventional point-by-point spectrum measurement....
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Metrology and Measurement Systems
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OPTIMAL WAVELET CHOICE IN ELECTROCHEMICAL EXPERIMENTS
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Optimal wavelet choice in electrochemical experiments
PublicationW ostatnich latach obserwuje się wzrost zainteresowania łączeniem eksperymentów elektrochemicznych z nowoczesnymi technikami analizy sygnałów. Jednym z najbardziej obiecujących kierunków jest analiza falkowa. W omawianym przypadku istnieje wybór pomiędzy różnymi rodzinami falek w zależności od wymogów danego eksperymentu. W pracy omówione zostały wyniki zastosowania różnych typów falek do analizy szumów elektrochemicznych o różnym...
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Wavelet transform-based approach to defect identification in railway carbon contact strips.
PublicationPantographs of electric rail vehicles are fitted with carbon contact strips, which slide along the contact wire of catenary to provide constant electrical contact. Contact strips are exposed to wear and damages. Using damaged contact strips significantly increases the risk of catenary rupture. Therefore, their technical condition has to be inspected frequently. In previous work a 3D laser scanning system was proposed for recording...
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Paweł Burdziakowski dr inż.
PeoplePaweł Burdziakowski, PhD, is a professional in low-altitude aerial photogrammetry and remote sensing, marine and aerial navigation. He is also a licensed flight instructor and software developer. His main areas of interest are digital photogrammetry, navigation of unmanned platforms and unmanned systems, including aerial, surface, underwater. He conducts research in algorithms and methods to improve the quality of spatial measurements...
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Vision-based parking lot occupancy evaluation system using 2D separable discrete wavelet transform
PublicationA simple system for rough estimation of the occupancy of an ad-hoc organized parking lot is presented. A reasonably simple microprocessor hardware with a low resolution monochrome video camera observing the parking lot from the location high above the parking surface is capable of running the proposed 2-D separable discrete wavelet transform (DWT)-based algorithm, reporting the percentage of the observed parking area occupied by...
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Scalable Measurement System for Multiple Impedance Gas Sensors
PublicationAuthor proposes scalable architecture of the measurement system for gas sensor with impedance dependance of the gas concentration. The main part of the system is a single-board impedance analyser. The number of analysers working in parallel can be configured according to specific application. The system is controlled by a single computer which organises the measurement cycle and store the acquired measurement data. The system is...
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Real-Time Bleeding Detection in Gastrointestinal Tract Endoscopic Examinations Video
PublicationThe article presents a novel approach to medical video data analysis and recognition of bleedings. Emphasis has been put on adapting pre-existing algorithms dedicated to the detection of bleedings for real-time usage in a medical doctor’s office during an endoscopic examination. A real-time system for analyzing endoscopic videos has been designed according to the most significant requirements of medical doctors. The main goal of...
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Damage location in beam and plate structures by wavelet analysis of experimentally determined mode shapes
PublicationArtykuł dotyczy zastosowania analizy falkowej do lokalizacji uszkodzeń w konstrukcjach belkowych i płytowych. Wykonano testy dynamiczne belki wspornikowej i płyty utwierdzonej wzdłuż jednej z krawędzi. Lokalizację defektu otrzymano za pomocą transformaty falkowej eksperymentalnie wyznaczonych postaci drgań.
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Damage Detection Using Cointegration Technique and Wavelet Analysis of the Post-Cointegrated Lamb Waves
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Cointegration and wavelet-analysis-based approach for Lamb-wave-based structural damage detection
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An annotated timeline of sensitivity analysis
PublicationThe last half a century has seen spectacular progresses in computing and modelling in a variety of fields, applications, and methodologies. Over the same period, a cross-disciplinary field known as sensitivity analysis has been making its first steps, evolving from the design of experiments for laboratory or field studies, also called ‘in-vivo’, to the so-called experiments ‘in-silico’. Some disciplines were quick to realize the...
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Sensitivity analysis of a composite footbridge
PublicationThis work include an example of sensitivity analysis for the design of a composite footbridge. A sandwich structure is used, consisting two high-strength skins separated by a core material. The analysis was conducted for two numerical models. The first one is a simple, single-span beam of a composite cross-section (laminate and foam), with different Young’s modulus for each material. Calculations were made by means of a MATLAB-based...
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Gut Biofactory—Neurocompetent Metabolites within the Gastrointestinal Tract. A Scoping Review
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Seismic damage diagnosis in adjacent steel and RC MRFs considering pounding effects through improved wavelet-based damage-sensitive feature
PublicationThis paper aims to propose complex Morlet (cmorfb-fc) wavelet-based refined damage-sensitive feature (rDSF) as a new and more precise damage indicator to diagnose seismic damages in adjacent steel and Reinforced Concrete (RC) Moment Resisting Frames (MRFs) assuming pounding conditions using acceleration responses. The considered structures include 6- and 9-story steel and 4- and 8-story RC benchmark MRFs that are assumed to have...
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Application of the wavelet transformation to estimation of intensity of pitting corrosion
PublicationAnalizie poddane zostały dane szumowe odpowiadające korozji wżerowej. Stwierdzona została korelacja pomiędzy intensywnością rejestrowanego szumu a ubytkiem masy elektrod stalowych. Na bazie przekształcenia falkowego zaproponowany został parametr charakteryzujący zaatakowanie wżerowe. Stwierdzono, że z grupy wytypowanych wskaźników prezentowany parametr wskazuje najlepszą korelację z wielkościami ubytków mas elektrod.
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Density smoothness estimation problem using a wavelet approach
PublicationIn this paper we consider a smoothness parameter estimation problem for a density function. The smoothness parameter of a function is defined in terms of Besov spaces. This paper is an extension of recent results (K. Dziedziul, M. Kucharska, B. Wolnik, Estimation of the smoothness parameter ). The construction of the estimator is based on wavelets coefficients. Although we believe that the effective estimation of the smoothness...
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Fault Loop Impedance Measurement in Circuits Fed by UPS and Principle of Safety Protection
PublicationThis paper indicates a significant problem of uncertainty of fault loop impedance (FLI) measurement in circuits powered from uninterruptible power supply (UPS) (double-conversion AC-DC-AC). The correctly determined value of this impedance, related to the short-circuit current disconnection time and to the reference value, is one of the most important elements that determines the approval of an electrical installation and its receivers...
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Evaluation of the fast impedance spectroscopy method in the laboratory measurement system
PublicationIn this paper the method for fast impedancespectroscopy of technical objects with very high impedance(|Zx| ≥ 1 GΩ) is evaluated by means of simulation and practicalexperiment. The method is based on excitation of an object, witha square pulse and measurements of voltage and currentresponses with DAQ card. The object impedance spectrum isobtained with use of continuous Fourier transform. Someimprovements of the method concerned...
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Seismic damage diagnosis in adjacent steel and RC MRFs considering pounding effects through improved wavelet-based damage-sensitive feature
PublicationThis paper aims to propose complex Morlet (cmorfb-fc) wavelet-based refined damage-sensitive feature (rDSF) as a new and more precise damage indicator to diagnose seismic damages in adjacent steel and Reinforced Concrete (RC) Moment Resisting Frames (MRFs) assuming pounding conditions using acceleration responses. The considered structures include 6- and 9-story steel and 4- and 8-story RC benchmark...
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The aberrant overexpression of vimentin is linked to a more aggressive status in tumours of the gastrointestinal tract
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Polynomial analysis as a new way of describing dynamic impedance spectra – Differential and relative impedance spectra
PublicationModel measurements of an equivalent electrical system were carried out using the technique of Dynamic Electrochemical Impedance Spectroscopy. The measurement took the form of potentiodynamic changes imposed on the tested system. Using the possibility of continuous impedance measurements, an attempt was made to develop an original and innovative method of analyzing impedance spectrograms, which is termed polynomial analysis. As...
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A Comprehensive Analysis of Impedance of the Electrochemical Cell
PublicationA comprehensive impedance characteristics of two electrodes electrochemical cell has been pre sented. In this method a multisinusoidal current excitation signal is used. The change of potential of both the electrodes are all registered as a function of time. The proposed method gives the possibility of determining the impedance of both electrodes individually as well as the impedance of a twoelectrode system. Additional application...
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A method of earth fault loop impedance measurement without unwanted tripping of RCDs
PublicationIn low-voltage networks, earth fault loop impedance (EFLI) measurement is the basis for assessing the effectiveness of automatic disconnection of supply. Such a measurement is performed during initial and periodical verification, especially in a TN low-voltage network. Nowadays, due to widespread application of residual current devices (RCDs), such test is difficult in many circuits because RCDs operate during the test. In this...
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Impedance Spectra of RC Model as a Result of Testing Pulse Excitation Measurement Method Dataset
PublicationThe dataset titled Impedance spectra of RC model as a result of testing pulse excitation measurement method contains the impedance spectrum of an exemplary test RC model obtained using pulse excitation. The dataset allows presentation of the accuracy of the impedance spectroscopy measuring instrument, which uses the pulse excitation method to shorten the time of the whole spectrum acquisition.
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Polynomial description of dynamic impedance spectrogram—introduction to a new impedance analysis method
PublicationThis paper presents a polynomial description of spectrograms obtained using Dynamic Electrochemical Impedance Spectroscopy. A method to fit the polynomial degree correctly is discussed. A simple electrical system of a diode connected in parallel with a capacitor was used for testing. Dynamic impedance measurements during potentiodynamic polarization were conducted. This paper presents an alternative analysis method that allows...
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Method of earth fault loop impedance measurement without nuisance tripping of RCDs in 3-phase low-voltage circuits
PublicationVerification of electrical safety in low-voltage power systems includes the measurement of earth fault loop impedance. This measurement is performed to verify the effectiveness of protection against indirect contact. The widespread classic methods and meters use a relatively high value of the measuring current (5–20) A, so that they are a source of nuisance tripping of residual current devices (RCDs). The meters dedicated to circuits...
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Analysis of thoracic regional impedance changes using PCA approach
PublicationA multichannel impedance and one lead electrocardiographic recording system has been developed. The impedance measurement unit is built using a four-electrode technique. It consists of a sinusoidal, 40 kHz, current source and five measurement channels. Circumferential current electrodes have been located at a neck and an abdomen. Voltagemeasurement disk electrodes formed five two-electrode measurement ports. The impedance change...
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Guided waves in steel rails - experimental works and wavelet signal processing
PublicationW artykule zaprezentowano analizę falkową pomierzonych eksperymentalnie fal sprężystych wzbudzanych w szynach kolejowych.
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Damage detection in rectangular plates by continuous two-dimensional wavelet transform
PublicationPraca opisuje zastosowanie dwuwymiarowej transformaty falkowej do detekcji i lokalizacji uszkodzeń w konstrukcji płytowej. Defekt zlokalizowano na podstawie postaci drgań z symulacji numerycznych oraz z badań eksperymentalnych.
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Guided Waves in Steel Rails – Experimental Works and Wavelet Signal Processing
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Damage detection in beams using wavelet transform on higher vibration modes
PublicationNiniejsza praca poświęcona jest technice diagnostyki konstrukcji bazującej na transformacie falkowej. Badany obiekt to belka wspornikowa z uszkodzeniami w formie nacięcia o głębokości 20%, 10% oraz 5% wysokości belki. Pomiary postaci drgań wykonano za pomocą nowoczesnego wibrometru laserowego. Celem pracy jest przedstawienie eksperymentalnych i numerycznych analiz wpływu wyższych postaci drgań na efektywność wykrywania uszkodzeń...
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Harmonic Analysis
Open Research DataWe 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...
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Evaluation of applicability of classic methods of a fault loop impedance measurement to circuits with residual current devices
PublicationMeasurement of fault loop impedance in low voltage grids and systems is in most cases performed to verify the effectiveness of protection against electric shock by automatic disconnection of supply. For the sake of measurement accuracy, it is advisable to perform it using large current. Unfortunately, in circuits with residual current devices which are very widely used nowadays, a large measurement current may trigger those devices...
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Ellipse-fitting algorithm implementation in the impedance measurement system based on DAQ card with FPGA
PublicationThe paper presents an implementation of the ellipse-fitting algorithm in the impedance measurement system based on DAQ card equipped with FPGA chip. The method implementation was tested by simulation means as well as experimentally in the designed and presented measurement system. Finally, the limit values of sampling parameters which assures satisfying accuracy were given.
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Opitmalising Human Development Index with sensitivity analysis
PublicationResearch background: Composite indicators are commonly used not only to measure economic development, the standard of livin g, competitiveness, fairness, effectiveness but are also willingly implemented in to many different fields. How- ever, it seems that in most cases the variable weig hting procedure is avoided or erroneous since in most cases so-called “wights by belief” are...
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The loop impedance measurement
Open Research DataThe loop impedance measurement
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Sensitivity analysis of critical forces of trusses with side bracing
PublicationThe present research is devoted to the study of out-of-plane buckling of trusses with elastic side bracing. Inthis paper, a sensitivity analysis of critical buckling loads of a truss due to bracing stiffness is carried out. A method based on the sensitivity analysis for the determination of the threshold bracing stiffness conditionfor full bracing of a truss is proposed. The influence lines of the unit change of the bracing stiffness...
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Urine headspace analysis in medical diagnostics
PublicationThe analysis of the volatile organic compounds in the bodily fluids such as urine may provide useful information on the patients’ general health. The potential application of urine headspace analysis could facilitate the diagnostics of various diseases such as metabolic disorders, urinary tract diseases and gastrointestinal conditions. Described in this paper are the currently available techniques of urine sample analysis as well...
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Numerical simulation of damage detection in rectangular plate by two-dimensional wavelet transform.
PublicationW pracy przedstawiono metodę lokalizacji pęknięć w płytach przy zastosowaniu transformaty falkowej.
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Multi-Label Classification for AIS Data Anomaly Detection Using Wavelet Transform
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Compressible gas density measurement by means of Fourier analysis of interferograms
PublicationThis paper describes a method for nonintrusive compressible gas density measurement by means of automated analysis of interferograms using FFT (Fast Fourier Transform), and its implementation using DFT (Discrete Fourier Transform), that does make this measurement technique a fairly valuable and accessible experimental method. The presented approach makes it possible to use the finite fringe setting of the interferometer, thus reducing...
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Sensitivity analysis in design process of sandwich U-shaped composite footbridge
PublicationThe structure of the sandwich composite footbridge of a 14 metre span length and U-shaped cross-section was analysed. Sensitivity analysis was performed to support the design process of this innovative object. Linear discrete sensitivity analysis was performed by means of finite element method. The influence of vari-ation of several design variables i.e. thicknesses of inner and outer laminates on the mid-span deflection, as-sumed...