Search results for: noise tests - Bridge of Knowledge

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Search results for: noise tests

Search results for: noise tests

  • Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network

    Publication

    - PHYSICAL REVIEW A - Year 2010

    We analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative...

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  • Analysis of Lombard speech using parameterization and the objective quality indicators in noise conditions

    Publication

    - Year 2018

    The aim of the work is to analyze Lombard speech effect in recordings and then modify the speech signal in order to obtain an increase in the improvement of objective speech quality indicators after mixing the useful signal with noise or with an interfering signal. The modifications made to the signal are based on the characteristics of the Lombard speech, and in particular on the effect of increasing the fundamental frequency...

  • LOW NOISE TIRES FOR HYBRID AND ELECTRIC VEHICLES

    Publication

    Low Emission Vehicles that are hybrid and electric cars may benefit from specially designed tires that are optimized for driving conditions typical for such vehicles. It is possible that in the future Low Emission Vehicles, especially passenger cars, will substitute conventional vehicles in all applications, however for the time being they are mostly used in urban and suburban areas. Urban traffic has a rather low demand for grip...

  • Identification of acoustic event of selected noise sources in a long-term environmental monitoring systems

    Publication
    • M. Kłaczyński
    • W. Cioch
    • T. Wszołek
    • W. Wszołek
    • D. Mleczko
    • P. Pawlik
    • A. Grzeczka

    - Year 2014

    ABSTRACT Undertaking long-term acoustic measurements on sites located near an airport is related to a problem of large quantities of recorded data, which very often represents information not related to flight operations. In such areas, usually defined as zone of limited use, often other sources of noise exist, such as roads or railway lines treated is such context as acoustic background. Manual verification of such recorded data...

  • Dynamical description of quantum computing: generic nonlocality of quantumnoise

    Publication

    We develop a dynamical non-Markovian description of quantum computing in the weak-coupling limit, in the lowest-order approximation. We show that the long-range memory of the quantum reservoir (such as the 1/t4 one exhibited by electromagnetic vacuum) produces a strong interrelation between the structure of noise and the quantum algorithm, implying nonlocal attacks of noise. This shows that the implicit assumption of quantum error...

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  • Assessment of Supercapacitor’s Quality by Means of Low Frequency Noise

    Publication

    Low frequency noise is a well-known tool for quality and reliability assessment of electronic devices. This phenomenon is observed in different electrochemical devices as well (e.g., smart windows, electrochemical corrosion processes). Thus, we can assume that the same tool can be used to asses quality of supercapacitors. Their quality is usually determined only by capacitance and/or equivalent series resistance (ESR), or impedance....

  • Suppression of distortions in signals received from Doppler sensor for vehicle speed measurement

    Publication

    - Year 2018

    Doppler sensors are commonly used for movement detection and speed measurement. However, electromagnetic interference and imperfections in sensor construction result in degradation of the signal to noise ratio. As a result, detection of signals reflected from moving objects becomes problematic. The paper proposes an algorithm for reduction of distortions and noise in the signal received from a simple, dual-channel type of a Doppler...

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  • Anatomy of noise in quantitative biological Raman spectroscopy

    Publication
    • J. Smulko
    • N. Chari Dingari
    • J. S. Soares
    • I. Barman

    - BIOANALYSIS - Year 2014

    Raman spectroscopy is a fundamental form of molecular spectroscopy that is widely used to investigate structures and properties of molecules using their vibrational transitions. It relies on inelastic scattering of monochromatic laser light irradiating the specimen. After appropriate filtering the scattered light is dispersed onto a detector to determine the shift from the excitation wavelength, which appears in the form of...

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  • Temperature influence on tyre/road noise on poroelastic road surface based on laboratory measurements

    Publication

    The temperature effect on measured tyre/road noise is very important phenomena as it may lead to significant errors in measurement results due to substantial influence of this parameter on the obtained values. It depends mainly on the particular tyre-road combination. It is different for dense and porous as well as for bituminous and cement concrete pavements. It differs also depending on tested tyre. The correction procedure for...

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  • INFLUENCE OF TEST CONDITIONS ON TYRE/ROAD NOISE MEASURED BY THE DRUM METHOD

    Publication

    Tyre/road noise is one of the most important environmental problems related to road traffic. Nowadays a few standard procedures of tyre/road noise measurements are in use. Unfortunately, measurement conditions specified within relevant standards are very different. For example, procedure described in ISO 11819-2 used for pavement investigations requires tyre load of 3200 N and capped inflation pressure of 200 kPa. At the same time...

  • On the Handling of Outliers in the GNSS Time Series by Means of the Noise and Probability Analysis

    Publication

    - Central European Journal of Geosciences - Year 2015

    The data pre-analysis plays a significant role in the noise determination. The most important issue is to find an optimum criterion for outliers removal, since their existence can affect any further analysis. The noises in the GNSS time series are characterized by spectral index and amplitudes that can be determined with a few different methods. In this research, the Maximum Likelihood Estimation (MLE) was used. The noise amplitudes...

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  • Analysis of radiometric signal in sedimentating suspension flow in open channel

    Publication

    - Year 2014

    The article discusses issues related to the estimation of the sedimentating solid particles average flow velocity in an open channel using radiometric methods. Due to the composition of the compound, which formed water and diatomite, received data have a very weak signal to noise ratio. In the process analysis the known determining of the solid phase transportation time delay the classical cross-correlation function is the most...

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  • Propagation of Ship-Generated Noise in Shallow Sea

    Contamination of sea environment by noise and any energy radiated to water constitutes today a problem to which more and more attention is paid, in view, a.o., of consequences of an impact of these factors onto marine fauna. European Union has introduced a directive by which EU countries are made responsible to undertake efforts aimed at reaching a good envirenmental status of European seas by 2020. A main source of underwater...

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  • Error analysis for European IGS stations

    Publication

    - STUDIA GEOPHYSICA ET GEODAETICA - Year 2016

    Each of the GPS time series that describes the changes of topocentric components consists of a deterministic and a stochastic part, whose character influences the errors of the deterministic parameters. As to the uncertainties of reliable velocities of permanent satellite station systems, surveys that estimate and take into account any dependencies that may affect subsequent operational efficiency are very important. For this analysis,...

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  • Areas of Fan Research—A Review of the Literature in Terms of Improving Operating Efficiency and Reducing Noise Emissions

    Publication

    Fans as industrial devices are among the most significant single recipients of driving energy. Therefore, they represent an important area of energy savings to reduce CO2 emissions. The ubiquity of fans and their operation under conditions different from the optimum provides an opportunity for more significant global reductions in the energy used to drive them. The second important aspect, besides energy efficiency, related to...

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  • A High-Efficient Measurement System With Optimization Feature for Prototype CMOS Image Sensors

    In this paper, a gray-scale CMOS image sensor (CIS) characterization system with an optimization feature has been proposed. By using a very fast and precise control of light intensity, based on the pulsewidth-modulation method, it is avoided to measure the illuminance every time. These features accelerate the multicriteria CIS optimization requiring many thousands of measurements. The system throughput is 2.5 Gb/s, which allows...

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  • Reduction of noise and rolling resistance by horizontal grinding of asphalt pavements

    Publication

    - Year 2015

    Grinding of cement concrete pavements to reduce unevenness and noise is common since a long time. Grinding is then made with wheels equipped with diamond blades rotating in the vertical plane. This creates narrow vertical/longitudinal grooves in the pavement. It is not applied to asphalt pavements. In this paper an alternative type of grinding is studied. In this case plates with diamond heads rotate in the same plane as the pavement,...

  • Gas selectivity enhancement by sampling-and-hold method in resistive gas sensors

    Publication

    Commercial resistive gas sensors exhibit various sensitivity to numerous gases when working at different elevated temperatures. That effect is due to a change in velocity of adsorption and desorption processes which can be modulated by temperature. Thus, to reach better selectivity of gas detection, we propose to apply a known method (called the sampling-and-hold method) of cooling down the gas sensor in the presence of the investigated...

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  • Comparative analysis of spectral and cepstral feature extraction techniques for phoneme modelling

    Publication

    - Year 2018

    Phoneme parameter extraction framework based on spectral and cepstral parameters is proposed. Using this framework, the phoneme signal is divided into frames and Hamming window is used. The performances are evaluated for recognition of Lithuanian vowel and semivowel phonemes. Different feature sets without noise as well as at different level of noise are considered. Two classical machine learning methods (Naive Bayes and Support...

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  • APPLICATION OF THE HIGH FREQUENCY LINEARIZATION OF THE EAR IN PATIENTS WITH TINNITUS . Metoda linearyzacji narządu słuchu u osób cierpiących z szumami usznymi

    Publication

    - Year 2013

    This paper summarises the problem of tinnitus, hypotheses on its causes and the treatment methods. Moreover, a hypothesis on tinnitus origins is explained, based on the mechanisms of the analog-to-digital conversion and quantization. In addition, this paper describes methods of determining the acoustic intensity and spectra of low- level ultrasonic signals, as well as impedance characteristics of an ultrasound transducer. Furthermore,...

  • Application of TMS320c67xx signal processors for SONIC-self-optimizing narrowband interference canceler

    Publication

    - Year 2010

    The paper presents a laboratory system for testing active control algorithms of acoustics noise in ducts. An applied algorithm - self-optimizing narrowband interference canceller (SONIC), allows one to remove narrowband disturbances of constant or slowly time-varying frequencies. Example experimental results of using the laboratory system for supression of sinusoidal disturbance are described. An electronic part of the system was...

  • Time-Gating method with automatic calibration for accurate measurements of electrically small antenna radiation patterns in Non-Anechoic environments

    Publication

    Non-anechoic sites represent a cheap alternative to measurements of antennas in dedicated facilities. However, due to a high noise—from the external EM signal sources and multipath interferences—the quality of radiation patterns obtained in non-anechoic conditions is poor. The characteristics can be corrected using a time-gating method (TGM), which involves filtering of the noise based on temporal analysis of the measured signals....

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  • BP-EVD: Forward Block-Output Propagation for Efficient Video Denoising

    Denoising videos in real-time is critical in many applications, including robotics and medicine, where varying light conditions, miniaturized sensors, and optics can substantially compromise image quality. This work proposes the first video denoising method based on a deep neural network that achieves state-of-the-art performance on dynamic scenes while running in real-time on VGA video resolution with no frame latency. The backbone...

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  • Performance Analysis of the "Intelligent" Kirchhoff- Law - Johnson-Noise Secure Key Exchange

    Publication

    The Kirchhoff-law - Johnson-noise (KLJN) secure key distribution system provides a way of exchanging theoretically secure keys by measuring random voltage and current through the wire connecting two different resistors at Alice’s and Bob’s ends. Recently new advanced protocols for the KLJN method have been proposed with enhanced performance. In this paper, we analyze the KLJN system and compare with the „intelligent” KLJN (iKLJN)...

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  • ANN for human pose estimation in low resolution depth images

    Publication

    - Year 2017

    The paper presents an approach to localize human body joints in 3D coordinates based on a single low resolution depth image. First a framework to generate a database of 80k realistic depth images from a 3D body model is described. Then data preprocessing and normalization procedure, and DNN and MLP artificial neural networks architectures and training are presented. The robustness against camera distance and image noise is analysed....

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  • Degradation of reference tyres used for CPX measurements

    Measurements of tyre/road noise using the Close Proximity Method are based on reference tyres that are described in ISO/TS 11819-3. The standard specifies two tyres, namely "P1" and "H1" that should be used during measurements. To be used for measurements each tyre must fulfill certain conditions that are listed in the standard. The conditions are related to the tread pattern depth and rubber hardness. During experiments performed...

  • Elastic waves in the railroad track substructures and its surroundings analyzed with non-classical operational methods

    Publication

    We analyze the propagation of the waves generated by the rolling stock and the interaction of those waves on the medium and its surroundings. We use non-classical operational methods for monitoring construction of the railway infrastructure and for noise damping.

  • Automatic sound recognition for security purposes

    Publication

    - Year 2008

    In the paper an automatic sound recognition system is presented. It forms a part of a bigger security system developed in order to monitor outdoor places for non-typical audio-visual events. The analyzed audio signal is being recorded from a microphone mounted in an outdoor place thus a non stationary noise of a significant energy is present in it. In the paper an especially designed algorithm for outdoor noise reduction is presented,...

  • Multiacces quantum communication and product higher rank numerical range

    Publication

    In the present paper we initiate the study of the product higher rank numerical range. The latter, being a variant of the higher rank numerical range, is a natural tool for study- ing a construction of quantum error correction codes for multiple access channels. We review properties of this set and relate it to other numerical ranges, which were recently introduced in the literature. Further, the concept is applied to the construction...

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  • Localization of impulsive disturbances in archive audio signals using predictive matched filtering

    Publication

    The problem of elimination of impulsive disturbances from archive audio signals is considered and its new solution, called predictive matched filtering, is proposed. The new approach is based on the observation that a large percentage of noise pulses corrupting archive audio recordings have highly repetitive shapes that match several typical “patterns”, called click templates. To localize noise pulses, click templates can be correlated...

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  • Rolling Resistance And Tire/Road Noise on Rubberized Asphalt Pavement In Poland

    Publication

    The paper presents results of tire/road noise and rolling resistance measurements performed on stone-matrix asphalt (SMA) that contains rubberized asphalt developed and produced by the company in Poland. Bituminous binder was modified with polymer and additive of crumb rubber. First observations of asphalt mixture with the new kind of modified bitumen used on the field section are presented. Rolling resistance of passenger car...

  • Rolling resistance and tyre/road noise on rubberised asphalt pavement in Poland

    The paper presents results of tyre/road noise and rolling resistance measurements performed on stone mastics asphalt (SMA) that contains rubberised asphalt, developed and produced by a refinery in Poland. Bituminous binder was modified with polymer and addition of crumb rubber. The first observations of asphalt mixture with the new kind of modified bitumen used on the field section are presented. Rolling resistance of passenger...

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  • Effects of UV light irradiation on fluctuation enhanced gas sensing by carbon nanotube networks

    Publication

    - SENSORS AND ACTUATORS B-CHEMICAL - Year 2022

    The exceptionally large active surface-to-volume ratio of carbon nanotubes makes it an appealing candidate for gas sensing applications. Here, we studied the DC and low-frequency noise characteristics of a randomly oriented network of carbon nanotubes under NO2 gas atmosphere at two different wavelengths of the UV light-emitting diodes. The UV irradiation allowed to sense lower concentrations of NO2 (at least 1 ppm) compared to...

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  • PERS - QUIET ROAD SURFACE FOR URBAN AREAS

    Publication

    Traffic noise is one of the most important environmental problems in densely populated urban areas. At low speeds the tyre/road interaction dominates all other sources. It is anticipated that when electric and hybrid vehicles gain dominance in city traffic, the importance of tyre/road noise will still increase as electric engines are much less noisy than combustion engines. On the other hand, electric and hybrid urban vehicles...

  • Noise and Electro-Ultrasonic Spectroscopy of Conducting PolymerThick Films

    Publication

    - Year 2011

    Thick conducting films based on conducting polymer are characterized by DC conductivity and noise in temperature range 10 to 300 K. Conducting polymers could be used e.g. for the top electrode (cathode) in the solid tantalum or niobium capacitors. On the conducting polymer layer the top layer of carbon/graphite and/or silver polymer based pastes is applied in the capacitor technology. Our samples structure consists of conducting...

  • EMI mitigation of GaN power inverter leg by local shielding techniques

    Publication

    - IEEE TRANSACTIONS ON POWER ELECTRONICS - Year 2022

    This paper presents local shielding techniques applied to a half-bridge inverter leg with the aim to reduce the common mode (CM) current noise at converter’s DC input. The research study is conducted for 650V Enhancement mode Gallium Nitride (GaN) power transistor switches. Main contributors of parasitic capacitances referred to the inverter-leg middle point node are identified. Then, shielding solutions are proposed to reduce...

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  • The reduction of vibrations in circular sawing machines

    Publication

    The presented in this paper the main objectives of the research were to explore vibrations signals of the main spindle system, the machine tool body and a circular saw to extract informative features for assessment of the designs of the panel saw Fx3 and its follower Fx550.Even though the main spindle of the new table sliding saw Fx550 has its rotational speeds larger about 20% in comparison to the Fx3, peak values of the vibrational...

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  • HYDROACOUSTIC NOISE MEASUREMENTS

    Publication

    - Year 2013

    The paper deals mainly with investigation of underwater noise that propagation is in shallow water. In this paper has been presented the experimental investigation results concerning the distribution of the sound field pressure generated by moving ships in the shallow water at the small distance from the ship. The main acoustical characteristics describing features of the field are spectrograms in pseudo 3D system – distance and frequency...

  • Split-beam echosounder data from Gdansk Deep Summer 2019

    Open Research Data
    open access

    The acoustic data was collected in 2019, in the Gdansk Deep, in the season: Summer. Data was collected during the day and night. Three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz were used to collect the data. The data was collected while the ship was sailing. To ensure data quality, echosounders were calibrated and passive...

  • Localization of impulsive disturbances in audio signals using template matching

    In this paper, a new solution to the problem of elimination of impulsive disturbances from audio signals, based on the matched filtering technique, is proposed. The new approach stems from the observation that a large proportion of noise pulses corrupting audio recordings have highly repetitive shapes that match several typical “patterns”. In many cases a representative set of exemplary pulse waveforms can be extracted from the...

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  • Estimation and Prediction of Vertical Deformations of Random Surfaces, Applying the Total Least Squares Collocation Method

    Publication

    - SENSORS - Year 2020

    This paper proposes a method for determining the vertical deformations treated as random fields. It is assumed that the monitored surfaces are subject not only to deterministic deformations, but also to random fluctuations. Furthermore, the existence of random noise coming from surface’s vibrations is also assumed. Such noise disturbs the deformation’s functional models. Surface monitoring with the use of the geodetic levelling...

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  • Automatic sound source localization in disturbing conditions using acoustic vector sensors

    A concept, practical realization and applications of a passive acoustic radar to automatic localization and tracking of sound sources in disturbing conditions were presented in the paper. The device consists of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. The sensitivity of the realized acoustic radar was examined in free sound field. Several kinds of sound...

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  • Symulacja hałasu emitowanego przez przejeżdżający pojazd

    Przedstawiono program komputerowy Vehicle Noise Simulation umożliwiający przeprowadzenie symulacji hałasu przejeżdżającego pojazdu w oparciu o charakterystyki kierunkowe dźwięku emitowanego przez poszczególne źródła hałasu w pojeździe takie jak: opony, silnik, układ wydechowy.

  • AUTOMATED SYSTEM FOR FLUCTUATION ENHANCED GAS SENSING

    Resistance gas sensors exhibit random phenomena (resistance noise) which can be utilized to improve gas sensitivity and selectivity. That new emerging technique has to be investigated to recognize optimal parameters for gas detection. It means that a measurement system has to have ability of numerous parameters adjustment (e.g., sampling frequency, heater voltage, polarization current, voltage noise amplification). That fact induced...

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  • Progress towards a unified approach to entanglement distribution

    Publication

    - PHYSICAL REVIEW A - Year 2015

    Entanglement distribution is key to the success of secure communication schemes based on quantum mechanics, and there is a strong need for an ultimate architecture able to overcome the limitations of recent proposals such as those based on entanglement percolation or quantum repeaters. In this work we provide a broad theoretical background for the development of such technologies. In particular, we investigate the question of whether...

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  • Ultra-Wideband Vivaldi Antenna with an Integrated Noise-Rejecting Parasitic Notch Filter for Online Partial Discharge Detection

    Publication
    • S. M. Kameli
    • S. S. Refaat
    • H. Abu-Rub
    • A. Darwish
    • A. Ghrayeb
    • M. Olesz

    - IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT - Year 2024

    Power transformers and gas-insulated switchgear (GIS) play crucial roles in electrical power grids. However, they may suffer from degradation of insulation material due to wear and tear, leading to their imminent failure. Partial discharges (PDs) are an initial sign of insulation materials degradation which emit signals spanning various physical domains, including electromagnetic. PDs are temporally narrow, high-frequency, stochastic...

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  • Split-beam echosounder data from Puck Bay autumn 2018

    Open Research Data
    open access

    The acoustic data was collected in 2018, in the Bay of Puck, in the seasons: autumn. Data was collected during the day and night. Three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz were used to collect the data. The data was collected at a designated study area not far from the city of Hel, while the ship was sailing. To ensure...

  • Split-beam echosounder data from Puck Bay spring 2019

    Open Research Data
    open access

    The acoustic data was collected in 2019, in the Bay of Puck, in the season: spring. Data was collected during the day and night. Three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz were used to collect the data. The data was collected at a designated study area not far from the city of Hel, while the ship was sailing. To ensure...

  • Split-beam echosounder data from Puck Bay spring 2019 Part II

    Open Research Data
    version 1.0 open access

    The acoustic data was collected in 2019, in the Bay of Puck, in the season: spring. Data was collected during the sunrise and sunset. Three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz were used to collect the data. The data was collected at a designated study area not far from the city of Hel, while the ship was sailing....

  • Electrical and noise responses of graphene/AlGaN/GaN field-effect transistor for nitrogen dioxide, teatrahydrofuran, and acetone sensing

    Open Research Data
    open access

    This data set consists of raw and modified data concerning current-voltage characteristics and low-frequency noise spectra measured for graphene/AlGaN/GaN field-effect transistor in the ambiance of selected gases (laboratory air, dry and wet synthetic air, nitrogen dioxide, tetrahydrofuran, and acetone). The data show that sensor responses are enhanced...

  • Impact of the glazed roof on acoustics of historic interiors

    Publication

    - Year 2018

    The paper discusses the adverse acoustic phenomena occurring in the semi-open interiors (courtyards, yards) covered with a glass roof. Particularly negative is the rever-beration noise, which leads to the degradation of the utility functions of the resulting spaces. It involves the drastically reducing the intelligibility of speech, loss of natural sounding of music, problems with the sound system, as well as disturbances in the...

  • Method of selecting the LS-SVM algorithm parameters in gas detection process

    In this paper we showed the method of resistive gas sensors data processing. The UV irradiation and temperature modulation was applied to improve gas sensors’ selectivity and sensitivity. Noise voltage across the sensor’s terminals (proportional to its resistance fluctuations) was recorded to estimate power spectral density. This function was an input data vector for LS-SVM (least squares – support vector machine) algorithm, which...

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  • Realistic noise-tolerant randomness amplification using finite number of devices

    Publication
    • F. Brandão
    • R. Ramanathan
    • A. Grudka
    • K. Horodecki
    • M. Horodecki
    • P. Horodecki
    • T. Szarek
    • H. Wojewódka

    - Nature Communications - Year 2016

    Randomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification...

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  • DEVELOPMENT OF A COUPLED NUMERICAL AND EXPERIMENTAL APPROACH TO HYDRODYNAMIC NOISE ESTIMATION

    The hydroacoustic signature of ships' propellers can be estimated experimentally through measurements of cavitation-induced pressure fluctuations and the corresponding noise distributions at model scale. These measurements need to be performed in a cavitation tunnel under the propellers operating conditions and are quite sensitive and challenging to perform with sufficient accuracy. In comparison, the numerical approach can be...

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  • Angle Tracking Observer for Filtering Rotor Position Estimates in Sensorless Electric Drives

    Sensorless electric drives use measurements of electrical quantities to estimate rotor position and speed. Measurement errors deteriorate the estimation accuracy, thus additional means are necessary to remove high-frequency components from estimated signals. This paper proposes to use an Angle Tracking Observer (ATO) for reducing noise in rotor position estimates, which is related to random errors in the measurements. A simplified,...

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  • Loudness Scaling Test Based on Categorical Perception

    The main goal of this research study is focused on creating a method for loudness scaling based on categorical perception. Its main features, such as: way of testing, calibration procedure for securing reliable results, employing natural test stimuli, etc., are described in the paper and assessed against a procedure that uses 1/2-octave bands of noise (LGOB) for the loudness growth estimation. The Mann-Whitney U-test is employed...

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  • Hardened Steel Surface Waviness Created by Rolling Burnishing Process

    Publication

    The surface of the finishing machined parts is defined mainly by roughness parameters. Growing demands on the part, especially mating sliding or rolling, require the specification of additional parameters, such as waviness parameters, particularly when there is significant resistance to seizing or noise reduction. This paper presents surface waviness characteristics of hardened burnished steel.

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  • Quality assessments of electrochromic devices: the possibleuse of 1/f current noise

    Publication
    • J. Smulko
    • A. Azens
    • L. B. Kish
    • C. G. Granqvist

    - IONICS - Year 2007

    Elementy wykorzystujące zjawisko elektrochromizmu, potrafiące zmieniać przezroczystość za pomocą ładowania/rozładowania ładunkiem elektrycznym, wykonano na bazie laminatów pokrytych porowatą strukturą tlenków Ni oraz tlenków Wi-V. Oba laminaty, na które naniesiono przewodzącą warstwę In2O3, przedzielono warstwą elektrolitu. Obserwowano szumy typu 1/f w prądzie I płynącym w trakcie rozładowywania urządzenia. Gęstość widmowa mocy...

  • Investigating Feature Spaces for Isolated Word Recognition

    Publication
    • P. Treigys
    • G. Korvel
    • G. Tamulevicius
    • J. Bernataviciene
    • B. Kostek

    - Year 2020

    The study addresses the issues related to the appropriateness of a two-dimensional representation of speech signal for speech recognition tasks based on deep learning techniques. The approach combines Convolutional Neural Networks (CNNs) and time-frequency signal representation converted to the investigated feature spaces. In particular, waveforms and fractal dimension features of the signal were chosen for the time domain, and...

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  • Absorption spectroscopy setup for determination of whole human blood and blood–derived materials spectral characteristics

    Publication

    A dedicated absorption spectroscopy system was set up using tungsten-halogen broadband source, optical fibers, sample holder, and a commercial spectrometer with CCD array. Analysis of noise present in the setup was carried out. Data processing was applied to the absorption spectra to reduce spectral noise, and improve the quality of the spectra and to remove the baseline level. The absorption spectra were measured for whole blood...

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  • MATCHED FILTER APPROACH FOR MICROSEISMIC SIGNAL PROCESSING OF REAL DATA FROM EAST POMERANIA SHALE GAS

    The microseismic monitoring is a method of monitoring of fracture propagation during hydraulic fracturing (HF)process. An array of several hundred geophones is placed on the surface to record little ground tremors induced by fracturing process. Filtration and summation of signals from geophones is essential to identify and locate fracturing events from underground. Authors propose a method of matched filtering, that is usually...

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  • Analysis of an Attenuator Artifact in an Experimental Attack by Gunn–Allison–Abbott Against the Kirchhoff-Law–Johnson-Noise (KLJN) Secure Key Exchange System

    Publication

    - FLUCTUATION AND NOISE LETTERS - Year 2015

    A recent paper by Gunn–Allison–Abbott (GAA) [L. J. Gunn et al., Scientific Reports 4 (2014) 6461] argued that the Kirchhoff-law–Johnson-noise (KLJN) secure key exchange system could experience a severe information leak. Here we refute their results and demonstrate that GAA’s arguments ensue from a serious design flaw in their system. Specifically, an attenuator broke the single Kirchhoff-loop into two coupled loops, which is an...

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  • Some aspects of noise generated by a small ship in the shallow sea

    Publication

    - Year 2012

    The passing and underwater moving objects produce the noises of variable intensity, which significantly increase the overall level of noise in the sea. This applies to both the sonic and ultrasonic range. The excessive levels of underwater noise adversely affects the so-called underwater acoustic climate and is the reason why this phenomenon is intensively investigated from the number of years. The results of experimental work...

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  • Split-beam echosounder data from Puck Bay winter 2019

    Open Research Data
    open access

    The acoustic data was collected in 2019, in the Bay of Puck, in the season: winter. Data was collected during the day and night. Three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz were used to collect the data. The data was collected at a designated study area not far from the city of Hel, on the route Hel - Gdynia and on...

  • Selected acoustic images of the Gdansk Bay

    Publication

    The main goal of the paper is to describe the results of sounding the Gdansk Bay seabed by using a parametric sub-bottom profiler, multibeam echosounder and side scan sonar. Quality of dsata obtained during trials depends interalia on a proper location of antenna to reduce influence of pitch, roll and heave motions as well as ship noise.

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  • Towards Robust Identification of Nonstationary Systems

    Publication

    The article proposes a fast, two-stage method for the identification of nonstationary systems. The method uses iterative reweighting to robustify the identification process against the outliers in the measurement noise and against the numerical errors that may occur at the first stage of identification. We also propose an adaptive algorithm to optimize the values of the hyperparameters that are crucial for this new method.

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  • Image Segmentation of MRI image for Brain Tumor Detection

    Publication

    - Year 2020

    this research work presents a new technique for brain tumor detection by the combination of Watershed algorithm with Fuzzy K-means and Fuzzy C-means (KIFCM) clustering. The MATLAB based proposed simulation model is used to improve the computational simplicity, noise sensitivities, and accuracy rate of segmentation, detection and extraction from MR...

  • INVESTIGATION OF THE LOMBARD EFFECT BASED ON A MACHINE LEARNING APPROACH

    Publication

    The Lombard effect is an involuntary increase in the speaker’s pitch, intensity, and duration in the presence of noise. It makes it possible to communicate in noisy environments more effectively. This study aims to investigate an efficient method for detecting the Lombard effect in uttered speech. The influence of interfering noise, room type, and the gender of the person on the detection process is examined. First, acoustic parameters...

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  • An Attempt to Create Speech Synthesis Model That Retains Lombard Effect Characteristics

    Publication

    - Year 2019

    The speech with the Lombard effect has been extensively studied in the context of speech recognition or speech enhancement. However, few studies have investigated the Lombard effect in the context of speech synthesis. The aim of this paper is to create a mathematical model that allows for retaining the Lombard effect. These models could be used as a basis of a formant speech synthesizer. The proposed models are based on dividing...

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  • Detection and Mitigation of GPS Spoofing Based on Antenna Array Processing

    In this article authors present an application of spatial processing methods for GPS spoofing detection and mitigation. In the first part of this article, a spoofing detection method, based on phase delay measurements, is proposed. Accuracy and precision of phase delay estimation is assessed for various qualities of received signal. Spoofing detection thresholds are determined. Efficiency of this method is evaluated in terms of...

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  • Raman Spectra Measurements for Chemical Identifications - Aspect of Uncertainty Sources and Reduction of Their Effects

    Raman spectrometers enable fast and non-contact identification of examined chemicals. These devices measure Raman spectra and compare with the spectra database to identify unknown and often illicit chemicals (e.g. drugs, explosives) usually without any sample preparation. Raman spectra measurements are a challenge due to noise and interferences present outside the laboratories (field applications). The design of a portable Raman...

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  • Study on the applicability of the measurements of magnetoelastic properties for a nondestructive evaluation of thermally inducted microstructure changes in the P91 grade steel

    The paper presents the resuIts of the investigation of the influence of duration and temperature oftempering process on the magnetoacoustic properties of P91 tempered martensite ferritic steeI. Duringtempering of martensitic steels the dislocation density. which initially is very high. systematicallydecreases what is confirmed both by analysis of the width of X-ray diffraction peaks and hardnessmeasurements. Magnetic hysteresis...

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  • Wave Method for Structural Health Monitoring: Testing Using Full-Scale Shake Table Experiment Data

    Publication

    - JOURNAL OF STRUCTURAL ENGINEERING-ASCE - Year 2017

    An algorithm of the wave method for structural health monitoring (SHM) is tested and calibrated using shake table experiment data of a full-scale, seven-story, reinforced-concrete building slice. The method is based on monitoring changes in the velocity of waves propagating vertically through the structure, identified by least-squares (LSQ) fit of beam models. The experiment was conducted by a team from the University of California,...

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  • Regularized Identification of Time-Varying FIR Systems Based on Generalized Cross-Validation

    Publication

    A new regularization method is proposed and applied to identification of time-varying finite impulse response systems. We show, that by a careful design of the regularization constraint, one can improve estimation results, especially in the presence of strong measurement noise. We also show that the the most appropriate regularization gain can be found by direct optimization of the generalized cross-validation criterion.

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  • Separability Assessment of Selected Types of Vehicle-Associated Noise

    Music Information Retrieval (MIR) area as well as development of speech and environmental information recognition techniques brought various tools in-tended for recognizing low-level features of acoustic signals based on a set of calculated parameters. In this study, the MIRtoolbox MATLAB tool, designed for music parameter extraction, is used to obtain a vector of parameters to check whether they are suitable for separation of...

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  • Online Sound Restoration for Digital Library Applications

    Publication

    A system for sound restoration was conceived and engineered having the following features: no special sound restoration software is needed to perform audio restoration by the user, the process of restoration employs automatic reduction of noise, wow and impulse distortions performed in the online mode, no skills in digital signal processing from the user are needed. The principles of the created system and its features as well...

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  • Split-beam echosounder data from Puck Bay autumn 2018 Part II

    Open Research Data
    open access

    The acoustic data was collected in 2018, in the Bay of Puck, in the seasons: autumn. Data was collected during the day and night. Three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz were used to collect the data. The data was collected at a designated study area not far from the city of Hel and on the route Hel - Gdynia while...

  • Low frequency nois of supecapacitor

    Open Research Data
    open access

    Dataset contains noise measurement results on prototype electrochemical double layer capacitor. The measurement procedure is described in https://dx.doi.org/10.1515/mms-2017-0059.

  • An adaptive-noise Augmented Kalman Filter approach for input-state estimation in structural dynamics

    Publication
    • S. Vettori
    • E. Di Lorenzo
    • B. Peeters
    • M. Łuczak
    • E. Chatzi

    - MECHANICAL SYSTEMS AND SIGNAL PROCESSING - Year 2023

    The establishment of a Digital Twin of an operating engineered system can increase the potency of Structural Health Monitoring (SHM) tools, which are then bestowed with enhanced predictive capabilities. This is particularly relevant for wind energy infrastructures, where the definition of remaining useful life is a main driver for assessing the efficacy of these systems. In order to ensure a proper representation of the physical...

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  • Split-Beam Echosounder Data from Puck Bay

    Publication

    - Year 2022

    The acoustic data was collected in 2018–2019 in the Bay of Puck in the seasons: autumn, winter, spring. The data was collected during the day and night using three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz at a designated study area not far from the city of Hel, while the ship was sailing. To ensure data quality, the echosounders were calibrated and passive noise was measured.

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  • Tinnitus Therapy Based on High-Frequency Linearization

    Publication

    - Year 2011

    The aim of this work was to present problems related to tinnitus symptoms, its pathogenesis, hypotheses on tinnitus causes, and therapy treatments to reduce or mask the phantom noise. In addition, the hypothesis on the existence of parasitic quantization that accompanies hearing loss was recalled. The paper contains a description of experiments carried out with the application of high-frequency dither having specially formed spectral...

  • Cheap Cancellation of Strong Echoes for Digital Passive and Noise Radars

    The problem of cancellation of strong, potentially nonstationary,echoes in noise radars and passive radars utilizing digitaltransmissions is considered. The proposed solution is a multi-stage procedure.Initial clutter estimates, obtained using the least mean squares(LMS) algorithm, are refined using specially designed filters, "matched"to spectral densities of targets and clutter. When the postprocessing filtersare noncausal, the...

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  • Electrical and noise responses of Graphene-Silicon Schottky diodes decorated with Au nanoparticles for light-enhanced sensing of organic gases

    Open Research Data
    open access

    Graphene-Silicon Schottky junctions decorated with Au nanoparticles were used for light-enhanced detection of organic tetrahydrofuran and chloroform. Au nanoparticles exhibited localized surface plasmon resonance (LSPR) in the range of yellow light; thus yellow LED (wavelength of 592 nm) was utilized to induce the plasmonic effect, that increased the...

  • Semantic segmentation training using imperfect annotations and loss masking

    One of the most significant factors affecting supervised neural network training is the precision of the annotations. Also, in a case of expert group, the problem of inconsistent data annotations is an integral part of real-world supervised learning processes, well-known to researchers. One practical example is a weak ground truth delineation for medical image segmentation. In this paper, we have developed a new method of accurate...

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  • Deep-Learning-Based Precise Characterization of Microwave Transistors Using Fully-Automated Regression Surrogates

    Publication

    - Scientific Reports - Year 2023

    Accurate models of scattering and noise parameters of transistors are instrumental in facilitating design procedures of microwave devices such as low-noise amplifiers. Yet, data-driven modeling of transistors is a challenging endeavor due to complex relationships between transistor characteristics and its designable parameters, biasing conditions, and frequency. Artificial neural network (ANN)-based methods, including deep learning...

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  • The Use of Wavelet Analysis to Denoising of Electrocardiography Signal

    Publication

    The electrocardiography examination, due to its accessibility and simplicity, has an important role in diagnostics of the heart ailments. It enables quick detection of various heart defects, undetectable by other kinds of diagnostic tools, so it is very popular. Nevertheless, the measured signal is exposed to a different disturbances. Among them, the electromagnetic interferences, drift of reference electrode and high frequency...

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  • Online sound restoration system for digital library applications

    Audio signal processing algorithms were introduced to the new online non-commercial service for audio restoration intended to enhance the content of digitized audio repositories. Missing or distorted audio samples are predicted using neural networks and a specific implementation of the Jannsen interpolation method based on the autoregressive model (AR) combined with the iterative restoring of missing signal samples. Since the distortion...

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  • Comparison of noise reduction methods in radiometric correlation measurements of two-phase liquid-gas flows

    Publication

    - MEASUREMENT - Year 2018

    Two-phase liquid-gas flows occur frequently in the mining, energy, chemical, and petrochemical industries. One of non-contact methods used to analyse these flows is the gamma ray absorption method. However, the signals received from radiation detectors contain a significant stochastic noise, which makes them difficult to analyse. The article describes four methods of noise reduction in cross-correlation measurements of water-air...

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  • Spectral Analysis of Capital Markets

    In this paper the problem of cycles existence in capital markets is addressed. A spectral analysis algorithm, which reduces signal-to-noise ratio, is proposed to derive cycle periodograms for the yield function of DJIA, WIG~20, and NIKKEI 225 indices. Peaks of the the periodograms provide premises to postulate the existence of some possible cycles. The 3.5 year periodicity in all 3 indices, which can be related to Kitchin cycle...

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  • Blood Pressure - Pulse Transit Time Relationships: Comparative Studies

    Publication

    A non-invasive and continuous blood pressure estimation could allow a better diagnosis and an earlier detection of various diseases. It could be performed using a photoplethysmography. However, it requires that a relation between blood pressure and pulse transit time is known. Eleven theoretical formulas were used in obtaining the simulated and noise free synthetic data. Then, they were utilized in validation of three, commonly...

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  • Multifrequency self-optimizing narrowband interference canceller

    Publication

    The problem of cancellation of a nonstationary sinusoidal interference, acting at the output of a linear stable plant, is considered. It is assumed that disturbance is a multifrequency narrowband signal, and that system output is contaminated with wideband noise. It is not assumed that the reference signal is available. Two disturbance cancelling schemes are proposed, one for disturbances with unrelated frequency components, and...

  • Experimental generation of complex noisy photonic entanglement

    Publication
    • K. Dobek
    • M. Karpiński
    • R. Demkowicz-Dobrzański
    • K. Banaszek
    • P. Horodecki

    - LASER PHYSICS - Year 2013

    We present an experimental scheme based on spontaneous parametric down-conversion to produce multiple-photon pairs in maximally entangled polarization states using an arrangement of two type-I nonlinear crystals. By introducing correlated polarization noise in the paths of the generated photons we prepare mixed-entangled states whose properties illustrate fundamental results obtained recently in quantum information theory, in particular those...

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  • New Approach to Noncasual Identification of Nonstationary Stochastic FIR Systems Subject to Both Smooth and Abrupt Parameter Changes

    In this technical note, we consider the problem of finite-interval parameter smoothing for a class of nonstationary linear stochastic systems subject to both smooth and abrupt parameter changes. The proposed parallel estimation scheme combines the estimates yielded by several exponentially weighted basis function algorithms. The resulting smoother automatically adjusts its smoothing bandwidth to the type and rate of nonstationarity...

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  • A Framework for Searching in Graphs in the Presence of Errors

    Publication

    - Year 2019

    We consider a problem of searching for an unknown target vertex t in a (possibly edge-weighted) graph. Each vertex-query points to a vertex v and the response either admits that v is the target or provides any neighbor s of v that lies on a shortest path from v to t. This model has been introduced for trees by Onak and Parys [FOCS 2006] and for general graphs by Emamjomeh-Zadeh et al. [STOC 2016]. In the latter, the authors provide...

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  • Active Control of Highly Autocorrelated Machinery Noise in Multivariate Nonminimum Phase Systems

    In this paper, a novel multivariate active noise control scheme, designed to attenuate disturbances with high autocorrelation characteristics and preserve background signals, is proposed. The algorithm belongs to the class of feedback controllers and, unlike the popular feedforward FX-LMS approach, does not require availability of a reference signal. The proposed approach draws its inspiration from the iterative learning control...

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  • Assessment of particular abdominal aorta section extraction from contrast-enhanced computed tomography angiography

    Publication

    The aim of this work is to improve the accuracy of extraction of a particular abdominal aorta section and to reduce the distortion in three-dimensional Computed Tomography Angiography (CTA) images. Imaging modality and quality plays crucial role in the medical diagnostic process, thus ensuring high quality of images is essential at every stage of acquisition and processing.Noise is defined as a disturbance of the image quality...

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  • Analysis of the Dynamic Height Distribution at the Estuary of the Odra River Based on Gravimetric Measurements Acquired with the Use of a Light Survey Boat—A Case Study

    Publication

    - SENSORS - Year 2020

    LaCoste) for determining the dynamic height along the Odra River, in northwest Poland. The gravity measurement campaign described in this article was conducted on a small, hybrid-powered survey vessel (overall length: 9.5 m). We discuss a method for processing the results of gravimetric measurements performed on a mobile platform affected by strong external disturbances. Because measurement noise in most cases consists of signals...

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  • Tyre/road noise measurements on ISO tracks according to the UNECE Regulation 117

    Publication

    - Year 2022

    Within the Polish-Norwegian research project ELANORE, a limited Round Robin Test has been performed on 3 ISO tracks in Northern Europe. The basic objective of the project is to improve the EU directive on labelling of tyres for noise and rolling resistance, and this directive is based on the measurement procedures defined in the UN ECE Reg.117. The same test car, test tyres and measurement equipment as well as personnel were used...

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  • Medley filters - simple tools for efficient signal smoothing

    Publication

    - Year 2010

    Medley filters are defined as convex combinations of elementary smoothing filters (averaging, median) with different smoothing bandwidths. It is shown that when adaptive weights of such a mixture are evaluated using the recently proposed Bayesian rules, one obtains a tool which often outperforms the state-of-the-art wavelet-based smoothing algorithms. Additionally, unlike wavelet-based procedures, medley filters can easily cope...

  • Computer-aided analysis of signals from a low-coherence Fabry-Perot interferometer used for measurements of biological samples

    Publication

    The aim of the study was to develop an automated computer-aided system for analysis of spectrograms obtained from measurements of biological samples performed with a low-coherence Fabry-Pérot interferometer. Information necessary to determine dispersion characteristics of measured materials can be calculated from the positions of the maxima and minima that are present in their spectra. The main challenge faced during the development...

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