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Wyniki wyszukiwania dla: 1/F NOISE

  • Silence/noise detection for speech and music signals

    Publikacja

    - Rok 2008

    This paper introduces a novel off-line algorithm for silence/noise detection in noisy signals. The main concept of the proposed algorithm is to provide noise patterns for further signals processing i.e. noise reduction for speech enhancement. The algorithm is based on frequency domain characteristics of signals. The examples of different types of noisy signals are presented.

  • Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method

    Publikacja

    - APPLIED ACOUSTICS - Rok 2016

    Performing numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...

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  • INFLUENCE OF MEASURING CONDITIONS ON TYRE/ROAD NOISE

    Publikacja

    - Rok 2016

    A decisive factor for the development of tyres and road surfaces is the ability to conduct representative and reproducible measurements of selected characteristics related to the interaction of tyres and road surfaces. In terms of tyre/road noise measurements in Europe two methods described in ISO/FDIS 11819-2 and ECE Regulation No.117 are used. The latter is compulsory for assigning the tyre noise labels. The methodologies differ...

  • Ultra Low Noise Poroelastic Road Surfaces

    Publikacja

    Noise is one of the most important environmental problems related to road traffic. During the last decades, the noise emitted by the engines and powertrains of vehicles was greatly reduced and tires became a clearly dominant noise source. The article describes the concept of low noise poroelastic road surfaces that are composed of mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and...

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  • Multimedia services applied to noise and hearing monitoring and measuring

    Publikacja

    The goal of this chapter is to show a research study related to processing of data acquired by the multimedia services engineered at the multimedia systems department (MSD) of the Gdansk University of Technology. This concerns a survey on noise threat employing the multimedia noise monitoring system (MNMS) and hearing tests performed by the "I can hear. . . " system. The obtained results of the noise measurements revealed that...

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  • AC Motor Voltage and Audible Noise Dataset

    Publikacja

    - Rok 2022

    The dataset titled AC motor voltage and audible noise waveforms in ship’s electrical drive systems with frequency converters contains the voltage and sound measurement results recorded in a marine frequency controlled AC drive system. The dataset is part of research focussing on the impact of the ship’s electrical drive systems with frequency converters on vibrations and the level of audible noise on ships. The dataset allows the...

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  • Investigation of Noise Threats and Their Impact on Hearing in Selected Schools

    Publikacja

    - Rok 2006

    Noise measurements conducted in selected schools in Gdansk area are presented in this paper. The main aim of this research was to determine noise threats at schools. Some objective measurements of the acoustic climate were performed employing a noise monitoring station engineered at the Multimedia System Department, Gdansk University of Technology. Simultaneously, subjective noise annoyance examinations were carried out among pupils...

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  • A new nethod for RTS noise of semiconductor devices identification

    In the paper, a new method, called the noise scatterin pattern method (NSP method), for random telegraph signal noise identyfication in the inherent noise of semiconductor devices is described. A block diagram of a noise measurement system based on the NSP method is presented. Examples of patterns of the NSP method are presented.

  • Noise and Electro-Ultrasonic Spectroscopy of Conducting PolymerThick Films

    Publikacja

    - Rok 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...

  • ROSANNE Project: New Procedure for Noise Characterisation of Road Surfaces in Europe

    Publikacja
    • M. Conter
    • R. Wehr
    • C. Aichinger
    • U. Sandberg
    • P. Mioduszewski
    • L. Goubert
    • P. Morgan
    • H. S. Rosmus
    • F. Ledee

    - Rok 2016

    ROSANNE is a collaborative project in the 7th EU Framework Programme which aims at harmonising measurement methods for skid resistance, noise emission and rolling resistance of road pavements as a preparation for standardization. The project started in November 2013 and is developing and improving standards in the field of working group CEN/TC 227/WG 5. Regarding the influence of the pavement on the road traffic noise emission,...

  • Noise related to gas bottles explosions

    Modern industrialized world is in a never ending danger of accidents and catastrophes of technical nature. Some of them may involve fires and explosions of gas storage bottles or containers. Technical University of Gdansk, Poland performed numerous tests where bottles containing acetylene, oxygen, hydrogen, CO2, LPG, LNG or CNG were blown due to excessive temperature caused by fire. Although those experiments were not focused on...

  • Applying the Lombard Effect to Speech-in-Noise Communication

    Publikacja

    - Electronics - Rok 2023

    This study explored how the Lombard effect, a natural or artificial increase in speech loudness in noisy environments, can improve speech-in-noise communication. This study consisted of several experiments that measured the impact of different types of noise on synthesizing the Lombard effect. The main steps were as follows: first, a dataset of speech samples with and without the Lombard effect was collected in a controlled setting;...

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  • Risk assessment of biocides in roof paint. Part 1

    Publikacja

    - ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH - Rok 2008

    Szereg pokryć dachowych, jak farby dachowe, zawiera w swoim składzie biocydy. Dotychczas nie wiadomo do jakiego stopnia biocydy wymywane są z farb dachowych, a ponadto jakie ich stężenie może występować w systemach zbierających wodę deszczową. Zbadano podatność na wymywanie biocydów z różnych niemieckich farb dachowych oraz oszacowano ich stężenie w zebranej wodzie deszczowej

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  • Semi-adaptive feedback active control of MRI noise

    Publikacja

    - Rok 2011

    A feedback controller is proposed for cancellation of magnetic resonance imaging (MRI) noise. The design of the controller takes into account specific features of the MRI noise signal. Simulation results show that a considerable rejection rate of the MRI noise can be obtained.

  • DNA modification by 1-nitroacridine derivatives. Comparison of 32P-Postlabeling and restriction enzyme analysis method for the detection of DNA adducts formed by 1-nitroacridines C-1748 and C-857

    Publikacja

    - Rok 2006

    4-podstawione 1-nitroakrydyny reprezentują nową grupę pochodnych akrydyny, zsyntetyzowanych na Politechnice Gdańskiej. Metoda 32P-postlabellingu wykazała, że pochodne C-1748 i C-857 tworzą od 4-6 adduktów DNA w systemie komórkowym i bezkomórkowym o innym rozkładzie plam chromatograficznych, jednakże niezależnym od zastosowanego systemu aktywacyjnego. Metoda enzymatycznej analizy restrykcyjnej pozwoliła natomiast śledzić kinetykę...

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  • Improvement of speech intelligibility in the presence of noise interference using the Lombard effect and an automatic noise interference profiling based on deep learning

    Publikacja
    • K. Kąkol

    - Rok 2023

    The Lombard effect is a phenomenon that results in speech intelligibility improvement when applied to noise. There are many distinctive features of Lombard speech that were recalled in this dissertation. This work proposes the creation of a system capable of improving speech quality and intelligibility in real-time measured by objective metrics and subjective tests. This system consists of three main components: speech type detection,...

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  • Photophysics of Ru(II) Dyads Derived from Pyrenyl-Substitued Imidazo[4,5-f][1,10]phenanthroline Ligands.

    Publikacja
    • C. Reichardt
    • M. Pinto
    • M. Wachtler
    • M. Stephenson
    • S. Kupfer
    • T. Sainuddin
    • J. Guthmuller
    • S. A. Mcfarland
    • B. Dietzek

    - JOURNAL OF PHYSICAL CHEMISTRY A - Rok 2015

    The photophysics of a series of Ru(II) dyads based on the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline ligand was investigated. The ability of these metal complexes to intercalate DNA and induce cell death upon photoactivation makes them attractive photosensitizers for a range of photobiological applications, including photodynamic therapy. In the present study, time-resolved transient absorption and emission spectroscopy...

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  • Tripping of F-type RCDs for sinusoidal residual current with superimposed smooth DC component

    Publikacja

    - Rok 2022

    Recent trends in green energy development make that photovoltaics and electric vehicles are applied on an increasing scale. In both photovoltaic and electric vehicle charging installations, a significant value of DC component of the earth fault current may appear, which is a challenge, in particular, for commonly used residual current devices (RCDs). This paper presents results of the laboratory test on the operation of F-type...

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  • Methods of electrochemical noise analysis for investigation of corrosion processes

    Publikacja

    Korozja elektrochemiczna może być oceniana za pomocą przpływu ładunków między korodującym metalem a elektrolitem. Zwykle, przpływ ładunku obserwuje się w układzie trzech elektrod jako fluktuacje prądu i napięcia (szumy elektrochemiczne). Na podstawie analizy szumów elektrochemicznych można wykrywać różne rodzaje korozji. Korozja jednorodna jest oceniana za pomocą wartości rezystancji polaryzacyjnej występującej między metalem a...

  • APPLICATION OF NON-STATIONARY TECHNIQUES IN THE ANALYSIS OF ELECTROCHEMICAL NOISE

    Publikacja

    - FLUCTUATION AND NOISE LETTERS - Rok 2004

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  • Biological hazards in low noise, poroelastic road surfaces

    Publikacja

    - Rok 2013

    Drainage pavements as well as poroelastic pavements ("PERS") are a very efficient way to decrease traffic noise by reducing tire/road noise at the source as well as noise propagation over the road surface. Many noise generating mechanisms at the tire/road interface are very much reduced by road porosity (pipe resonance, "air pumping", Helmholtz resonance and the horn effect). A well-designed porous or poroelastic road surface may...

  • Active feedback noise control in the presence of impulsive disturbances

    Publikacja

    The problem of active feedback control of a narrowband acoustic noise in the presence of impulsive disturbances is considered. It is shown that, when integrated with appropriately designed outlier detector, the proposed earlier feedback control algorithm called SONIC is capable of isolating and rejecting noise pulses. According to our tests this guarantees stable and reliable operation of the closed-loop noise cancelling...

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  • Improving the quality of speech in the conditions of noise and interference

    Publikacja

    The aim of the work is to present a method of intelligent modification of the speech signal with speech features expressed in noise, based on the Lombard effect. The recordings utilized sets of words and sentences as well as disturbing signals, i.e., pink noise and the so-called babble speech. Noise signal, calibrated to various levels at the speaker's ears, was played over two loudspeakers located 2 m away from the speaker. In...

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  • f-Cycles - a new approach to providing fast service recovery at low backup capacity overhead

    Publikacja

    - Rok 2008

    W artykule zaproponowano klasowy algorytm doboru tras przeżywalnych, wykorzystujący autorską koncepcję f-Cykli ochronnych. Celem podejścia było zminimializowanie wartości czasu odtwarzania uszkodzonych strumieni ruchu. Cel ten został osiągnięty poprzez dostosowanie wielkości obszaru ochrony w zależności od klasy usług. Badania symulacyjne pokazały, że wykorzystując autorką koncepcję f-Cykli ochronnych, możliwe jest również jednoczesne...

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  • IMPULSE NOISE ASSOCIATED WITH FIRING HANDHELD MILITARY WEAPONS

    Sports, hunting and military shooting grounds are well known sources of noise that can be disruptive both for people present at those facilities, as well as for people and animals that live nearby. What is more, shooters are also subjected to very painful and dangerous impulse noise. The paper discusses the issues related to the noise immission during firing of small firearms of military type that are typical for Poland. The experiments...

  • UNDERWATER NOISE GENERATED BY A SMALL SHIP IN THE SHALLOW SEA

    Publikacja

    Study of the sea noise has been a subject of interest for years. The first work of this scope were published at the turn of the twentieth century by Knudsen (KNUDSEN et al., 1948) and G. Wenz (WENZ, 1962). Disturbances called "shipping noise" are one of the important components of the sea noise. In this work the results of an experimental research of underwater noise produced by a small ship of a classic propulsion are...

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  • LOW NOISE TIRES FOR HYBRID AND ELECTRIC VEHICLES

    Publikacja

    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...

  • Robust algorithm for active feedback control of narrowband noise

    Publikacja

    The problem of active control of narrowband acoustic noise is considered. It is shown that the proposed earlier feedback control algorithm called SONIC (self-optimizing narrowband interference canceller), based on minimization of the L2-norm performance measure, can be re-derived using the L1 approach. The resulting robust SONIC algorithm is more robust to heavy-tailed measurement noise, such as the αlpha-stable noise, than the...

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  • Methods of trend removal in electrochemical noise data – overview

    Publikacja

    In this paper we shall review popular methods of trend removal from electrochemical noise time records. The basic principles of operation of the six most popular methods are explained. The proposed methods are: high - pass filtering, Moving Average Removal, polynomial detrending, wavelet detrending, Empirical Mode Decomposition and Variational Mode Decomposition. Estimation of trend removal quality...

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  • Partial characterization of white cabbages (Brassica oleracea var. capitata f. alba) from different regions by glucosinolates, bioactive compounds, total antioxidant activities and proteins

    W pracy przedstawiono wyniki oznaczeń glukozynolanów (GLS), aktywności przeciwutleniającej (TRSA) oraz białek w próbkach białej kapusty pochodzącej z różnych rejonów geograficznych Europy. Glukobrassycyna i sinigryna były dominującymi GLS we wszystkich próbkach kapusty. Całkowita zawartość GLS mieściła się w zakresie od 3,3-7,7 µmol/g sm. Aktywność przeciwulteniająca próbek kapusty została oszacowana za pomocą testów ABTS,...

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  • Temperature influence on tyre/road noise of selected tyres

    Publikacja

    Air and road temperatures substantially affect road vehicle noise emission. The temperature influence on tyre/road noise depends mainly on tyre-road combination. It is different for dense and porous pavements, for bituminous and cement ones. It differs also depending on tyres. The correction procedures for temperature effect are still under consideration and preparation. Tyre/road noise measurements using CPX method were performed...

  • Anatomy of noise in quantitative biological Raman spectroscopy

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

    - BIOANALYSIS - Rok 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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  • Sound quality metrics applied to road noise evaluation

    Road noise monitoring systems typically measure sound levels in specific time periods. The more insightful approach suggests to measure also the nature of noise. Sound quality of sounds such as car noise can be objectively evaluated by several parameters. One of them is psychoacoustic annoyance, described by loudness, tone color, and the temporal structure of sound. In this paper the assessment of several sound quality parameters, such...

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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

    Publikacja

    - FLUCTUATION AND NOISE LETTERS - Rok 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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  • Noise profiling for speech enhancement employing machine learning models

    Publikacja

    - Journal of the Acoustical Society of America - Rok 2022

    This paper aims to propose a noise profiling method that can be performed in near real-time based on machine learning (ML). To address challenges related to noise profiling effectively, we start with a critical review of the literature background. Then, we outline the experiment performed consisting of two parts. The first part concerns the noise recognition model built upon several baseline classifiers and noise signal features...

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  • Performance of Noise Map Service Working in Cloud Computing Environment

    In the paper a noise map service designated for the user interested in environmental noise subject is presented. It is based on cloud computing. Noise prediction algorithm and source model, developed for creating acoustic maps, are working in cloud computing environment. In the study issues related to noise modeling of sound propagation in urban spaces are discussed with a special focus on road noise. Examples of results obtained...

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  • Identification of inherent noise components of semiconductor devices on an example of optocouplers

    In the paper, a method of estimation of parameters of Gaussian and non-Gaussian components in the noise signal of semiconductor devices in a frequency domain is proposed. The method is based on composing estimators of two spectra, corresponding to noise (Gaussian component) and two-level RTS noise (non-Gaussian component). The proposed method can be applied for precise evaluation of the corner RTS frequency fRTS in the noise...

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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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  • Waveform design for fast clutter cancellation in noise radars

    Publikacja

    - Rok 2014

    Canceling clutter is an important, but computation-ally intensive part of signal processing in noise radars. It is shown that considerable improvements can be made to a simple least squares canceler if minor constraints are imposed onto noise waveform. The proposed scheme is potentially capable of canceling clutter in real-time, even for high sampling rates.

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  • Noise effect on parameters of quiet sonar with code modulation

    Earlier publications of the paper authors have shown that the use of code keying mixed with the CW FM sound signal allows the significant reduction in the distance measurement error, compared to classic silent CW FM sonar. In addition to the code modulation parameters, the magnitude of this error is influenced by the received input acoustic noise. The article shows the dependence of the input signal-to-noise ratio and the sound...

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  • New approach to railway noise modeling employing Genetic Algorithms

    Publikacja

    Main goal of this paper was to describe an innovative method of noise prediction based on Genetic Algorithms. First part of the paper addresses the problem of growing noise, mainly in the context of a unified method for measuring noise. Further, Genetic Algorithms are described with regards to their fundamental features. Further a description is provided as to how Genetic Algorithms were used in the area of noise modeling. Next...

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  • Effects of mechanical stress on electrical arameters and noise of supercapacitors

    Publikacja

    Results of noise and electrical parameters measurements of prototype electrochemical double layer capacitors (EDLC) are reported at the presence of selected mechanical stress. This issue is of great importance due to future applications in wearable technology. The measurement results are compared, and we may conclude than flicker noise is more sensitive to any stress than other considered electrical parameters.

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  • Tyre/road noise reduction by a poroelastic road surface

    Publikacja

    Low noise road surfaces of existing types may in favourable cases and in new conditions provide up to 7 dB of noise reduction. For higher noise reductions, innovative solutions must be sought. Poroelastic road surfaces (PERS) may be such a solution, which currently is studied in the EU project PERSUADE. This paper presents results of trials with a PERS version prefabricated by one of the project partners. Tests were made in a laboratory...

  • Improving Objective Speech Quality Indicators in Noise Conditions

    Publikacja

    - Rok 2020

    This work aims at modifying speech signal samples and test them with objective speech quality indicators after mixing the original signals with noise or with an interfering signal. Modifications that are applied to the signal are related to the Lombard speech characteristics, i.e., pitch shifting, utterance duration changes, vocal tract scaling, manipulation of formants. A set of words and sentences in Polish, recorded in silence,...

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  • Distributed System For Noise Threat Evaluation Based On Psychoacoustic Measurements

    An innovative system designed for the continuous monitoring of acoustic climate of urban areas was presentedin the paper. The assessment of environmental threats is performed using online data, acquired through a grid ofengineered monitoring stations collecting comprehensive information about the acoustic climate of urban areas.The grid of proposed devices provides valuable data for the purpose of long and short time acoustic climateanalysis....

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  • Robustness of quantum-randomness expansion protocols in the presence of noise

    Publikacja

    - PHYSICAL REVIEW A - Rok 2013

    In this paper we investigate properties of several randomness generation protocols in the device independent framework. Using Bell-type inequalities it is possible to certify that the numbers generated by an untrusted device are indeed random. We present a selection of certificates which guarantee two bits of randomness for each run of the experiment in the noiseless case and require the parties to share a maximally entangled state....

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  • Wybrane problemy naprawy ułożyskowania wału korbowego silnika głównego promu m/f "Wilanów"

    Publikacja

    - TRIBOLOGIA - Rok 2002

    Omówiono problemy i przebieg prac naprawczych ułożyskowania wału korbowego silnika MAN V9V30/45 promu m/f "Wilanów". Istotnym elementem prac było wykorzystanie łożysk technologicznych, co pozwoliło skrócić czas postoju statku o 14 dób.

  • Traffic Noise Analysis Applied to Automatic Vehicle Counting and Classification

    Problems related to determining traffic noise characteristics are discussed in the context of automatic dynamic noise analysis based on noise level measurements and traffic prediction models. The obtained analytical results provide the second goal of the study, namely automatic vehicle counting and classification. Several traffic prediction models are presented and compared to the results of in-situ noise level measurements. Synchronized...

  • Poroelastic Road Surface – a Promising Road Traffic Noise Abatement Solution

    Publikacja

    - Rok 2018

    Road surfaces have a direct impact on the generation of noise by rolling tyres, the main and dominant source of noise of moving vehicles, as well as may affect propagation of noise emitted by all noise sources of a vehicle. Thus there is no doubt that pavement should be considered as one of the major potential road traffic noise abatement measure. Low noise pavements of existing types may in new conditions provide up to 8 dB of...

  • Investigation of noise threats and their impact on hearing in selected schools - a pilot study.

    Publikacja

    Noise measurements conducted in selected schools in Gdansk area are presented in this paper. The main aim of this research was to determine noise threats at schools. Some objective measurements of the acoustic climate were performed employing a noise monitoring station engineered at the Multimedia System Department, Gdansk University of Technology. Simultaneously, subjective noise annoyance examinations were carried out among pupils...

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