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Search results for: TRANSPORTATION NOISE
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Irregular variations in GPS time series by probability and noise analysis
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Two-stage method of impulsive noise detection for audio signals
PublicationPrzedstawiono nowa dwuetapową metodę detekcji zakłóceń impulsowych opartą na analizie funkcji gęstości rozkładu prawdopodobieństwa zakłóconego sygnału. Opisano algorytm określania poziomu wyzwalania detektora progowego.
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Piece-wise constant approximation method of identification of RTS noise
PublicationPrzedstawiono nową metodę wydzielania szumów RTS z całkowitych szumów przyrządów półprzewodnikowych. Metoda ta oparta jest na aproksymacji liniowo odcinkowej przebiegu szumowego.Przedstawiono wyniki zastosowania tej metody do wydzielenia dwupoziomowego szumu RTS z szumu przyrządu półprzewodnikowego.
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Cheap Cancellation of Strong Echoes for Digital Passive and Noise Radars
PublicationThe 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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Some aspects of noise generated by a small ship in the shallow sea
PublicationThe 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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Distributed System For Noise Threat Evaluation Based On Psychoacoustic Measurements
PublicationAn 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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Identification of inherent noise components of semiconductor devices on an example of optocouplers
PublicationIn 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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An improved frequency estimator for an adaptive active noise control scheme
PublicationAn improved frequency tracker is proposed for the recently introduced self optimizing narrowband interference canceller (SONIC). The scheme is designed for disturbances with quasi-linear frequency modulation and, under second-order Gaussian random-walk assumption, can be shown to be statistically efficient. One real-world experiment and several simulations show that a considerable improvement in disturbance rejection may be achieved...
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Dedicated power supply subsystem for ultra-low noise preamplifiers
PublicationIn field of electronics there is need for low-noise amplifiers. Noise have the most important influence on analog circuits. Therefore exist necessity to develop new ultra-low noise power supplies, which can cooperate with specified amplifiers and preamplifiers. It is very common that professional power supplies are very expensive and still have disadvantages. This paper proposes simple and inexpensive solution, which fulfill specific...
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Performance of Noise Map Service Working in Cloud Computing Environment
PublicationIn 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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Traffic Noise Analysis Applied to Automatic Vehicle Counting and Classification
PublicationProblems 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...
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Low Noise Poroelastic Road Pavements Based On Bituminous Binder
PublicationTire/road noise is the dominant source of traffic noise. It depends both on the tire design and on the characteristics of road pavements as well as on the vehicles’ operating conditions. Due to the fact that conventional (pneumatic) car tires have almost reached the limits of their ability to further reduce their noisiness, it is widely believed that the additional reduction of tire noise will be possible mainly through modifications...
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Fast clutter cancellation for noise radars via waveform design
PublicationCanceling clutter is an important, but very expensive 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. Using a combination of FPGA and CPU, the proposed scheme is capable of canceling both stationary clutter and moving targets in real-time, even for high sampling rates.
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New approach to railway noise modeling employing Genetic Algorithms
PublicationMain 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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Shipping Low Frequency Noise and Its Propagation in Shallow Water
PublicationOne of the most significant factor influencing acoustical climate of the sea is underwater noise generated by moving ships. If the considered sea area has features of the shallow water, namely the wave frequency fulfils relation f < 10c/h, where c denotes phase speed of sound, and h is depths of the sea, then in certain distance from the wave source specific image of sound pressure distribution in the mean of wave modes appears....
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Quality assessment of ZnO-based varistors by 1/f noise
PublicationNoise has been used as a diagnostic tool of surge arrester varistor structures comprising of ZnO grains of various type and size. The physical and electrical properties of the measured samples have been described. In the experimental study, the applied measurement system and the results of noise measurements for the selected structures of varistors designed for the continuous working voltage 280 V, 440 V and 660 V have been presented....
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Temperature influence on tire/road noise evaluated by the drum method
PublicationAmbient air and road surface temperatures substantially affect the road vehicle noise emission. The temperature influence on tire/road noise depends mainly on tire-road combination. It is different for dense and porous pavements, for bituminous and cement ones. It differs also depending on tires. The correction procedures for temperature effect are still under consideration and preparation. Laboratory experiment was prepared to...
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Reduction of noise and rolling resistance by horizontal grinding of asphalt pavements
PublicationGrinding 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,...
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Resistance Noise Higher-Order Spectrums in Nanoparticle Gas Sensors.
PublicationPrzedstawiono badania fluktuacji rezystancji sensora gazu wykonanego z nanocząstek WO3. Stwierdzono występowanie składowych o rozkładzie prawdopodobieństwa różnym od rozkładu Gaussa. W celu zwiększenia czułości i selektywności wykrywanych gazów zastosowan do analizy obserwowanych fluktuacji spektra wyższych rzędów.
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Applications of electrochemical noise technique in stress corrosion cracking diagnosis
PublicationW pracy przedstawione zostały rezultaty analizy prądowego szumu elektrochemicznego, generowanego podczas korozji naprężeniowej próbek stali stopowej. W przeciwieństwie do tradycyjnych metod analizy nie zakładano stacjonarności analizowanych sygnałów. Zamiast tego analizie poddana została zmodyfikowana widmowa odpowiedź szumowa o charakterze zależnym od czasu. Rezultaty badań skonfrontowano z wynikami otrzymanymi za pomocą techniki...
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Analysis and Optimization of Noise in Continuous-Time OTA-C Filters
PublicationW pracy przedstawiono ogólną procedurę analizy szumów w filtrach klasy OTA-C czasu ciągłego. Procedura umożliwia analizę filtrów o dowolnej topologii i dowolnego rzędu w ramach rozważanej klasy. W oparciu o opis macierzowy ogólnej struktury filtru OTA-C wyprowadzono ogólne formuły pozwalające na wyznaczanie i optymalizację szumów dowolnego filtru OTA-C. Przedstawione wyniki są użyteczne nie tylko dla klasycznych (dyskretnych lub...
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Noise Analysis and Optimization of Continuous-Time OTA-C Filters
PublicationW pracy przedstawiono efektywną procedurę wyznaczania szumów w filtrach OTA C czasu ciagłego. Procedura wyprowadzona jest w oparciu o ogólny model filtru OTA C oraz jego opis macierzowy. Podano jawne formuły pozwalające okreslić odniesione do wejścia widmo szumów dowolnego filtru rozważanej klasy. Otrzymane wyniki teoretyczne zostały zweryfikowane poprzez porównanie z wynikami otrzymywanymi za pomocą symulatora SPICE dla wybranych...
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Modeling of Electrified Transportation Systems Featuring Multiple Vehicles and Complex Power Supply Layout
PublicationThe paper proposes a novel approach to modeling electrified transportation systems. The proposed solution reflects the mechanical dynamics of vehicles as well as the distribution and losses of electric supply. Moreover, energy conversion losses between the mechanical and electrical subsystems and their bilateral influences are included. Such a complete model makes it possible to replicate, e.g., the impact of voltage drops on vehicle...
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Pipeline system for heat transportation from nuclear power plant — An optimizing approach
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Fatigue tests of steel Sandwich panel. Fifth International Conference on Marine Technology and Transportation.
PublicationW referacie przedstawiono wyniki badań laboratoryjnych paneli SANDWICH prowadzonych w Katedrze Technologii Okrętów, Systemów Jakości i Materiałoznawstwa Wydziału OiO na konstrukcjach w skali rzeczywistej. Dokonano porównania uzyskanych rezultatów w wynikami prezentowanymi w literaturze.
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Assessment of Fuel Cells’ State of Health by Low-Frequency Noise Measurements
PublicationWe proposed applying low-frequency (flicker) noise in proton-exchange membrane fuel cells under selected loads to assess their state of health. The measurement set-up comprised a precise data acquisition board and was able to record the DC voltage and its random component at the output. The set-up estimated the voltage noise power spectral density at frequencies up to a few hundred mHz. We observed the evolution of the electrical...
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Investigating Noise Interference on Speech Towards Applying the Lombard Effect Automatically
PublicationThe aim of this study is two-fold. First, we perform a series of experiments to examine the interference of different noises on speech processing. For that purpose, we concentrate on the Lombard effect, an involuntary tendency to raise speech level in the presence of background noise. Then, we apply this knowledge to detecting speech with the Lombard effect. This is for preparing a dataset for training a machine learning-based...
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A review of design approaches for the implementation of low-frequency noise measurement systems
PublicationElectronic noise has its roots in the fundamental physical interactions between matter and charged particles, carrying information about the phenomena that occur at the microscopic level. Therefore, Low-Frequency Noise Measurements (LFNM) are a well-established technique for the characterization of electron devices and materials and, compared to other techniques, they offer the advantage of being non-destructive and of providing...
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Analysis of the Usefulness of Cheap Audio Recorders for Spectral Measurement of Environmental Noise
PublicationEnvironmental noise pollution is nowadays one of the most serious health threats. The impact of noise on the human body depends not only on the sound level but also on its spectral distribution. Reliable measurements of the environmental noise spectrum are often hampered by the very high price of top quality measuring devices. This paper explores the possibility of using much cheaper audio recorders for the frequency analysis....
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Tire/Road Noise On Poroelastic Road Surfaces - Results Of Laboratory Measurements
PublicationTire/road noise is the most important part of traffic noise for medium and high speed driving both in the case of passenger cars and trucks. The potential to make modification of tires that significantly reduce tire/road noise in nearly over, at least for conventional tires so the only promising action is to improve road pavements. One of the innovative solutions is poroelastic road pavement (PERS) that reduces airflow related...
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On the Handling of Outliers in the GNSS Time Series by Means of the Noise and Probability Analysis
PublicationThe 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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Low noise poroelastic road pavements based on modified asphalt binder
PublicationTire/road noise is one of the most important environmental problems related to road traffic. As the most effective way to fight noise is reduction of sound emission from the source, a lot of work is being done to improve tire and road surfaces construction. This paper describes the first “road” results obtained within the SEPOR project, which is focused on developing a low noise poroelastic road surface based on bituminous binder....
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Certification of vehicles used for tire/road noise evaluation by CPX method
PublicationJednym ze sposobów oceny hałasu opon i nawierzchni drogowych jest metda CPX polegająca na pomiarze hałasu w polu bliskim miejsca współpracy opony z nawierzchnią. Aby uzyskać wysoką dokładność pomiarów niezbędne jest ustanowienie procedur ustanowienie procedur certyfikacyjnych sprzętu pomiarowego a więc głównie pojazdu badawczego. Praca dotyczy procedur certyfikacyjnych wypracowanych przez Grupę Roboczą WG33 ISO/TC43/SC1 oraz w...
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Barkhausen noise properties measured by different methods for deformed Armco samples
PublicationPorównano właściwości sygnału napięciowego efektu Barkhausena (BN) uzyskanego za pomocą 'sondy punktowej' (użytecznej dla badań przemysłowych) oraz cewki otaczającej badany materiał. W pierwszej metodzie mierzono trzy wielkości: V1 - napięcie skuteczne, Nc - liczba impulsów, V2 - napięcie kontrolne z cewki. W drugiej metodzie z napięcia indukowanego w cewce wyznaczano pętlę histerezy B(H), obwiednie z napięcia skutecznego a także...
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Investigation of noise threats and their impact on hearing in selected schools - a pilot study.
PublicationNoise 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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High quality speech codec employing sines+noise+transients model
PublicationA method of high quality wideband speech signal representation employing sines+transients+noise model is presented. The need for a wideband speech coding approach as well as various methods for analysis and synthesis of sines, residual and transient states of speech signal is discussed. The perceptual criterion is applied in the proposed approach during encoding of sines amplitudes in order to reduce bandwidth requirements and...
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Tire/road noise measuring principles according to the Close Proximity Method
PublicationW pracy podano metody badania hałasu opon samochodowych. Omówiono przyczepy pomiarowe zbudowane w Politechnice Gdańskiej oraz systemy pomiarowe stosowane do pomiaru hałasu opon zgodnie z metodą CPX.
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Quality assessments of electrochromic devices: the possibleuse of 1/f current noise
PublicationElementy 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...
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Reduction of Influence of the High-Frequency Noise on the Results of Surface Topography Measurements
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Methods and means of processing discrete information in networks with a high level of noise
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Certification requirements for tram noise measurements in terms of today’s expectations in cities
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Implementation of constant component filter in measurements of random telegraph signal noise
PublicationNoise is generated in all semiconductor devices. The intensity of these fluctuations depends on used elements, manufacturing process, operating conditions and device type. The result noise is a superposition of different kinds of fluctuations like thermal noise, generation-recombination noise, 1/f noise, shot noise and Random Telegraph Signal (RTS) noise. The last one, RTS noise is observed as nonstationary impulse fluctuations....
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Evaluation of reinforcement corrosion rate in concrete structures by electrochemical noise measurements
PublicationW pracy przedstawiono wyniki obliczeń rezystancji polaryzacyjnej w układzie złożonym z dwóch elektrod (ze stali węglowej oraz elektrody odniesienia), umieszczonych w otulinie betonowej. Szybkość korozji ulega zmianom uzależnionym od stopnia nasiąknięcia betonu roztworem zawierającym jony chlorkowe. Zmiany rezystancji polaryzacyjnej elektrody stalowej oceniane są na podstawie pomiarów prądowego i potencjałowego szumu elektrochemicznego....
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Low-frequency noise in ZrS3 van der Waals semiconductor nanoribbons
PublicationWe report the results of the investigation of low-frequency electronic noise in ZrS3 van der Waals semiconductor nanoribbons. The test structures were of the back-gated field-effect-transistor type with a normally off n-channel and an on-to-off ratio of up to four orders of magnitude. The current–voltage transfer characteristics revealed significant hysteresis owing to the presence of deep levels. The noise in ZrS3 nanoribbons...
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Creating Dynamic Maps of Noise Threat Using PL-Grid Infrastructure
PublicationThe paper presents functionality and operation results of a system for creating dynamic maps of acoustic noise employing the PL-Grid infrastructure extended with a distributed sensor network. The work presented provides a demonstration of the services being prepared within the PLGrid Plus project for measuring, modeling and rendering data related to noise level distribution in city agglomerations. Specific computational environments,...
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Rolling resistance and tyre/road noise on rubberised asphalt pavement in Poland
PublicationThe 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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The importance of the bottom layer in double-layer porous asphalt for noise reduction
PublicationDouble-layer porous asphalt concrete (DPAC) surfaces are generally considered to be the acoustically most effective low noise road surfaces ready for implementation. While DPAC used on highways in warm climates may have an average life of around 8 years, in Scandinavia with severe winter climate DPAC usually survive only about 3 years; partly due to wear of studded tyres. An ongoing project in Sweden, applying DPAC and single-layer...
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Reduction of road traffic noise by source measures — present and future strategies
PublicationThe current trend worldwide is less focused on reducing road traffic noise. This is in strong contrast to the severe impact of traffic noise to the general health and quality of life. A more holistic and combined strategy is needed. Current international rules and regulations regarding vehicles and tyres are not sufficient to reduce traffic noise levels in an effective way. Calculations show that these regulations will only yield...
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ROSANNE Project: New Procedure for Noise Characterisation of Road Surfaces in Europe
PublicationROSANNE 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,...
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Signal conditioning for examination of shallow-water acoustic noise correlation properties
PublicationThe article describes the process of signal conditioning for examination of acoustic noise correlation properties in shallow water. Knowledge of these properties is very important for the design processes of passive and active hydroacoustic systems. This paper focuses on the above issue from the point of view of passive sonar. In sonar systems, signal processing algorithms operate on both useful acoustic signals, and accompanying...