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The influence of screw configuration and screw speed of co-rotating twin screw extruder on the properties of products obtained by thermomechanical reclaiming of ground tire rubber
PublikacjaThe results of our investigations on the process of continuous thermomechanical reclaiming of ground tire rubber (GTR) carried out using a twin screw extruder are presented.We used a co-rotating twin screw extruder with a special configuration of plasticizing unit, enabling generation of considerable shear forces. The influence of screw configuration and screw speed on breaking of chemical crosslink bonds contained in ground tire...
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Comparative Study of Pavement Rehabilitation Using Hot in-Place Recycling and Hot-Mix Asphalt: Performance Evaluation, Pavement Life Prediction, and Life Cycle Cost Analysis
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Tyre/road noise reduction of poroelastic road surface tested in a laboratory
PublikacjaA so-called poroelastic road surface (PERS) is being developed in Europe. This contains a large percentage of rubber particles mixed with hard aggregate (stone and sand) and bound with polyurethane. This gives high air void content (around 30 %), high elasticity and smooth texture, all of which should give low noise properties. Inthis experiment anominally 30 mm thick sample of PERS was mounted on a steel drum. Various car tyres...
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Deflection measurement of field section with pavement with base course made of Cement Bitumen Treated Material Mixture C3E4 (28, 180, 270, 365 days after compaction)
Dane BadawczeDataset presents data of deflections determined for pavement with base course made of cold recycled mixture – cement bitumen treated material mixture with following binding agents: 3% cement, 4% emulsion (C3E4). Mixture was designed according to Polish requirements for the base course of pavement. Mixture was mixed in stationary plant and compacted...
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ESTIMATION OF NONSTATIONARY HARMONIC SIGNALS AND ITS APPLICATION TO ACTIVE CONTROL OF MRI NOISE
PublikacjaA new adaptive comb filtering algorithm, capable of tracking the fundamental frequency and amplitudes of different frequency components of a nonstationary harmonic signal embedded in white measurement noise, is proposed. Frequency tracking characteristics of the new scheme are studied analytically, proving (under Gaussian assumptions and optimal tuning) its statistical efficiency for quasi-linear frequency changes. Laboratory tests...
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Analysis of Lombard speech using parameterization and the objective quality indicators in noise conditions
PublikacjaThe 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...
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Cheap Cancellation of Strong Echoes for Digital Passive and Noise Radars
PublikacjaThe 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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Parametric impulsive noise detector for corrupted audio signals based on hidden Markow model
PublikacjaThe paper addresses the problem of impulsive noise detection for audio signals. A structure of threshold parameter detectors using modelingof signals was introduced. the algorithm of the noise detection, based on discrete-time hidden Markow model (HMM)of whitened audio signal is elaborated
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Noise Generated by Tyres Designet for Electric Vehicles - Results of Laboratory Experiments
PublikacjaA few years ago, electric and hybrid vehicles were rarely seen on public roads and were considered more as exotic curiosities or even as a sign of extravagance than a practical means of transport. Nowadays the situation has changes significantly. This was caused both by the technical development and legislative actions, as well as the organizational nature promoting the purchace and use of low emission vehicles. Electric vehicles...
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Audible noise in ship’s electrical drive systems with frequency converters
Dane BadawczeThe presented dataset is part of research focusing on the impact of the ship's electrical drive systems with frequency converters on vibrations and the level of audible noise on ships.
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Insights into Stoichiometry Adjustments Governing the Performance of Flexible Foamed Polyurethane/Ground Tire Rubber Composites
PublikacjaPolyurethanes (PU) are widely applied in the industry due to their tunable performance adjusted by changes in the isocyanate index—stoichiometric balance between isocyanate and hydroxyl groups. This balance is affected by the incorporation of modifiers of fillers into the PU matrix and is especially crucial for PU foams due to the additional role of isocyanates—foaming of the material. Despite the awareness of the issue underlined...
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Curing characteristics, mechanical properties and morphology of butyl rubber filled with ground tire rubber (GTR)
PublikacjaThe results on testing application of ground tire rubber (GTR), as potential filler for butyl rubber, are pre- sented. The GTR content variation, within the range of 10–90 phr, was studied with respect to the vulcanization process, static mechanical properties (tensile strength, elongation-at-break, hardness and resilience), dynamic mechanical properties and the morphology of the obtained vulcanizates. Butyl rubber was characterized...
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The Impact of Hybrid Flame Retardant Compositions on the Performance of Foamed Flexible Polyurethane/Ground Tire Rubber Composites
PublikacjaCurrent sustainability-oriented trends affect polyurethane (PU) materials and stimulate the incorporation of recycled or waste-based materials as fillers. Ground tire rubber (GTR) poses as an auspicious candidate due to the excellent performance of car tires. Despite the benefits related to the mechanical performance, it contributes to the increasing flammability of the resulting composites. Herein, presented work assessed the...
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A new methodological approach to the noise threat evaluation based on the selected physiological properties of the human hearing system
PublikacjaA new way of assessment of noise-induced harmful effects on human hearing system is presented in the paper. The method takes into consideration properties of the selected physiological human hearing system. On the basis of the hearing examinations and noise measurements results and psychoacoustical noise dosimeter performance the new indicators of the noise harmfulness were proposed. The evaluation of the proposed indicators were...
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Realistic noise-tolerant randomness amplification using finite number of devices
PublikacjaRandomness 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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IT- Enabled Comparison of Environmental Noise Levels and Noise-Evoked Hearing Impairments.
PublikacjaTematem pracy jest telemetryczny system monitorowania hałasu, opracowany w katedrze Systemów Multimedialnych Politechniki Gdańskiej, przeznaczony do zdalnego monitorowania poziomów hałasu środowiskowego. Oprócz ogólnej charakterystyki systemu zaprezentowano również szereg szczegółów implementacyjnych. Przedstawiono m.in. mobilne urządzenie pomiarowe, oprogramowanie do pomiarów hałasu, dźwiękowy interfejs USB wyposażony w mikrofon...
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IT- enabled comparison of environmental noise levels and noise-evoked hearing impairments.
Publikacja[Abstrakt] Tematem pracy jest telemetryczny system monitorowania hałasu, opracowany w katedrze Systemów Multimedialnych Politechniki Gdańskiej, przeznaczony do zdalnego monitorowania poziomów hałasu środowiskowego. Oprócz ogólnej charakterystyki systemu zaprezentowano również szereg szczegółów implementacyjnych. Przedstawiono m.in. mobilne urządzenie pomiarowe, oprogramowanie do pomiarów hałasu, dźwiękowy interfejs USB wyposażony...
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Noise Scattering Patterns Method for Recognition of RTS Noise in Semiconductor Components
PublikacjaOpisano nową metodę identyfikacji i wizualizacji szumów RTS. Metoda ta oparta na graficznym przedstawieniu przebiegu szumowego jest szczególnie użyteczna do szybkiej selekcji elektronicznych elementów półprzewodnikowych. Przedstawiono także rezultaty filtacji medianowej szumu zawierającego składową RTS. Filtrację medianową zastosowano do poprawienia obrazu szumu uzyskanego w wyniku zastosowania metody NSP.
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Noise as stimulus signal for digital circuits noise immunity measurementand simulation
PublikacjaWyniki pomiarów podatności na zakłócenia układów cyfrowych istotnie zależą od parametrów sygnału stymulujacego. Przedstawiono metodę pomiaru i symulacji dynamicznej odporności na zakłócenia z zastosowaniem sygnału szumu białego o różnej szerokości pasma częstotliwości. Modele symulacyjne dla sygnału pobudzającego (gaussowskiego szumu białego) zarówno szerokopasmowego jak i wąskopasmowego opracowano w środowisku programistycznym...
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Noise modeling of static CMOS gates for low-noise circuit synthesis
PublikacjaW artykule przedstawiono efektywną metodę modelowania widma szumu napięcia zasilającego generowanego przez statyczne bramki cyfrowe CMOS. Metoda modelowania uwzględnia krótkie impulsy prądowe powstające w czasie przełączania bramek i pozwala oszacować górne limity widma szumu napięcia zasilającego co umożliwia niskoszumową syntezę układów cyfrowych.
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Effect of Compounding Conditions on Static and Dynamic Mechanical Properties of High Density Polyethylene/Ground Tire Rubber Blends
PublikacjaSearching for new and cost-effective methods of waste rubber recycling is a subject of research in many scientific centers in the world. In this paper there are presented results of the research of the extrusion process of cheap and environmentally friendly thermoplastic compositions containing 50 % wt. of masses of ground tire rubber (GTR). The aim of this study was to determine the relationship between the mixing conditions and...
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Quality assessments of electrochromic devices: the possibleuse of 1/f current noise
PublikacjaElementy 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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Improving asphalt pavement intelligent compaction based on differentiated compaction curves
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Field investigation and numerical analysis of an inverted pavement system in Tennessee, USA
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Accelerated Pavement Testing to Evaluate the Reinforcement Effect of Geogrids in Flexible Pavements
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Ground tire rubber thermo-mechanically devulcanized in the presence of waste engine oil as asphalt modifier
PublikacjaCross-linked elastomers network is main limitation for industrial usage of ground tire rubber (GTR) as asphalts’ and road pavements modifier. GTR was thermo-mechanically devulcanized via extrusion in the presence of waste engine oil (WEO) at temperature ranges from 150 to 280 °C. Combined impact of WEO content and extruder barrel temperature on the change of cross-linked structure of degraded GTR (DTGR) was investigated through...
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Tyre/road noise of passenger car tyres, including tyres for electric vehicles - road measurements
PublikacjaThe paper presents the results from CPX measurements of tyre/road noise performed for selected passenger car tyres, including the tyres especially designed for electric vehicles. The tyres have been measured when rolling on several typical road surfaces in Norway and in Poland. In addition, the tyres have been measured on some very low noise road surfaces, such as a the poroelastic road surface (PERS). The measurement results...
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Noise in semiconductor devices
PublikacjaOmówiono typowe źródła szumów występujące w przyrządach pólprzewodnikowych, a mianowicie: cieplne, śrutowe, generacyjno-rekombinacyjne, 1/f, 1/f2, wybuchowe (RTS), lawinowe. Przedstawiono szumowe schematy zastępcze tranzystora bipolarnego, JFET i MOSFET oraz opisano wydajności poszczególnych źródeł szumów. Zasugerowano jak dobierać przyrządy półprzewodnikowe do małoszumowych układów w zakresie małych częstotliwości.
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Numerical Model of Surface and Quasi-Spherical Sea Noise and Its Application to Analysis of DIFAR Systems
PublikacjaVarious types of passive sonar systems are used to detect submarines. These activities are complex and demanding. Therefore, computer simulations are most often used at the design stage of these systems. For this reason, it is also necessary to simulate the acoustic ambient noise of the sea. The article proposes a new numerical model of surface and quasi-spherical sea noise and presents its statistical parameters. The results of...
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Complex Predictive Solution for Computerized Processes in Tire Industry
PublikacjaFollowing increasing market needs of productivity, cost reduction and safety requirements, computerized industry are faced to finding optimum between economic aspects of business and safety-related risk management. Modern factories equipped with computerized processes and extended diagnostic tools to support operator do not often use of all information’s which comes from the equipment. Some of the relations between the events are...
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Approximate Cramér–Rao bound on Doppler error in correlation-processing relatively narrowband noise radar
PublikacjaThe paper studies limitations on accuracy of Doppler estimation in continuous-wave noise radar with correlation processing. Second order properties of output of the correlation receiver are evaluated and an approximate Cram´er-Rao bound on errors of Doppler measurement is derived. The accuracy of Doppler measurements is found to be affected by the following factors: power spectral density of noise signal, frequency response of the...
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Identification of acoustic event of selected noise sources in a long-term environmental monitoring systems
PublikacjaABSTRACT 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...
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Ground Tire Rubber Modified by Elastomers via Low-Temperature Extrusion Process: Physico-Mechanical Properties and Volatile Organic Emission Assessment
PublikacjaIn this paper, low-temperature extrusion of ground tire rubber was performed as a proecological waste tires recycling method. During this process, ground tire rubber was modified with constant content of dicumyl peroxide and a variable amount of elastomer (in the range: 2.5–15 phr). During the studies, three types of elastomers were used: styrene-butadiene rubber, styreneethylene/butylene-styrene grafted with maleic anhydride and...
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Detection, classification and localization of acoustic events in the presence of background noise for acoustic surveillance of hazardous situations
PublikacjaEvaluation of sound event detection, classification and localization of hazardous acoustic events in the presence of background noise of different types and changing intensities is presented. The methods for discerning between the events being in focus and the acoustic background are introduced. The classifier, based on a Support Vector Machine algorithm, is described. The set of features and samples used for the training of the...
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"Creating a numerical model of noise conditions based on the analysis of traffic volume changes in cities with low and medium structure.
PublikacjaThe subject of this research study is to analyze noise conditions of the selected area in the city of Gdańsk using data related to traffic volume changes during a day. This is because daily distribution of noise levels is much more helpful for noise control and reduction than traditional maps with Lden levels indicated. Calculations are made with the use of a numerical model developed at the Gdansk Univ. of Technology and implemented...
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"Creating a numerical model of noise conditions based on the analysis of traffic volume changes in cities with low and medium structure.
PublikacjaThe subject of this research study is to analyze noise conditions of the selected area in the city of Gdańsk using data related to traffic volume changes during a day. This is because daily distribution of noise levels is much more helpful for noise control and reduction than traditional maps with Lden levels indicated. Calculations are made with the use of a numerical model developed at the Gdansk Univ. of Technology and implemented...
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Chemical surface etching methods for ground tire rubber as sustainable approach for environmentally-friendly composites development– a review
PublikacjaGround tire rubber (GTR) has been used as a sustainable low-cost modifier in various composites. However, due to the hydrophobic nature of GTR, it is in compatible with most matrices and results in deterioration in both mechanical and physical properties of composites. This necessitates pre-modification of the powdered rubber to improve the interfacial bonding at the rubber-matric interface. The most common GTR modification research...
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Temperature influence on tyre/road noise on poroelastic road surface based on laboratory measurements
PublikacjaThe 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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International Journal of Vehicle Noise and Vibration
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Laser-textured cross-hatched surface topography analysis with evaluation of high-frequency measurement noise
PublikacjaThe precision of surface roughness determination using ISO 25178 parameters relies on various factors that directly impact the measurement process. In industry applications, the contactless roughness measurement reduces data collection time. However, it introduces several potential errors, including those stemming from the environment. One of the main types of errors encountered during topography analysis is measurement noise,...
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Structural Changes and Their Implications in Foamed Flexible Polyurethane Composites Filled with Rapeseed Oil-Treated Ground Tire Rubber
PublikacjaThe utilization of post-consumer car tires is an essential issue from an ecological andeconomic point of view. One of the simplest and the least harmful methods is their material recyclingresulting in ground tire rubber (GTR), which can be further applied as fillers for polymer-basedcomposites. Nevertheless, insufficient interfacial interactions implicate the necessity of GTR modi-fication before introduction into polymer matrices....
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Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
PublikacjaWe report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle...
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Selective monitoring of noise emitted by vehicles involved in road traffic
PublikacjaAn acoustic intensity probe was developed measures the sound intensity in three orthogonal directions, making possible to calculate the azimuth and elevation angles, describing the sound source position. The acoustic sensor is made in the form of a cube with a side of 10 mm, on the inner surfaces of which the digital MEMS microphones are mounted. The algorithm works in two stages. The first stage is based on the analysis of sound...
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Investigation of RTS Noise in Reverse Polarized Silicon Carbide Schottky Diodes
PublikacjaOne of the method of electronic device quality and reliability evaluation is observation of its inherent noise. The RTS phenomena usually indicates the presence of large defects in the structure of the material of the device, therefore it can be treated as an indicator of technology quality. In the paper authors present results of RTS investigations in reverse polarized Silicon Carbide Schottky diodes. Devices being studied are...
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Resilient Interface Shear Modulus for Characterizing Shear Properties of Pavement Base Materials
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Evaluation of inverted pavement by structural condition indicators from falling weight deflectometer
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Coal-derived conductive pavement for winter de-icing: prototype, modeling, and simulation
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Impact of reclaimed asphalt pavement (RAP) on low-temperature properties of asphalt concrete
PublikacjaHot mix recycling is a practice which enables reusing materials from old asphalt pavements. Current Polish regulations allow usage of RAP only for binder and base courses, and its amount is limited. Asphalt mixtures with RAP material have to fulfil requirements stated for typical asphalt mixtures. The research presents low-temperature properties of twelve different asphalt concretes with RAP material, determined using three-point...
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Three solvers for MIMO noise radar clutter cancellation - a performance comparison
PublikacjaThe problem of canceling strong clutter echos in a MIMO noise radar is considered. Execution times of three algorithms is compared. The first solution is a standard Least Squares approach employing Cholesky decomposition of the transmitted signal sample autocorrelation matrix. The second approach is based on careful waveform design which guarantees that the signal sample autocorrelation matrix has Toeplitz structure. This enables...
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Shipping Low Frequency Noise and Its Propagation in Shallow Water
PublikacjaOne 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....