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Search results for: underwater acoustic communications
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Badanie wierności brzmienia dźwięku instrumentów wirtualnych VST/TRTAS
PublicationTematem referatu jest subiektywne badanie wierności brzmienia instrumentów wirtualnych (VST/TRTAS) wykorzystujących próbkowanie dźwięków rzeczywistych instrumentów muzycznych. Na potrzeby przedstawionej pracy wybrano kilka utworów muzyki orkiestrowej z epoki romantyzmu i klasycyzmu, nagranych przy użyciu instrumentów akustycznych. Następnie zaaranżowano fragmenty tych utworów, wykorzystując do tego instrumenty wirtualne i efekty...
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Ruch wirowy wywoływany przez ultradźwięk w płynach z relaksacją
PublicationRozprawa doktorska poświęcona jest badaniu ruchu wirowego wywoływanego przez ultradźwięk w różnych modelach płynów z relaksacją. Ma ona charakter teoretyczny, jednak wykorzystanie uzyskanych dzięki niej wyników może przynieść lepsze zrozumienie ruchu wirowego wywoływanego przez siłę akustyczną. W I rozdziale rozprawy przedstawione zostały ogólne rozważania dotyczące akustyki nieliniowej. Rozdział II dotyczy ruchu wirowego wywoływanego...
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EMISJA AKUSTYCZNA JAKO SYGNAŁ DIAGNOSTYCZNY ODWZOROWUJĄCY ZMĘCZENIOWE ZUŻYCIE WARSTW ŚLIZGOWYCH PANWI ŁOŻYSK GŁÓWNYCH I KORBOWYCH SILNIKÓW O ZAPŁONIE SAMOCZYNNYM
PublicationW artykule przedstawiono wyniki badań laboratoryjnych, z których wynika, że emisja akustyczna (EA) może być uznana za sygnał diagnostyczny, przydatny do identyfikacji stanu technicznego łożysk głównych i korbowych okrętowych silników o zapłonie samoczynnym. Wykazano w nim bowiem, że parametry emisji akustycznej takie jak: czas rejestracji, energia sygnału, amplituda sygnału, ilość przekroczeń poziomu dyskryminacji, czas narastania,...
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Code development of a DSP-FPGA based control platform for power electronics applications
PublicationThis paper focuses on the implementation of power electronics algorithms in control platforms based on DSP-FPGA. Today’s power electronics technology demands high power computation with high speed interfacing at the same time. The most popular configuration is a DSP for the former and a FPGA for the latter. The main goal of this work was to develop a generic control system for power electronics application, but it is explained...
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Wireless Link Selection Methods for Maritime Communication Access Networks—A Deep Learning Approach
PublicationIn recent years, we have been witnessing a growing interest in the subject of communication at sea. One of the promising solutions to enable widespread access to data transmission capabilities in coastal waters is the possibility of employing an on-shore wireless access infrastructure. However, such an infrastructure is a heterogeneous one, managed by many independent operators and utilizing a number of different communication...
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Influence of Natural Conditions on the Imaging of the Bottom of the Gdańsk Bay by Means of the Side Scan Sonar
PublicationThe interest in underwater resources is the reason for the development of modern hydroacoustic systems, including side sonars, which find numerous applications such as: research of seabed morphology and sediment characteristics, preparation of sea sediment maps, and even in special cases of biocenoses such as sea grass meadows, detection of specific targets at the bottom such as shipwrecks, mines, identification of suitable sites...
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Mathemathical model of radial passive magnetic bearing
PublicationIn the article mathematical radial model of passive magnetic bearings to ocean engineering units has been presented. The units application in underwater thrusters should increase propulsion systems durability and gives lower maintenance costs. The rotor of electric motor is hanging in magnetic field taken from radial passive magnetic bearings. However axial direction maintenance must be controlled with electromagnets and their...
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Web-based 3D processing and dissemination of multibeam sonar data
PublicationThe continuous detailed surveys of the various water bodies over time produce a large and ever-increasing volume and density of underwater sounding data. Three-dimensional data, such as those obtained by multibeam sonar systems, are quite complex to manage, and thus their growing numbers increase the pressure on development of new solutions dedicated to processing them. This paper presents a concept system for web-based dissemination...
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Application of TMS320c67xx signal processors for SONIC-self-optimizing narrowband interference canceler
PublicationThe 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...
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Application of dynamic time warping and cepstrograms to text-dependent speaker verification
PublicationThis work provides a description of an automatic speaker verification (ASV) system. In particular, it documents the evolution of all individual stages of the proposed ASV system design from the phase of preprocessing to an operational decision making system. The aim of this research was to achieve the system of the best safety and ease of use in view of users. The objective estimation of this target has been accomplished by assessing...
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TIRE/ROAD NOISE AND TIRE ROLLING RESISTANCE ON PROTOTYPE PERS SURFACE
PublicationPoroelastic road surfaces are characterized by low noise of tires running on them.Road pavements of this type are promising solution to problems related to traffic noise in cities and on rural roads. Some technical problems still have to be solved, in particular regarding durability and skid resistance on wet surface. Ongoing and planned works are to contribute to create a quiet, durable and safe road surface, which will become...
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Unusual streaming in chemically reacting gases
PublicationNonlinear stimulation of the vorticity mode caused by losses in the momentum of sound in the chemically reacting gas, is considered. The instantaneous dynamic equation which describes the nonlinear generation of the vorticity mode, is derived. It includes a quadratic nonlinear acoustic source. Both periodic and aperiodic sound may be considered as the origin of the vorticity flow. In the non-equilibrium regime of the chemical reaction,...
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Personal adaptive tuning of mobile computer audio
PublicationAn integrated methodology for enhancing audio quality in mobile computers is presented. The key features are adaptation of the characteristics of the acoustic track to the changing conditions and to the user's individual preferences. Original signal processing algorithms are introduced, which concern: linearization of frequency response, dialogue intelligibility enhancement and dynamics processing tuned up to the user's preferences....
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Acoustics - new services for urban planning, research and education
PublicationThe main purpose of the presented design is twofold, namely: providing detailed information about the noise threats that occur every day in city areas and preventing the noise induced hearing loss especially among young people. An experimental system designed for the continuous monitoring of the acoustic climate of urban areas was developed and implemented within the PLGrid Plus project. The assessment of environmental threats...
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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
PublicationThis 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,...
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Noise effect on parameters of quiet sonar with code modulation
PublicationEarlier 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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On the Nonlinear Effects of Magnetoacoustic Perturbations in a Perfectly Conducting Viscous and Thermoconducting Gas
PublicationNonlinear effects of planar and quasi-planar magnetosound perturbations are discussed. The plasma is as- sumed to be a Newtonian thermoconducting gas with infinite electrical conductivity permeated by a magnetic field orthogonal to the trajectories of gas particles. Generation of the non-wave modes (magnetoacoustic heating and streaming) in the field of periodic and aperiodic magnetoacoustic perturbations is discussed. The results...
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Standing Waves in One-Dimensional Resonator Contaning an Ideal Isothermal Gas Affected by the Constant Mass Force
PublicationThe study is devoted to standing acoustic waves in one-dimensional planar resonator which containing an ideal gas. A gas is affected by the constant mass force. Two types of physically justified boundary conditions are considered: zero velocity or zero excess pressure at both boundaries. The variety of nodal and antinodal points is determined. The conclusion is that the nodes of pressure and antinodes of velocity do not longer...
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Examples of AFM applications in liquid environment
Open Research DataImportant advantage of atomic force microscopy (also tunneling microscopy) is the ability to work in different environments (vacuum, controlled atmosphere, liquid environment). The last one, open interesting possibilities, such as imaging of delicate biological materials in their natural state. The use of electrochemical mode allows for the modification...
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Jakub Grochowski mgr inż.
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In silico study on the effects of carbonyl groups on chemical equilibrium of reactions with a polar product occurring under confinement in pores of activated carbons
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Influence of phonon-phonon coupling on superconducting state in honeycomb-type crystal lattice
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ARUZ — Large-scale, massively parallel FPGA-based analyzer of real complex systems
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Superconducting state in the atomic metallic hydrogen just above the pressure of the molecular dissociation
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The superconducting state in the B2H6 compound at 360GPa
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Description of the thermodynamic properties of BiH 5 and BiH 6 superconductors beyond the mean-field approximation
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First-order impulsive functional differential equations
PublicationPraca dotyczy problemów istnienia rozwiązań i kwazi-rozwiązań dla równań różniczkowych rzędu pierwszego z impulsami i nieliniowymi warunkami brzegowymi. Operator występujący w zagadnieniu jest typu opóźnionego. Badano również nierówności różniczkowe z impulsami związane z zagadnieniem wyjściowym. Otrzymane wyniki zilustrowano na przykładach.
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Magnetic Molecularly Imprinted Polymer Particles Synthesized by Suspension Polymerization in Silicone Oil
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Synthesis and photochemical properties of unsymmetrical phthalocyanine bearing two 1-adamantylsulfanyl groups at adjacent peripheral positions
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The influence of of cross-linking process on the physicochemical properties of new copolyesters containing xylitol
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Synthesis, characterization, photochemical properties and cytotoxicity of the novel porphyrazine functionalized with nitroimidazolylbutylsulfanyl groups
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Synthesis, spectroscopic and photophysical properties of novel styryldiazepinoporphyrazine
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The exponential law for partial, local and proper maps and its application to otopy theory
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Erbium (III) molybdate as a new nanofiller for fabrication of antifouling polyethersulfone membranes
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Efficient parallel algorithms in global optimization of potential energy functions for peptides, proteins, and crystals
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k-Penalty: A Novel Approach to Find k-Disjoint Paths with Differentiated Path Costs
PublicationW artykule rozpatrywany jest problem ochrony dedykowanej na wypadek awarii wielokrotnej elementów sieci teleinformatycznej. Wspomniana ochrona jest możliwa do zapewnienia poprzez wyznaczenie i zainstalowanie zbioru k rozłącznych ścieżek dla każdego żądania. W szczególności rozpatrywany jest problem wyznaczenia k rozłącznych ścieżek w sieciach typu ''multi-cost'', w przypadku których koszt dowolnego łącza może być różny dla każdej...
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Novel zinc complexes with acetyloacetonate, imidazole and thiolate ligands: Crystal structure of a zinc complex of relevance to farnesyl transferase
PublicationOtrzymano dwa nowe kompleksy cynku z ligandami S-,N- i O-donorowymi i scharakteryzowano je za pomocą rentgenowskiej analizy strukturalnej i spektroskopii w podczerwieni. Jeden z tych kompleksów jest pierwszym kompleksem modelującym centrum aktywne transferazy farnezylu.
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Self-assembly of zinc and cobalt complexes mimicking active site of alcohol dehydrogenase
PublicationPo raz pierwszy zsyntetyzowano obojętne kompleksy cynku i kobaltu naśladujące strukturę centrum aktywnego dehydrogenazy alkoholowej z wodą jako dodatkowym ligandem. Jakość otrzymanych kryształów pozwoliła na szczegółową analizę wewnątrzcząsteczkowych wiązań wodorowych w kryształach tych związków. Wnioski potwierdzono za pomocą spektroskopii FT-IR w ciele stałym.
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In-situ synthesis and characterization of biocompatible magnetic ginger nanofiber composites for copper (II) removal from water
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Magnetic properties of charge ordered complex TCNQ salts with lattice distortions
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Effect of a characteristic length on crack spacing in a reinforced concrete bar under tension
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Chemical instability of the cobalt oxyhydrate superconductor under ambient conditions
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Superconductivity in three-layer Na0.3CoO2·1.3H2O
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The effect of Fe and Ru substitution on the superconductivity in MgCNi3
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Morphology and local chain structure of polyamide 6 modified in the solid state with a semi-aromatic nylon salt
PublicationStructural and conformational differences between the polyamide 6 (PA6) homopolymer and two copolymers of PA6 modified in the solid state with 20 and 30 wt% of the semi-aromatic nylon salt of 1,5-diamino-2-methylpentane (Dytek A) and isophthalic acid (IPA) in the feed were investigated. Room temperature wide-angle X-ray diffraction (WAXD) analysis together with 13C{1H} cross-polarization/magic-angle spinning solid-state (CP/MAS)...
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A highly-efficient technique for evaluating bond-orientational order parameters
PublicationWe propose a novel, highly-efficient approach for the evaluation of bond-orientational order parameters (BOPs). Our approach exploits the properties of spherical harmonics and Wigner 3jj-symbols to reduce the number of terms in the expressions for BOPs, and employs simultaneous interpolation of normalised associated Legendre polynomials and trigonometric functions to dramatically reduce the total number of arithmetic operations....
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Traffic Remapping Attacks in Ad Hoc Networks
PublicationAd hoc networks rely on the mutual cooperation of stations. As such, they are susceptible to selfish attacks that abuse network mechanisms. Class-based QoS provisioning mechanisms, such as the EDCA function of IEEE 802.11, are particularly prone to traffic remapping attacks, which may bring an attacker better QoS without exposing it to easy detection. Such attacks have been studied in wireless LANs, whereas their impact in multihop...
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Mononuclear sodium(I) and copper(I) silanethiolates
PublicationStericallyencumberedligand(ArO) 3 SiS − , where Ar = 2,6-diisopropylphenyl, was employed for the synthesisof a dicoordinate copper(I) complex. The ligand creates a very hydrophobic environment around the metal center as indicated by the crystal structures and FT-IR spectroscopy.
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On the material symmetry group for micromorphic media with applications to granular materials
PublicationWithin the framework of the theory of nonlinear elastic micromorphic continua we introduce the new definition of the local material symmetry group. The group consists of ordered triples of second- and third-order tensors describing such changes of a reference placement that cannot be recognized with any experiment. Using the definition we characterize the micromorphic isotropic media, micromorphic fluids, solids and special intermediate...
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ICUMT 2011 Congress in Budapest, Hungary
Publicationartykuł sprawozdawczy z konferencji