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Search results for: UNDERWATER ACOUSTIC COMMUNICATION
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Generation of vorticity motion by sound in a chemically reacting gas and inversion of acoustic streaming in the non-equilibrium regime
PublicationBadanie dotyczy nieliniowych pobudzeń modu wirowego wywoływanych przez straty momentu pędu w gazie, w którym zachodzą reakcje chemiczne. Zostało wyprowadzone chwilowe dynamiczne równanie dla modu wirowego. Zawiera ono nieliniową siłę akustyczną co pokazuje, że powodem interakcji między modami akustycznym i wirowym jest nieliniowość. Równanie pozwala jako przyczynę ruchu wirowego rozważać zarówno dźwięk okresowy, jak i aperiodyczny....
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Development of linear projecting in studies of non-linear flow. Acoustic heating induced by non-periodic sound
PublicationRównanie bilansu energii rozkłada się na sumę dwóch równań, opisujących dynamikę fali akustycznej i wywołanego przez nią ogrzewania. Nowe równanie dynamiczne stosowane jest dla opisu dźwięku nieokresowego zarówno jak okresowego. Rozpatruje się geometrię wiązkową. Omówiane są poszczególne udziały przewodnictwa cieplnego i lepkości w ogrzewaniu akustycznym. Równania stanu ośrodka propagacji są uwzględniane w najbardziej ogólnej postaci.
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Application of Rock Solid Attributes for robust identyfication of glass breaks acoustic signals via wavelet transformation
PublicationWspółczesne metody detekcji zbicia szyby stosowane w systemach alarmowych, wykorzystują analizę sygnałów akustycznych (ze względu na osiągi i koszty). Często używane metody analizy bazują na detekcji kilku charakterystycznych częstotliwości, jednak nie są to metody odporne na sygnały fałszywe. Jak wskazują niektóre pozycje literatury, zastosowanie metod JTFA może być bardziej użyteczne do analizy tego rodzaju sygnałów. Aby opracować...
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Effect of Amino Acids and Sodium Chloride on d-Sorbitol in Aqueous Solutions at Different Temperatures: Volumetric and Acoustic Approach
PublicationApparent molar volumes and apparent molar compressibilities for d-sorbitol in (0.05, 0.1, 0.2 and 0.3) mol·kg−1 aqueous solutions of l-alanine, l-cysteine and l-histidine and NaCl have been determined from measurements of solution density at T = (288.15, 298.15, 308.15 and 318.15) K and sound velocity at T = 298.15 K, as a function of the concentration of the sugar alcohol. The data were used to obtain the limiting apparent molar...
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Analiza akustyczna jako parametr klasyfikacji formalnej homonimii międzyjęzykowej [The acoustic analysis as a parameter for classifying interlingual homonymy]
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Solvation of alkaline earth metal ions in N,N-dimethylformamide and N,N-dimethylacetamide – A volumetric and acoustic study
PublicationDensities and sound velocities at temperatures (298.15, 303.15, 308.15, 313.15 and 318.15) K of magnesium(II), calcium(II) and strontium(II) rifluoromethanesulfonates (triflates), as well as barium(II) perchloratein N,N-dimethylformamide (dmf) and N,N-dimethylacetamide (dma) have been measured over the composition range studied. From these results, apparent molar volumes and apparent molar isentropic compressibilities at infinite...
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Methods of quality assessment and analysis of data given in customer service process on example of selected urban communication organization - result of research 2016
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Human Umbilical Vein Endothelial Cells (HUVECs) Co-Culture with Osteogenic Cells: From Molecular Communication to Engineering Prevascularised Bone Grafts
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Investigations on the influence CuO doping on elastic properties of Li2SO4–MgO–P2O5 glass system by means of acoustic wave propagation
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Influence of NiO doping on elastic properties of Li2SO4-MgO-P2O5 glass system-Investigation by means of acoustic wave propagation
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The evaluation methodology of corrosion protection of tanks from hull structural steels with Acoustic Emission use and first results of investigations
PublicationW referacie przedstawiono metodykę badań mającą na celu ocenę stopnia ochrony przed korozją konstrukcji zbiorników ładunkowych i balastowych wykonanych ze stali kadłubowych z wykorzystaniem Emisji Akustycznej (EA). W metodyce wykorzystano wymagania obowiązujących norm, standardów oraz doświadczenia zdobyte w dotychczasowych badaniach poświęconych zastosowaniu metody EA do wykrywania i lokalizacji źródeł korozji na statkach. Do...
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Dynamics of changes in iron concentration and total iron binding capacity in blood plasma of goat kids during their first month of life (Short Communication)
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Assessing the damage importance rank in acoustic diagnostics of technical conditions of the internal combustion engine with multi-valued logical decision trees
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Volumetric and acoustic properties of D-mannitol in aqueous sodium or magnesium(II) chloride solutions over temperature range of 293.15 to 313.15 K
PublicationWykorzystując zmierzone wartości gęstości oraz prędkości rozchodzenia się dźwięku wyznaczono pozorne objętości molowe i pozorne ściśliwości molowe D- mannitolu w (1, 5 i 10) % wodnych roztworach chlorku sodu oraz chlorku magnezu(II). Obliczono graniczne wartości pozornych wielkości molowych, odpowiednie funkcje przeniesienia oraz współczynniki rozszerzalności. Otrzymane wielkości powiązano z oddziaływaniami D-mannitol -sól (NaCl...
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Solvation of ionic liquids based on N-alkyl-N-methylmorpholinium cations in N,N-dimethylformamide and dimethyl sulfoxide – A volumetric and acoustic study
PublicationApparent molar volumes and molar isentropic compressibilities for N-ethyl-N-methylmorpholinium and N-decyl-N-methylmorpholinium tetrafluoroborates in N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) have been determined from density and speed of sound measurements over the temperature range T = (298.15, 303.15, 308.15, 313.15, 318.15 and 328.15) K at experimental pressure p = 0.1 MPa. This data has been used to calculate...
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Evaluation by means of magneto-acoustic emission and Barkhausen effect of time and space distribution of magnetic flux density in ferromagnetic plate magnetized by a C-core
PublicationPokazano wyniki badań emisji magnetoakustycznej (EMA) i efektu Barkhausena (HEB) dla dwóch płyt stalowych o różnych wymiarach. Wyniki te są porównane z wynikami modelowania zjawiska EMA z wykorzystaniem metody elementów skończonych z uwzględniem efektu prądów wirowych. Uzyskano zadawalające dopasowanie modelu, który odtwarzał poszerzenie maksimum EMA oraz przesunięcie fazowe i zmianę amplitudy HEB.
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Metropolie ery cyfrowej- wpływ nowych technologii informacyjnych i komunikacyjnych na kształt współczesnego miasta = Digital metropolis - the impact of new information and communication technologies on contemporary city
PublicationDynamiczny rozwój technologii informacyjnych i cyfrowych zapoczątkowany w drugiej połowie XX wieku wpłynął na zmianę wizerunku współczesnego miasta. Coraz bardziej wyraźną rolę w jego tworzeniu zaczęły odgrywać fasady, powłoki budynków oraz fragmenty przestrzeni publicznych, w obrębie których zaczęto integrować pojawiające się innowacyjne technologie, potocznie zwane medialnymi. Powierzchnie architektoniczne wyposażone w nie...
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Избранные проблемы контрастивного анализа цифровых акустических изображений лексем разных языков [Selected problems in the analysis of digital acoustic images for lexemes from various languages]
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Избранные проблемы контрастивного анализа цифровых акустических изображений лексем разных языков [Selected problems in the analysis of digital acoustic images for lexemes from various languages]
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Акустическое изображение омонима этнического языка как входной элемент формальной классификации межъязыковой омонимии [The acoustic image of ethnic homonyms as an input element in formal classification of interlinguistic homonymy]
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Акустическое изображение омонима этнического языка как входной элемент формальной классификации межъязыковой омонимии [The acoustic image of ethnic homonyms as an input element in formal classification of interlinguistic homonymy]
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Integrated acoustical-optical system for inventory of hydrotechnical objects
PublicationThe knowledge of the location, shape and other characteristics of spatial objects in the coastal areas has a significant impact on the functioning of ports, shipyards, and other waterinfrastructure facilities, both offshore and inland. Therefore, measurements of the underwater part of the waterside zone are taken, which means the bottom of the water and other underwater objects (e.g. breakwaters, docks, etc.), and objects above...
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Spawalność ferrytyczno-austenitycznej stali odpornej na korozję typu dupleks 2205 w warunkach podwodnych
PublicationPraca dotyczy problemów spawalności stali odpornej na korozję typu dupleks w warunkach spawania mokrego elektrodami otulonymi i lokalną komorą suchą. Całość rozprawy składa się z dwóch części. Część pierwsza to przegląd literatury, w którym omówiono główne problemy wynikające z przeniesienia procesu spawania pod wodę oraz sposoby minimalizowania negatywnego wpływu środowiska. Część druga jest częścią doświadczalną, zawiera tezę...
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Prognozowanie właściwości złączy spawanych pod wodą metodą lokalnej komory suchej
PublicationNiniejsza praca jest poświęcona spawaniu pod wodą metodą lokalnej komory suchej (MLKS) i przedstawia metodologię oraz narzędzia umożliwiające prognozowanie właściwości złączy spawanych wykonanych przy zastosowaniu tej odmiany spawania. Monografia zawiera opis rozwoju spawania pod wodą oraz charakterystykę metod wykorzystywanych do realizacji prac spawalniczych. Zaproponowano nowy podział metod spawania pod wodą, uwzględniający...
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Editorial: Coronavirus disease (COVID-19): Socio-economic systems in the post-pandemic world: Design thinking, strategic planning, management, and public policy
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Patients’ Expectations as to Doctors’ Behaviors During Appointed Visits
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Unfavorable Medical Diagnosis – Oncological Patients’ Experiences and Preferences
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Computer-assisted pronunciation training—Speech synthesis is almost all you need
PublicationThe research community has long studied computer-assisted pronunciation training (CAPT) methods in non-native speech. Researchers focused on studying various model architectures, such as Bayesian networks and deep learning methods, as well as on the analysis of different representations of the speech signal. Despite significant progress in recent years, existing CAPT methods are not able to detect pronunciation errors with high...
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Measurements and visualization of sound field distribution around organ pipe
PublicationMeasurements and visualization of acoustic field around an organ pipe are presented. Sound intensity technique was applied for this purpose. Measurements were performed in free field. The organ pipe was activated with a constant air flow, produced by an external compressor, aimed at obtaining long-term steady state responses of generated acoustic signal. Sound energy distribution was measured in a defined fixed grid of points...
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Modeling and Designing Acoustical Conditions of the Interior – Case Study
PublicationThe primary aim of this research study was to model acoustic conditions of the Courtyard of the Gdańsk University of Technology Main Building, and then to design a sound reinforcement system for this interior. First, results of measurements of the parameters of the acoustic field are presented. Then, the comparison between measured and predicted values using the ODEON program is shown. Collected data indicate a long reverberation...
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Nonlinear Influence of Sound on the Vibrational Energy of Molecules in a Relaxing Gas
PublicationDynamics of a weakly nonlinear and weakly dispersive flow of a gas where molecular vibrational relaxation takes place is studied. Variations in the vibrational energy in the field of intense sound is considered. These variations are caused by a nonlinear transfer of the acoustic energy into energy of vibrational degrees of freedom in a relaxing gas. The final dynamic equation which describes this is instantaneous, it includes a...
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Sound intensity distribution around organ pipe
PublicationThe aim of the paper was to compare acoustic field around the open and stopped organ pipes. The wooden organ pipe was located in the anechoic chamber and activated with a constant air flow, produced by an external air-compressor. Thus, long-term steady state response was possible to obtain. Multichannel acoustic vector sensor was used to measure the sound intensity distribution of radiated acoustic energy. Measurements have been...
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Selective monitoring of noise emitted by vehicles involved in road traffic
PublicationAn 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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Some fundamental aspects of self-levitating sliding contact bearings and their practical implementations
PublicationIn this study, fundamental aspects and mechanisms of acoustic levitation together with governing equations are presented first. Then, the acoustic levitation phenomenon is considered as a new way to design air suspension systems capable of self-levitation. A particular emphasis is laid on journal bearings and their specific geometrical configuration. A practical feasibility of using acoustic levitation to separate contacting surfaces...
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Akustyka sali koncertowej Szkoły Muzycznej w Gdyni - projekt i realizacja
PublicationOmówiono zakres współpracy architekta, akustyka i projektanta wnętrza na przykładzie sali koncertowej Szkoły Muzycznej w Gdyni. Wskazano różnice między projektem akustycznym sali i projektem wnętrza. Podano zasady akustycznego projektowanie sali widowiskowej oraz znaczenie rozproszenia dźwięku dla jakości akustycznej sali. Przedstawiono zasady indywidualnego konstruowania ustrojów rozpraszających dźwięk oraz dostępne na rynku ustroje...
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Non linear identification of underwater vehicles. W: [CD-ROM] Conference Proceedings. The 29th Israel Conference on Mechanical Engineering. May 12-13, 2003 Haifa, Israel. Haifa: Technion - Israel Inst. Technol.**2003[B8] s. 1-8, 5 rys. bibliogr. 7 poz. Nieliniowa identyfikacja pojazdów podwodnych.
PublicationArtykuł dotyczy identyfikacji nieliniowych modeli pojazdów podwodnych o wie-lu zmiennych. Zaproponowana metoda działa w obszarze czasu rzeczywistego imoże być stosowana do nieliniowych modeli, które są liniowe w części doty-czącej nieznanego wektora parametrów. W celu poradzenia sobie z parametramizmieniającymi się w czasie, zastosowano rekursyjną wersję algorytmu identy-fikacji. Po krótkim opisie matematycznych podstaw...
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Non-Wave Variations in Temperature Caused by Sound in a Chemically Reacting Gas
PublicationA weakly nonlinear generation of non-acoustic modes in the field of sound in a gas is considered. An exotericchemical reaction of A->B type, which takes place in a gas, may be reversible or not. Two types of sound areconsidered, low-frequency and high-frequency as compared with the characteristic time of a chemical reaction.For both these cases, the governing equations of non-acoustic modes are derived and conclusions of the efficiencyof...
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Processing of acoustical data in a multimodal bank operating room surveillance system
PublicationAn automatic surveillance system capable of detecting, classifying and localizing acoustic events in a bank operating room is presented. Algorithms for detection and classification of abnormal acoustic events, such as screams or gunshots are introduced. Two types of detectors are employed to detect impulsive sounds and vocal activity. A Support Vector Machine (SVM) classifier is used to discern between the different classes of...
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Audio-visual surveillance system for application in bank operating room
PublicationAn audio-visual surveillance system able to detect, classify and to localize acoustic events in a bank operating room is presented. Algorithms for detection and classification of abnormal acoustic events, such as screams or gunshots are introduced. Two types of detectors are employed to detect impulsive sounds and vocal activity. A Support Vector Machine (SVM) classifier is used to discern between the different classes of acoustic...
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Temper bead welding of S420G2+M steel in water environment
PublicationThe article presents the idea of the use of Temper Bead Welding (TBW) technique to improve the weldability of high strength steel at underwater wet welding conditions. Wet welding method with the use of covered electrodes is described. This work shows results of metallographic examinations and hardness measurements of samples of S420G2+M steel with weld beads performed under water. It has been shown that Temper Bead Welding technique...
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Precise Bathymetry as a Step Towards Producing Bathymetric Electronic Navigational Charts for Comparative (Terrain Reference) Navigation
PublicationBathymetric Electronic Navigational Charts (bENCs) contain only bathymetry data and can be used in applications such as underwater positioning, dredging and piloting. According to International Hydrographic Organization (IHO) standard S-57, Electronic Navigational Charts (ENCs) contain depth information with pure density of depth contours. Typical depth contours encoded by Hydrographic Offices are limited to 2, 5, 10 and 20 m....
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Temper bead welding of S460N steel in wet welding conditions
PublicationWet welding is the most common method of welding in water environment. It is most often used for repairing of underwater parts of offshore structures. However, the water as a welding environment causes an increase of susceptibility of steels to cold cracking. For underwater constructions high strength low alloy (HSLA) steel are widely used. In wet welding condition a HSLA steel is characterized by high susceptibility to cold cracking....
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Monitoring of Caged Bluefin Tuna Reactions to Ship and Offshore Wind Farm Operational Noises
PublicationUnderwater noise has been identified as a relevant pollution affecting marine ecosystems in different ways. Despite the numerous studies performed over the last few decades regarding the adverse effect of underwater noise on marine life, a lack of knowledge and methodological procedures still exists, and results are often tentative or qualitative. A monitoring methodology for the behavioral response of bluefin tuna (Thunnus thynnus)...
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A double-talk detector using audio watermarking
Publicationa novel approach to double-talk detection in the acoustic echo canceler is proposed. a hidden signature is embedded into the arriving signal, using the echo-hiding method. next detection of the presence of this signature in the microphone signal is performed. the results of the signature detection may be used by the acoustic echo canceler to stop or restart the adaptation process.
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Highlighting interlanguage phoneme differences based on similarity matrices and convolutional neural network
PublicationThe goal of this research is to find a way of highlighting the acoustic differences between consonant phonemes of the Polish and Lithuanian languages. For this purpose, similarity matrices are employed based on speech acoustic parameters combined with a convolutional neural network (CNN). In the first experiment, we compare the effectiveness of the similarity matrices applied to discerning acoustic differences between consonant...
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Nonlinear properties of the Gotland Deep – Baltic Sea
PublicationThe properties of the nonlinear phenomenon in water, including sea water, have been well known for many decades. The feature of the non homogeneous distribution of the speed of sound along the depth of the sea is very interesting from the physical and technical point of view. It is important especially in the observation of underwater area by means of acoustical method ( Grelowska et al ., 2013; 2014). The observation of the underwater...
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Design of M2M Communications Interfaces in Transport Systems
PublicationIn the paper the principle of M2M communications in transport systems is presented. The concept of M2M system architecture is considered. Characteristics of M2M communications for example data transmission, monitoring and other services for transport applications are presented. The problem of communications interfaces design for M2M applications is analysed. Next, the proposal of M2M communication interface for transport applications...
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Entanglement-redistribution boxes
PublicationWe establish a framework to study the classical-communication properties of primitive local operations assisted by classical communication which realize various redistributions of entanglement, like, e.g., entanglement swapping. On the one hand, we analyze what local operations and how much classical communication are needed to perform them. On the other hand, we investigate whether and to what extent such primitives can help to...
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Acoustical images of the Gulf of Gdansk
PublicationAcoustic images of seabed are of interest to specialists in the field of marine engineering, marine navigation, marine archeology, hydrogeology, etc. New technolo gies based on use of elastic waves, predominantly acoustic waves that allow detecting complexity of geometric forms of seabed, ensure progress in studying the bathymetric structure of seafloor. Use of parametric sources of waves generated...
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Hysteresis curves and loops for harmonic and impulse perturbations in some non-equilibrium gases
PublicationEvolution of sound in a relaxing gas whose properties vary in the course of wave propagation, is studied. A relaxing medium may reveal normal acoustic properties or be acoustically active. In the first case, losses in acoustic energy lead to an increase in internal energy of a gas similarly as it happens in Newtonian fluids. In the second case, acoustic energy increases in the course of sound propagation, and the internal energy...