Rozprawy doktorskie na temat „Acoustic identification”
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Silva, Bruno Miguel Santos Antunes. "Automated acoustic identification of bat species". Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/9101.
Pełny tekst źródłaCabell, Randolph H. "The automatic identification of aerospace acoustic sources". Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/45932.
Pełny tekst źródłaThis work describes the design of an intelligent recognition system used to distinguish noise signatures of five different acoustic sources. The system uses pattern recognition techniques to identify the information obtained from a single microphone. A training phase is used in which the system learns to distinguish the sources and automatically selects features for optimal performance. Results were obtained by training the system to distinguish jet planes, propeller planes, a helicopter, train, and wind turbine from one another, then presenting similar sources to the system and recording the number of errors. These results indicate the system can successfully identify the trained sources based on acoustic information. Classification errors highlight the impact of the training sources on the system's ability to recognize different sources.
Master of Science
DeMarco, Andrea. "Acoustic approaches to gender and accent identification". Thesis, University of East Anglia, 2015. https://ueaeprints.uea.ac.uk/53443/.
Pełny tekst źródłaFox, Elizabeth J. S. "Call-independent identification in birds". University of Western Australia. School of Animal Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0218.
Pełny tekst źródłaSchuler, Leo Pius. "Wireless identification and sensing using surface acoustic wave devices". Thesis, University of Canterbury. Electrical Engineering, 2003. http://hdl.handle.net/10092/1081.
Pełny tekst źródłaSchuler, Leo P. "Wireless identification and sensing using surface acoustic wave devices". Thesis, University of Canterbury. Engineering, 2003. http://hdl.handle.net/10092/8565.
Pełny tekst źródłaHedayetullah, Amin Mohammad. "Optimization of identification of particle impacts using acoustic emission". Thesis, Robert Gordon University, 2018. http://hdl.handle.net/10059/3116.
Pełny tekst źródłaSchofield, James. "Real-time acoustic identification of invasive wood-boring beetles". Thesis, University of York, 2011. http://etheses.whiterose.ac.uk/1978/.
Pełny tekst źródłaMoat, Trevor P. B. M. "Orthogonal adaptive digital filters with applications to acoustic system identification". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0025/MQ27022.pdf.
Pełny tekst źródłaGaubitch, Nikolay Dian. "Blind identification of acoustic systems and enhancement of reverberant speech". Thesis, Imperial College London, 2007. http://hdl.handle.net/10044/1/12025.
Pełny tekst źródłaRadcliffe, Stewart Alexander. "Acoustical identification of the characteristics of ocean fronts". Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245396.
Pełny tekst źródłaKenny, Thomas Donald. "Identification of High-Velocity Pseudo-surface Acoustic Wave Substrate Orientations and Modeling of Surface Acoustic Wave Structures". Fogler Library, University of Maine, 2011. http://www.library.umaine.edu/theses/pdf/KennyT2011.pdf.
Pełny tekst źródłaYang, Xi. "Discriminative acoustic and sequence models for GMM based automatic language identification /". View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECED%202007%20YANG.
Pełny tekst źródłaHu, Mathieu. "Cross-relation based blind identification of acoustic SIMO systems and applications". Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/52430.
Pełny tekst źródłaFacciotto, Nicolò. "Source differentiation and identification of acoustic emission signals by time-frequency analysis". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Znajdź pełny tekst źródłaBoukis, Christos. "Adaptive digital signal processing structures and identification algorithms for acoustic feedback control". Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407894.
Pełny tekst źródłaGarudadri, Harinath. "Identification of invariant acoustic cues in stop consonants using the Wigner distribution". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/28786.
Pełny tekst źródłaApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Lauritzen, Michael Kenneth. "Acoustic Mediation of Vocalized Emotion Identification: Do Decoders Identify Emotions Idiographically or Nomothetically?" Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3352.pdf.
Pełny tekst źródłaRogers, Daniel James. "Intraspecific variation in the acoustic signals of birds and one species of frog : implications for the acoustic identification of individuals". Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phr7251.pdf.
Pełny tekst źródłaIrons-Brown, Shunda R. "Identification of post-synaptic receptors mediating eighth nerve function". free online free to MU campus, others may purchase, 2002. http://wwwlib.umi.com/cr/mo/preview?3074410.
Pełny tekst źródłaPaxton, Scott. "System Identification and Optimization Methodologies for Active Structural Acoustic Control of Aircraft Cabin Noise". Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36876.
Pełny tekst źródłaThere has been much recent research on the control of complex sound fields in enclosed vibrating structures via active control techniques. Active Structural Acoustic Control (ASAC) has shown much promise for reducing interior cabin noise in aircraft by applying control forces directly to the fuselage structure. Optimal positioning of force actuators for ASAC presents a challenging problem however, because a detailed knowledge of the structural-acoustic coupling in the fuselage is required.
This work is concerned with the development of a novel experimental technique for examining the forced harmonic vibrations of an aircraft fuselage and isolating the acoustically well-coupled motions that cause significant interior noise. The developed system identification technique is itself based upon an active control system, which is used to approximate the disturbance noise field in the cabin and apply an inverse excitation to the fuselage structure. The resulting shell vibrations are recorded and used to optimally locate piezoelectric (PZT) actuators on the fuselage for ASAC testing.
Experiments for this project made use of a Cessna Citation III aircraft fuselage test rig.
Tests were performed at three harmonic disturbance frequencies, including an acoustic
resonance, an off-resonance, and a structural resonance case. In all cases, the new system
identification technique successfully isolated a simplified, low-magnitude vibration pattern
from the total structural response caused by a force disturbance applied at the fuselage's
rear engine mount. These measured well-coupled vibration components were used for
positioning candidate piezoelectric actuators on the fuselage shell. A genetic algorithm
search provided an optimal subset of actuators for use in an ASAC system. ASAC tests
confirmed the importance of actuator location, as the optimal sets outperformed alternate
groupings in all test cases. In addition, significant global control was achieved, with sound
level reductions observed throughout the passenger cabin with virtually no control
spillover.
Master of Science
Sasidharan, Nair Unnikrishnan. "Jet noise source localization and identification". The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1482412964456451.
Pełny tekst źródłaFrangakis, Stephanie. "Material parameter identification of acoustic polymeric foams via theoretical modeling and experimental measurements". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 0.41 Mb., 46 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1430780.
Pełny tekst źródłaChesnais, Corentin. "Holographie vibratoire : Identification et séparation de champs vibratoires". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI127/document.
Pełny tekst źródłaThe source field reconstruction aims at identifying the excitation field measuring the response of the system. In Near-field Acoustic Holography, the response of the system (the radiated acoustic pressure) is measured on a hologram using a microphones array and the source field (the acoustic velocity field) is reconstructed with a back-propagation technique performed in the wave number domain. The objective of the present works is to use such a technique to reconstruct displacement field on the whole surface of a plate by measuring vibrations on a one-dimensional holograms. This task is much more difficult in the vibratory domain because of the complexity of the equation of motion of the structure. The method presented here and called "Structural Holography" is particularly interesting when a direct measurement of the velocity field is not possible. Moreover, Structural Holography decreases the number of measurements required to reconstruct the displacement field of the entire plate. This method permits to separate the sources in the case of multi-sources excitations by considering them as direct or back waves. It’s possible to compute the structural intensity of one particular source without the contributions of others sources. The aim of this PHD is to present the principles of Structural Holography, its limits, its applications and illustrate them with examples of infinite plate, supported plate and on experimental results
Kostrzewa, Krzysztof [Verfasser], i Manfred [Akademischer Betreuer] Aigner. "Advanced computational methods in identification of thermo-acoustic systems / Krzysztof Kostrzewa. Betreuer: Manfred Aigner". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2011. http://d-nb.info/1018421009/34.
Pełny tekst źródłaUumati, Martha. "Acoustic investigations on bearded goby and jellyfish in the northern Benguela ecosystem". Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/4469.
Pełny tekst źródłaFarren, Maureen A. "Some experiments with underwater acoustic returns from cylinders relative to object identification for AUV operation/". Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23398.
Pełny tekst źródłaUnderwater Vehicles, Sonar Sound Analyzers, Underwater Navigation, Acoustics, Anechoic Chambers, Cylindrical Bodies, Data Storage Systems, Delay, Electroacoustic Transducers, Estimates, Experimental Data, Geometric Forms, Identification, Images, Position Location, Propagation, Sonar, Surface Properties, Target Strength, Theses, Time Intervals, Underwater, Underwater Equipment
Abdou, Wael Saber Soliman. "Identification of acoustic emission sources in machinery : application to injection/combustion processes in diesel engines". Thesis, Heriot-Watt University, 2015. http://hdl.handle.net/10399/2979.
Pełny tekst źródłaCuneyitoglu, Ozkul Mine. "Acoustic Perception Through The Ground Interaction Of Compliant Legs Of A Hexapod Robot". Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614028/index.pdf.
Pełny tekst źródłaMorrison, Archie Todd. "System identification and state reconstruction for autonomous navigation of an underwater vehicle in an acoustic net". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/37999.
Pełny tekst źródłaGRSN 683373
Includes bibliographical references (leaves 202-205).
by Archie Todd Morrison, III
Ocean.E.
Nagl, Michael Martin. "Identification of the mechanism of oxide scale fracture, and its correlation with strain using acoustic emission". Thesis, University of South Wales, 1992. https://pure.southwales.ac.uk/en/studentthesis/identification-of-the-mechanism-of-oxide-scale-fracture-and-its-correlation-with-strain-using-acoustic-emission(60f7dec2-bf42-4f44-86f7-b216a1adc662).html.
Pełny tekst źródłaMenon, Amrita Madhukumar. "The use of automated acoustic identification software for bat surveys in the neotropics : Gaps and opportunities". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/173540.
Pełny tekst źródłaBat populations are known to be affected by anthropogenic activities because bats are an extremely diverse group occupying almost all available niches in terrestrial environment. Hence, bats are considered bioindicators to monitor changes in the environment, but their value as such also depends on the ease to monitor and detect demographic trends in their populations. The long term interest of researchers in the acoustic of bats results from the fact that it is a non-invasive, time-efficient methods to monitor spatiotemporal patterns of bat diversity and activity.The analysis of sounds emitted by organisms has been considered useful to gain insight into species-specific biotic and abiotic interactions, which can further be applied to conservation. Besides manual identifications of bat calls, a number of automated species identification programs using regional call classfiers have been introduced into the market as an efficient tool in monitoring of bat populations. Most of these programs have not been validated using field data. This study evaluates the reliability of two automated softwares, SonoChiro and Kaleidoscope Pro, in comparison to manual identifications of field data collected from the Neotropical region. There was low agreement between the two automated methods at the species level, fair agreement at the genus level and moderate agreement at the family level. There was also a significant difference between the proportion of correctly identified calls of the two-automated software at the species level identifications. Major challenges for using automated identification software include the need for comprehensive call libraries of the regions under scope; major opportunities, on the other hand, include the widespread possibility to monitor spatiotemporal patterns of bat activity. Overall, there are serious gaps that preclude a widespread application of automated programs in ecological and conservation studies of bats, but there is a potential for improvement. Considering the limitations of the automated programs, a framework for application in ecological and conservation studies is discussed.
Goodwin, Katy Rebecca. "Bat Population Monitoring in National Parks of The Great Lakes Region and Evaluation of Bat Acoustic Analysis Software". Thesis, North Dakota State University, 2019. https://hdl.handle.net/10365/31570.
Pełny tekst źródłaJanos, Gregg A. "Utilizing Acoustic Methods to Identify Bat Species, and to Assess Their Habitat Use and Perception of Owls". Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1363428258.
Pełny tekst źródłaMeesala, Vamsi Chandra. "Nonlinear Effects in Contactless Ultrasound Energy Transfer Systems". Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/101752.
Pełny tekst źródłaDoctor of Philosophy
Advancements in electronics that underpinned the development of low power sensors and devices have transformed many fields. For instance, it has led to the innovation of implanted medical devices (IMDs) such as pacemakers and neurostimulators that perform life-saving functions. They also find applications in condition monitoring and wireless sensing in nuclear power plants, space stations, automobiles and aircraft engines, where the sensors are enclosed within sealed metal containers, vacuum/pressure vessels or located in a position isolated from the operator by metal walls. In all these applications, it is desired to communicate with and recharge the sensors wirelessly. Such a mechanism can eliminate the need for invasive and expensive surgeries to replace batteries of IMDs and preserve the structural integrity of metal containers by eliminating the need for feed through wires. It has been shown that ultrasound acoustic energy transfer (UAET) outperforms conventional wireless power transfer techniques. However, existing models are based on several assumptions that limit their potential and do not account for effects that become dominant when a higher output power is desired. In this dissertation, we present experimentally validated numerical and theoretical investigations to fill those knowledge gaps. We also provide crucial design recommendations based on our findings for the efficient implementation of UAET technology.
LEE, JOON-HYUN. "DEVELOPMENT OF NEW TECHNIQUE FOR DAMPING IDENTIFICATION AND SOUND TRANSMISSION ANALYSIS OF VARIOUS STRUCTURES". University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin985028187.
Pełny tekst źródłaBousabaa, Sofiane. "Acoustic Green’s Function Estimation using Numerical Simulations and Application to Extern Aeroacoustic Beamforming". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS228.
Pełny tekst źródłaAcoustic imaging techniques aims at characterizing the different acoustic sources of noise on an aircraft using microphone array measurements. Those techniques require the knowledge of the acoustic Green’s function of the medium. Unfortunately, this function is known only for cases of relatively simple complexity and the use of approximate Green’s function can lead to errors in the identification of the sources. The main aim of this thesis is to set up a numerical method for the estimation of the Green’s function for aeroacoustic imaging applications. The method must have a minimal computational cost and provide a sufficiently accurate estimation to be used on realistic industrial configurations. The proposed methodology takes advantage of the sparsity of the Green’s functions in the time-domain. This results in a system identification problem and sparsity-based regression algorithms can be used to solve it. First, the method is validated on complex 3D numerical test cases typical of those encountered in the industry. For configurations involving a high number of focus points, the reverse-flow reciprocity simplifies significantly the Green’s function estimation problem. The methodology is finally applied on high lift 2D wing data placed in the ONERA CEPRA19 open section anechoic wind tunnel justifying the applicability of the method on realistic industrial configurations
Cousson, Rémi. "Identification de sources acoustiques au passage d'un véhicule routier par imagerie acoustique parcimonieuse dans le domaine temporel". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI106/document.
Pełny tekst źródłaThe study detailed in this manuscript is part of the effort to characterize the noise emission from road vehicles. We wish to identify the noise sources of a moving vehicle, when driven on a roadway in real-world conditions, with roadside acoustic measurements. The current acoustic imaging methods do not provide sufficient performance on road vehicles. A state of the art led to the selection of an existing method, MSA-PSF, which consists in deconvolving signals from mobile sources in the frequency domain under certain assumptions, and was originally developed for aeroacoustics. This method is adapted here to the context of road vehicles. Then, an original approach is proposed in order to tackle the specific constraints of this context: CLEANT. This is an iterative method, performed in time domain with a wideband approach, which takes into account the effect of sources motion and includes two parameters designed to refine the result: the loop factor and the stopping criterium. A further version of the algorithm, including a frequency filter, is also proposed and shows significant improvement in identifying secondary sources in some particular cases. An interesting point of CLEANT is the availability of the sources reconstructed time signals, which enables other types of analysis, especially the use of the coherence with signals from on-board measurements in order to separate the contributions of uncorrelated sources. MSA-PSF and CLEANT are evaluated with numerical simulations and a set of indicators to measure their source localization and quantification performance. They are then tested in a controlled laboratory conditions experiment, using a moving source. This experiment represents a first application of the methods to a practical case, involving a linear motion, two simultaneous sources and different kinds of signals (tone and wideband). They are finally compared to the classical approach of moving source beamforming, within the frame of an experiment on a road vehicle, in real-world conditions. The original approach CLEANT yields very encouraging results, and is a clear improvement from the conventional beamforming, especially at low frequency for the tested cases. Applying it to a road vehicle in real-world conditions highlights a potentially troublesome behavior of the method, and the solution brought by CLEANT's frequency filtered version, or by adapting its various parameters. The coherence with reference signals to discriminate the physical origins of the sources is also tested and underlines the role of the short duration of the signals related to the sources passing-by context
Cellier, Antony Hermann Guy. "Detection and Identification of Instability and Blow-off/Flashback Precursors in Aeronautical Engines using Deep Learning techniques". Thesis, KTH, Kraft- och värmeteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-272079.
Pełny tekst źródłaUtvecklingen av injektionsprocesser mot mer bränsleeffektiva och mindre förorenande förbränningssystem, tenderar att göra dem mer benägna att utsättas för kritiska händelser som Thermo-Acoustic Instabilities, Blow-Off och Flash-Back. Dessutom diskuterar flygmotorkonstruktörer möjligheten att använda Dihydrogen som sekundärt eller som huvudbränsle. Det modifierar drastiskt systemets stabilitet och det väcker frågan hur man kan använda det effektivt. Att kunna förutsäga kritiska fenomen blir en nödvändighet för att använda ett system utan att behöva att på förhand testa varje konfiguration och utan att reducera användarens säkerhet. Baserat på Deep-Learning-tekniker och Speech-Recognition-tekniker, presenterar följande studie stegen för att utveckla ett verktyg som kan upptäcka och översätta föregångare till instabilitet hos en swirled flygmotorerinsprutningspump som är innesluten i en förbränningskammare. De lovande resultaten leder till idéer om hur man kan anpassa det här verktyg till ett system i verklig storlek.
Grialou, Matthieu. "Vibro-acoustics substructuring : Combining simulations and experimental identification of subdomains for low frequency vehicle acoustics". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI109/document.
Pełny tekst źródłaExhaust noise has a significant impact on acoustic comfort and the sound identity of a vehicle brand. The present study focuses on the: “Description and quantification of the sound transmission from the exhaust outlet into the interior of a vehicle”. Physically the noise propagation from the exhaust pipe to the cabin consists of three steps: The sound waves propagate through the air from the exhaust outlet to the external skin of the vehicle (1); the external skin vibrates and transmits its vibration to the internal skin (2); the internal skin radiates sound in the passengers’ cabin (3). The Patch Transfer Functions method, which is based on the framework of dynamic substructuring, allows for the consideration of this complex problem as simpler subproblems that consist of subsystem interactions. Yet the application of the method to a full vehicle requires addressing the problem: “Characterization of Patch Transfer Functions of a subsystem by means of measurement on a coupled system”. This dissertation presents an original inverse method for the measurement of Patch Transfer Functions. In industrial structures, this in-situ characterization is generally the only possible measurement method. Yet, due to the ill posed nature of the problem, the inversion process is difficult. An original regularization method is proposed. The method is tested through numerical simulations, and is validated with an experimental setup
Le, Magueresse Thibaut. "Approche unifiée multidimensionnelle du problème d'identification acoustique inverse". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI010.
Pełny tekst źródłaExperimental characterization of acoustic sources is one of the essential steps for reducing noise produced by industrial machinery. The aim of the thesis is to develop a complete procedure to localize and quantify both stationary and non-stationary sound sources radiating on a surface mesh by the back-propagation of a pressure field measured by a microphone array. The inverse problem is difficult to solve because it is generally ill-conditioned and subject to many sources of error. In this context, it is crucial to rely on a realistic description of the direct sound propagation model. In the frequency domain, the equivalent source method has been adapted to the acoustic imaging problem in order to estimate the transfer functions between the source and the antenna, taking into account the wave scattering. In the time domain, the propagation is modeled as a convolution product between the source and an impulse response described in the time-wavenumber domain. It seemed appropriate to use a Bayesian approach to use all the available knowledge about sources to solve this problem. A priori information available about the acoustic sources have been equated and it has been shown that taking into account their spatial sparsity or their omnidirectional radiation could significantly improve the results. In the assumptions made, the inverse problem solution is written in the regularized Tikhonov form. The regularization parameter has been estimated by an empirical Bayesian approach. Its superiority over methods commonly used in the literature has been demonstrated through numerical and experimental studies. In the presence of high variability of the signal to noise ratio over time, it has been shown that it is necessary to update its value to obtain a satisfactory solution. Finally, the introduction of a missing variable to the problem reflecting the partial ignorance of the propagation model could improve, under certain conditions, the estimation of the complex amplitude of the sources in the presence of model errors. The proposed developments have been applied to the estimation of the sound power emitted by an automotive power train using the Bayesian focusing method in the framework of the Ecobex project. The cyclo-stationary acoustic field generated by a fan motor was finally analyzed by the real-time near-field acoustic holography method
Young, Kathryn. "Identification and Estimation of Sensitive Life History Parameters for Cetaceans in Response to Acoustic Disturbances with Implications for Conservation". NSUWorks, 2008. http://nsuworks.nova.edu/occ_stuetd/238.
Pełny tekst źródłaFaber, Benjamin Mahonri. "Active Minimization of Acoustic Energy Density in a Mock Tractor Cab". BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/129.
Pełny tekst źródłaDemontis, Hugo. "Identification de sources acoustiques complexes en milieu réverbérant par grands réseaux de microphones". Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS196.
Pełny tekst źródłaKnowing the directivity pattern of an acoustic source is useful in many applications in acoustics. To experimentally estimate the spatial signature, it is common to deploy microphones partially or totally surrounding the source. The acoustic radiation is then captured in all possible directions. In this thesis, we discuss the development of a large-scale 3D microphone array. This array, named "MODO" ("Les Murs Ont Des Oreilles", or, "The Walls Have Ears"), is comprised of 1024 digital MEMS microphones, flush mounted on the walls and the ceiling of a typical shoe-box room. In order to localize the sources and identify their directivity pattern, we solve the associated inverse problem under block-sparsity constraints. The chosen method exploits the small number of sources inside the room, allowing a sparse representation of the measured sound field. We use the spherical harmonics formalism to efficiently describe the directivity of the sources and their individual contributions to the radiation pattern. The acoustic path is modelled via integration of room transfer functions, synthesized with the mirror microphone method. We validated the proposed characterization method \textit{in situ} by comparison with known directivity patterns, calibrated using a high order spherical microphone array in controlled conditions
Burnett, Stephen C. "Individual variation in the echolocation calls of Big Brown Bats (Eptesicus fuscus) and their potential for acoustic identification and censusing /". The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486394475981357.
Pełny tekst źródłaUdeigwe, Lawrence C. "Identification of objects in an acoustic waveguide numerical results and an introduction to an alternate approach via the method of images /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 0.51 Mb., 34 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:.
Pełny tekst źródłaBuot, de l’Épine Yorick. "Identification de l’impédance d’un traitement en présence d’un écoulement". Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2369/document.
Pełny tekst źródłaLocally reactive acoustic liners such as honeycomb structures with perforated panels can be modeled with a surface impedance in standard numerical models. However, the characterization of this impedance is not always straightforward. Empirical models or standing wave tube measurements are generally used to get the behavior of these acoustic treatments. Unfortunately, these methods provide only an evaluation of the impedance under specific conditions. Moreover, the conditions of use can change significantly the acoustic liners behavior as grazing flow conditions or oblique incident waves. A characterization of locally reactive acoustic liners is presented here. Starting from a set of parameters and represents a surface impedance using empirical model, an inverse method based on Bayesian approach is used to return the surface impedance taking in consideration the real conditions of use. A rectangular duct treated by a liner on its upper face is considered and these conditions are similar to the experiment present at the Université de Technologie de Compiègne. This inverse method requires a direct model to predict the pressure at some microphone positions with any surface impedance. The model used in the following is based on the Mode-Matching method. From the direct analytical model, the Bayes'rule is then used to get the posterior probability density function of the estimated impedance. An Evolutionary Monte Carlo by Markov chain (EMCMC) method is used to sample this posterior probability density. This method provides not only the best set of parameters but also some statistical information for each parameter
Harris, Elizabeth A. "Detection and Identification of Marine Mammals in Passive Acoustic Recordings from SCORE using a Visual Processing Approach Established for HARP Data". Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/7354.
Pełny tekst źródłaGrisel, Yann. "Localisation de défauts et applications pour les milieux inhomogènes en propagation d'ondes acoustiquesDefects localization and applications to inhomogeneous media in acoustic scattering". Phd thesis, Université Paul Sabatier - Toulouse III, 2011. http://tel.archives-ouvertes.fr/tel-00675217.
Pełny tekst źródłaNocera, Tomas. "Assessing the Long-term Impacts of White-nose Syndrome on Bat Communities Using Acoustic Surveys at Fort Drum Military Installation". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/95937.
Pełny tekst źródłaMS