Log in

Relevant bibliographies by topics / Acoustic modelling / Dissertations / Theses

To see the other types of publications on this topic, follow the link: Acoustic modelling.

Dissertations / Theses on the topic 'Acoustic modelling'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 July 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Acoustic modelling.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Ribichini, Remo. "Modelling of electromagnetic acoustic transducers." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9010.

Full text

Abstract:

At present, the dominant technology for transducers in the field of Ultrasonic Non-Destructive Testing is piezoelectric. However, some industrially important applications, like the inspection of components operating at high temperature or while in motion, are difficult tasks for standard piezoelectric probes since mechanical contact is required. In these cases, contactless NDT techniques can be an attractive alternative. Among the available options, Electromagnetic Acoustic Transducers (EMATs) can generate and detect ultrasonic waves without the need for a physical contact between the probe an

APA, Harvard, Vancouver, ISO, and other styles

2

Ramanathan, Sathish Kumar. "Linear Acoustic Modelling and Testing of Exhaust Mufflers." Thesis, KTH, Aeronautical and Vehicle Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4340.

Full text

Abstract:

<p>Intake and Exhaust system noise makes a huge contribution to the interior and exterior noise of automobiles. There are a number of linear acoustic tools developed by institutions and industries to predict the acoustic properties of intake and exhaust systems. The present project discusses and validates, through measurements, the proper modelling of these systems using BOOST-SID and discusses the ideas to properly convert a geometrical model of an exhaust muffler to an acoustic model. The various elements and their properties are also discussed.</p><p>When it comes to Acoustic properties the

APA, Harvard, Vancouver, ISO, and other styles

3

Hurrell, Andrew M. "Finite difference modelling of acoustic propagation and its applications in underwater acoustics." Thesis, University of Bath, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250842.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Ajaz, Mahnoor. "Finite Difference Time Domain Modelling of Ultrasonic Parametric Arrays in Two-Dimensional Spaces." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1619109761801613.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Laurinčiukaitė, Sigita. "Acoustic modelling of Lithuanian speech recognition." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080626_121551-77545.

Full text

Abstract:

This paper is devoted to an acoustic modelling of Lithuanian speech recognition. Word-, syllable-, contextual syllable-, phoneme- and contextual phoneme-based speech recognition was investigated. Investigations were performed for isolated words and continuous speech. The most popular sub-word units in Lithuanian speech recognition are phonemes and contextual phonemes, and research on other sub-word units is omitted. This paper aims to compare capacity of linguistic sub-word units to model speech and to demonstrate that investigation of sub-word units suggest using alternative sub-word units to

APA, Harvard, Vancouver, ISO, and other styles

6

Wong, Lawdy Siu Shan. "Auditorium acoustic modelling on chaotic realisation." Thesis, Oxford Brookes University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394625.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Oxnard, Stephen. "Efficient hybrid virtual room acoustic modelling." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/17459/.

Full text

Abstract:

This thesis investigates approaches to virtual room acoustic modelling and auralisation in order to a develop hybrid modelling solution that is capable of efficient and accurate simulation of enclosed sound propagation. Emphasis is placed on the advantages and disadvantages of state of the art numerical and geometric acoustic modelling methods. Numerical methods have been shown to preserve important sound wave characteristics such as diffraction and room modes, and are considered more accurate for low frequency acoustic modelling than geometric techniques which fail to preserve such wave effec

APA, Harvard, Vancouver, ISO, and other styles

8

Hunter, Alan Joseph. "Underwater Acoustic Modelling for Synthetic Aperture Sonar." Thesis, University of Canterbury. Electrical and Computer Engineering, 2006. http://hdl.handle.net/10092/1117.

Full text

Abstract:

Underwater acoustic modelling is an important aspect of Synthetic Aperture Sonar (SAS) system design and algorithm development. Sea-trials are an expensive and time-consuming exercise and simulations provide an efficient and economic alternative. However, there are few simulators (in the open literature) that can efficiently provide realistic SAS data for large, complicated scenes. Conventional side-scan sonar simulators are not suitable for SAS data simulation. These simulators utilise narrow-beam and narrow-band approximations; typical SAS systems are wide-beam and wide-band and these app

APA, Harvard, Vancouver, ISO, and other styles

9

Shannon, Sean Matthew. "Probabilistic acoustic modelling for parametric speech synthesis." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708415.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Zhang, Ning. "The computational modelling of electromagnetic acoustic imaging." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:2c4c9946-b90c-43a3-9039-1c7df2dcd976.

Full text

Abstract:

The Electromagnetic Acoustic (EMA) technique is a novel multi-modal technique for medical imaging. It is sensitive, in principle, to contrast in mechanical properties and electrical properties and has potential in a number of applications such as breast tumour detection where there will be contrast between diseased and healthy tissue and high intensity focused ultrasound monitoring, where there will be contrast when tissue is ablated. A complete computational model for the EMA imaging is developed. The model considers the linear or nonlinear propagation of ultrasound in soft tissue, the dynami

APA, Harvard, Vancouver, ISO, and other styles

11

Jackson, Edward James. "Modelling and monitoring nonlinear acoustic phenomena in high-intensity focused ultrasound therapy." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:cea762cf-8a12-4265-b1b1-a15214c58ac3.

Full text

Abstract:

High intensity focused ultrasound (HIFU) provides a wide range of noninvasive therapies ranging from drug delivery to the destruction of kidney stones. In particular, thermal ablation by HIFU presents an effective noninvasive method for the treatment of deep seated solid tumours. HIFUâs further uptake is limited by a need for improved treatment planning and monitoring. Two nonlinear acoustic phenomena that play key roles in HIFU treatment: finite amplitude effects that lead to the generation of harmonics and steepening of wavefronts, and acoustic cavitation. The former must be taken into car

APA, Harvard, Vancouver, ISO, and other styles

12

Svensson, Elin. "Physical modelling of acoustic shallow-water communication channels." Doctoral thesis, Stockholm : Farkost och flyg, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4572.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Leggetter, Christopher John. "Improved acoustic modelling for HMMs using linear transformations." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361709.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Thomas, Sadiq. "Comprehensive finite element modelling of electromagnetic acoustic transducers." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509874.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Willison, Peter A. "Transmission line matrix modelling of underwater acoustic propagation." Thesis, University of Essex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334426.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Orme, E. A. "TLM applied to the modelling of underwater acoustic scattering." Thesis, University of Nottingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371287.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Kirby, Raymond. "The acoustic modelling of dissipative elements in automotive exhausts." Thesis, Online version, 1996. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.361493.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Hazzard, James F. "Numerical modelling of acoustic emissions and dynamic rock behaviour." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265036.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Simmons, Stephen Michael. "Non-linear modelling of the acoustic response of bubbles." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364761.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Leonard, Gordon. "Acoustic modelling of bat pinnae utilising the TLM method." Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/20204.

Full text

Abstract:

This thesis describes the numerical modelling of bioacoustic structures, the focus being the outer ear or pinnae of the Rufous Horseshoe bat (Rhinolophus rouxii). There have been several novel developments derived from this work including: • A method of calculating directionality based on the sphere with a distribution of measuring points such that each lies in an equal area segment. • Performance estimation of the pinna by considering the directionality of an equivalent radiating aperture. • A simple synthetic geometry that appears to give similar performance to a bat pinna. The outcome of ap

APA, Harvard, Vancouver, ISO, and other styles

21

Gonçalves, Da Silva Pinto Wagner José. "Modelling airframe noise : from aerodynamic topology to acoustic efficiency." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2289.

Full text

Abstract:

L’influence de la forme de cylindres longs sur leur rayonnement acoustique en écoulement est étudiée. Des simulations bidimensionnelles (2D) sont réalisées à bas nombre de Reynolds (Re=20-200), à l’aide du code de calcul direct (DNS) incompressible incompact3D au moyen d’une méthode de frontière immergée (IBM). Une formule dérivée de l’équation de Curle pour un cylindre compact permet la quantification de l’émission acoustique en 2D. En soufflerie anéchoïque, la signature acoustique d’une trentaine de géométries est mesurée, Re=4,000-53,000 ; l’anémométrie par fil chaud est utilisée pour la de

APA, Harvard, Vancouver, ISO, and other styles

22

Hörlin, Nils-Erik. "Hierarchical finite element modelling of Biot's equations for vibro-acoustic modelling of layered poroelastic media." Doctoral thesis, KTH, Farkost- och flygteknik, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-95.

Full text

Abstract:

This thesis concerns three-dimensional finite element modelling of Biot's equations for elasto-acoustic modelling of wave propagation in layered media including porous elastic materials. The concept of hierarchical (p-version) finite elements are combined with various weak forms of Biot's equations. Computationally efficient methods providing accurate solutions of sound propagation in layered porous media are discussed. The research falls within the areas linear acoustics and numerical acoustics. Important applications of the developed methods may be found within vehicle interior acoustics, e.

APA, Harvard, Vancouver, ISO, and other styles

23

Hörlin, Nils-Erik. "Hierarchical finite element modelling of Biot's equations for vibro-acoustic modelling of layered poroelastic media /." Stockholm, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-95.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Campos, Antonio Guilherme Rocha. "Three-dimensional digital waveguide mesh modelling for room acoustic simulation." Thesis, University of York, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423754.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Shen, Yijun. "Modelling the electro-acoustic characteristics of flow-through ultrasonic separators." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/47551/.

Full text

Abstract:

A flow-through ultrasonic separator is a novel type of separation device concentrating and separating suspended micro-particles from within a liquid in a standing ultrasonic field. It can accomplish a fast, sharp, efficient and controllable separation of micro-particles in a liquid suspension. The thesis focuses on modelling the electro-acoustic characteristics of flow-through ultrasonic separators with a special emphasis on analysing and designing the MEMS micromachined ultrasonic filter in an EPSRC and DSTL funded project. Based on the model results, a micromachined ultrasonic filter is desi

APA, Harvard, Vancouver, ISO, and other styles

26

Moss, Scott. "Modelling and experimental validation of the acoustic electric feedthrough technique." Fishermans Bend, Victoria : Defence Science and Technology Organisation, 2008. http://hdl.handle.net/1947/9738.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Wood, Michael Alan. "Modelling and prediction of acoustic disturbances from off-shore piling." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/412708/.

Full text

Abstract:

This work presents details of a number of approaches used to elucidate the noise generating mechanisms involved in pile-driving through multiple modelling techniques. Principally, the work is divided into four sections: fluid-sediment analysis, recording analysis, elastic-sediment analysis, and wave equation analysis of piles. In the fluid-sediment analysis section, finite-element models were used to investigate the effect of varying the hammer cushion compliance on the radiated noise of a pile in situ. The compliance of the cushion affected the frequency response of the forcing function with

APA, Harvard, Vancouver, ISO, and other styles

28

Koessler, Matthew Walter. "Modelling of underwater acoustic propagation over elastic, range-dependent seabeds." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/2022.

Full text

Abstract:

Research was conducted on the development of a numerical algorithm that can accurately model range dependent acoustic propagation over layered calcarenite seabeds that are typical around Australia. A seismoacoustic adiabatic normal mode algorithm was developed and tested against an existing seismoacoustic parabolic equation code, and also compared to measured data. Both methods yielded accurate results but the adiabatic mode method proved to be much faster than the parabolic equation method.

APA, Harvard, Vancouver, ISO, and other styles

29

Yang, Haofan. "Reputation modelling in citizen science for environmental acoustic data analysis." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/54657/1/Haofan_Yang_Thesis.pdf.

Full text

Abstract:

Citizen Science projects are initiatives in which members of the general public participate in scientific research projects and perform or manage research-related tasks such as data collection and/or data annotation. Citizen Science is technologically possible and scientifically significant. However, as the gathered information is from the crowd, the data quality is always hard to manage. There are many ways to manage data quality, and reputation management is one of the common approaches. In recent year, many research teams have deployed many audio or image sensors in natural environment

APA, Harvard, Vancouver, ISO, and other styles

30

Forsyth, Simon Andrew. "Modelling of ultrasonic transduction and measurement using finite elements." Thesis, Nottingham Trent University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312311.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Ericsdotter, Christine. "Articulatory-Acoustic Relationships in Swedish Vowel Sounds." Doctoral thesis, Stockholm : Department of Linguistics, Stockholm University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-699.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Mosharrof, Mohammad Sazzad. "Study and modelling of lightweight floor structure regarding its acoustic properties." Licentiate thesis, Luleå tekniska universitet, Drift, underhåll och akustik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17520.

Full text

Abstract:

Lightweight floor structure is widely used in building industries and to have better sound insulation builders come up with different ways of construction. Depending on the construction the floor structure could either be coupled (floor and ceiling coupled by beams) or decoupled (no mechanical connection between floor and ceiling). Although there are many models on coupled structure but for decoupled structure the number is not too many. Keeping that in mind the present thesis talks about lightweight floors: the construction, properties, behaviour etc with a focus on developing a model for dec

APA, Harvard, Vancouver, ISO, and other styles

33

Noreland, Daniel. "Numerical Techniques for Acoustic Modelling and Design of Brass Wind Instruments." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3507.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Patterson, Richard Sven. "Acoustic modelling of near borehole anolmalies via the generalised radon transform." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/59049.

Full text

Abstract:

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1992.<br>Includes bibliographical references (leaves 89-91).<br>by Richard Sven Patterson.<br>M.S.

APA, Harvard, Vancouver, ISO, and other styles

35

Kao, David. "The vibro-acoustic modelling and analysis of damage mechanisms in paper." Thesis, University of Greenwich, 2006. http://gala.gre.ac.uk/6205/.

Full text

Abstract:

This thesis investigates the use of the acoustic emission (AE) monitoring technique for use in identifying the damage mechanisms present in paper associated with its production process. The microscopic structure of paper consists of a random mesh of paper fibres connected by hydrogen bonds. This implies the existence of the two damage mechanisms of interest, the failure of a fibre/fibre bond and the failure of a fibre. The majority of this work focuses on the development of a novel hybrid mathematical model which couples the mechanics of the mass/spring model to the acoustic wave propagation m

APA, Harvard, Vancouver, ISO, and other styles

36

van, Mourik J. "Higher-order finite difference time domain algorithms for room acoustic modelling." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/15661/.

Full text

Abstract:

The acoustic qualities of indoor spaces are fundamental to the intelligibility of speech, the quality of musical performances, and perceived noise levels. Computationally heavy wave-based acoustic modelling algorithms have gained momentum in the field of room acoustic modelling, as ever-increasing computational power makes their use more feasible. Most notably the Finite Difference Time Domain (FDTD) method is often employed for rendering the low- and mid-frequency part of room impulse responses (RIRs). However, this algorithm has known disadvantages, most prominently dispersion error, which r

APA, Harvard, Vancouver, ISO, and other styles

37

Medeiros, Augusto Amador. "On the modelling and characterization of acoustic liners under grazing flow." reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/136463.

Full text

Abstract:

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Mecânica, Florianópolis, 2015.<br>Made available in DSpace on 2015-11-17T03:06:05Z (GMT). No. of bitstreams: 1 335896.pdf: 3607600 bytes, checksum: eb35bf98ba72f6228bbd3656f6a1aacd (MD5) Previous issue date: 2015<br>A determinação da impedância acústica de liners utilizados em motores turbofan de aeronaves comerciais é um ponto de interesse da comunidade científica há várias décadas, especialmente na presença de escoamentos tangenciais, condição similar à de operação.

APA, Harvard, Vancouver, ISO, and other styles

38

Christen, Jean-Loup. "Acoustic transmission through composite shells with noise treatment : Modelling and sensitivity." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEC028.

Full text

Abstract:

La transmission acoustique de plaques et de coques est un problème présent dans de nombreuses industries, de l'automobile à l'aéronautique en passant par le génie civil. Il s'agit alors, en présence d'une source externe, de limiter le niveau de bruit à l'intérieur d'une cavité enclose par une structure vibrante, qu'il s'agisse d'une voiture, d'un avion ou d'un immeuble.Les matériaux composites sont de plus en plus largement utilisés par toutes les industries du transport, du fait de leur faible masse rapportée à leur grande rigidité. Ces caractéristiques, utiles pour réduire la consommation én

APA, Harvard, Vancouver, ISO, and other styles

39

Cettour-Janet, Raphael. "Modelling the vibrational response and acoustic radiation of the railway tracks." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC040/document.

Full text

Abstract:

Dans un contexte de densification des villes et de leurs réseaux de transport, les gens sont de plus en plus exposés au bruit. Ainsi, le résultat de l'étude d'impact vibro-acoustique joue un rôle primordial dans l'expansion du réseau ferroviaire. L'une des principales sources est le bruit de roulement : La rugosité de la surface de la roue et du rail produit un déplacement imposé sur ces derniers. Ce déplacement entraine une réponse vibratoire des roues et de la voie ferrée et leurs rayonnements acoustiques. Cette thèse propose une amélioration de la modélisation vibro-acoustique de la voie fe

APA, Harvard, Vancouver, ISO, and other styles

40

Torresin, Simone. "Indoor soundscape modelling: Rethinking acoustic comfort in naturally ventilated residential buildings." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/327411.

Full text

Abstract:

The connection with the outdoor acoustic environment created by open windows has so far been one of the main impediments to the adoption of natural ventilation (NV), due to indoor noise levels easily exceeding design requirements. Starting from the apparent conflict between ventilation and acoustic comfort needs, and the potential offered by NV for low-energy cooling and ventilation, the study explores the opportunities for shaping healthy and supportive acoustic environments through sound transmitted via ventilation openings. The research question challenges the traditional approach to acoust

APA, Harvard, Vancouver, ISO, and other styles

41

Allam, Sabry. "Acoustic modelling and testing of advanced exhaust system components for automotive engines." Doctoral thesis, KTH, Aeronautical and Vehicle Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49.

Full text

Abstract:

<p>The increased use of the diesel engine in the passenger car, truck and bus market is due to high efficiency and lower fuel costs. This growing market share has brought with it several environmental issues for instance soot particle emission. Different technologies to remove the soot have been developed and are normally based on some kind of soot trap. In particular for automobiles the use of diesel particulate traps or filters (DPF:s) based on ceramic monolithic honeycombs are becoming a standard. This new exhaust system component will affect the acoustics and also work as a muffler. To pro

APA, Harvard, Vancouver, ISO, and other styles

42

Hjelmervik, Karl Thomas. "Sonar false alarm rate suppression using classification methods based on acoustic modelling." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14912.

Full text

Abstract:

The use of high–resolution, active sonar systems in littoral environments often results in high false alarm rates. False alarm rate inflation (FARI) and non–Rayleigh reverberation (NRR) are two well–documented causes. FARI may occur when the reverberation in the normaliser window is non–stationary, while NRR may occur when the sonar footprint is too small for the central limit theorem to apply for the scatterer statistics. The main originator for false alarms in littoral environments are either the sea floor itself or objects located on the sea floor. Automatic classification methods may be us

APA, Harvard, Vancouver, ISO, and other styles

43

Lippert, Stephan [Verfasser]. "Efficient vibro-acoustic modelling of aircraft components with parameter uncertainties / Stephan Lippert." Aachen : Shaker, 2010. http://d-nb.info/1081884940/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Van, der Kelen Christophe. "Vibro-acoustic modelling of anisotropic poroelastic materials : characterisation of the anisotropic properties." Doctoral thesis, KTH, MWL Strukturakustik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-137809.

Full text

Abstract:

The present-day challenges in the transport industry, steered by the increasing environmental awareness, necessitate manufacturers to take measures to reduce emissions related to the movements of goods and humans. In particular, the measures aiming at a reduced mass or higher load capacity to increase fuel efficiency, generally deteriorate the noise and vibration insulation properties of their products. In order to comply with the regulations and customer demands, modern vehicles increasingly move towards a multifunctional integrated design approach, if possible for all subcomponents involved

APA, Harvard, Vancouver, ISO, and other styles

45

Di, Meglio Alberto. "Finite element-boundary elements modelling of acoustic scattering from viscoelastic anechoic structures." Thesis, University of Birmingham, 2000. http://etheses.bham.ac.uk//id/eprint/488/.

Full text

Abstract:

This research work focuses on the analysis of multi-layered, anechoic tiles for underwater applications, especially in the field of communications. It is firstly shown how the sound absorbing properties of viscoelastic materials can be modified and enhanced by the proper use of fillers, such as lead oxide and mica. Successively, a new method for identifying the viscoelastic frequency-dependent properties of such materials from experimental data is presented. The method is based on a variational method analogous to the Hamilton Principle. It allows calculating hard-to-find properties such as th

APA, Harvard, Vancouver, ISO, and other styles

46

Nyandeni, Zamashobane. "Computational aeroacoustic modelling using hybrid RANS/LES methods with modified acoustic analogies." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25388.

Full text

Abstract:

This study considers a numerical approach to identifying noise mechanisms in tandem cylinders to understand aircraft landing gear as a primary contributor to airframe noise during approach and landing. Fluctuations in the flow properties induced by turbulence are computed as well as the corresponding propagations. A hybrid IDDES turbulence model is employed, to compute the boundary layer and fluctuations in the flow properties. Larsson et al. modified Curle's analogy leading to the derivation of a version of Curle's analogy that makes use of strictly time derivatives which has been proven to b

APA, Harvard, Vancouver, ISO, and other styles

47

Hernández, Vera Ignacio. "Soot modelling in flames and Large-Eddy Simulation of thermo-acoustic instabilities." Thesis, Toulouse, INPT, 2011. http://www.theses.fr/2011INPT0134/document.

Full text

Abstract:

Dans la première partie de cette thèse de doctorat une méthodologie est présentée qui permet de prédire les niveaux de suies produits dans des flammes laminaires monodimensionnelles, ou un modèle semi-empirique de suies est utilisé en combinaison avec une chimie complexe et un solveur radiatif détaillé. La méthodologie est appliquée au calcul de suies dans une série de flammes de diffusion à contre-courant d'éthylène/air. Plusieurs modèles d'oxydation de suies sont testés et les constantes du modèle sont ajustées afin de retrouver un meilleur accord avec les expériences. L'effet des pertes the

APA, Harvard, Vancouver, ISO, and other styles

48

Killeen, Damien Scott. "A Comparison of Acoustic Particle Velocity Modelling Methods for Seismic Airgun Sources." Thesis, Curtin University, 2022. http://hdl.handle.net/20.500.11937/89602.

Full text

Abstract:

Sound waves in the ocean are a fluctuation of both pressure and fluid motion. Fish “hear” this motion, but the guidelines to protect them, and the models used to assess exposure are based on pressure. This thesis proposes methods to model the acoustic motion induced by airgun sound sources used in seismic surveys, validating the models against benchmarks and field-data, finding that they are both more accurate and faster than the methods currently used

APA, Harvard, Vancouver, ISO, and other styles

49

GALUZZI, BRUNO GIOVANNI. "MODELLING AND OPTIMIZATION TECHNIQUES FOR ACOUSTIC FULL WAVEFORM INVERSION IN SEISMIC EXPLORATION." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/545844.

Full text

Abstract:

Full Waveform Inversion has become an important research field in the context of seismic exploration, due to the possibility to estimate a high-resolution model of the subsurface in terms of acoustic and elastic parameters. To this aim, issues such as an efficient implementation of wave equation solution for the forward problem, and optimization algorithms, both local and global, for this high non-linear inverse problem must be tackled. In this thesis, in the framework of 2D acoustic approximation, I implemented an efficient numerical solution of the wave equation based on a local order of app

APA, Harvard, Vancouver, ISO, and other styles

50

GALUZZI, BRUNO GIOVANNI. "Modelling and Optimization Techniques for Acoustic Full Waveform Inversion in Seismic Exploration." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/10281/204387.

Full text

Abstract:

Full Waveform Inversion has become an important research field in the context of seismic exploration, due to the possibility to estimate a high-resolution model of the subsurface in terms of acoustic and elastic parameters. To this aim, issues such as an efficient implementation of wave equation solution for the forward problem, and optimization algorithms, both local and global, for this high non-linear inverse problem must be tackled. In this thesis, in the framework of 2D acoustic approximation, I implemented an efficient numerical solution of the wave equation based on a local order of app

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!