Greek, Latin, and English Prosodial Lexicon

Greek, Latin, and English Prosodial Lexicon PDF Author: John Brasse
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Greek, Latin, and English Prosodial Lexicon

Greek, Latin, and English Prosodial Lexicon PDF Author: John Brasse
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description


Atmospheric Acoustic Remote Sensing

Atmospheric Acoustic Remote Sensing PDF Author: Stuart Bradley
Publisher: CRC Press
ISBN: 9781420005288
Category : Technology & Engineering
Languages : en
Pages : 296

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Book Description
Sonic Detection and Ranging (SODAR) systems and Radio Acoustic Sounding Systems (RASS) use sound waves to determine wind speed, wind direction, and turbulent character of the atmosphere. They are increasingly used for environmental and scientific applications such as analyzing ground-level pollution dispersion and monitoring conditions affecting wind energy generation. However, until now there have been no reliable references on SODAR and RASS for practitioners in the field as well as non-experts who wish to understand and implement this technology to their own applications. Authored by an internationally known expert in the design and use of SODAR/RASS technology, Atmospheric Acoustic Remote Sensing: Principles and Applications systematically explains the underlying science, principles, and operational aspects of acoustic radars. Abundant diagrams and figures, including eight pages of full-color images, enhance clear guidelines and tools for handling calibration, error, equipment, hardware, sampling, and data analysis. The final chapter explores applications in environmental research, boundary layer research, wind power and loading, complex terrain, and sound speed profiles. Atmospheric Acoustic Remote Sensing offers SODAR and RASS users as well as general remote sensing practitioners, environmental scientists, and engineers a straightforward guide for using SODARs to perform wind measurements and data analysis for scientific, environmental, or alternative monitoring applications.

The Journal of the Acoustical Society of America

The Journal of the Acoustical Society of America PDF Author: Acoustical Society of America
Publisher:
ISBN:
Category : Acoustical engineering
Languages : en
Pages : 994

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Acoustic Scattering from a Turbulent Vortex

Acoustic Scattering from a Turbulent Vortex PDF Author: Stanford University. Stanford Electronics Laboratories
Publisher:
ISBN:
Category :
Languages : en
Pages : 50

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Book Description
With the aid of the Born approximation, the time autocorrelation and power spectral density are calculated for the received acoustic signal scattered from velocity fluctuations in a turbulent aircraft trailing vortex. The turbulence is required to be globally stationary, but only locally homogeneous. The treatment includes the effects of spectral broadening due to convection of the scattering eddies by a spatially varying mean flow and by macroeddies. The 3 dB bandwidth of the received signal is related to the scattering angle and the core Mach number of the vortex. A primary feature of the analysis is that it provides a method for inferring the radial intensity distribution of turbulence in a vortex. The analysis technique is also applicable to scattering from other turbulent flows where significant variations of turbulence level occur over distances on the order of the macroeddy size. (Author).

Development of the Modern Theory of Sound Propagation in the Turbulent Atmosphere

Development of the Modern Theory of Sound Propagation in the Turbulent Atmosphere PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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The foundations of the modern theory of sound propagation and scattering in a homogeneous and isotropic atmospheric turbulence are developed: The sound scattering cross-section for von Karman spectra of temperature and wind velocity fluctuations is calculated; the rigouros theory of line of sight sound propagation in an atmosphere with Kolmogorov, Gaussian and von Karman spectra of temperature and wind velocity fluctuations is developed; a new theoretical formulation of the interference of the direct wave from source to receiver and that reflected from the ground in a turbulent atmosphere is presented; the sound scattering cross section in an atmosphere with arbitrary profiles of temperature and wind velocity is calculated; some predictions of the modern theory are verified experimentally; correct wideangle parabolic equations for sound waves in a turbulent atmosphere are derived and used for numerical simulations of sound propagation. The modern theory has already been adopted by scientists for calculations of sound propagation in turbulent media and as a basis for development of new acoustic remote sensing techniques of the atmosphere and ocean in several countries and organizations including the U.S. Army Research Laboratory.

Acoustic Interactions with Submerged Elastic Structures: Acoustic scattering and resonances

Acoustic Interactions with Submerged Elastic Structures: Acoustic scattering and resonances PDF Author: Ardéshir Guran
Publisher: World Scientific
ISBN: 9789810229641
Category : Science
Languages : en
Pages : 380

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Book Description
"\berall's work in acoustic and electromagnetic scattering has evoked much interest, in the US as well as abroad, because of its possible practical applications, as well as the theoretical understanding. Many collaborators have been inspired by it, and have now contributed to this volume. The book is an excellent contribution to the literature of Acoustics and Wave Propagation. Professor Guran is to be congratulated for organizing and editing this volume." Prof. Hans A Bethe Noble Laureate Cornell University, 1996

Acoustic Scattering Into Shadow Zones from Atmospheric Turbulence

Acoustic Scattering Into Shadow Zones from Atmospheric Turbulence PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 11

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Book Description
When acoustic scattering estimates are desired from atmospheric regions containing fully developed isotropic homogeneous turbulence, scattering formulas based upon statistical representations of the turbulence well represent the experimental results. However, there is a class of battlefield scenarios where these provisos of fully developed, isotropic and homogeneous sometimes do not apply. The example of this class that is most familiar is that of source and detector near the ground. At ground level, the wind velocity is zero, while at altitude it is not. Thus a gradient of wind velocity exists. There exists often a temperature gradient caused by heating or cooling of the air by contact with the ground. These gradients are recognized in propagation codes by modeling the atmosphere as stratified with each stratum bounded by planes parallel to the assumed flat ground. The anisotropy of the atmosphere near the ground recognized in propagation codes carries over into the generation of turbulence. The above discussion leads to the conclusion that anisotropy in turbulence is to be expected in scenarios played out near the ground, scenarios common to Army operations. The understanding that high sound levels in shadow zones (those regions in an acoustical field in which no sound can reach if the field is determined by ray theory) is caused by scattering from turbulence is very important. This importance arises from the possibility that shadow zone sensors may be used to achieve passive non-line-of-sight detection of enemy assets. This paper unites the above considerations by calculating the shadow zone signal level for a representative battlefield scenario using a structural model of turbulence.

Acoustic Interactions With Submerged Elastic Structures - Part I: Acoustic Scattering And Resonances

Acoustic Interactions With Submerged Elastic Structures - Part I: Acoustic Scattering And Resonances PDF Author: Ardeshir Guran
Publisher: World Scientific
ISBN: 9814499730
Category : Science
Languages : en
Pages : 369

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Book Description
The interaction of acoustic fields with submerged elastic structures, both by propagation and scattering, is being investigated at various institutions and laboratories world-wide with ever-increasing sophistication of experiments and analysis. This book offers a collection of contributions from these research centers that represent the present state-of-the-art in the study of acoustic elastic interaction, being on the cutting edge of these investigations. This includes the description of acoustic scattering from submerged elastic objects and shells by the Resonance Scattering Theory of Flax, Dragonette and Überall, and the interaction of these phenomena in terms of interface waves. It also includes the use of this theory for the purpose of inverse scattering, i.e. the determination of the scattered objects properties from the received acoustic backscattered signals. The problem of acoustically excited waves in inhomogeneous and anisotropic materials, and of inhomogeneous propagating waves is considered. Vibrations and resonances of elastic shells, including shells with various kinds of internal attachments, are analyzed. Acoustic scattering experiments are described in the time domain, and on the basis of the Wigner-Ville distribution. Acoustic propagation in the water column over elastic boundaries is studied experimentally both in laboratory tanks, and in the field, and is analyzed theoretically. Ultrasonic nondestructive testing, including such aspects like probe modelling, scattering by various types of cracks, receiving probes and calibration by a side-drilled hole is also studied in details.A comprehensive picture of these complex phenomena and other aspects is presented in the book by researchers that are experts in each of these domains, giving up-to-date accounts of the field in all these aspects.

The Effects of Large and Small Scale Turbulence on Sound Propagation in the Atmosphere

The Effects of Large and Small Scale Turbulence on Sound Propagation in the Atmosphere PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 64

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Book Description
Propagation of acoustic waves in the atmosphere is affected by several mechanisms. Two of the effects are the scattering of sound by small-scale atmospheric turbulence and fluctuation of the speed of sound gradients by the passage of large-scale atmospheric turbulence. Small- and large-scale atmospheric turbulence causes the acoustic waves to be altered by different mechanisms. Until recently, the majority of work in turbulence effect on acoustics has concentrated on the small-scale turbulence regime of the inertial subrange of the Kolmogorov spectrum. Earlier small-scale turbulence models have concentrated on the statistical-based work of Tatarski. Current turbulence models deal more with the structural nature of the turbulence because the statistical approach does not account for all of the turbulence effects being measured during acoustic propagation experiments. The large-scale turbulence problem cannot be handled very well with a statistical approach to atmospheric turbulence because the regime of the large-scale turbulence extends into the energy containing subrange or sometimes referred to as the source region. This report discusses the current and past turbulence models used to treat the effect of small- and large-scale turbulence on atmospheric acoustic propagation. (AN).

Structure Function Spectra and Acoustic Scattering Due to Homogeneous Isotropic Atmospheric Turbule Ensembles

Structure Function Spectra and Acoustic Scattering Due to Homogeneous Isotropic Atmospheric Turbule Ensembles PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
Expressions are derived for the spectral densities of the temperature and velocity structure functions of atmospheric turbulence, and for the corresponding Born approximation far field acoustic scattering cross sections, due to homogeneous isotropic stationary ensembles of self similar localized turbules having many different scale lengths. It is shown that for some range Kmin