Results 271 to 280 of about 33,703 (304)

Acoustic measures of lake community size spectra

Canadian Journal of Fisheries and Aquatic Sciences, 2016
Acoustic methods were tested as an alternative to catch data to measure size spectra of freshwater fish communities in Lac du Bonnet (LdB), Manitoba, Canada. Eleven daytime hydroacoustic surveys conducted in 2011 and 2012 enabled length-frequency spectra of fish communities to be calculated within LdB.
Laura J. Wheeland, George A. Rose
openaire   +1 more source

Subharmonics Spectra of Acoustics Excitation in Granular Medium

AIP Conference Proceedings, 2008
The results of experimental research of specific features of acoustical subharmonics excitation in granular medium are considered. It is founded that signal subharmonics registered at the scale of single granular extremely high varies in time and spectrum of this frequency component lies in some band.
Igor B. Esipov, Andrey N. Vilman, Andrey V. Fokin, Bengt Enflo, Claes M. Hedberg, Leif Kari   +5 more
openaire   +1 more source

Transient Response Spectra of Coupled Acoustical Resonators

The Journal of the Acoustical Society of America, 1966
The maximum absolute pressure magnification of a Helmholtz resonator for an excitation of one cycle of a sine wave is 3.14, occurring when the natural period of the system is equal to the excitation period. When two resonators are coupled together, the response is a function of two uncoupled natural frequencies and a coupling frequency of the system ...
N. N. Reddy, Richard L. Lowery
openaire   +1 more source

Acoustic fluctuations and internal waves—Are their spectra related?

The Journal of the Acoustical Society of America, 1976
There is little question that internal waves are one source of acoustic fluctuations. However the relationship is complex. A continuous-tone sound field can propagate along many different paths in the deep ocean. Signals traveling along these paths interfere causing fluctuations in time and space.
R. P. Porter, R. C. Spindel
openaire   +1 more source

Production of directionally limited acoustic power spectra

The Journal of the Acoustical Society of America, 1991
Apparatus 10 (FIG. 1(a)) for providing acoustic power spectra, all defined over a frequency band from signals received in a predetermined time interval, for individually identifiable directions comprises a pair of arrays 11, 11' of omnidirectional microphone elements 12.
Michael J. Greenwood, David P. J. Coughtrie   +1 more
openaire   +1 more source

Acoustic Transmission Spectra in the Penrose Lattice

Physical Review Letters, 1995
, Komuro, , Shirahama, , Kono
openaire   +2 more sources

Acoustic Spectra of Glasses in the System Na2O-B2O3

1978
The subject of the structure of vitreous B2O3 and Na2O-B2O3 glasses has been a controversial one for many years. Initially Warren(l) proposed a theory, based mainly on x-ray studies, that vitreous B2O3 is composed of BO3 triangles, with each oxygen shared between two borons. The addition of Na2O up to 15 mole % introduces extra oxygen into the network,
J. T. Krause, C. R. Kurkjian
openaire   +1 more source

Nonarbitrary regularization of acoustic spectra

Transport Theory and Statistical Physics, 1993
Alexander N. Gorban, Iliya v. Karlin
openaire   +1 more source

Directivity and the Acoustic Spectra of Brass Wind Instruments

The Journal of the Acoustical Society of America, 1942
A single-point harmonic analysis of the pressure wave radiating from a brass instrument is inadequate as a physical expression of the instrument's acoustic output. This is partly due to the dependence of the analysis upon the relative position of the receiver.
openaire   +1 more source

Removal of “acoustic ringing” from NMR spectra

Journal of Magnetic Resonance (1969), 1985
Morris, Gareth A., Toohey, Michael J.
openaire   +3 more sources