Results 211 to 220 of about 1,026,980 (246)

Turbulent mixing noise from supersonic jets

AIAA Journal, 1993
There is now a substantial body of theoretical and experimental evidence that the dominant part of the turbulent noise of supersonic jets is generated directly by the large turbulence structures/instability waves of the jet flow. Earlier, Tam and Burton provided a description of the physical mechanism by which supersonically traveling instability waves
Tam, Christopher K. W., Chen, Ping
openaire   +2 more sources

Mixed Industry and Traffic Noise Mapping

The Journal of the Acoustical Society of America, 2008
The authors have a large experience on Noise Mapping of both transportation sources and industrial plants. This paper provides examples of Noise Maps for Communities of different sizes with road, railway and industrial sources. The difficulties to estimate Noise Emission from industrial sites are discussed. Recommandations are provided.
Céline Boutin, Alexis Bigot
openaire   +1 more source

Four-wave mixing and thermal noise

AIP Conference Proceedings, 1988
In this paper, we present a statistical thermodynamic analysis of thermal noise in four‐wave mixing. For degenerate four‐wave mixing, we obtain a static susceptibility relation between the Kerr coefficient e2 (related to the signal strength) and light scattering thermal fluctuations (related to the noise). The signal‐to‐noise power ratio (SNR) is given
R. McGraw, D. N. Rogovin
openaire   +1 more source

Low noise two wave mixing deflector

Photorefractive Materials, Effects And Devices Prm'93, 1993
Our deflector scheme is derived from the two wave mixing beam steering system first proposed by D. Rak et al. [1].
P. Mathey, G. Pauliat, G. Roosen
openaire   +1 more source

Mixed‐bandwidth acquisitions: Signal‐to‐noise ratio and signal‐to‐noise efficiency

Journal of Magnetic Resonance Imaging, 2010
AbstractPurposeTo evaluate signal‐to‐noise ratio (SNR) and SNR efficiency in mixed‐bandwidth acquisition (MBA). SNR efficiency describes the achievable SNR per unit time and is a basic aspect in clinical applications to optimize work flow.Materials and MethodsCorresponding simulations were performed and predictions of the theory verified in phantom ...
Morwan, Choli, Peter M, Jakob, Ralf B, Loeffler, Claudia M, Hillenbrand   +3 more
openaire   +2 more sources

Quantum-noise reduction in intracavity four-wave mixing

Physical Review A, 1990
We present a simple quantum model for intracavity four-wave mixing above threshold. A reduction of quantum noise below the shot-noise level is predicted not only for the intensity difference of the signal and idler beams, but for the signal and idler intensity sum and also for the individual signal and idler intensities.
Sanders, B. C., Reid, M. D.
openaire   +3 more sources

Mix Design Factors to Reduce Noise in Hot-Mix Asphalt

Transportation Research Record: Journal of the Transportation Research Board, 2013
Noise generated from high-trafficked roadways is a significant source of noise pollution in urban environments. As population centers continue to expand, so too does the demand for quiet, serviceable pavements. Traffic noise is derived from two basic sources: standard vehicle engine operation and tire–road interaction. Reduction of the former has been
Ling Cong, Daniel Swiertz, Hussain Bahia
openaire   +1 more source

Removal of Mixed Impulse noise and Gaussian noise using genetic programming

2012 IEEE 11th International Conference on Signal Processing, 2012
In this paper, we have put forward a nonlinear filtering method for removing mixed Impulse and Gaussian noise, based on the two step switching scheme. The switching scheme uses two cascaded detectors for detecting the noise and two corresponding estimators which effectively and efficiently filters the noise from the image.
R. P. Aher, K.C. Jodhanle
openaire   +1 more source

In-flight simulation experiments on turbulent jet mixing noise

Journal of Sound and Vibration, 1976
The effects of aircraft forward motion on pure turbulent mixing noise from unheated jets are examined experimentally in the inflight simulation mode. Both acoustic and flow characteristics are determined by testing model-scale nozzles in an anechoic free-jet facility and a wind tunnel, respectively. Scaling laws are derived from each set of experiments
H. TANNA, P. MORRIS
openaire   +1 more source

Binary Encoding of Multiplexed Images in Mixed Noise

IEEE Transactions on Medical Imaging, 2008
Binary coding of multiplexed signals and images has been studied in the context of spectroscopy with models of either purely constant or purely proportional noise, and has been shown to result in improved noise performance under certain conditions. We consider the case of mixed noise in an imaging system consisting of multiple individually-controllable
openaire   +2 more sources