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Power spectral density of subsonic jet noise
Journal of Sound and Vibration, 1985The power-spectrum density (PSD) of the far-field noise of a subsonic unheated axisymmetric jet is investigated by analysis of about 80 sets of published noise spectra and of spectra obtained using 12.7 and 25.4-mm-diameter compressed-air jets at exit velocities 66 and 104 m/s and 67 and 91 m/s, respectively, in the NASA Langley anechoic flow facility.
K.B.M.Q. Zaman, J.C. Yu
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Characterization and reconstruction of VOG noise with power spectral density analysis
Proceedings of the Ninth Biennial ACM Symposium on Eye Tracking Research & Applications, 2016Characterizing noise in eye movement data is important for data analysis, as well as for the comparison of research results across systems. We present a method that characterizes and reconstructs the noise in eye movement data from video-oculography (VOG) systems taking into account the uneven sampling in real recordings due to track loss and inherent ...
Dong Wang +2 more
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Power spectral density of 3D noise
SPIE Proceedings, 2017When evaluated with a spatially uniform irradiance, an imaging sensor exhibits both spatial and temporal variations, which can be described as a three-dimensional (3D) random process considered as noise. In the 1990s, NVESD engineers developed an approximation to the 3D power spectral density (PSD) for noise in imaging systems known as 3D noise.
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Wavelet de‐noising techniques with power spectral density to vibration signal
Kybernetes, 2013PurposeDenoising of the vibration signal is crucial to identify a structure's damage. Based on noise frequency character, the “real” vibration signal can be gotten. The purpose of this paper is to propose a novel method for denoising a signal based on the wavelet transform.Design/methodology/approachThe vibration signal with noise which can be ...
Weizhen Chen +3 more
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Noise power spectral density matrix estimation based on modified IMCRA
2014 48th Asilomar Conference on Signals, Systems and Computers, 2014In this paper, we present a new method for noise power spectral density (PSD) matrix estimation based on IMCRA which consists of two parts. For the auto-PSD (diagonal) estimation, we propose a modification to IMCRA where a special level detector is employed to improve the tracking of non-stationary noise backgrounds.
Qipeng Gong +2 more
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Improved noise power spectral density tracking by a MAP-based postprocessor
2012 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2012In this paper we present a novel noise power spectral density tracking algorithm and its use in single-channel speech enhancement. It has the unique feature that it is able to track the noise statistics even if speech is dominant in a given time-frequency bin.
Aleksej Chinaev +3 more
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Speckle noise in bar-code scanning systems—power spectral density and SNR
Applied Optics, 2003Laser-based flying-spot scanners are strongly affected by speckle that is intrinsic to coherent illumination of diffusing targets. In such systems information is usually extracted by processing the derivative of a photodetector signal that results from collecting over the detector's aperture the scattered light of a laser beam scanning a bar code ...
Marom, E. +2 more
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Azimuthal decomposition of the power spectral density of subsonic jet noise
The Journal of the Acoustical Society of America, 1977The coherence function was measured from two sampled jet noise signals, one from a stationary microphone and the other from a circumferentially moving microphone. The coherence function was then expanded in a Fourier series with respect to the azimuthal angle. For an axisymmetric circular jet the Fourier coefficients thus obtained are equivalent to the
K. Yamamoto, R. E. A. Arndt
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On the noise power spectral density of particulate recording media
IEEE Transactions on Magnetics, 1983The ac-noise power spectrum is investigated. Because of the interaction forces between the particles, the structure of the particulate layer has a dominant influence. This structure is quantified by means of the dc-noise power spectrum. Depending on the dispersion and coating technique the duster structure appears to vary.
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The average power spectral density of cancellation noise in OFDM systems
2013 International Conference on Communications, Circuits and Systems (ICCCAS), 2013Peak cancellation is a widely used technique to reduce peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. However, peak cancellation, when implemented with a window function in time domain, will introduce in-band distortion and out-of-band radiation due to the nonlinear processing.
Qiuyue Ji +4 more
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