Results 31 to 40 of about 2,071,116 (352)

Impact of cyclostationarity on fan broadband noise prediction [PDF]

, 2017
One of the dominant noise sources of modern Ultra High Bypass Ratio (UHBR) engines is the interaction of the rotor wakes with the leading edges of the stator vanes in the fan stage. While the tonal components of this noise generation mechanism are fairly
Attila M Wohlbrandt, Carolin Kissner, S'ebastien Gu'erin   +2 more
semanticscholar   +1 more source

Mechanisms of broadband noise generation on metal foam edges

The Physics of Fluids, 2019
The turbulent flow over a porous trailing edge of a NACA 0018 airfoil is experimentally investigated to study the link between the hydrodynamic flow field and the acoustic scattering.
A. Rubio Carpio, F. Avallone, D. Ragni, M. Snellen, S. van der Zwaag   +4 more
semanticscholar   +1 more source

The Impact of Noise Models on Capacity Performance of Distribution Broadband over Power Lines Networks

Journal of Computer Networks and Communications, 2016
This paper considers broadband potential of distribution Broadband over Power Lines (BPL) networks when different well-known noise models of the BPL literature are applied. The contribution of this paper is twofold.
Athanasios G. Lazaropoulos
doaj   +1 more source

Instrument self-noise and sensor misalignment [PDF]

Advances in Geosciences, 2013
In this study we investigate self-noise of RefTekTM 151-60A "Observer" broadband seismometers (flat to velocity between 50 Hz down to T0=60 s, f0≈17 mHz) using the coherency analysis method introduced by Sleeman et al. (2006).
A. Gerner, G. Bokelmann
doaj   +1 more source

Numerical analysis of broadband noise reduction with wavy leading edge

Chinese Journal of Aeronautics, 2018
Large Eddy Simulation (LES) is performed to investigate the airfoil broadband noise reduction with wavy leading edge under anisotropic incoming turbulence. The anisotropic incoming turbulence is generated by a rod with a diameter of 10 mm.
Fan Tong, W. Qiao, Weijie Chen, Haoyi Cheng, Renke Wei, Xunnian Wang   +5 more
semanticscholar   +1 more source

Spectrum-driven acoustic metasurface for broadband noise control

Results in Physics
To address the issue of broadband noise with tonal characteristics in indoor environments, a spectrum-driven acoustic metasurface (SAM) is proposed in this study.
Qinhao Lin, Junhui Shi, Jin Zhang, Junyi Qiu, Guoqing Di   +4 more
doaj   +1 more source

Combination of Robust Algorithm and Head-Tracking for a Feedforward Active Headrest

Applied Sciences, 2019
Active headrest can reduce the low-frequency noise around ears based on the principle of active noise control. This paper presents a combination of robust algorithm and head-tracking for a feedforward active headrest to reduce the broadband noise for a ...
Rong Han, Ming Wu, Chen Gong, Shangshuai Jia, Tieli Han, Hongling Sun, Jun Yang   +6 more
doaj   +1 more source

Numerical and Experimental Investigations of Modal Coherence Characteristics for the Determination of Broadband Noise in Flow Ducts

Frontiers in Energy Research, 2022
This paper presents a detailed investigation about the modal coherence characteristics of turbomachinery noise. The modal coherence characteristics of ducted noise at high frequencies are investigated by establishing three kinds of ducted sound source ...
Kunbo Xu, Cunliang Liu, Fan Tong, Weiyang Qiao   +3 more
doaj   +1 more source

A Low Noise Receiver for Submillimeter Astronomy [PDF]

, 1986
A broadband, low noise heterodyne receiver, suitable for astronomical use, has been built using a Pb alloy superconducting tunnel junction (SIS). The RF coupling is quasioptical via a bowtie antenna on a quartz lens and is accomplished without any tuning
Miller, R. E., Phillips, T. G., Wengler, M. J., Woody, D. P.   +3 more
core   +1 more source

Effects of Different Spectral Shapes and Amplitude Modulation of Broadband Noise on Annoyance Reactions in a Controlled Listening Experiment

International Journal of Environmental Research and Public Health, 2018
Environmental noise from transportation or industrial infrastructure typically has a broad frequency range. Different sources may have disparate acoustical characteristics, which may in turn affect noise annoyance.
B. Schäffer, R. Pieren, Sabine J Schlittmeier, M. Brink   +3 more
semanticscholar   +1 more source