Theoretical and experimental noise investigations of the DRO-type oscillators

1997 ◽  
Vol 18 (6) ◽  
pp. 1199-1216
Author(s):  
Yu. V. Majstrenko ◽  
V. N. Veremey
Keyword(s):  
Experimental Noise

scholarly journals Learning to cope: vocal adjustment to urban noise is correlated with prior experience in black-capped chickadees

2016 ◽  
Vol 283 (1833) ◽  
pp. 20161058 ◽  
Author(s):  
Stefanie E. LaZerte ◽  
Hans Slabbekoorn ◽  
Ken A. Otter
Keyword(s):  
Ambient Noise ◽  
Prior Experience ◽  
Traffic Noise ◽  
Experimental Studies ◽  
Previous Exposure ◽  
Poecile Atricapillus ◽  
Urban Noise ◽  
Experimental Noise ◽  
Avian Communication ◽  
The City

Urban noise can interfere with avian communication through masking, but birds can reduce this interference by altering their vocalizations. Although several experimental studies indicate that birds can rapidly change their vocalizations in response to sudden increases in ambient noise, none have investigated whether this is a learned response that depends on previous exposure. Black-capped chickadees ( Poecile atricapillus ) change the frequency of their songs in response to both fluctuating traffic noise and experimental noise. We investigated whether these responses to fluctuating noise depend on familiarity with noise. We confirmed that males in noisy areas sang higher-frequency songs than those in quiet areas, but found that only males in already-noisy territories shifted songs upwards in immediate response to experimental noise. Unexpectedly, males in more quiet territories shifted songs downwards in response to experimental noise. These results suggest that chickadees may require prior experience with fluctuating noise to adjust vocalizations in such a way as to minimize masking. Thus, learning to cope may be an important part of adjusting to acoustic life in the city.

Toward High-Resolution Mechanical Spectroscopy HRMS - Logarithmic Decrement

2012 ◽  
Vol 184 ◽  
pp. 467-472 ◽  
Author(s):  
Leszek B. Magalas ◽  
M. Majewski
Keyword(s):  
High Resolution ◽  
Low Frequency ◽  
Logarithmic Decrement ◽  
Frequency Resolution ◽  
Mechanical Spectroscopy ◽  
Spectral Leakage ◽  
Experimental Noise ◽  
Relative Errors ◽  
The Way

In this work, we present the comparison between different methods used to compute the logarithmic decrement,δ. The parametric OMI method and interpolated DFT (IpDFT) methods are used to compute theδfrom free decaying oscillations embedded in an experimental noise typical for low-frequency mechanical spectrometers. The results are reported forδ= 5×10-4, = 1.12345 Hz and different sampling frequencies, = 1 kHz and 4 kHz. A new YM algorithm yields the smallest dispersion in experimental points of the logarithmic decrement and the smallest relative errors among all investigated IpDFT methods. In general, however, the IpDFT methods suffer from spectral leakage and frequency resolution. Therefore it is demonstrated that the performance of different methods to compute theδcan be listed in the following order: (1) OMI, (2) YM, (3) YMC, and (4) the Yoshida method, Y. For short free decays the order of the best performers is different: (1) OMI and (2) YMC. It is important to emphasize that IpDFT methods (including the Yoshida method, Y) are discouraged for signals that are too short. In conclusion, the best methods to compute the logarithmic decrement are the OMI and the YM. These methods will pave the way toward high-resolution mechanical spectroscopy HRMS.

The timeline of blood pressure changes and hemodynamic responses during an experimental noise exposure

2018 ◽  
Vol 163 ◽  
pp. 249-262 ◽  
Author(s):  
Katarina Paunović ◽  
Branko Jakovljević ◽  
Vesna Stojanov
Keyword(s):  
Blood Pressure ◽  
Noise Exposure ◽  
Hemodynamic Responses ◽  
Experimental Noise ◽  
Pressure Changes

Experimental noise-free information recovery via reference beam encryption

2018 ◽  
Author(s):  
John Alexis Jaramillo Osorio ◽  
Santiago Montoya ◽  
John Fredy Barrera Ramírez ◽  
Alejandro Velez ◽  
Roberto Torroba ◽  
...  
Keyword(s):  
Reference Beam ◽  
Information Recovery ◽  
Experimental Noise ◽  
Free Information

scholarly journals Separating the Effects of Experimental Noise from Inherent System Variability in Voltammetry: The [Fe(CN)6]3–/4– Process

2018 ◽  
Vol 91 (3) ◽  
pp. 1944-1953 ◽  
Author(s):  
Martin Robinson ◽  
Alexandr N. Simonov ◽  
Jie Zhang ◽  
Alan M. Bond ◽  
David Gavaghan
Keyword(s):  
Experimental Noise ◽  
System Variability

Chapter III. Experimental Noise Studies In Animals

1980 ◽  
Vol 89 (sup366) ◽  
pp. 51-57
Keyword(s):  
Experimental Noise

scholarly journals Experimental Noise Reducers for an Active Microbarograph Array

2010 ◽  
Vol 26 (1-4) ◽  
pp. 41-52 ◽  
Author(s):  
F. H. Grover
Keyword(s):  
Experimental Noise

Development of an Inverse Approach for the Characterization of In Vivo Mechanical Properties of the Lower Limb Muscles

2014 ◽  
Vol 136 (11) ◽  
Author(s):  
Jean-Sébastien Affagard ◽  
Sabine F. Bensamoun ◽  
Pierre Feissel
Keyword(s):  
Sensitivity Analysis ◽  
Displacement Field ◽  
Inverse Method ◽  
Model Updating ◽  
Mechanical Test ◽  
Imaging Techniques ◽  
Image Correlation ◽  
Thigh Muscle ◽  
Experimental Noise ◽  
Numerical Example

The purpose of this study was to develop an inverse method, coupling imaging techniques with numerical methods, to identify the muscle mechanical behavior. A finite element model updating (FEMU) was developed in three main interdependent steps. First, a 2D FE modeling, parameterized by a Neo-Hookean behavior (C10 and D), was developed from a segmented thigh muscle 1.5T MRI (magnetic resonance imaging). Thus, a displacement field was simulated for different static loadings (contention, compression, and indentation). Subsequently, the optimal mechanical test was determined from a sensitivity analysis. Second, ultrasound parameters (gain, dynamic, and frequency) were optimized on the thigh muscles in order to apply the digital image correlation (DIC), allowing the measurement of an experimental displacement field. Third, an inverse method was developed to identify the Neo-Hookean parameters (C10 and D) by performing a minimization of the distance between the simulated and measured displacement fields. To replace the experimental data and to quantify the identification error, a numerical example was developed. The result of the sensitivity analysis showed that the compression test was more adapted to identify the Neo-Hookean parameters. Ultrasound images were recorded with a frequency, gain, and dynamic of 9 MHz, 34 dB, 42 dB, respectively. In addition, the experimental noise on displacement field measurement was estimated to be 0.2 mm. The identification performed on the numerical example revealed a low error for the C10 (<3%) and D (<7%) parameters with the experimental noise. This methodology could have an impact in the scientific and medical fields. A better knowledge of the muscle behavior will help to follow treatment and to ensure accurate medical procedures during the use of robotic devices.

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