Recurrence Plot Analysis of HRV for Exposure to Low-Frequency Noise

Previous studies have indicated that the chronic effects of exposure to low-frequency noise causes annoyance. However, during the past two decades, most studies have employed questionnaires to characterize the effects of noise on psychosomatic responses. This study investigated cardiovascular activity changes in exposure to low-frequency noise for various noise intensities by using recurrence plot analysis of heart rate variability (HRV) estimation. The authors hypothesized that distinct noise intensities affect cardiovascular activity, which would be reflected in the HRV and recurrence quantification analysis (RQA) parameters. The test intensities of noises were no noise, 70-dBC, 80-dBC, and 90-dBC. Each noise level was sustained for 5 min, and the electrocardiogram (ECG) was recorded simultaneously. The cardiovascular responses were evaluated using RQA of the beat-to-beat (RR) intervals obtained from ECG signals. The results showed that the mean RR interval variability and mean blood pressure did not substantially change relative to the noise levels. However, the length of the longest diagonal line (Lmax) of the RQA of the background noise (no noise) condition was significantly lower than the 70-dBC, 80-dBC, and 90-dBC noise levels. The laminarity showed significant changes in the noise levels of various intensities. In conclusion, the RQA-based measures appear to be an effective tool for exposure to low-frequency noise, even in short-term HRV time series.

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Spectral Characteristics of Heart Rate Variability in Noise Exposure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1079-1080.515 ◽

2014 ◽

Vol 1079-1080 ◽

pp. 515-521

Author(s):

Li Ho Tseng ◽

Ching Chang Yang ◽

Yuan Po Lee ◽

Hong Zhun Wu ◽

Chia Yi Chou

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Spectral Analysis ◽

Background Noise ◽

Low Frequency ◽

Cardiovascular Responses ◽

Frequency Noise ◽

Cardiovascular Activity ◽

Low Frequency Noise ◽

Noise Levels

Ecological studies have shown that the chronic effects of exposure to environmental noise cause annoyance. However, in the past, most studies have used questionnaires to evaluate the effects of noise pollution on psychosomatic responses. This study investigated cardiovascular activity changes in exposure to low-frequency noise at various noise intensities. The authors hypothesized that distinct noise intensities affect cardiovascular activity, which would be reflected in the spectral analysis parameters. The evaluation intensities of low frequency noises (from 20 to 200 Hz) were background noise (BN), 70-dBC, 80-dBC, and 90-dBC. The electrocardiographic (ECG) data was recorded for 5 minutes under various noise levels. The cardiovascular responses were evaluated using spectral analysis of the beat-to-beat (RR) intervals obtained from ECG signals. The results showed that the average blood pressure and mean RR interval variability did not substantially change relative to the noise levels. However, the low-frequency (LF) power and the ratio of LF power to high-frequency power (LF/HF) from ECG under the BN condition were significantly lower than the 80-dBC, and 90-dBC noise levels. In addition, the normalized LF of the background noise condition was significantly lower than the low-frequency of the noise levels at various intensities. In conclusion, the frequency-domain-based measures appear to be a powerful tool for exposure to low-frequency noise, even in short-term heart rate variability time series.

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Detrended Fluctuation Analysis of Heart Rate Variability in Noise Exposure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1044-1045.1129 ◽

2014 ◽

Vol 1044-1045 ◽

pp. 1129-1134 ◽

Cited By ~ 1

Author(s):

Shih Tsung Chen ◽

Li Ho Tseng ◽

Yuan Po Lee ◽

Hong Zhun Wu ◽

Chia Yi Chou

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Detrended Fluctuation Analysis ◽

Low Frequency ◽

Fluctuation Analysis ◽

Frequency Noise ◽

Cardiovascular Activity ◽

Low Frequency Noise ◽

Rr Intervals ◽

Detrended Fluctuation

During the past two decades, most studies have employed questionnaires to characterize the effects of noise on behavior and health. Developments in physiological techniques have provided a noninvasive method for recording cardiovascular autonomic activity by using an electrocardiogram (ECG). We investigated cardiovascular activity changes in exposure to exposure to low-frequency noise for various noise intensities by using detrended fluctuation analysis (DFA) of heart rate variability (HRV). We hypothesized that distinct noise intensities would affect cardiovascular activity, which would be reflected in the HRV and DFA parameters. A total of 17 healthy volunteers participated in this study. The test intensities of noises were no noise, 70-dBC, 80-dBC, and 90-dBC. Each noise was sustained for 5 minutes and the ECG was recorded simultaneously. The cardiovascular responses were evaluated using DFA of the beat-to-beat (RR) intervals obtained from ECG signals. The results showed that the mean RR intervals variability and mean blood pressure did not substantially change relative to the noises. However, the short-term scaling exponent (α1) of the DFA of the background noise (no noise) condition was lower than the 70-dBC, 80-dBC and 90-dBC noises (P< 0.05, repeated measures analysis of variance). The α1of 90-dBC noise was significantly higher than the α1of BN condition according to a Mann–Whitney U test (P< 0.01). We concluded that exposure to low-frequency noise significantly affects the temporal correlations of HRV, but it does not influence RR intervals variability.

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Effects of aspect ratio on the temperature coefficient of resistance matching and low frequency noise levels in thick film strain sensors

Microelectronics International ◽

10.1108/13565360110380107 ◽

2001 ◽

Vol 18 (1) ◽

pp. 40-43 ◽

Cited By ~ 7

Author(s):

J.K. Atkinson ◽

R.P. Sion ◽

Z. Zhang

Keyword(s):

Aspect Ratio ◽

Temperature Coefficient ◽

Thick Film ◽

Low Frequency ◽

Strain Sensors ◽

Frequency Noise ◽

Low Frequency Noise ◽

Noise Levels ◽

Temperature Coefficient Of Resistance

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Study of measured indoor low-frequency noise levels resulting from outdoor noise sources, using a simplified physical model as well as empirical and FEM calculations

Journal of Vibroengineering ◽

10.21595/jve.2016.17248 ◽

2016 ◽

Vol 18 (4) ◽

pp. 2693-2713

Author(s):

Darius Saliunas ◽

Vitalijus Volkovas ◽

Tomas Janusevicius

Keyword(s):

Physical Model ◽

Low Frequency ◽

Frequency Noise ◽

Low Frequency Noise ◽

Noise Levels ◽

Noise Sources

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Annoyance Due to Environmental Low Frequency Noise and Source Location — A Case Study

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1177/026309238900800201 ◽

1989 ◽

Vol 8 (2) ◽

pp. 30-39 ◽

Cited By ~ 7

Author(s):

R.N. Vasudevan ◽

H.G. Leventhall

Keyword(s):

Field Study ◽

Microphone Array ◽

Low Frequency ◽

Source Location ◽

Frequency Noise ◽

Low Frequency Noise ◽

Noise Levels ◽

Industrial Source

This case study shows that objective criteria usually based solely on the dB(A) scale are not adequate in evaluating the annoyance due to low frequency noise. Levels which are often low enough to discount the likelihood of a noise nuisance, however, were found to be subjectively annoying. The field study reported here demonstrates that the complainant's annoyance response was due more to the unpleasant nature of the low frequency noise than to its actual level. Positive location of a distant industrial source with the aid of a specially designed three element microphone array provided much needed relief to the complainant.

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Spatiotemporal patterns of avian vocal activity in relation to urban and rural background noise

Journal of Ecoacoustics ◽

10.22261/jea.z9tqhu ◽

2017 ◽

Vol 1 (1) ◽

pp. 1-1 ◽

Cited By ~ 4

Author(s):

Katherine E. Gentry ◽

David A. Luther

Keyword(s):

Background Noise ◽

Activity Patterns ◽

Low Frequency ◽

Rural Landscape ◽

Signal Interference ◽

Frequency Noise ◽

Low Frequency Noise ◽

Noise Levels ◽

Frequency Bands ◽

Vocal Activity

Background noise can interfere with and influence acoustic communication behavior. Signal interference is dependent on the amplitude and spectral characteristic of background noise, which varies over space and time. The likelihood of signal interference is greater when background noise is concentrated within the same frequency bands of an animal’s vocalization, but even a partial masking effect can elicit signaling behavior modification. Relative to a rural landscape, background noise in an urban landscape is disproportionately comprised by anthro- pogenic sound, which fluctuates in amplitude throughout the day and occurs primarily in low frequencies (0–2 kHz). In this study, we examined if urban-rural differences in vocal activity patterns exist in a species Zonotrichia leucophrys nuttalli that communicates above the frequency range of anthropogenic noise (2–8 kHz). We tested whether vocal activity patterns changed in relation to sound in the high or low frequency bands within and between urban and rural locations. Automated acoustic recording devices (ARDs) continuously recorded throughout the morning song chorus, 0500 to 1,100 h, during the 2014 breeding season in San Francisco (urban) and Marin (rural) Counties, CA. Supervised learning cluster analysis was used to quantify vocal activity by totaling the number of songs. In general, vocal activity was greater in urban locations com- pared to rural locations. However, within rural and urban study sites, we found vocal activity decreased where low frequency noise levels were higher. There was not a relationship between vocal activity and high frequency, biotic sound. In both urban and rural locations, low frequency noise levels increased through the morning, while vocal activity remained relatively consistent. Our results demonstrate how patterns of vocal activity can change with low frequency, abiotic noise, even when there is no direct spectral overlap with the acoustic signal.

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GEOMETRY AND BIAS DEPENDENCE OF LOW-FREQUENCY RANDOM TELEGRAPH SIGNAL AND 1/f NOISE LEVELS IN MOSFETS

Fluctuation and Noise Letters ◽

10.1142/s0219477505002999 ◽

2005 ◽

Vol 05 (04) ◽

pp. L539-L548 ◽

Cited By ~ 16

Author(s):

MASATO TOITA ◽

LODE K. J. VANDAMME ◽

SHIGETOSHI SUGAWA ◽

AKINOBU TERAMOTO ◽

TADAHIRO OHMI

Keyword(s):

Low Frequency ◽

Frequency Noise ◽

Gate Bias ◽

Low Frequency Noise ◽

Noise Levels ◽

Temperature Plasma ◽

Random Telegraph Signal ◽

Carrier Traps ◽

Inherent Nature ◽

Bias Condition

Low-frequency noise in MOSFETs is considered to originate from two distinctive sources: Random Telegraph Signal caused by carrier traps at the border of the SiO 2/ Si interface and 1/f fluctuation due to inherent nature of lattice scattering in a Si crystal. It is very important to distinguish these two mechanisms. Relative amplitude of RTS and 1/f noise depends on the number of carriers under the gate electrode, which makes it channel size as well as gate-bias dependent. In this paper, we discuss the dependence of the amplitudes of RTS and 1/f noise in MOSFETs on sample geometry and gate bias condition. We discuss low-frequency noise reduction by utilizing low electron-temperature plasma for gate oxidation as well.

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