Results 111 to 120 of about 56,039 (156)

Extremely low frequency band station for natural electromagnetic noise measurement

Radio Science, 2015
AbstractA new permanent ELF measurement station has been deployed in Sierra Nevada, Spain. It is composed of two magnetometers, oriented NS and EW, respectively. At 10 Hz, their sensitivity is 19 μV/pT and the signal‐to‐noise ratio (SNR) is 28 dB for a time‐varying signal of 1 pT, the expected field amplitude in Sierra Nevada.
J. Fornieles‐Callejón, A. Salinas, S. Toledo‐Redondo, J. Portí, A. Méndez, E. A. Navarro, J. A. Morente‐Molinera, C. Soto‐Aranaz, J. S. Ortega‐Cayuela   +8 more
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Study on Extremely Low Frequency Atmospheric Noise Signal Processing

2015 International Conference on Information and Communications Technologies (ICT 2015), 2015
Schumann Resonance is seriously disturbed by the industrial environment noise. The SNR of Schumann resonance spectral peaks obtained is very low. The effect of singular value decomposition filtering on Schumann resonance data processing is studied in this paper. The relationship between the number of singular value and SNR is analyzed.
B.X. Cao, N. Yu, Y. Han, H.J. Zhou
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Measurement and shielding of extremely-low-frequency urban magnetic noise

International Journal of Applied Electromagnetics and Mechanics, 2016
Biomagnetic measurements are affected by environmental magnetic noises emitted by various electric systems including trains and elevators. In this study, we measured low-frequency magnetic noise by using a fluxgate magnetometer at a laboratory located in an urban area and analyzed the dominant noise sources during real-world operation of these systems.
Nagase, Masae, Kobayashi, Koichiro, Woo, Taeseong, Takiyama, Yoshihiro, Yamazaki, Keita, Sekino, Masaki   +5 more
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An analog extremely-low-frequency-very-low-frequency atmospheric noise spectrum analyzer on programmable integrated circuits

Instruments and Experimental Techniques, 2015
A functional diagram of the analog extremely-low-frequency-very-low-frequency atmospheric noise spectrum analyzer is presented and its characteristics and spectrum record examples are given. The joint use of programmable analog and digital integrated circuits allows a unit being in the operating state to change in real time such basic parameters of the
A. A. Galakhov, O. I. Akhmetov, V. I. Kirillov   +2 more
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A mathematical model of extremely low frequency ocean induced electromagnetic noise

AIP Conference Proceedings, 2016
Magnetic Anomaly Detection (MAD) system uses the principle that ferromagnetic objects disturb the magnetic lines of force of the earth. These lines of force are able to pass through both water and air in similar manners. A MAD system, usually mounted on an aerial vehicle, is thus often employed to confirm the detection and accomplish localization of ...
Manik Dautta, Rumana Binte Faruque, Rakibul Islam   +2 more
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Independent, modified, and interacting effects of long-term noise, extremely low-frequency electromagnetic fields, and shift work exposures on liver enzymes

Environmental Pollution, 2023
To quantify long-term independent, modified, and interacting effects of noise, extremely low-frequency electromagnetic fields (ELF-EMFs), and shift work exposures on liver enzymes, a four-year repeated measures study was performed among male workers in a thermal power plant industry from 2016 to 2020. The 8-h equivalent sound pressure levels (Leq) were
Masoud Khosravipour, Masoud Ghanbari Kakavandi, Faramarz Gharagozlou, Farshad Nadri, Akbar Barzegar, Khosro Emami, Hossein Valadi Athar   +6 more
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Magnetic noise calculation of mu-metal shields at extremely low frequencies for atomic devices

Journal of Physics D: Applied Physics, 2020
Abstract Mu-metal shields are widely used in atomic devices, but their magnetic noise related to loss is the key performance limit. The magnetic noise can be calculated by using complex permeability and the magnetic field intensity in the shield.
Danyue Ma, Ming Ding, Jixi Lu, Junpeng Zhao, Ke Yang, Xiujie Fang, Kun Wang, Ning Zhang, Bangcheng Han   +8 more
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A CNT based VCO with extremely low phase noise and wide frequency range for PLL application

International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, 2021
AbstractVoltage controlled oscillators (VCOs) are used as key components in phase‐locked loop systems for generating stable oscillation signals. Since the digital electronics industry increasingly needs a faster operation, VCOs need to generate signals at higher frequencies.
Hamed Sarbazi, Reza Sabbaghi‐Nadooshan, Alireza Hassanzadeh   +2 more
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ANALYSIS OF THE POLARIZATION CHARACTERISTICS OF EXTREMELY LOW-FREQUENCY SURFACE MAGNETIC NOISE

PHYSICS OF AURORAL PHENOMENA, 2023
В спектре приземного естественного магнитного шума в диапазоне от долей до нескольких десятков Гц наблюдаются резонансные структуры. Основные из них это шумановский и альвеновский резонансы. Шумановский резонанс, обусловленный кругосветным распространением волн, несет информацию о эффективных глобальных трассах.
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Extremely Low Frequency Noise in Oscillators

1988 Conference on Precision Electromagnetic Measurements, 1988
In the present contribution we have shown the 1/f/sup 2/ noise in oscillators need not be neceesarily generated by environmental temperature fluctuations. As a consequence we investigate a possible theoretical evidence for the relationship between 1/f and l/f/sup 2/ noises.
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