Ground Vibration, Infrasound and Low Frequency Noise Measurements from a Modern Wind Turbine

2013 ◽  
Vol 99 (4) ◽  
pp. 537-544 ◽  
Author(s):  
Paul Botha
Keyword(s):  
Wind Turbine ◽  
Low Frequency ◽  
Ground Vibration ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Noise Measurements

scholarly journals LOW-FREQUENCY NOISE MEASUREMENTS OF IR PHOTODETECTORS WITH VOLTAGE CROSS CORRELATION SYSTEM

Measurement ◽  
2021 ◽  
pp. 109867
Author(s):  
Krzysztof ACHTENBERG ◽  
Janusz MIKOŁAJCZYK ◽  
Carmine CIOFI ◽  
Graziella SCANDURRA ◽  
Krystian MICHALCZEWSKI ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Low Frequency ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Ir Photodetectors ◽  
Noise Measurements ◽  
Correlation System

Low Frequency Noise from a Big Building Due to Oscillatory Forces of a Machine

1982 ◽  
Vol 1 (1) ◽  
pp. 22-27 ◽  
Author(s):  
Niichi Nishiwaki ◽  
Noboru Fujio ◽  
Takuji Mori
Keyword(s):  
Low Frequency ◽  
Ground Vibration ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Ground Acceleration ◽  
Building Frames ◽  
Acceleration Level ◽  
Residential District ◽  
Factory Building ◽  
Grinding Mill

People living in houses near a big factory complained about chattering of glass windows. At one of these houses, the SPL of low frequency noise was about 66 dB at 5.5 Hz and ground acceleration level was about 40 dB at 9 Hz in the horizontal direction. (0 dB acceleration = 10−5 m/s2). We found that the noise and ground vibration were caused by a big grinding mill in the factory, because both SPL and acceleration level at the residential district were considerably decreased when the mill was not in operation. We also confirmed that low frequency noise was not transmitted from the grinding mill directly, but was due to the resonant vibration of walls of the factory building. Two ideas are studied here to suppress the noise, one of which is to isolate the vibration of the grinding mill at its foundation, and the other is to improve the stiffness of the building frames to stop the wall vibration. As a result of the study, the latter method to increase the stiffness of the building was adopted. The SPL of low frequency noise near the wall was decreased.

Low-Frequency Noise Measurements as a Quality Indicator for Ohmic Contacts to n-GaN

2003 ◽  
Vol 433-436 ◽  
pp. 677-680 ◽  
Author(s):  
Nobuhisa Tanuma ◽  
Hirokazu Tanizaki ◽  
Saburo Yokokura ◽  
T. Matsui ◽  
Sumihisa Hashiguchi ◽  
...  
Keyword(s):  
Quality Indicator ◽  
Ohmic Contacts ◽  
Low Frequency ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Noise Measurements
Sign in / Sign up

Export Citation Format

Share Document