نتایج جستجو برای: frequency noise

تعداد نتایج: 648515  

Journal: :physical chemistry research 2014
mohamad ghasem mahjani reza moshrefi majid jafarian jaber neshati

entropy as a measure of uncertainty was used to represent the results of the wavelet technique in electrochemical noise analysis. the experimental signals were obtained by recording the electrochemical potential and current noise of 7075 aluminum alloy in 3.5% nacl solution. the electrochemical potential and current noise were decomposed into 16 levels using daubechies wavelets. wavelet output ...

In this paper, the acoustic analysis of noise has been done in automotive cabin at high speed. High-frequency noise sources are applied separately to the roof and floor panels as well as to the windshield of the vehicle, which has been investigated at both the driver's and rear passenger's head. The most important panels that have the most noise emission are specified. In order to analyze high ...

2008
E. Rubiola

As a consequence of a general trend in the physics of oscillators and clocks towards optics, phase and frequency metrology is rapidly moving to optics too. Yet, optics is not replacing the traditional radio-frequency (RF) and microwave domains. Instead, it adds tough challenges. Precision frequency-stability measurements are chiefly based on the measurement of phase noise, which is the main foc...

Journal: :Noise & health 2004
H G Leventhall

Low frequency noise, the frequency range from about 10 Hz to 200 Hz, has been recognised as a special environmental noise problem, particularly to sensitive people in their homes. Conventional methods of assessing annoyance, typically based on A-weighted equivalent level, are inadequate for low frequency noise and lead to incorrect decisions by regulatory authorities. There have been a large nu...

Journal: :international journal of occupational hygiene 0
farshad nadri department of occupational health, school of public health, kerman university of medical sciences, kerman, iran. mohammadreza monazzam department of occupational health, school of public health, tehran university of edical sciences, tehran, iran. narges khanjani department of epidemiology and statistics, school of public health, kerman university of medical sciences, kerman, iran. mohammadreza ghotbi department of occupational health, school of public health, kerman university of medical sciences, kerman, iran. ahmad rajabizade department of environmental health engineering, school of public health, kerman university of medical sciences, kerman, iran. hamed nadri department of occupational health, school of public health, qazvin university of medical sciences, qazvin, iran.

noise is one of the major hazardous occupational exposures and one of the occupations at risk is the transportation industry. however, few studies have measured and reported the amount of noise exposure in drivers. in this study, we evaluated noise exposure among the public transportation bus drivers of one major iranian city, kerman, southeast iran. eighty public transportation buses in the st...

Journal: :international journal of electrical and electronics engineering 0
payman moallemi majid behnampourii

periodic noises are unwished and spurious signals that create repetitive pattern on images and decreased the visual quality. firstly, this paper investigates various methods for reducing the effects of the periodic noise in digital images. then an adaptive optimum notch filter is proposed. in the proposed method, the regions of noise frequencies are determined by analyzing the spectral of noisy...

Journal: :The Journal of the Acoustical Society of America 1987

Journal: :Journal of Physics: Conference Series 2007

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید

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