improvements in knowledge as well as technology and industrial workers’ exposure to adverse factors have caused more attention to be paid to the workers’ occupational health. according to the report by w.h.o., noise, as one of the most important physical factors of workplace, causes 4 million dollars health damage every day. noise can also reduce the workers’ morale as well as motivation and, c...

background: in the steel industry, coke-fueled furnaces are used for smelting iron ore to produce cast iron are considered as sources of annoying noise.this study aims to evaluate the noise pollution blast furnace and sound source characteristics in order to present noise control measures in the steel industry. methods: measurement of noise level and its frequency analysis was performed using s...

Errors of measurement arise because our observations are affected by many sources of variability, but our conceptual frameworks necessarily ignore much of this variability. Sources of variability that are not included in our models and descriptions of phenomena are treated as error or noise. A good theory of error supports the development of precise measurements, clearly defined constructs and ...

Respiration derivation from ECG signals would be an alternative approach for obtaining respiration related knowledge that is especially useful in the situation in which the respiration is not routinely monitored by specialized equipment. Although several published methods could give reasonable results for this purpose, for some applications, they still have drawbacks in some respects, e.g., req...

In this paper, an intuitive analysis of a phase noise reduction technique is done, and then a modified structure is proposed to achieve higher phase noise reduction than the original one. This method reduces the impact of noise sources on the phase noise by decreasing closed-loop gain in zero-crossings points and moving this high closed-loop gain to the non-zero-crossings points. This reduction...

This research has been carried out to determine the marine propeller hydro-acoustic characteristics by Reynolds-Averaged Navier-Stokes (RANS) solver in both uniform and non-uniform wake flow at different operating conditions Wake flow can cause changes in pressure fluctuation and gas effect on propeller noise spectrum. Noise is generated by the induced trailing vortex wake and induced pressure ...