This paper investigates the effect of various modifications to an acoustic steel string guitar on lowfrequency dynamics and sound pressure level. Modifications include string tension, sound-hole area and depth, bridge pin mass, top plate mass, stiffness and damping. Frequency response measurements are provided for all modifications considered. A lumped parameter model is found to capture the ch...

  Abstract   Background: Previous studies have indicated an unspecific correlation between noise   exposure and blood pressure disturbances. Blood pressure disturbances could be caused   by the environmental hazards such as noise exposure. The aim of this study is to analyze   whether there is a relationship between noise exposure and hypertension.   Methods: Atotal sample of 218 workers workin...

original article   introduction: wind-turbine noise emission and its environmental impact are considerable issues nowadays. considering the importance of the issue, the purpose of this study was to prepare noise map and wind turbines sound characteristics on the largest wind farm of iran. method: this study was carried out in two phases:1) in order to prepare the daytime sound level (ld) noise ...

BACKGROUND AND PURPOSE Switching of magnetic field gradients is the primary source of acoustic noise in MR imaging. Sound pressure levels can run as high as 120 dB, capable of producing physical discomfort and at least temporary hearing loss, mandating hearing protection. New technology has made quieter techniques feasible, which range from as low as 80 dB to nearly silent. The purpose of this ...

background : cement industry has many process units. basically all of these units can be considered as a source of noise. since noise pollution is defined based on its offensive hearing effects, the importance of the noise sources depends directly on the number of workers in the unit.   materials and methods : an experimental study has been done at tehran cement factory to recognize and analyze...

Background: Ototoxic chemicals can impair the sense of hearing and balance. In the past decades, the ototoxicity of solvents and their interaction with noise have become evident. This study has been carried out in the shoe manufacturing factory in Tehran (Iran) with the aim of evaluating the combined effects of noise and toluene on the workers' hearing. Materials and Methods: This cross-sect...