Background and Objectives: Sound of motorcycles plays an important role in noise pollution in big cities. This is due to the lack of national law or standards to control the noise of domestic and also imported motorcycles. This study tries to introduce a practical limit value in different stage of motorcycle life cycle by assessing their noise pollution. Materials and Methods: First the motorcy...

Introduction: Electrocardiogram (ECG) is a method to measure the electrical activity of the heart which is performed by placing electrodes on the surface of the body. Physicians use observation tools to detect and diagnose heart diseases, the same is performed on ECG signals by cardiologists. In particular, heart diseases are recognized by examining the graphic representation of heart signals w...

Valvetrain is one of the major sources of noise and vibration in IC engines. The importance of cam surface quality parameters is highlighted in the valve train mechanisms with direct sliding contact between cam and tappet. In this paper, the influence of surface quality parameters on high frequency noise producing is investigated. The roughness and waviness of some intake and exhaust camshafts ...

Sound travels very efficiently underwater, so the potential area impacted can be thousands of square kilometers or more. Anthropogenic activities such as commercial shipping, recreational activities, drilling, seismic exploration or energy production (hydroelectric power plants), have made underwater noise pollution an increasing and perhaps dominant factor in the aquatic environment. Nowadays,...

Background and Aim: Noise pollution is recognized as a major problem in urban areas. Therefore, the current study was aimed to determine noise pollution indices in Birjand old districts. Materials and Methods: In this cross-sectional and analytical-descriptive study, noise measurement was performed by means of "CEL" sound level meter (model 450.490). Equivalent noise level "Leq 10 min" was meas...