background : the application of ventilation systems in industries and workplaces is with the aim of improving environmental conditions for employees. the lack of appropriate ventilation system components design and control methods result in the production of sound and vibration in most components. the purpose of this study was to determine the role of the pad isolator in controlling vibration a...

structural dynamic parameters: natural period, shape modes and damping ratio of vibration, play a decisive role on the seismic behavior of those structures. there are several methods for determining of the structural dynamic parameters, such as: free vibration, ambient vibration and force vibration tests. in this research the structural response of a three-story building (the natural frequencie...

the purpose of this study was to assess exposure to hand-arm vibration in tiller users, forty users of tiller in northeastern provinces of iran were examined to measure hand-arm vibration parameters such as root mean square acceleration (rms), total equivalent acceleration, vibration dose value (vdv) and crest factor in three directions (x, y, and z) and various operating modes for comparing th...

in this paper, the effects of transverse cracks on rotating shaft were studied. according to earlier works, crack shaft failure decrease the critical speed of the shaft and also exhibit a nonlinear vibration behaviour leading to increases the amplitude of 1x and 2x harmonics (first and second order of rotational speed in torsional vibration). this suggests that the application of order analysis...

Progress in developing a web-based Statics course through foundation support is reported. This course is part of a larger initiative that seeks to create and sustain freely available, cognitively informed learning tools designed to provide a substantial amount of instruction through the digital learning environment. Courses are interactive and self-correcting, by providing substantial feedback ...