High cycle fatigue (HCF) cracks generated by compressor blade vibrations are a common source of failure in gas turbine engines. Current methods for crack detection are costly, time consuming, and prone to errors. In-situ blade vibration detection would help operators avoid critical engine speeds, and help infer the presence of cracks via a change in the mode of a blade. Blade vibrations can be ...

1 GPS-based travel survey is an emerging data collection method in transportation planning. 2 Its application in trip mode detection has been explored in many existing studies. 3 However, most existing research on GPS data based trip mode detection methods are 4 developed and tested with data collected from European and American countries. Their 5 methods cannot be easily adapted to Asian count...

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...

The calibration of vibration and acceleration pick-ups (hereinafter pick-ups) has become increasingly important due to the growing needs for accurate measurements of vibration and acceleration. To date, there is no official standard for calibration of the pick-ups in the middle to high vibration frequency rage (80 Hz ~ 5 kHz) in Japan. Thus the reliability of the vibration and acceleration meas...

in the past, rock slope stability analysis were performed either graphically or using a hand-held calculator, but nowadays there are variety of slope stability analysis which can be used according to the field condition and potential failure mode. in 2-d analysis, effect of convex and concave walls are neglected, however concave slopes are believed to be more stable than straight walls due to t...

In this paper a multiobjective optimal design method of interior permanent magnet synchronous motor ( IPMSM) for traction applications so as to maximize average torque and to minimize torque ripple has been presented. Based on train motion equations and physical properties of train, desired specifications such as steady state speed, rated output power, acceleration time and rated speed of tract...