OBJECTIVES To determine the extent of hand transmitted vibration exposure problems, particularly hand-arm vibration syndrome (HAVS), among construction workers in Malaysia. METHODS A cross-sectional study was conducted on a construction site in Kuala Lumpur, Malaysia. 243 workers were recruited. Questionnaire interviews and hand examinations were administered to 194 respondents. Vibration mag...

with the prolonged use of domestic centrifugal pump, due to erosion, corrosion and an unbalance the sever vibration of the pump are resulted. an erratic sound coming out of pump makes the user uncomfortable. here, tuned vibration absorber (tva) is used as a vibration controlling device. it is designed to reduce the rms velocity below 20% of the circumferential speed, at which the impeller is ba...

Although many rail travellers use portable computers while travelling, the train environment has not been influenced by the desire to operate computers. Some trains provide power points and tables for portable computers, but an optimal design also requires understanding of how typing is disturbed by train motion. There are numerous studies of typing in static conditions and many studies of the ...

Touch of the hand with a stationary surface at nonmechanically supportive force levels (<1 N) greatly attenuates postural sway during quiet stance. We predicted such haptic contact would also suppress the postural destabilization caused by vibrating the right peroneus brevis and longus muscles of subjects standing heel-to-toe with eyes closed. In experiment 1, ten subjects were tested under fou...

We studied the effect of vibratory stimulation of different leg muscles [bilateral quadriceps (Q), hamstring (HS) muscles, triceps surae (TS), and tibialis anterior (TA)] in seven normal subjects during 1) quiet standing, 2) stepping in place movements, and 3) walking on the treadmill. The experiments were performed in a dimly illuminated room, and the subjects were given the instruction not to...

OBJECTIVES To investigate the changes over a workshift in fingertip tactile perception thresholds in users of impact wrenches exposed to intermittent hand transmitted vibration. A further aim was to assess the relation between acute changes in tactile sensation, sensorineural disorders, and vibration dose. METHODS The study populations consisted of 30 workers exposed to vibration (16 men and ...

The effect of periodic vibration noise in wellsite is an important factor which impact analysis on three-dimensional drill string vibration signal. In order to obtain more accurate characters of three-dimensional drill string vibration signal that reflects the drilling tools condition, we conduct researches on the periodic vibration noise in the wellsite, independent component analysis algorith...

Transformer tank vibration has been used for the condition monitoring and fault diagnosis of power transformers, as well as for the evaluation of radiated sound power from such power transformers. In both applications, seeking a correlation between transformer tank vibration and the vibration of the transformer windings and core becomes a challenge for fault identification and noise control at ...

Passive vibration shunt control using piezoelectric materials and an electrical network can remove vibration energy from structures. However, the vibration shunt control efficiency relies on the optimization of the vibration energy transfer between a structure and a Lead-Zirconate-Titanate piezoelectric ceramic material. We present an analytical study of a parallel resistor-inductor piezoelectr...

Random vibration applied to skin can change the sense of touch. Specifically, low amplitude white-noise vibration can improve fingertip touch perception. In fact, fingertip touch sensation can improve even when imperceptible random vibration is applied to other remote upper extremity areas such as wrist, dorsum of the hand, or forearm. As such, vibration can be used to manipulate sensory feedba...