UNLABELLED This study determined how backrest inclination and the frequency and magnitude of vertical seat vibration influence vibration discomfort. Subjects experienced vertical seat vibration at frequencies in the range 2.5-25 Hz at vibration magnitudes in the range 0.016-2.0 ms(-2) r.m.s. Equivalent comfort contours were determined with five backrest conditions: no backrest, and with a stati...

In this study, the effect of posture, vibration magnitude and frequency on seat-to-head (STH) and back support-tohead (BTH) transfer functions has been studied under vertical sinusoidal vibration. Twelve healthy male subjects were participated in experimental work to measure vertical vibration transmitted to the occupants head in three representative postures (erect, vertical back on and forwar...

composite steel concrete composite floor used mainly in the commercial and office building has lighter weight and is considered very economical. the light weight natures of this type of floor causes some vibration problems when it is subjected to loadings such as human footstep loading. the dynamic characteristics of these floors are dependent on several parameters such as joist span, girder sp...

ABSTRCT: Elastic bearings have been used on simply supported bridges on high-speed railway in Taiwan to isolate train-induced vibration. However, their influence on dynamic behavior of the vehicle and bridge has not been fully investigated, and their vibration attenuation has not been quantificationally discussed. In this study, spring-damper elements with 12 degrees of freedom are established ...

The vibration transmission to the lumbar and thoracic segments of seated human subjects exposed to whole body vibration of a vehicular nature have been mostly characterised without the back and hand supports, which is not representative of general driving conditions. This non-invasive experimental study investigated the transmission of vertical seat vibration to selected vertebrae and the head ...

Vertical convection (VC) under the action of vertical vibration in a square cavity has been investigated using direct numerical simulation. The simulations are conducted with Prandtl number Pr fixed at 4.38 and Rayleigh Ra ranging from [Formula: see text] to text]. To examine influence vibration, dimensionless frequency is varied range small amplitude First, for low frequency, trivial results o...

In many occupational and leisure environments, the human body is exposed to oscillatory motions of handles, seats and floors which give rise to complex patterns of sensations. Knowledge of differences in sensitivity to the perception of vibration at the hand, seat and foot would assist the identification of sources of discomfort caused by vibration. The objective of this study was to examine th...

in this paper, multi-objective uniform-diversity genetic algorithm (muga) with a diversity preserving mechanism called the ε-elimination algorithm is used for pareto optimization of 5-degree of freedom vehicle vibration model considering the five conflicting functions simultaneously. the important conflicting objective functions that have been considered in this work are, namely, vertical accel...

A compressor was developed using R32 which was a low GWP R32 refrigerant for coping with global warming. However, there is a tendency for vibrations of a compressor to also increase because the circulation of refrigerant increases according to specification for using R32 refrigerant. Since large vibrations of a compressor causes outdoor units to generate solid propagation sound, there is a need...

transmission of blast waves is a complex phenomenon and the characteristics vary with blast design parameters and geo-technical properties of medium. frequency of vibration and triggering component for structural excitation generally quantifies safe vibration magnitude. at closer distance or higher elevations than the blast locations, vertical or transverse component will be the first arrival t...