The purpose of this work was to evaluate the somatosensory system of methylmercury-exposed inhabitants living in the communities of the Tapajós river basin by using psychophysical tests and to compare with measurements performed in inhabitants of the Tocantins river basin. We studied 108 subjects from Barreiras and São Luiz do Tapajós, two communities of the Tapajós river basin, State of Pará, ...

original article   noise and vibration are the common problems in industrialized countries which can affect individual's job performance. the present study aimed to investigate the combination of the whole body vibration and the noise and their effects on the students' mental performance in the laboratory setting. twenty male students of tehran university of medical sciences, tehran, iran were ...

Generally speaking, a vibration system consists of three parts: vibration resource, vibration transfer path, and vibration receiver. Based on the dynamic sensitivity technique, this paper proposes a method for evaluating the contribution of each vibration transfer path to the dynamic response of the vibration receiver. Nonlinear stiffness is an important factor in causing the nonlinearity of vi...

manual citrus harvesting is commonly performing hard, expensive and time consuming. in this study, a factorial experiment with a completely randomized design in three replications was performed to find out the effect of frequency (three levels of 5, 7.5 and 10 hz), vibration time (three levels of 10, 15 and 20 seconds) on harvesting capacity and losses of thomson cultivar of orange. the results...

whole body vibration can deteriorate health bringing about or back pain or spinal column injury, resulted from continuing exposure to vibration. also exposure to vibration can cause disorder in central nervous system and adversely influence vascular and skeletal systems. in this research, the vibration of universal 650m tractor seat and its effect on the operator in five levels of engine speeds...

Basic Terminology of Structural Vibration The term vibration describes repetitive motion that can be measured and observed in a structure. Unwanted vibration can cause fatigue or degrade the performance of the structure. Therefore it is desirable to eliminate or reduce the effects of vibration. In other cases, vibration is unavoidable or even desirable. In this case, the goal may be to understa...

The design of grating-based instruments to handle and condition coherent ultrafast pulses in the extreme-ultraviolet is discussed. The main application of such instruments is the monochromatization of high-order laser harmonics and free-electron-laser pulses in the femtosecond time scale. Broad-band monochromators require the use of diffraction gratings at grazing incidence. A grating can be us...

Probabilistic latent component analysis (PLCA) is applied to the problem of gearbox vibration source separation. A model for the probability distribution of gearbox vibration employs a latent variable intended to correspond to a particular vibration source, with the measured vibration at a particular sensor for each source the product of a marginal distribution of vibration by frequency, a marg...

This paper presents an innovative structural health monitoring (SHM) platform in terms of how it integrates smartphone sensors, the web, and crowdsourcing. The ubiquity of smartphones has provided an opportunity to create low-cost sensor networks for SHM. Crowdsourcing has given rise to citizen initiatives becoming a vast source of inexpensive, valuable but heterogeneous data. Previously, the a...

Neck muscle vibration is known to influence body orientation and posture during locomotion and stance in normal subjects. To verify the hypothesis that neck proprioceptive input can be misinterpreted in patients with cervical dystonia (CD), lateral continuous vibration was applied to the sternocleidomastoid muscle during both stepping-in-place and quiet stance, with eyes closed. The orienting r...